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1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
f71d20e9 | 2 | /* |
24b9f0d2 SS |
3 | * Copyright (C) 2002 Richard Henderson |
4 | * Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM. | |
5 | */ | |
51161bfc LR |
6 | |
7 | #define INCLUDE_VERMAGIC | |
8 | ||
9984de1a | 9 | #include <linux/export.h> |
8a293be0 | 10 | #include <linux/extable.h> |
1da177e4 | 11 | #include <linux/moduleloader.h> |
c8424e77 | 12 | #include <linux/module_signature.h> |
af658dca | 13 | #include <linux/trace_events.h> |
1da177e4 | 14 | #include <linux/init.h> |
ae84e324 | 15 | #include <linux/kallsyms.h> |
34e1169d | 16 | #include <linux/file.h> |
3b5d5c6b | 17 | #include <linux/fs.h> |
6d760133 | 18 | #include <linux/sysfs.h> |
9f158333 | 19 | #include <linux/kernel.h> |
b89999d0 | 20 | #include <linux/kernel_read_file.h> |
1da177e4 LT |
21 | #include <linux/slab.h> |
22 | #include <linux/vmalloc.h> | |
23 | #include <linux/elf.h> | |
3b5d5c6b | 24 | #include <linux/proc_fs.h> |
2e72d51b | 25 | #include <linux/security.h> |
1da177e4 LT |
26 | #include <linux/seq_file.h> |
27 | #include <linux/syscalls.h> | |
28 | #include <linux/fcntl.h> | |
29 | #include <linux/rcupdate.h> | |
c59ede7b | 30 | #include <linux/capability.h> |
1da177e4 LT |
31 | #include <linux/cpu.h> |
32 | #include <linux/moduleparam.h> | |
33 | #include <linux/errno.h> | |
34 | #include <linux/err.h> | |
35 | #include <linux/vermagic.h> | |
36 | #include <linux/notifier.h> | |
f6a57033 | 37 | #include <linux/sched.h> |
1da177e4 | 38 | #include <linux/device.h> |
c988d2b2 | 39 | #include <linux/string.h> |
97d1f15b | 40 | #include <linux/mutex.h> |
d72b3751 | 41 | #include <linux/rculist.h> |
7c0f6ba6 | 42 | #include <linux/uaccess.h> |
1da177e4 | 43 | #include <asm/cacheflush.h> |
563ec5cb | 44 | #include <linux/set_memory.h> |
eb8cdec4 | 45 | #include <asm/mmu_context.h> |
b817f6fe | 46 | #include <linux/license.h> |
6d762394 | 47 | #include <asm/sections.h> |
97e1c18e | 48 | #include <linux/tracepoint.h> |
90d595fe | 49 | #include <linux/ftrace.h> |
7e545d6e | 50 | #include <linux/livepatch.h> |
22a9d645 | 51 | #include <linux/async.h> |
fbf59bc9 | 52 | #include <linux/percpu.h> |
4f2294b6 | 53 | #include <linux/kmemleak.h> |
bf5438fc | 54 | #include <linux/jump_label.h> |
84e1c6bb | 55 | #include <linux/pfn.h> |
403ed278 | 56 | #include <linux/bsearch.h> |
9d5059c9 | 57 | #include <linux/dynamic_debug.h> |
ca86cad7 | 58 | #include <linux/audit.h> |
2f3238ae | 59 | #include <uapi/linux/module.h> |
106a4ee2 | 60 | #include "module-internal.h" |
1da177e4 | 61 | |
7ead8b83 LZ |
62 | #define CREATE_TRACE_POINTS |
63 | #include <trace/events/module.h> | |
64 | ||
1da177e4 LT |
65 | #ifndef ARCH_SHF_SMALL |
66 | #define ARCH_SHF_SMALL 0 | |
67 | #endif | |
68 | ||
84e1c6bb MC |
69 | /* |
70 | * Modules' sections will be aligned on page boundaries | |
3b5be16c HZ |
71 | * to ensure complete separation of code and data, but |
72 | * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y | |
84e1c6bb | 73 | */ |
3b5be16c | 74 | #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX |
84e1c6bb | 75 | # define debug_align(X) ALIGN(X, PAGE_SIZE) |
3b5be16c HZ |
76 | #else |
77 | # define debug_align(X) (X) | |
78 | #endif | |
84e1c6bb | 79 | |
1da177e4 LT |
80 | /* If this is set, the section belongs in the init part of the module */ |
81 | #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) | |
82 | ||
75676500 RR |
83 | /* |
84 | * Mutex protects: | |
85 | * 1) List of modules (also safely readable with preempt_disable), | |
86 | * 2) module_use links, | |
87 | * 3) module_addr_min/module_addr_max. | |
24b9f0d2 SS |
88 | * (delete and add uses RCU list operations). |
89 | */ | |
c6b37801 TA |
90 | DEFINE_MUTEX(module_mutex); |
91 | EXPORT_SYMBOL_GPL(module_mutex); | |
1da177e4 | 92 | static LIST_HEAD(modules); |
67fc4e0c | 93 | |
1a7b7d92 | 94 | /* Work queue for freeing init sections in success case */ |
fdf09ab8 DJ |
95 | static void do_free_init(struct work_struct *w); |
96 | static DECLARE_WORK(init_free_wq, do_free_init); | |
97 | static LLIST_HEAD(init_free_list); | |
1a7b7d92 | 98 | |
6c9692e2 | 99 | #ifdef CONFIG_MODULES_TREE_LOOKUP |
106a4ee2 | 100 | |
93c2e105 PZ |
101 | /* |
102 | * Use a latched RB-tree for __module_address(); this allows us to use | |
103 | * RCU-sched lookups of the address from any context. | |
104 | * | |
6c9692e2 PZ |
105 | * This is conditional on PERF_EVENTS || TRACING because those can really hit |
106 | * __module_address() hard by doing a lot of stack unwinding; potentially from | |
107 | * NMI context. | |
93c2e105 PZ |
108 | */ |
109 | ||
110 | static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n) | |
106a4ee2 | 111 | { |
7523e4dc | 112 | struct module_layout *layout = container_of(n, struct module_layout, mtn.node); |
106a4ee2 | 113 | |
7523e4dc | 114 | return (unsigned long)layout->base; |
93c2e105 PZ |
115 | } |
116 | ||
117 | static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n) | |
118 | { | |
7523e4dc | 119 | struct module_layout *layout = container_of(n, struct module_layout, mtn.node); |
93c2e105 | 120 | |
7523e4dc | 121 | return (unsigned long)layout->size; |
93c2e105 PZ |
122 | } |
123 | ||
124 | static __always_inline bool | |
125 | mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b) | |
126 | { | |
127 | return __mod_tree_val(a) < __mod_tree_val(b); | |
128 | } | |
129 | ||
130 | static __always_inline int | |
131 | mod_tree_comp(void *key, struct latch_tree_node *n) | |
132 | { | |
133 | unsigned long val = (unsigned long)key; | |
134 | unsigned long start, end; | |
135 | ||
136 | start = __mod_tree_val(n); | |
137 | if (val < start) | |
138 | return -1; | |
139 | ||
140 | end = start + __mod_tree_size(n); | |
141 | if (val >= end) | |
142 | return 1; | |
106a4ee2 | 143 | |
106a4ee2 RR |
144 | return 0; |
145 | } | |
146 | ||
93c2e105 PZ |
147 | static const struct latch_tree_ops mod_tree_ops = { |
148 | .less = mod_tree_less, | |
149 | .comp = mod_tree_comp, | |
150 | }; | |
151 | ||
4f666546 PZ |
152 | static struct mod_tree_root { |
153 | struct latch_tree_root root; | |
154 | unsigned long addr_min; | |
155 | unsigned long addr_max; | |
156 | } mod_tree __cacheline_aligned = { | |
157 | .addr_min = -1UL, | |
106a4ee2 | 158 | }; |
106a4ee2 | 159 | |
4f666546 PZ |
160 | #define module_addr_min mod_tree.addr_min |
161 | #define module_addr_max mod_tree.addr_max | |
162 | ||
163 | static noinline void __mod_tree_insert(struct mod_tree_node *node) | |
164 | { | |
165 | latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops); | |
166 | } | |
167 | ||
168 | static void __mod_tree_remove(struct mod_tree_node *node) | |
169 | { | |
170 | latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops); | |
171 | } | |
93c2e105 PZ |
172 | |
173 | /* | |
174 | * These modifications: insert, remove_init and remove; are serialized by the | |
175 | * module_mutex. | |
176 | */ | |
177 | static void mod_tree_insert(struct module *mod) | |
178 | { | |
7523e4dc RR |
179 | mod->core_layout.mtn.mod = mod; |
180 | mod->init_layout.mtn.mod = mod; | |
93c2e105 | 181 | |
7523e4dc RR |
182 | __mod_tree_insert(&mod->core_layout.mtn); |
183 | if (mod->init_layout.size) | |
184 | __mod_tree_insert(&mod->init_layout.mtn); | |
93c2e105 PZ |
185 | } |
186 | ||
187 | static void mod_tree_remove_init(struct module *mod) | |
188 | { | |
7523e4dc RR |
189 | if (mod->init_layout.size) |
190 | __mod_tree_remove(&mod->init_layout.mtn); | |
93c2e105 PZ |
191 | } |
192 | ||
193 | static void mod_tree_remove(struct module *mod) | |
194 | { | |
7523e4dc | 195 | __mod_tree_remove(&mod->core_layout.mtn); |
93c2e105 PZ |
196 | mod_tree_remove_init(mod); |
197 | } | |
198 | ||
6c9692e2 | 199 | static struct module *mod_find(unsigned long addr) |
93c2e105 PZ |
200 | { |
201 | struct latch_tree_node *ltn; | |
202 | ||
4f666546 | 203 | ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops); |
93c2e105 PZ |
204 | if (!ltn) |
205 | return NULL; | |
206 | ||
207 | return container_of(ltn, struct mod_tree_node, node)->mod; | |
208 | } | |
209 | ||
6c9692e2 PZ |
210 | #else /* MODULES_TREE_LOOKUP */ |
211 | ||
4f666546 PZ |
212 | static unsigned long module_addr_min = -1UL, module_addr_max = 0; |
213 | ||
6c9692e2 PZ |
214 | static void mod_tree_insert(struct module *mod) { } |
215 | static void mod_tree_remove_init(struct module *mod) { } | |
216 | static void mod_tree_remove(struct module *mod) { } | |
217 | ||
218 | static struct module *mod_find(unsigned long addr) | |
219 | { | |
220 | struct module *mod; | |
221 | ||
bf08949c MH |
222 | list_for_each_entry_rcu(mod, &modules, list, |
223 | lockdep_is_held(&module_mutex)) { | |
6c9692e2 PZ |
224 | if (within_module(addr, mod)) |
225 | return mod; | |
226 | } | |
227 | ||
228 | return NULL; | |
229 | } | |
230 | ||
231 | #endif /* MODULES_TREE_LOOKUP */ | |
232 | ||
4f666546 PZ |
233 | /* |
234 | * Bounds of module text, for speeding up __module_address. | |
235 | * Protected by module_mutex. | |
236 | */ | |
237 | static void __mod_update_bounds(void *base, unsigned int size) | |
238 | { | |
239 | unsigned long min = (unsigned long)base; | |
240 | unsigned long max = min + size; | |
241 | ||
242 | if (min < module_addr_min) | |
243 | module_addr_min = min; | |
244 | if (max > module_addr_max) | |
245 | module_addr_max = max; | |
246 | } | |
247 | ||
248 | static void mod_update_bounds(struct module *mod) | |
249 | { | |
7523e4dc RR |
250 | __mod_update_bounds(mod->core_layout.base, mod->core_layout.size); |
251 | if (mod->init_layout.size) | |
252 | __mod_update_bounds(mod->init_layout.base, mod->init_layout.size); | |
4f666546 PZ |
253 | } |
254 | ||
67fc4e0c JW |
255 | #ifdef CONFIG_KGDB_KDB |
256 | struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ | |
257 | #endif /* CONFIG_KGDB_KDB */ | |
258 | ||
0be964be PZ |
259 | static void module_assert_mutex(void) |
260 | { | |
261 | lockdep_assert_held(&module_mutex); | |
262 | } | |
263 | ||
264 | static void module_assert_mutex_or_preempt(void) | |
265 | { | |
266 | #ifdef CONFIG_LOCKDEP | |
267 | if (unlikely(!debug_locks)) | |
268 | return; | |
269 | ||
9502514f | 270 | WARN_ON_ONCE(!rcu_read_lock_sched_held() && |
0be964be PZ |
271 | !lockdep_is_held(&module_mutex)); |
272 | #endif | |
273 | } | |
274 | ||
6727bb9c | 275 | static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE); |
106a4ee2 | 276 | module_param(sig_enforce, bool_enable_only, 0644); |
1da177e4 | 277 | |
fda784e5 BM |
278 | /* |
279 | * Export sig_enforce kernel cmdline parameter to allow other subsystems rely | |
280 | * on that instead of directly to CONFIG_MODULE_SIG_FORCE config. | |
281 | */ | |
282 | bool is_module_sig_enforced(void) | |
283 | { | |
284 | return sig_enforce; | |
285 | } | |
286 | EXPORT_SYMBOL(is_module_sig_enforced); | |
287 | ||
8db5da0b MZ |
288 | void set_module_sig_enforced(void) |
289 | { | |
290 | sig_enforce = true; | |
291 | } | |
292 | ||
19e4529e SR |
293 | /* Block module loading/unloading? */ |
294 | int modules_disabled = 0; | |
02608bef | 295 | core_param(nomodule, modules_disabled, bint, 0); |
19e4529e | 296 | |
c9a3ba55 RR |
297 | /* Waiting for a module to finish initializing? */ |
298 | static DECLARE_WAIT_QUEUE_HEAD(module_wq); | |
299 | ||
e041c683 | 300 | static BLOCKING_NOTIFIER_HEAD(module_notify_list); |
1da177e4 | 301 | |
6da0b565 | 302 | int register_module_notifier(struct notifier_block *nb) |
1da177e4 | 303 | { |
e041c683 | 304 | return blocking_notifier_chain_register(&module_notify_list, nb); |
1da177e4 LT |
305 | } |
306 | EXPORT_SYMBOL(register_module_notifier); | |
307 | ||
6da0b565 | 308 | int unregister_module_notifier(struct notifier_block *nb) |
1da177e4 | 309 | { |
e041c683 | 310 | return blocking_notifier_chain_unregister(&module_notify_list, nb); |
1da177e4 LT |
311 | } |
312 | EXPORT_SYMBOL(unregister_module_notifier); | |
313 | ||
71d9f507 MB |
314 | /* |
315 | * We require a truly strong try_module_get(): 0 means success. | |
316 | * Otherwise an error is returned due to ongoing or failed | |
317 | * initialization etc. | |
318 | */ | |
1da177e4 LT |
319 | static inline int strong_try_module_get(struct module *mod) |
320 | { | |
0d21b0e3 | 321 | BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED); |
1da177e4 | 322 | if (mod && mod->state == MODULE_STATE_COMING) |
c9a3ba55 RR |
323 | return -EBUSY; |
324 | if (try_module_get(mod)) | |
1da177e4 | 325 | return 0; |
c9a3ba55 RR |
326 | else |
327 | return -ENOENT; | |
1da177e4 LT |
328 | } |
329 | ||
373d4d09 RR |
330 | static inline void add_taint_module(struct module *mod, unsigned flag, |
331 | enum lockdep_ok lockdep_ok) | |
fa3ba2e8 | 332 | { |
373d4d09 | 333 | add_taint(flag, lockdep_ok); |
7fd8329b | 334 | set_bit(flag, &mod->taints); |
fa3ba2e8 FM |
335 | } |
336 | ||
02a3e59a RD |
337 | /* |
338 | * A thread that wants to hold a reference to a module only while it | |
339 | * is running can call this to safely exit. nfsd and lockd use this. | |
1da177e4 | 340 | */ |
bf262dce | 341 | void __noreturn __module_put_and_exit(struct module *mod, long code) |
1da177e4 LT |
342 | { |
343 | module_put(mod); | |
344 | do_exit(code); | |
345 | } | |
346 | EXPORT_SYMBOL(__module_put_and_exit); | |
22a8bdeb | 347 | |
1da177e4 | 348 | /* Find a module section: 0 means not found. */ |
49668688 | 349 | static unsigned int find_sec(const struct load_info *info, const char *name) |
1da177e4 LT |
350 | { |
351 | unsigned int i; | |
352 | ||
49668688 RR |
353 | for (i = 1; i < info->hdr->e_shnum; i++) { |
354 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
1da177e4 | 355 | /* Alloc bit cleared means "ignore it." */ |
49668688 RR |
356 | if ((shdr->sh_flags & SHF_ALLOC) |
357 | && strcmp(info->secstrings + shdr->sh_name, name) == 0) | |
1da177e4 | 358 | return i; |
49668688 | 359 | } |
1da177e4 LT |
360 | return 0; |
361 | } | |
362 | ||
5e458cc0 | 363 | /* Find a module section, or NULL. */ |
49668688 | 364 | static void *section_addr(const struct load_info *info, const char *name) |
5e458cc0 RR |
365 | { |
366 | /* Section 0 has sh_addr 0. */ | |
49668688 | 367 | return (void *)info->sechdrs[find_sec(info, name)].sh_addr; |
5e458cc0 RR |
368 | } |
369 | ||
370 | /* Find a module section, or NULL. Fill in number of "objects" in section. */ | |
49668688 | 371 | static void *section_objs(const struct load_info *info, |
5e458cc0 RR |
372 | const char *name, |
373 | size_t object_size, | |
374 | unsigned int *num) | |
375 | { | |
49668688 | 376 | unsigned int sec = find_sec(info, name); |
5e458cc0 RR |
377 | |
378 | /* Section 0 has sh_addr 0 and sh_size 0. */ | |
49668688 RR |
379 | *num = info->sechdrs[sec].sh_size / object_size; |
380 | return (void *)info->sechdrs[sec].sh_addr; | |
5e458cc0 RR |
381 | } |
382 | ||
36e68442 AN |
383 | /* Find a module section: 0 means not found. Ignores SHF_ALLOC flag. */ |
384 | static unsigned int find_any_sec(const struct load_info *info, const char *name) | |
385 | { | |
386 | unsigned int i; | |
387 | ||
388 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
389 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
390 | if (strcmp(info->secstrings + shdr->sh_name, name) == 0) | |
391 | return i; | |
392 | } | |
393 | return 0; | |
394 | } | |
395 | ||
396 | /* | |
397 | * Find a module section, or NULL. Fill in number of "objects" in section. | |
398 | * Ignores SHF_ALLOC flag. | |
399 | */ | |
400 | static __maybe_unused void *any_section_objs(const struct load_info *info, | |
401 | const char *name, | |
402 | size_t object_size, | |
403 | unsigned int *num) | |
404 | { | |
405 | unsigned int sec = find_any_sec(info, name); | |
406 | ||
407 | /* Section 0 has sh_addr 0 and sh_size 0. */ | |
408 | *num = info->sechdrs[sec].sh_size / object_size; | |
409 | return (void *)info->sechdrs[sec].sh_addr; | |
410 | } | |
411 | ||
1da177e4 LT |
412 | /* Provided by the linker */ |
413 | extern const struct kernel_symbol __start___ksymtab[]; | |
414 | extern const struct kernel_symbol __stop___ksymtab[]; | |
415 | extern const struct kernel_symbol __start___ksymtab_gpl[]; | |
416 | extern const struct kernel_symbol __stop___ksymtab_gpl[]; | |
9f28bb7e GKH |
417 | extern const struct kernel_symbol __start___ksymtab_gpl_future[]; |
418 | extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; | |
71810db2 AB |
419 | extern const s32 __start___kcrctab[]; |
420 | extern const s32 __start___kcrctab_gpl[]; | |
421 | extern const s32 __start___kcrctab_gpl_future[]; | |
f7f5b675 DV |
422 | #ifdef CONFIG_UNUSED_SYMBOLS |
423 | extern const struct kernel_symbol __start___ksymtab_unused[]; | |
424 | extern const struct kernel_symbol __stop___ksymtab_unused[]; | |
425 | extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; | |
426 | extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; | |
71810db2 AB |
427 | extern const s32 __start___kcrctab_unused[]; |
428 | extern const s32 __start___kcrctab_unused_gpl[]; | |
f7f5b675 | 429 | #endif |
1da177e4 LT |
430 | |
431 | #ifndef CONFIG_MODVERSIONS | |
432 | #define symversion(base, idx) NULL | |
433 | #else | |
f83ca9fe | 434 | #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL) |
1da177e4 LT |
435 | #endif |
436 | ||
dafd0940 RR |
437 | static bool each_symbol_in_section(const struct symsearch *arr, |
438 | unsigned int arrsize, | |
439 | struct module *owner, | |
440 | bool (*fn)(const struct symsearch *syms, | |
441 | struct module *owner, | |
de4d8d53 | 442 | void *data), |
dafd0940 | 443 | void *data) |
ad9546c9 | 444 | { |
de4d8d53 | 445 | unsigned int j; |
ad9546c9 | 446 | |
dafd0940 | 447 | for (j = 0; j < arrsize; j++) { |
de4d8d53 RR |
448 | if (fn(&arr[j], owner, data)) |
449 | return true; | |
f71d20e9 | 450 | } |
dafd0940 RR |
451 | |
452 | return false; | |
ad9546c9 RR |
453 | } |
454 | ||
dafd0940 | 455 | /* Returns true as soon as fn returns true, otherwise false. */ |
a54e0491 | 456 | static bool each_symbol_section(bool (*fn)(const struct symsearch *arr, |
de4d8d53 RR |
457 | struct module *owner, |
458 | void *data), | |
459 | void *data) | |
ad9546c9 RR |
460 | { |
461 | struct module *mod; | |
44032e63 | 462 | static const struct symsearch arr[] = { |
ad9546c9 | 463 | { __start___ksymtab, __stop___ksymtab, __start___kcrctab, |
dafd0940 | 464 | NOT_GPL_ONLY, false }, |
ad9546c9 | 465 | { __start___ksymtab_gpl, __stop___ksymtab_gpl, |
dafd0940 RR |
466 | __start___kcrctab_gpl, |
467 | GPL_ONLY, false }, | |
ad9546c9 | 468 | { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future, |
dafd0940 RR |
469 | __start___kcrctab_gpl_future, |
470 | WILL_BE_GPL_ONLY, false }, | |
f7f5b675 | 471 | #ifdef CONFIG_UNUSED_SYMBOLS |
ad9546c9 | 472 | { __start___ksymtab_unused, __stop___ksymtab_unused, |
dafd0940 RR |
473 | __start___kcrctab_unused, |
474 | NOT_GPL_ONLY, true }, | |
ad9546c9 | 475 | { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl, |
dafd0940 RR |
476 | __start___kcrctab_unused_gpl, |
477 | GPL_ONLY, true }, | |
f7f5b675 | 478 | #endif |
ad9546c9 | 479 | }; |
f71d20e9 | 480 | |
0be964be PZ |
481 | module_assert_mutex_or_preempt(); |
482 | ||
dafd0940 RR |
483 | if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data)) |
484 | return true; | |
f71d20e9 | 485 | |
bf08949c MH |
486 | list_for_each_entry_rcu(mod, &modules, list, |
487 | lockdep_is_held(&module_mutex)) { | |
ad9546c9 RR |
488 | struct symsearch arr[] = { |
489 | { mod->syms, mod->syms + mod->num_syms, mod->crcs, | |
dafd0940 | 490 | NOT_GPL_ONLY, false }, |
ad9546c9 | 491 | { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, |
dafd0940 RR |
492 | mod->gpl_crcs, |
493 | GPL_ONLY, false }, | |
ad9546c9 RR |
494 | { mod->gpl_future_syms, |
495 | mod->gpl_future_syms + mod->num_gpl_future_syms, | |
dafd0940 RR |
496 | mod->gpl_future_crcs, |
497 | WILL_BE_GPL_ONLY, false }, | |
f7f5b675 | 498 | #ifdef CONFIG_UNUSED_SYMBOLS |
ad9546c9 RR |
499 | { mod->unused_syms, |
500 | mod->unused_syms + mod->num_unused_syms, | |
dafd0940 RR |
501 | mod->unused_crcs, |
502 | NOT_GPL_ONLY, true }, | |
ad9546c9 RR |
503 | { mod->unused_gpl_syms, |
504 | mod->unused_gpl_syms + mod->num_unused_gpl_syms, | |
dafd0940 RR |
505 | mod->unused_gpl_crcs, |
506 | GPL_ONLY, true }, | |
f7f5b675 | 507 | #endif |
ad9546c9 RR |
508 | }; |
509 | ||
0d21b0e3 RR |
510 | if (mod->state == MODULE_STATE_UNFORMED) |
511 | continue; | |
512 | ||
dafd0940 RR |
513 | if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data)) |
514 | return true; | |
515 | } | |
516 | return false; | |
517 | } | |
518 | ||
519 | struct find_symbol_arg { | |
520 | /* Input */ | |
521 | const char *name; | |
522 | bool gplok; | |
523 | bool warn; | |
524 | ||
525 | /* Output */ | |
526 | struct module *owner; | |
71810db2 | 527 | const s32 *crc; |
414fd31b | 528 | const struct kernel_symbol *sym; |
ef1dac60 | 529 | enum mod_license license; |
dafd0940 RR |
530 | }; |
531 | ||
2d25bc55 JY |
532 | static bool check_exported_symbol(const struct symsearch *syms, |
533 | struct module *owner, | |
534 | unsigned int symnum, void *data) | |
dafd0940 RR |
535 | { |
536 | struct find_symbol_arg *fsa = data; | |
537 | ||
dafd0940 | 538 | if (!fsa->gplok) { |
cd8732cd | 539 | if (syms->license == GPL_ONLY) |
dafd0940 | 540 | return false; |
cd8732cd | 541 | if (syms->license == WILL_BE_GPL_ONLY && fsa->warn) { |
bddb12b3 AM |
542 | pr_warn("Symbol %s is being used by a non-GPL module, " |
543 | "which will not be allowed in the future\n", | |
544 | fsa->name); | |
9f28bb7e | 545 | } |
1da177e4 | 546 | } |
ad9546c9 | 547 | |
f7f5b675 | 548 | #ifdef CONFIG_UNUSED_SYMBOLS |
dafd0940 | 549 | if (syms->unused && fsa->warn) { |
bddb12b3 AM |
550 | pr_warn("Symbol %s is marked as UNUSED, however this module is " |
551 | "using it.\n", fsa->name); | |
552 | pr_warn("This symbol will go away in the future.\n"); | |
7b63c3ab YG |
553 | pr_warn("Please evaluate if this is the right api to use and " |
554 | "if it really is, submit a report to the linux kernel " | |
555 | "mailing list together with submitting your code for " | |
bddb12b3 | 556 | "inclusion.\n"); |
dafd0940 | 557 | } |
f7f5b675 | 558 | #endif |
dafd0940 RR |
559 | |
560 | fsa->owner = owner; | |
561 | fsa->crc = symversion(syms->crcs, symnum); | |
414fd31b | 562 | fsa->sym = &syms->start[symnum]; |
ef1dac60 | 563 | fsa->license = syms->license; |
dafd0940 RR |
564 | return true; |
565 | } | |
566 | ||
7290d580 AB |
567 | static unsigned long kernel_symbol_value(const struct kernel_symbol *sym) |
568 | { | |
569 | #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS | |
570 | return (unsigned long)offset_to_ptr(&sym->value_offset); | |
571 | #else | |
572 | return sym->value; | |
573 | #endif | |
574 | } | |
575 | ||
576 | static const char *kernel_symbol_name(const struct kernel_symbol *sym) | |
577 | { | |
578 | #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS | |
579 | return offset_to_ptr(&sym->name_offset); | |
580 | #else | |
581 | return sym->name; | |
582 | #endif | |
583 | } | |
584 | ||
8651ec01 MM |
585 | static const char *kernel_symbol_namespace(const struct kernel_symbol *sym) |
586 | { | |
587 | #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS | |
069e1c07 WD |
588 | if (!sym->namespace_offset) |
589 | return NULL; | |
8651ec01 MM |
590 | return offset_to_ptr(&sym->namespace_offset); |
591 | #else | |
592 | return sym->namespace; | |
593 | #endif | |
594 | } | |
595 | ||
b605be65 | 596 | static int cmp_name(const void *name, const void *sym) |
403ed278 | 597 | { |
b605be65 | 598 | return strcmp(name, kernel_symbol_name(sym)); |
403ed278 AIB |
599 | } |
600 | ||
2d25bc55 JY |
601 | static bool find_exported_symbol_in_section(const struct symsearch *syms, |
602 | struct module *owner, | |
603 | void *data) | |
de4d8d53 RR |
604 | { |
605 | struct find_symbol_arg *fsa = data; | |
403ed278 AIB |
606 | struct kernel_symbol *sym; |
607 | ||
608 | sym = bsearch(fsa->name, syms->start, syms->stop - syms->start, | |
609 | sizeof(struct kernel_symbol), cmp_name); | |
610 | ||
2d25bc55 JY |
611 | if (sym != NULL && check_exported_symbol(syms, owner, |
612 | sym - syms->start, data)) | |
403ed278 | 613 | return true; |
de4d8d53 | 614 | |
de4d8d53 RR |
615 | return false; |
616 | } | |
617 | ||
24b9f0d2 SS |
618 | /* |
619 | * Find an exported symbol and return it, along with, (optional) crc and | |
620 | * (optional) module which owns it. Needs preempt disabled or module_mutex. | |
621 | */ | |
77311047 | 622 | static const struct kernel_symbol *find_symbol(const char *name, |
c6b37801 | 623 | struct module **owner, |
71810db2 | 624 | const s32 **crc, |
ef1dac60 | 625 | enum mod_license *license, |
c6b37801 TA |
626 | bool gplok, |
627 | bool warn) | |
dafd0940 RR |
628 | { |
629 | struct find_symbol_arg fsa; | |
630 | ||
631 | fsa.name = name; | |
632 | fsa.gplok = gplok; | |
633 | fsa.warn = warn; | |
634 | ||
2d25bc55 | 635 | if (each_symbol_section(find_exported_symbol_in_section, &fsa)) { |
dafd0940 RR |
636 | if (owner) |
637 | *owner = fsa.owner; | |
638 | if (crc) | |
639 | *crc = fsa.crc; | |
ef1dac60 CH |
640 | if (license) |
641 | *license = fsa.license; | |
414fd31b | 642 | return fsa.sym; |
dafd0940 RR |
643 | } |
644 | ||
5e124169 | 645 | pr_debug("Failed to find symbol %s\n", name); |
414fd31b | 646 | return NULL; |
1da177e4 LT |
647 | } |
648 | ||
fe0d34d2 RR |
649 | /* |
650 | * Search for module by name: must hold module_mutex (or preempt disabled | |
651 | * for read-only access). | |
652 | */ | |
4f6de4d5 | 653 | static struct module *find_module_all(const char *name, size_t len, |
0d21b0e3 | 654 | bool even_unformed) |
1da177e4 LT |
655 | { |
656 | struct module *mod; | |
657 | ||
fe0d34d2 | 658 | module_assert_mutex_or_preempt(); |
0be964be | 659 | |
bf08949c MH |
660 | list_for_each_entry_rcu(mod, &modules, list, |
661 | lockdep_is_held(&module_mutex)) { | |
0d21b0e3 RR |
662 | if (!even_unformed && mod->state == MODULE_STATE_UNFORMED) |
663 | continue; | |
4f6de4d5 | 664 | if (strlen(mod->name) == len && !memcmp(mod->name, name, len)) |
1da177e4 LT |
665 | return mod; |
666 | } | |
667 | return NULL; | |
668 | } | |
0d21b0e3 RR |
669 | |
670 | struct module *find_module(const char *name) | |
671 | { | |
fe0d34d2 | 672 | module_assert_mutex(); |
4f6de4d5 | 673 | return find_module_all(name, strlen(name), false); |
0d21b0e3 | 674 | } |
c6b37801 | 675 | EXPORT_SYMBOL_GPL(find_module); |
1da177e4 LT |
676 | |
677 | #ifdef CONFIG_SMP | |
fbf59bc9 | 678 | |
259354de | 679 | static inline void __percpu *mod_percpu(struct module *mod) |
fbf59bc9 | 680 | { |
259354de TH |
681 | return mod->percpu; |
682 | } | |
fbf59bc9 | 683 | |
9eb76d77 | 684 | static int percpu_modalloc(struct module *mod, struct load_info *info) |
259354de | 685 | { |
9eb76d77 RR |
686 | Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu]; |
687 | unsigned long align = pcpusec->sh_addralign; | |
688 | ||
689 | if (!pcpusec->sh_size) | |
690 | return 0; | |
691 | ||
fbf59bc9 | 692 | if (align > PAGE_SIZE) { |
bddb12b3 AM |
693 | pr_warn("%s: per-cpu alignment %li > %li\n", |
694 | mod->name, align, PAGE_SIZE); | |
fbf59bc9 TH |
695 | align = PAGE_SIZE; |
696 | } | |
697 | ||
9eb76d77 | 698 | mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align); |
259354de | 699 | if (!mod->percpu) { |
bddb12b3 AM |
700 | pr_warn("%s: Could not allocate %lu bytes percpu data\n", |
701 | mod->name, (unsigned long)pcpusec->sh_size); | |
259354de TH |
702 | return -ENOMEM; |
703 | } | |
9eb76d77 | 704 | mod->percpu_size = pcpusec->sh_size; |
259354de | 705 | return 0; |
fbf59bc9 TH |
706 | } |
707 | ||
259354de | 708 | static void percpu_modfree(struct module *mod) |
fbf59bc9 | 709 | { |
259354de | 710 | free_percpu(mod->percpu); |
fbf59bc9 TH |
711 | } |
712 | ||
49668688 | 713 | static unsigned int find_pcpusec(struct load_info *info) |
6b588c18 | 714 | { |
49668688 | 715 | return find_sec(info, ".data..percpu"); |
6b588c18 TH |
716 | } |
717 | ||
259354de TH |
718 | static void percpu_modcopy(struct module *mod, |
719 | const void *from, unsigned long size) | |
6b588c18 TH |
720 | { |
721 | int cpu; | |
722 | ||
723 | for_each_possible_cpu(cpu) | |
259354de | 724 | memcpy(per_cpu_ptr(mod->percpu, cpu), from, size); |
6b588c18 TH |
725 | } |
726 | ||
383776fa | 727 | bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr) |
10fad5e4 TH |
728 | { |
729 | struct module *mod; | |
730 | unsigned int cpu; | |
731 | ||
732 | preempt_disable(); | |
733 | ||
734 | list_for_each_entry_rcu(mod, &modules, list) { | |
0d21b0e3 RR |
735 | if (mod->state == MODULE_STATE_UNFORMED) |
736 | continue; | |
10fad5e4 TH |
737 | if (!mod->percpu_size) |
738 | continue; | |
739 | for_each_possible_cpu(cpu) { | |
740 | void *start = per_cpu_ptr(mod->percpu, cpu); | |
383776fa | 741 | void *va = (void *)addr; |
10fad5e4 | 742 | |
383776fa | 743 | if (va >= start && va < start + mod->percpu_size) { |
8ce371f9 | 744 | if (can_addr) { |
383776fa | 745 | *can_addr = (unsigned long) (va - start); |
8ce371f9 PZ |
746 | *can_addr += (unsigned long) |
747 | per_cpu_ptr(mod->percpu, | |
748 | get_boot_cpu_id()); | |
749 | } | |
10fad5e4 TH |
750 | preempt_enable(); |
751 | return true; | |
752 | } | |
753 | } | |
754 | } | |
755 | ||
756 | preempt_enable(); | |
757 | return false; | |
6b588c18 TH |
758 | } |
759 | ||
383776fa | 760 | /** |
24389b61 | 761 | * is_module_percpu_address() - test whether address is from module static percpu |
383776fa TG |
762 | * @addr: address to test |
763 | * | |
764 | * Test whether @addr belongs to module static percpu area. | |
765 | * | |
24389b61 | 766 | * Return: %true if @addr is from module static percpu area |
383776fa TG |
767 | */ |
768 | bool is_module_percpu_address(unsigned long addr) | |
769 | { | |
770 | return __is_module_percpu_address(addr, NULL); | |
771 | } | |
772 | ||
1da177e4 | 773 | #else /* ... !CONFIG_SMP */ |
6b588c18 | 774 | |
259354de | 775 | static inline void __percpu *mod_percpu(struct module *mod) |
1da177e4 LT |
776 | { |
777 | return NULL; | |
778 | } | |
9eb76d77 | 779 | static int percpu_modalloc(struct module *mod, struct load_info *info) |
259354de | 780 | { |
9eb76d77 RR |
781 | /* UP modules shouldn't have this section: ENOMEM isn't quite right */ |
782 | if (info->sechdrs[info->index.pcpu].sh_size != 0) | |
783 | return -ENOMEM; | |
784 | return 0; | |
259354de TH |
785 | } |
786 | static inline void percpu_modfree(struct module *mod) | |
1da177e4 | 787 | { |
1da177e4 | 788 | } |
49668688 | 789 | static unsigned int find_pcpusec(struct load_info *info) |
1da177e4 LT |
790 | { |
791 | return 0; | |
792 | } | |
259354de TH |
793 | static inline void percpu_modcopy(struct module *mod, |
794 | const void *from, unsigned long size) | |
1da177e4 LT |
795 | { |
796 | /* pcpusec should be 0, and size of that section should be 0. */ | |
797 | BUG_ON(size != 0); | |
798 | } | |
10fad5e4 TH |
799 | bool is_module_percpu_address(unsigned long addr) |
800 | { | |
801 | return false; | |
802 | } | |
6b588c18 | 803 | |
383776fa TG |
804 | bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr) |
805 | { | |
806 | return false; | |
807 | } | |
808 | ||
1da177e4 LT |
809 | #endif /* CONFIG_SMP */ |
810 | ||
c988d2b2 MD |
811 | #define MODINFO_ATTR(field) \ |
812 | static void setup_modinfo_##field(struct module *mod, const char *s) \ | |
813 | { \ | |
814 | mod->field = kstrdup(s, GFP_KERNEL); \ | |
815 | } \ | |
816 | static ssize_t show_modinfo_##field(struct module_attribute *mattr, \ | |
4befb026 | 817 | struct module_kobject *mk, char *buffer) \ |
c988d2b2 | 818 | { \ |
cc56ded3 | 819 | return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \ |
c988d2b2 MD |
820 | } \ |
821 | static int modinfo_##field##_exists(struct module *mod) \ | |
822 | { \ | |
823 | return mod->field != NULL; \ | |
824 | } \ | |
825 | static void free_modinfo_##field(struct module *mod) \ | |
826 | { \ | |
22a8bdeb DW |
827 | kfree(mod->field); \ |
828 | mod->field = NULL; \ | |
c988d2b2 MD |
829 | } \ |
830 | static struct module_attribute modinfo_##field = { \ | |
7b595756 | 831 | .attr = { .name = __stringify(field), .mode = 0444 }, \ |
c988d2b2 MD |
832 | .show = show_modinfo_##field, \ |
833 | .setup = setup_modinfo_##field, \ | |
834 | .test = modinfo_##field##_exists, \ | |
835 | .free = free_modinfo_##field, \ | |
836 | }; | |
837 | ||
838 | MODINFO_ATTR(version); | |
839 | MODINFO_ATTR(srcversion); | |
840 | ||
e14af7ee AV |
841 | static char last_unloaded_module[MODULE_NAME_LEN+1]; |
842 | ||
03e88ae1 | 843 | #ifdef CONFIG_MODULE_UNLOAD |
eb0c5377 SR |
844 | |
845 | EXPORT_TRACEPOINT_SYMBOL(module_get); | |
846 | ||
e513cc1c MH |
847 | /* MODULE_REF_BASE is the base reference count by kmodule loader. */ |
848 | #define MODULE_REF_BASE 1 | |
849 | ||
1da177e4 | 850 | /* Init the unload section of the module. */ |
9f85a4bb | 851 | static int module_unload_init(struct module *mod) |
1da177e4 | 852 | { |
e513cc1c MH |
853 | /* |
854 | * Initialize reference counter to MODULE_REF_BASE. | |
855 | * refcnt == 0 means module is going. | |
856 | */ | |
857 | atomic_set(&mod->refcnt, MODULE_REF_BASE); | |
9f85a4bb | 858 | |
2c02dfe7 LT |
859 | INIT_LIST_HEAD(&mod->source_list); |
860 | INIT_LIST_HEAD(&mod->target_list); | |
e1783a24 | 861 | |
1da177e4 | 862 | /* Hold reference count during initialization. */ |
e513cc1c | 863 | atomic_inc(&mod->refcnt); |
9f85a4bb RR |
864 | |
865 | return 0; | |
1da177e4 LT |
866 | } |
867 | ||
1da177e4 LT |
868 | /* Does a already use b? */ |
869 | static int already_uses(struct module *a, struct module *b) | |
870 | { | |
871 | struct module_use *use; | |
872 | ||
2c02dfe7 LT |
873 | list_for_each_entry(use, &b->source_list, source_list) { |
874 | if (use->source == a) { | |
5e124169 | 875 | pr_debug("%s uses %s!\n", a->name, b->name); |
1da177e4 LT |
876 | return 1; |
877 | } | |
878 | } | |
5e124169 | 879 | pr_debug("%s does not use %s!\n", a->name, b->name); |
1da177e4 LT |
880 | return 0; |
881 | } | |
882 | ||
2c02dfe7 LT |
883 | /* |
884 | * Module a uses b | |
885 | * - we add 'a' as a "source", 'b' as a "target" of module use | |
886 | * - the module_use is added to the list of 'b' sources (so | |
887 | * 'b' can walk the list to see who sourced them), and of 'a' | |
888 | * targets (so 'a' can see what modules it targets). | |
889 | */ | |
890 | static int add_module_usage(struct module *a, struct module *b) | |
891 | { | |
2c02dfe7 LT |
892 | struct module_use *use; |
893 | ||
5e124169 | 894 | pr_debug("Allocating new usage for %s.\n", a->name); |
2c02dfe7 | 895 | use = kmalloc(sizeof(*use), GFP_ATOMIC); |
9ad04574 | 896 | if (!use) |
2c02dfe7 | 897 | return -ENOMEM; |
2c02dfe7 LT |
898 | |
899 | use->source = a; | |
900 | use->target = b; | |
901 | list_add(&use->source_list, &b->source_list); | |
902 | list_add(&use->target_list, &a->target_list); | |
2c02dfe7 LT |
903 | return 0; |
904 | } | |
905 | ||
75676500 | 906 | /* Module a uses b: caller needs module_mutex() */ |
7ef5264d | 907 | static int ref_module(struct module *a, struct module *b) |
1da177e4 | 908 | { |
c8e21ced | 909 | int err; |
270a6c4c | 910 | |
9bea7f23 | 911 | if (b == NULL || already_uses(a, b)) |
218ce735 | 912 | return 0; |
218ce735 | 913 | |
9bea7f23 RR |
914 | /* If module isn't available, we fail. */ |
915 | err = strong_try_module_get(b); | |
c9a3ba55 | 916 | if (err) |
9bea7f23 | 917 | return err; |
1da177e4 | 918 | |
2c02dfe7 LT |
919 | err = add_module_usage(a, b); |
920 | if (err) { | |
1da177e4 | 921 | module_put(b); |
9bea7f23 | 922 | return err; |
1da177e4 | 923 | } |
9bea7f23 | 924 | return 0; |
1da177e4 LT |
925 | } |
926 | ||
927 | /* Clear the unload stuff of the module. */ | |
928 | static void module_unload_free(struct module *mod) | |
929 | { | |
2c02dfe7 | 930 | struct module_use *use, *tmp; |
1da177e4 | 931 | |
75676500 | 932 | mutex_lock(&module_mutex); |
2c02dfe7 LT |
933 | list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) { |
934 | struct module *i = use->target; | |
5e124169 | 935 | pr_debug("%s unusing %s\n", mod->name, i->name); |
2c02dfe7 LT |
936 | module_put(i); |
937 | list_del(&use->source_list); | |
938 | list_del(&use->target_list); | |
939 | kfree(use); | |
1da177e4 | 940 | } |
75676500 | 941 | mutex_unlock(&module_mutex); |
1da177e4 LT |
942 | } |
943 | ||
944 | #ifdef CONFIG_MODULE_FORCE_UNLOAD | |
fb169793 | 945 | static inline int try_force_unload(unsigned int flags) |
1da177e4 LT |
946 | { |
947 | int ret = (flags & O_TRUNC); | |
948 | if (ret) | |
373d4d09 | 949 | add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE); |
1da177e4 LT |
950 | return ret; |
951 | } | |
952 | #else | |
fb169793 | 953 | static inline int try_force_unload(unsigned int flags) |
1da177e4 LT |
954 | { |
955 | return 0; | |
956 | } | |
957 | #endif /* CONFIG_MODULE_FORCE_UNLOAD */ | |
958 | ||
e513cc1c MH |
959 | /* Try to release refcount of module, 0 means success. */ |
960 | static int try_release_module_ref(struct module *mod) | |
1da177e4 | 961 | { |
e513cc1c | 962 | int ret; |
1da177e4 | 963 | |
e513cc1c MH |
964 | /* Try to decrement refcnt which we set at loading */ |
965 | ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt); | |
966 | BUG_ON(ret < 0); | |
967 | if (ret) | |
968 | /* Someone can put this right now, recover with checking */ | |
969 | ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0); | |
1da177e4 | 970 | |
e513cc1c MH |
971 | return ret; |
972 | } | |
1da177e4 | 973 | |
e513cc1c MH |
974 | static int try_stop_module(struct module *mod, int flags, int *forced) |
975 | { | |
da39ba5e | 976 | /* If it's not unused, quit unless we're forcing. */ |
e513cc1c MH |
977 | if (try_release_module_ref(mod) != 0) { |
978 | *forced = try_force_unload(flags); | |
979 | if (!(*forced)) | |
1da177e4 LT |
980 | return -EWOULDBLOCK; |
981 | } | |
982 | ||
983 | /* Mark it as dying. */ | |
e513cc1c | 984 | mod->state = MODULE_STATE_GOING; |
1da177e4 | 985 | |
e513cc1c | 986 | return 0; |
1da177e4 LT |
987 | } |
988 | ||
d5db139a | 989 | /** |
24389b61 | 990 | * module_refcount() - return the refcount or -1 if unloading |
d5db139a RR |
991 | * @mod: the module we're checking |
992 | * | |
24389b61 | 993 | * Return: |
d5db139a RR |
994 | * -1 if the module is in the process of unloading |
995 | * otherwise the number of references in the kernel to the module | |
996 | */ | |
997 | int module_refcount(struct module *mod) | |
1da177e4 | 998 | { |
d5db139a | 999 | return atomic_read(&mod->refcnt) - MODULE_REF_BASE; |
1da177e4 LT |
1000 | } |
1001 | EXPORT_SYMBOL(module_refcount); | |
1002 | ||
1003 | /* This exists whether we can unload or not */ | |
1004 | static void free_module(struct module *mod); | |
1005 | ||
17da2bd9 HC |
1006 | SYSCALL_DEFINE2(delete_module, const char __user *, name_user, |
1007 | unsigned int, flags) | |
1da177e4 LT |
1008 | { |
1009 | struct module *mod; | |
dfff0a06 | 1010 | char name[MODULE_NAME_LEN]; |
1da177e4 LT |
1011 | int ret, forced = 0; |
1012 | ||
3d43321b | 1013 | if (!capable(CAP_SYS_MODULE) || modules_disabled) |
dfff0a06 GKH |
1014 | return -EPERM; |
1015 | ||
1016 | if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) | |
1017 | return -EFAULT; | |
1018 | name[MODULE_NAME_LEN-1] = '\0'; | |
1019 | ||
f6276ac9 RGB |
1020 | audit_log_kern_module(name); |
1021 | ||
3fc1f1e2 TH |
1022 | if (mutex_lock_interruptible(&module_mutex) != 0) |
1023 | return -EINTR; | |
1da177e4 LT |
1024 | |
1025 | mod = find_module(name); | |
1026 | if (!mod) { | |
1027 | ret = -ENOENT; | |
1028 | goto out; | |
1029 | } | |
1030 | ||
2c02dfe7 | 1031 | if (!list_empty(&mod->source_list)) { |
1da177e4 LT |
1032 | /* Other modules depend on us: get rid of them first. */ |
1033 | ret = -EWOULDBLOCK; | |
1034 | goto out; | |
1035 | } | |
1036 | ||
1037 | /* Doing init or already dying? */ | |
1038 | if (mod->state != MODULE_STATE_LIVE) { | |
3f2b9c9c | 1039 | /* FIXME: if (force), slam module count damn the torpedoes */ |
5e124169 | 1040 | pr_debug("%s already dying\n", mod->name); |
1da177e4 LT |
1041 | ret = -EBUSY; |
1042 | goto out; | |
1043 | } | |
1044 | ||
1045 | /* If it has an init func, it must have an exit func to unload */ | |
af49d924 | 1046 | if (mod->init && !mod->exit) { |
fb169793 | 1047 | forced = try_force_unload(flags); |
1da177e4 LT |
1048 | if (!forced) { |
1049 | /* This module can't be removed */ | |
1050 | ret = -EBUSY; | |
1051 | goto out; | |
1052 | } | |
1053 | } | |
1054 | ||
1da177e4 LT |
1055 | /* Stop the machine so refcounts can't move and disable module. */ |
1056 | ret = try_stop_module(mod, flags, &forced); | |
1057 | if (ret != 0) | |
1058 | goto out; | |
1059 | ||
df4b565e | 1060 | mutex_unlock(&module_mutex); |
25985edc | 1061 | /* Final destruction now no one is using it. */ |
df4b565e | 1062 | if (mod->exit != NULL) |
1da177e4 | 1063 | mod->exit(); |
df4b565e PO |
1064 | blocking_notifier_call_chain(&module_notify_list, |
1065 | MODULE_STATE_GOING, mod); | |
7e545d6e | 1066 | klp_module_going(mod); |
7dcd182b JY |
1067 | ftrace_release_mod(mod); |
1068 | ||
22a9d645 | 1069 | async_synchronize_full(); |
75676500 | 1070 | |
e14af7ee | 1071 | /* Store the name of the last unloaded module for diagnostic purposes */ |
efa5345e | 1072 | strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); |
1da177e4 | 1073 | |
75676500 | 1074 | free_module(mod); |
5d603311 KK |
1075 | /* someone could wait for the module in add_unformed_module() */ |
1076 | wake_up_all(&module_wq); | |
75676500 RR |
1077 | return 0; |
1078 | out: | |
6389a385 | 1079 | mutex_unlock(&module_mutex); |
1da177e4 LT |
1080 | return ret; |
1081 | } | |
1082 | ||
d1e99d7a | 1083 | static inline void print_unload_info(struct seq_file *m, struct module *mod) |
1da177e4 LT |
1084 | { |
1085 | struct module_use *use; | |
1086 | int printed_something = 0; | |
1087 | ||
d5db139a | 1088 | seq_printf(m, " %i ", module_refcount(mod)); |
1da177e4 | 1089 | |
6da0b565 IA |
1090 | /* |
1091 | * Always include a trailing , so userspace can differentiate | |
1092 | * between this and the old multi-field proc format. | |
1093 | */ | |
2c02dfe7 | 1094 | list_for_each_entry(use, &mod->source_list, source_list) { |
1da177e4 | 1095 | printed_something = 1; |
2c02dfe7 | 1096 | seq_printf(m, "%s,", use->source->name); |
1da177e4 LT |
1097 | } |
1098 | ||
1da177e4 LT |
1099 | if (mod->init != NULL && mod->exit == NULL) { |
1100 | printed_something = 1; | |
6da0b565 | 1101 | seq_puts(m, "[permanent],"); |
1da177e4 LT |
1102 | } |
1103 | ||
1104 | if (!printed_something) | |
6da0b565 | 1105 | seq_puts(m, "-"); |
1da177e4 LT |
1106 | } |
1107 | ||
1108 | void __symbol_put(const char *symbol) | |
1109 | { | |
1110 | struct module *owner; | |
1da177e4 | 1111 | |
24da1cbf | 1112 | preempt_disable(); |
ef1dac60 | 1113 | if (!find_symbol(symbol, &owner, NULL, NULL, true, false)) |
1da177e4 LT |
1114 | BUG(); |
1115 | module_put(owner); | |
24da1cbf | 1116 | preempt_enable(); |
1da177e4 LT |
1117 | } |
1118 | EXPORT_SYMBOL(__symbol_put); | |
1119 | ||
7d1d16e4 | 1120 | /* Note this assumes addr is a function, which it currently always is. */ |
1da177e4 LT |
1121 | void symbol_put_addr(void *addr) |
1122 | { | |
5e376613 | 1123 | struct module *modaddr; |
7d1d16e4 | 1124 | unsigned long a = (unsigned long)dereference_function_descriptor(addr); |
1da177e4 | 1125 | |
7d1d16e4 | 1126 | if (core_kernel_text(a)) |
5e376613 | 1127 | return; |
1da177e4 | 1128 | |
275d7d44 PZ |
1129 | /* |
1130 | * Even though we hold a reference on the module; we still need to | |
1131 | * disable preemption in order to safely traverse the data structure. | |
1132 | */ | |
1133 | preempt_disable(); | |
7d1d16e4 | 1134 | modaddr = __module_text_address(a); |
a6e6abd5 | 1135 | BUG_ON(!modaddr); |
5e376613 | 1136 | module_put(modaddr); |
275d7d44 | 1137 | preempt_enable(); |
1da177e4 LT |
1138 | } |
1139 | EXPORT_SYMBOL_GPL(symbol_put_addr); | |
1140 | ||
1141 | static ssize_t show_refcnt(struct module_attribute *mattr, | |
4befb026 | 1142 | struct module_kobject *mk, char *buffer) |
1da177e4 | 1143 | { |
d5db139a | 1144 | return sprintf(buffer, "%i\n", module_refcount(mk->mod)); |
1da177e4 LT |
1145 | } |
1146 | ||
cca3e707 KS |
1147 | static struct module_attribute modinfo_refcnt = |
1148 | __ATTR(refcnt, 0444, show_refcnt, NULL); | |
1da177e4 | 1149 | |
d53799be SR |
1150 | void __module_get(struct module *module) |
1151 | { | |
1152 | if (module) { | |
1153 | preempt_disable(); | |
2f35c41f | 1154 | atomic_inc(&module->refcnt); |
d53799be SR |
1155 | trace_module_get(module, _RET_IP_); |
1156 | preempt_enable(); | |
1157 | } | |
1158 | } | |
1159 | EXPORT_SYMBOL(__module_get); | |
1160 | ||
1161 | bool try_module_get(struct module *module) | |
1162 | { | |
1163 | bool ret = true; | |
1164 | ||
1165 | if (module) { | |
1166 | preempt_disable(); | |
e513cc1c MH |
1167 | /* Note: here, we can fail to get a reference */ |
1168 | if (likely(module_is_live(module) && | |
1169 | atomic_inc_not_zero(&module->refcnt) != 0)) | |
d53799be | 1170 | trace_module_get(module, _RET_IP_); |
e513cc1c | 1171 | else |
d53799be SR |
1172 | ret = false; |
1173 | ||
1174 | preempt_enable(); | |
1175 | } | |
1176 | return ret; | |
1177 | } | |
1178 | EXPORT_SYMBOL(try_module_get); | |
1179 | ||
f6a57033 AV |
1180 | void module_put(struct module *module) |
1181 | { | |
e513cc1c MH |
1182 | int ret; |
1183 | ||
f6a57033 | 1184 | if (module) { |
e1783a24 | 1185 | preempt_disable(); |
e513cc1c MH |
1186 | ret = atomic_dec_if_positive(&module->refcnt); |
1187 | WARN_ON(ret < 0); /* Failed to put refcount */ | |
ae832d1e | 1188 | trace_module_put(module, _RET_IP_); |
e1783a24 | 1189 | preempt_enable(); |
f6a57033 AV |
1190 | } |
1191 | } | |
1192 | EXPORT_SYMBOL(module_put); | |
1193 | ||
1da177e4 | 1194 | #else /* !CONFIG_MODULE_UNLOAD */ |
d1e99d7a | 1195 | static inline void print_unload_info(struct seq_file *m, struct module *mod) |
1da177e4 LT |
1196 | { |
1197 | /* We don't know the usage count, or what modules are using. */ | |
6da0b565 | 1198 | seq_puts(m, " - -"); |
1da177e4 LT |
1199 | } |
1200 | ||
1201 | static inline void module_unload_free(struct module *mod) | |
1202 | { | |
1203 | } | |
1204 | ||
7ef5264d | 1205 | static int ref_module(struct module *a, struct module *b) |
1da177e4 | 1206 | { |
9bea7f23 | 1207 | return strong_try_module_get(b); |
1da177e4 LT |
1208 | } |
1209 | ||
9f85a4bb | 1210 | static inline int module_unload_init(struct module *mod) |
1da177e4 | 1211 | { |
9f85a4bb | 1212 | return 0; |
1da177e4 LT |
1213 | } |
1214 | #endif /* CONFIG_MODULE_UNLOAD */ | |
1215 | ||
53999bf3 KW |
1216 | static size_t module_flags_taint(struct module *mod, char *buf) |
1217 | { | |
1218 | size_t l = 0; | |
7fd8329b PM |
1219 | int i; |
1220 | ||
1221 | for (i = 0; i < TAINT_FLAGS_COUNT; i++) { | |
1222 | if (taint_flags[i].module && test_bit(i, &mod->taints)) | |
5eb7c0d0 | 1223 | buf[l++] = taint_flags[i].c_true; |
7fd8329b | 1224 | } |
53999bf3 | 1225 | |
53999bf3 KW |
1226 | return l; |
1227 | } | |
1228 | ||
1f71740a | 1229 | static ssize_t show_initstate(struct module_attribute *mattr, |
4befb026 | 1230 | struct module_kobject *mk, char *buffer) |
1f71740a KS |
1231 | { |
1232 | const char *state = "unknown"; | |
1233 | ||
4befb026 | 1234 | switch (mk->mod->state) { |
1f71740a KS |
1235 | case MODULE_STATE_LIVE: |
1236 | state = "live"; | |
1237 | break; | |
1238 | case MODULE_STATE_COMING: | |
1239 | state = "coming"; | |
1240 | break; | |
1241 | case MODULE_STATE_GOING: | |
1242 | state = "going"; | |
1243 | break; | |
0d21b0e3 RR |
1244 | default: |
1245 | BUG(); | |
1f71740a KS |
1246 | } |
1247 | return sprintf(buffer, "%s\n", state); | |
1248 | } | |
1249 | ||
cca3e707 KS |
1250 | static struct module_attribute modinfo_initstate = |
1251 | __ATTR(initstate, 0444, show_initstate, NULL); | |
1f71740a | 1252 | |
88bfa324 KS |
1253 | static ssize_t store_uevent(struct module_attribute *mattr, |
1254 | struct module_kobject *mk, | |
1255 | const char *buffer, size_t count) | |
1256 | { | |
df44b479 PR |
1257 | int rc; |
1258 | ||
1259 | rc = kobject_synth_uevent(&mk->kobj, buffer, count); | |
1260 | return rc ? rc : count; | |
88bfa324 KS |
1261 | } |
1262 | ||
cca3e707 KS |
1263 | struct module_attribute module_uevent = |
1264 | __ATTR(uevent, 0200, NULL, store_uevent); | |
1265 | ||
1266 | static ssize_t show_coresize(struct module_attribute *mattr, | |
1267 | struct module_kobject *mk, char *buffer) | |
1268 | { | |
7523e4dc | 1269 | return sprintf(buffer, "%u\n", mk->mod->core_layout.size); |
cca3e707 KS |
1270 | } |
1271 | ||
1272 | static struct module_attribute modinfo_coresize = | |
1273 | __ATTR(coresize, 0444, show_coresize, NULL); | |
1274 | ||
1275 | static ssize_t show_initsize(struct module_attribute *mattr, | |
1276 | struct module_kobject *mk, char *buffer) | |
1277 | { | |
7523e4dc | 1278 | return sprintf(buffer, "%u\n", mk->mod->init_layout.size); |
cca3e707 KS |
1279 | } |
1280 | ||
1281 | static struct module_attribute modinfo_initsize = | |
1282 | __ATTR(initsize, 0444, show_initsize, NULL); | |
1283 | ||
1284 | static ssize_t show_taint(struct module_attribute *mattr, | |
1285 | struct module_kobject *mk, char *buffer) | |
1286 | { | |
1287 | size_t l; | |
1288 | ||
1289 | l = module_flags_taint(mk->mod, buffer); | |
1290 | buffer[l++] = '\n'; | |
1291 | return l; | |
1292 | } | |
1293 | ||
1294 | static struct module_attribute modinfo_taint = | |
1295 | __ATTR(taint, 0444, show_taint, NULL); | |
88bfa324 | 1296 | |
03e88ae1 | 1297 | static struct module_attribute *modinfo_attrs[] = { |
cca3e707 | 1298 | &module_uevent, |
03e88ae1 GKH |
1299 | &modinfo_version, |
1300 | &modinfo_srcversion, | |
cca3e707 KS |
1301 | &modinfo_initstate, |
1302 | &modinfo_coresize, | |
1303 | &modinfo_initsize, | |
1304 | &modinfo_taint, | |
03e88ae1 | 1305 | #ifdef CONFIG_MODULE_UNLOAD |
cca3e707 | 1306 | &modinfo_refcnt, |
03e88ae1 GKH |
1307 | #endif |
1308 | NULL, | |
1309 | }; | |
1310 | ||
1da177e4 LT |
1311 | static const char vermagic[] = VERMAGIC_STRING; |
1312 | ||
c6e665c8 | 1313 | static int try_to_force_load(struct module *mod, const char *reason) |
826e4506 LT |
1314 | { |
1315 | #ifdef CONFIG_MODULE_FORCE_LOAD | |
25ddbb18 | 1316 | if (!test_taint(TAINT_FORCED_MODULE)) |
bddb12b3 | 1317 | pr_warn("%s: %s: kernel tainted.\n", mod->name, reason); |
373d4d09 | 1318 | add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE); |
826e4506 LT |
1319 | return 0; |
1320 | #else | |
1321 | return -ENOEXEC; | |
1322 | #endif | |
1323 | } | |
1324 | ||
1da177e4 | 1325 | #ifdef CONFIG_MODVERSIONS |
71810db2 AB |
1326 | |
1327 | static u32 resolve_rel_crc(const s32 *crc) | |
d4703aef | 1328 | { |
71810db2 | 1329 | return *(u32 *)((void *)crc + *crc); |
d4703aef RR |
1330 | } |
1331 | ||
49019426 | 1332 | static int check_version(const struct load_info *info, |
1da177e4 | 1333 | const char *symname, |
6da0b565 | 1334 | struct module *mod, |
71810db2 | 1335 | const s32 *crc) |
1da177e4 | 1336 | { |
49019426 KC |
1337 | Elf_Shdr *sechdrs = info->sechdrs; |
1338 | unsigned int versindex = info->index.vers; | |
1da177e4 LT |
1339 | unsigned int i, num_versions; |
1340 | struct modversion_info *versions; | |
1341 | ||
1342 | /* Exporting module didn't supply crcs? OK, we're already tainted. */ | |
1343 | if (!crc) | |
1344 | return 1; | |
1345 | ||
a5dd6970 RR |
1346 | /* No versions at all? modprobe --force does this. */ |
1347 | if (versindex == 0) | |
1348 | return try_to_force_load(mod, symname) == 0; | |
1349 | ||
1da177e4 LT |
1350 | versions = (void *) sechdrs[versindex].sh_addr; |
1351 | num_versions = sechdrs[versindex].sh_size | |
1352 | / sizeof(struct modversion_info); | |
1353 | ||
1354 | for (i = 0; i < num_versions; i++) { | |
71810db2 AB |
1355 | u32 crcval; |
1356 | ||
1da177e4 LT |
1357 | if (strcmp(versions[i].name, symname) != 0) |
1358 | continue; | |
1359 | ||
71810db2 AB |
1360 | if (IS_ENABLED(CONFIG_MODULE_REL_CRCS)) |
1361 | crcval = resolve_rel_crc(crc); | |
1362 | else | |
1363 | crcval = *crc; | |
1364 | if (versions[i].crc == crcval) | |
1da177e4 | 1365 | return 1; |
71810db2 AB |
1366 | pr_debug("Found checksum %X vs module %lX\n", |
1367 | crcval, versions[i].crc); | |
826e4506 | 1368 | goto bad_version; |
1da177e4 | 1369 | } |
826e4506 | 1370 | |
faaae2a5 | 1371 | /* Broken toolchain. Warn once, then let it go.. */ |
3e2e857f | 1372 | pr_warn_once("%s: no symbol version for %s\n", info->name, symname); |
faaae2a5 | 1373 | return 1; |
826e4506 LT |
1374 | |
1375 | bad_version: | |
6da0b565 | 1376 | pr_warn("%s: disagrees about version of symbol %s\n", |
3e2e857f | 1377 | info->name, symname); |
826e4506 | 1378 | return 0; |
1da177e4 LT |
1379 | } |
1380 | ||
49019426 | 1381 | static inline int check_modstruct_version(const struct load_info *info, |
1da177e4 LT |
1382 | struct module *mod) |
1383 | { | |
71810db2 | 1384 | const s32 *crc; |
1da177e4 | 1385 | |
926a59b1 PZ |
1386 | /* |
1387 | * Since this should be found in kernel (which can't be removed), no | |
1388 | * locking is necessary -- use preempt_disable() to placate lockdep. | |
1389 | */ | |
1390 | preempt_disable(); | |
ef1dac60 | 1391 | if (!find_symbol("module_layout", NULL, &crc, NULL, true, false)) { |
926a59b1 | 1392 | preempt_enable(); |
1da177e4 | 1393 | BUG(); |
926a59b1 PZ |
1394 | } |
1395 | preempt_enable(); | |
996302c5 | 1396 | return check_version(info, "module_layout", mod, crc); |
1da177e4 LT |
1397 | } |
1398 | ||
91e37a79 RR |
1399 | /* First part is kernel version, which we ignore if module has crcs. */ |
1400 | static inline int same_magic(const char *amagic, const char *bmagic, | |
1401 | bool has_crcs) | |
1da177e4 | 1402 | { |
91e37a79 RR |
1403 | if (has_crcs) { |
1404 | amagic += strcspn(amagic, " "); | |
1405 | bmagic += strcspn(bmagic, " "); | |
1406 | } | |
1da177e4 LT |
1407 | return strcmp(amagic, bmagic) == 0; |
1408 | } | |
1409 | #else | |
49019426 | 1410 | static inline int check_version(const struct load_info *info, |
1da177e4 | 1411 | const char *symname, |
6da0b565 | 1412 | struct module *mod, |
71810db2 | 1413 | const s32 *crc) |
1da177e4 LT |
1414 | { |
1415 | return 1; | |
1416 | } | |
1417 | ||
49019426 | 1418 | static inline int check_modstruct_version(const struct load_info *info, |
1da177e4 LT |
1419 | struct module *mod) |
1420 | { | |
1421 | return 1; | |
1422 | } | |
1423 | ||
91e37a79 RR |
1424 | static inline int same_magic(const char *amagic, const char *bmagic, |
1425 | bool has_crcs) | |
1da177e4 LT |
1426 | { |
1427 | return strcmp(amagic, bmagic) == 0; | |
1428 | } | |
1429 | #endif /* CONFIG_MODVERSIONS */ | |
1430 | ||
8651ec01 MM |
1431 | static char *get_modinfo(const struct load_info *info, const char *tag); |
1432 | static char *get_next_modinfo(const struct load_info *info, const char *tag, | |
1433 | char *prev); | |
1434 | ||
1435 | static int verify_namespace_is_imported(const struct load_info *info, | |
1436 | const struct kernel_symbol *sym, | |
1437 | struct module *mod) | |
1438 | { | |
1439 | const char *namespace; | |
1440 | char *imported_namespace; | |
1441 | ||
1442 | namespace = kernel_symbol_namespace(sym); | |
c3a6cf19 | 1443 | if (namespace && namespace[0]) { |
8651ec01 MM |
1444 | imported_namespace = get_modinfo(info, "import_ns"); |
1445 | while (imported_namespace) { | |
1446 | if (strcmp(namespace, imported_namespace) == 0) | |
1447 | return 0; | |
1448 | imported_namespace = get_next_modinfo( | |
1449 | info, "import_ns", imported_namespace); | |
1450 | } | |
3d52ec5e MM |
1451 | #ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS |
1452 | pr_warn( | |
1453 | #else | |
1454 | pr_err( | |
1455 | #endif | |
1456 | "%s: module uses symbol (%s) from namespace %s, but does not import it.\n", | |
1457 | mod->name, kernel_symbol_name(sym), namespace); | |
1458 | #ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS | |
8651ec01 | 1459 | return -EINVAL; |
3d52ec5e | 1460 | #endif |
8651ec01 MM |
1461 | } |
1462 | return 0; | |
1463 | } | |
1464 | ||
262e6ae7 CH |
1465 | static bool inherit_taint(struct module *mod, struct module *owner) |
1466 | { | |
1467 | if (!owner || !test_bit(TAINT_PROPRIETARY_MODULE, &owner->taints)) | |
1468 | return true; | |
1469 | ||
1470 | if (mod->using_gplonly_symbols) { | |
1471 | pr_err("%s: module using GPL-only symbols uses symbols from proprietary module %s.\n", | |
1472 | mod->name, owner->name); | |
1473 | return false; | |
1474 | } | |
1475 | ||
1476 | if (!test_bit(TAINT_PROPRIETARY_MODULE, &mod->taints)) { | |
1477 | pr_warn("%s: module uses symbols from proprietary module %s, inheriting taint.\n", | |
1478 | mod->name, owner->name); | |
1479 | set_bit(TAINT_PROPRIETARY_MODULE, &mod->taints); | |
1480 | } | |
1481 | return true; | |
1482 | } | |
8651ec01 | 1483 | |
75676500 | 1484 | /* Resolve a symbol for this module. I.e. if we find one, record usage. */ |
49668688 RR |
1485 | static const struct kernel_symbol *resolve_symbol(struct module *mod, |
1486 | const struct load_info *info, | |
414fd31b | 1487 | const char *name, |
9bea7f23 | 1488 | char ownername[]) |
1da177e4 LT |
1489 | { |
1490 | struct module *owner; | |
414fd31b | 1491 | const struct kernel_symbol *sym; |
71810db2 | 1492 | const s32 *crc; |
ef1dac60 | 1493 | enum mod_license license; |
9bea7f23 | 1494 | int err; |
1da177e4 | 1495 | |
d64810f5 PZ |
1496 | /* |
1497 | * The module_mutex should not be a heavily contended lock; | |
1498 | * if we get the occasional sleep here, we'll go an extra iteration | |
1499 | * in the wait_event_interruptible(), which is harmless. | |
1500 | */ | |
1501 | sched_annotate_sleep(); | |
75676500 | 1502 | mutex_lock(&module_mutex); |
ef1dac60 | 1503 | sym = find_symbol(name, &owner, &crc, &license, |
25ddbb18 | 1504 | !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true); |
9bea7f23 RR |
1505 | if (!sym) |
1506 | goto unlock; | |
1507 | ||
262e6ae7 CH |
1508 | if (license == GPL_ONLY) |
1509 | mod->using_gplonly_symbols = true; | |
1510 | ||
1511 | if (!inherit_taint(mod, owner)) { | |
1512 | sym = NULL; | |
1513 | goto getname; | |
1514 | } | |
1515 | ||
49019426 | 1516 | if (!check_version(info, name, mod, crc)) { |
9bea7f23 RR |
1517 | sym = ERR_PTR(-EINVAL); |
1518 | goto getname; | |
1da177e4 | 1519 | } |
9bea7f23 | 1520 | |
8651ec01 MM |
1521 | err = verify_namespace_is_imported(info, sym, mod); |
1522 | if (err) { | |
1523 | sym = ERR_PTR(err); | |
1524 | goto getname; | |
1525 | } | |
1526 | ||
9bea7f23 RR |
1527 | err = ref_module(mod, owner); |
1528 | if (err) { | |
1529 | sym = ERR_PTR(err); | |
1530 | goto getname; | |
1531 | } | |
1532 | ||
1533 | getname: | |
1534 | /* We must make copy under the lock if we failed to get ref. */ | |
1535 | strncpy(ownername, module_name(owner), MODULE_NAME_LEN); | |
1536 | unlock: | |
75676500 | 1537 | mutex_unlock(&module_mutex); |
218ce735 | 1538 | return sym; |
1da177e4 LT |
1539 | } |
1540 | ||
49668688 RR |
1541 | static const struct kernel_symbol * |
1542 | resolve_symbol_wait(struct module *mod, | |
1543 | const struct load_info *info, | |
1544 | const char *name) | |
9bea7f23 RR |
1545 | { |
1546 | const struct kernel_symbol *ksym; | |
49668688 | 1547 | char owner[MODULE_NAME_LEN]; |
9bea7f23 RR |
1548 | |
1549 | if (wait_event_interruptible_timeout(module_wq, | |
49668688 RR |
1550 | !IS_ERR(ksym = resolve_symbol(mod, info, name, owner)) |
1551 | || PTR_ERR(ksym) != -EBUSY, | |
9bea7f23 | 1552 | 30 * HZ) <= 0) { |
bddb12b3 AM |
1553 | pr_warn("%s: gave up waiting for init of module %s.\n", |
1554 | mod->name, owner); | |
9bea7f23 RR |
1555 | } |
1556 | return ksym; | |
1557 | } | |
1558 | ||
1da177e4 LT |
1559 | /* |
1560 | * /sys/module/foo/sections stuff | |
1561 | * J. Corbet <corbet@lwn.net> | |
1562 | */ | |
8f6d0378 | 1563 | #ifdef CONFIG_SYSFS |
10b465aa | 1564 | |
8f6d0378 | 1565 | #ifdef CONFIG_KALLSYMS |
10b465aa BH |
1566 | static inline bool sect_empty(const Elf_Shdr *sect) |
1567 | { | |
1568 | return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0; | |
1569 | } | |
1570 | ||
6da0b565 | 1571 | struct module_sect_attr { |
ed66f991 | 1572 | struct bin_attribute battr; |
a58730c4 RR |
1573 | unsigned long address; |
1574 | }; | |
1575 | ||
6da0b565 | 1576 | struct module_sect_attrs { |
a58730c4 RR |
1577 | struct attribute_group grp; |
1578 | unsigned int nsections; | |
0f742266 | 1579 | struct module_sect_attr attrs[]; |
a58730c4 RR |
1580 | }; |
1581 | ||
11990a5b | 1582 | #define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4)) |
ed66f991 KC |
1583 | static ssize_t module_sect_read(struct file *file, struct kobject *kobj, |
1584 | struct bin_attribute *battr, | |
1585 | char *buf, loff_t pos, size_t count) | |
1da177e4 LT |
1586 | { |
1587 | struct module_sect_attr *sattr = | |
ed66f991 | 1588 | container_of(battr, struct module_sect_attr, battr); |
11990a5b KC |
1589 | char bounce[MODULE_SECT_READ_SIZE + 1]; |
1590 | size_t wrote; | |
ed66f991 KC |
1591 | |
1592 | if (pos != 0) | |
1593 | return -EINVAL; | |
1594 | ||
11990a5b KC |
1595 | /* |
1596 | * Since we're a binary read handler, we must account for the | |
1597 | * trailing NUL byte that sprintf will write: if "buf" is | |
1598 | * too small to hold the NUL, or the NUL is exactly the last | |
1599 | * byte, the read will look like it got truncated by one byte. | |
1600 | * Since there is no way to ask sprintf nicely to not write | |
1601 | * the NUL, we have to use a bounce buffer. | |
1602 | */ | |
1603 | wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n", | |
1604 | kallsyms_show_value(file->f_cred) | |
1605 | ? (void *)sattr->address : NULL); | |
1606 | count = min(count, wrote); | |
1607 | memcpy(buf, bounce, count); | |
1608 | ||
1609 | return count; | |
1da177e4 LT |
1610 | } |
1611 | ||
04b1db9f IN |
1612 | static void free_sect_attrs(struct module_sect_attrs *sect_attrs) |
1613 | { | |
a58730c4 | 1614 | unsigned int section; |
04b1db9f IN |
1615 | |
1616 | for (section = 0; section < sect_attrs->nsections; section++) | |
ed66f991 | 1617 | kfree(sect_attrs->attrs[section].battr.attr.name); |
04b1db9f IN |
1618 | kfree(sect_attrs); |
1619 | } | |
1620 | ||
8f6d0378 | 1621 | static void add_sect_attrs(struct module *mod, const struct load_info *info) |
1da177e4 LT |
1622 | { |
1623 | unsigned int nloaded = 0, i, size[2]; | |
1624 | struct module_sect_attrs *sect_attrs; | |
1625 | struct module_sect_attr *sattr; | |
ed66f991 | 1626 | struct bin_attribute **gattr; |
22a8bdeb | 1627 | |
1da177e4 | 1628 | /* Count loaded sections and allocate structures */ |
8f6d0378 RR |
1629 | for (i = 0; i < info->hdr->e_shnum; i++) |
1630 | if (!sect_empty(&info->sechdrs[i])) | |
1da177e4 | 1631 | nloaded++; |
8d1b73dd | 1632 | size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded), |
ed66f991 KC |
1633 | sizeof(sect_attrs->grp.bin_attrs[0])); |
1634 | size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]); | |
04b1db9f IN |
1635 | sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); |
1636 | if (sect_attrs == NULL) | |
1da177e4 LT |
1637 | return; |
1638 | ||
1639 | /* Setup section attributes. */ | |
1640 | sect_attrs->grp.name = "sections"; | |
ed66f991 | 1641 | sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0]; |
1da177e4 | 1642 | |
04b1db9f | 1643 | sect_attrs->nsections = 0; |
1da177e4 | 1644 | sattr = §_attrs->attrs[0]; |
ed66f991 | 1645 | gattr = §_attrs->grp.bin_attrs[0]; |
8f6d0378 RR |
1646 | for (i = 0; i < info->hdr->e_shnum; i++) { |
1647 | Elf_Shdr *sec = &info->sechdrs[i]; | |
1648 | if (sect_empty(sec)) | |
35dead42 | 1649 | continue; |
ed66f991 | 1650 | sysfs_bin_attr_init(&sattr->battr); |
8f6d0378 | 1651 | sattr->address = sec->sh_addr; |
ed66f991 KC |
1652 | sattr->battr.attr.name = |
1653 | kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL); | |
1654 | if (sattr->battr.attr.name == NULL) | |
04b1db9f IN |
1655 | goto out; |
1656 | sect_attrs->nsections++; | |
ed66f991 | 1657 | sattr->battr.read = module_sect_read; |
11990a5b | 1658 | sattr->battr.size = MODULE_SECT_READ_SIZE; |
ed66f991 KC |
1659 | sattr->battr.attr.mode = 0400; |
1660 | *(gattr++) = &(sattr++)->battr; | |
1da177e4 LT |
1661 | } |
1662 | *gattr = NULL; | |
1663 | ||
1664 | if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) | |
1665 | goto out; | |
1666 | ||
1667 | mod->sect_attrs = sect_attrs; | |
1668 | return; | |
1669 | out: | |
04b1db9f | 1670 | free_sect_attrs(sect_attrs); |
1da177e4 LT |
1671 | } |
1672 | ||
1673 | static void remove_sect_attrs(struct module *mod) | |
1674 | { | |
1675 | if (mod->sect_attrs) { | |
1676 | sysfs_remove_group(&mod->mkobj.kobj, | |
1677 | &mod->sect_attrs->grp); | |
24b9f0d2 SS |
1678 | /* |
1679 | * We are positive that no one is using any sect attrs | |
1680 | * at this point. Deallocate immediately. | |
1681 | */ | |
04b1db9f | 1682 | free_sect_attrs(mod->sect_attrs); |
1da177e4 LT |
1683 | mod->sect_attrs = NULL; |
1684 | } | |
1685 | } | |
1686 | ||
6d760133 RM |
1687 | /* |
1688 | * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. | |
1689 | */ | |
1690 | ||
1691 | struct module_notes_attrs { | |
1692 | struct kobject *dir; | |
1693 | unsigned int notes; | |
0f742266 | 1694 | struct bin_attribute attrs[]; |
6d760133 RM |
1695 | }; |
1696 | ||
2c3c8bea | 1697 | static ssize_t module_notes_read(struct file *filp, struct kobject *kobj, |
6d760133 RM |
1698 | struct bin_attribute *bin_attr, |
1699 | char *buf, loff_t pos, size_t count) | |
1700 | { | |
1701 | /* | |
1702 | * The caller checked the pos and count against our size. | |
1703 | */ | |
1704 | memcpy(buf, bin_attr->private + pos, count); | |
1705 | return count; | |
1706 | } | |
1707 | ||
1708 | static void free_notes_attrs(struct module_notes_attrs *notes_attrs, | |
1709 | unsigned int i) | |
1710 | { | |
1711 | if (notes_attrs->dir) { | |
1712 | while (i-- > 0) | |
1713 | sysfs_remove_bin_file(notes_attrs->dir, | |
1714 | ¬es_attrs->attrs[i]); | |
e9432093 | 1715 | kobject_put(notes_attrs->dir); |
6d760133 RM |
1716 | } |
1717 | kfree(notes_attrs); | |
1718 | } | |
1719 | ||
8f6d0378 | 1720 | static void add_notes_attrs(struct module *mod, const struct load_info *info) |
6d760133 RM |
1721 | { |
1722 | unsigned int notes, loaded, i; | |
1723 | struct module_notes_attrs *notes_attrs; | |
1724 | struct bin_attribute *nattr; | |
1725 | ||
ea6bff36 IM |
1726 | /* failed to create section attributes, so can't create notes */ |
1727 | if (!mod->sect_attrs) | |
1728 | return; | |
1729 | ||
6d760133 RM |
1730 | /* Count notes sections and allocate structures. */ |
1731 | notes = 0; | |
8f6d0378 RR |
1732 | for (i = 0; i < info->hdr->e_shnum; i++) |
1733 | if (!sect_empty(&info->sechdrs[i]) && | |
1734 | (info->sechdrs[i].sh_type == SHT_NOTE)) | |
6d760133 RM |
1735 | ++notes; |
1736 | ||
1737 | if (notes == 0) | |
1738 | return; | |
1739 | ||
acafe7e3 | 1740 | notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes), |
6d760133 RM |
1741 | GFP_KERNEL); |
1742 | if (notes_attrs == NULL) | |
1743 | return; | |
1744 | ||
1745 | notes_attrs->notes = notes; | |
1746 | nattr = ¬es_attrs->attrs[0]; | |
8f6d0378 RR |
1747 | for (loaded = i = 0; i < info->hdr->e_shnum; ++i) { |
1748 | if (sect_empty(&info->sechdrs[i])) | |
6d760133 | 1749 | continue; |
8f6d0378 | 1750 | if (info->sechdrs[i].sh_type == SHT_NOTE) { |
361795b1 | 1751 | sysfs_bin_attr_init(nattr); |
ed66f991 | 1752 | nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name; |
6d760133 | 1753 | nattr->attr.mode = S_IRUGO; |
8f6d0378 RR |
1754 | nattr->size = info->sechdrs[i].sh_size; |
1755 | nattr->private = (void *) info->sechdrs[i].sh_addr; | |
6d760133 RM |
1756 | nattr->read = module_notes_read; |
1757 | ++nattr; | |
1758 | } | |
1759 | ++loaded; | |
1760 | } | |
1761 | ||
4ff6abff | 1762 | notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); |
6d760133 RM |
1763 | if (!notes_attrs->dir) |
1764 | goto out; | |
1765 | ||
1766 | for (i = 0; i < notes; ++i) | |
1767 | if (sysfs_create_bin_file(notes_attrs->dir, | |
1768 | ¬es_attrs->attrs[i])) | |
1769 | goto out; | |
1770 | ||
1771 | mod->notes_attrs = notes_attrs; | |
1772 | return; | |
1773 | ||
1774 | out: | |
1775 | free_notes_attrs(notes_attrs, i); | |
1776 | } | |
1777 | ||
1778 | static void remove_notes_attrs(struct module *mod) | |
1779 | { | |
1780 | if (mod->notes_attrs) | |
1781 | free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); | |
1782 | } | |
1783 | ||
1da177e4 | 1784 | #else |
04b1db9f | 1785 | |
8f6d0378 RR |
1786 | static inline void add_sect_attrs(struct module *mod, |
1787 | const struct load_info *info) | |
1da177e4 LT |
1788 | { |
1789 | } | |
1790 | ||
1791 | static inline void remove_sect_attrs(struct module *mod) | |
1792 | { | |
1793 | } | |
6d760133 | 1794 | |
8f6d0378 RR |
1795 | static inline void add_notes_attrs(struct module *mod, |
1796 | const struct load_info *info) | |
6d760133 RM |
1797 | { |
1798 | } | |
1799 | ||
1800 | static inline void remove_notes_attrs(struct module *mod) | |
1801 | { | |
1802 | } | |
8f6d0378 | 1803 | #endif /* CONFIG_KALLSYMS */ |
1da177e4 | 1804 | |
1ba5c08b | 1805 | static void del_usage_links(struct module *mod) |
80a3d1bb RR |
1806 | { |
1807 | #ifdef CONFIG_MODULE_UNLOAD | |
1808 | struct module_use *use; | |
80a3d1bb | 1809 | |
75676500 | 1810 | mutex_lock(&module_mutex); |
1ba5c08b CL |
1811 | list_for_each_entry(use, &mod->target_list, target_list) |
1812 | sysfs_remove_link(use->target->holders_dir, mod->name); | |
75676500 | 1813 | mutex_unlock(&module_mutex); |
80a3d1bb RR |
1814 | #endif |
1815 | } | |
1816 | ||
1ba5c08b | 1817 | static int add_usage_links(struct module *mod) |
80a3d1bb | 1818 | { |
1ba5c08b | 1819 | int ret = 0; |
80a3d1bb RR |
1820 | #ifdef CONFIG_MODULE_UNLOAD |
1821 | struct module_use *use; | |
1822 | ||
75676500 | 1823 | mutex_lock(&module_mutex); |
1ba5c08b CL |
1824 | list_for_each_entry(use, &mod->target_list, target_list) { |
1825 | ret = sysfs_create_link(use->target->holders_dir, | |
1826 | &mod->mkobj.kobj, mod->name); | |
1827 | if (ret) | |
1828 | break; | |
1829 | } | |
75676500 | 1830 | mutex_unlock(&module_mutex); |
1ba5c08b CL |
1831 | if (ret) |
1832 | del_usage_links(mod); | |
80a3d1bb | 1833 | #endif |
1ba5c08b | 1834 | return ret; |
80a3d1bb RR |
1835 | } |
1836 | ||
bc6f2a75 Y |
1837 | static void module_remove_modinfo_attrs(struct module *mod, int end); |
1838 | ||
6407ebb2 | 1839 | static int module_add_modinfo_attrs(struct module *mod) |
c988d2b2 MD |
1840 | { |
1841 | struct module_attribute *attr; | |
03e88ae1 | 1842 | struct module_attribute *temp_attr; |
c988d2b2 MD |
1843 | int error = 0; |
1844 | int i; | |
1845 | ||
03e88ae1 GKH |
1846 | mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * |
1847 | (ARRAY_SIZE(modinfo_attrs) + 1)), | |
1848 | GFP_KERNEL); | |
1849 | if (!mod->modinfo_attrs) | |
1850 | return -ENOMEM; | |
1851 | ||
1852 | temp_attr = mod->modinfo_attrs; | |
bc6f2a75 | 1853 | for (i = 0; (attr = modinfo_attrs[i]); i++) { |
c75b590d | 1854 | if (!attr->test || attr->test(mod)) { |
03e88ae1 | 1855 | memcpy(temp_attr, attr, sizeof(*temp_attr)); |
361795b1 | 1856 | sysfs_attr_init(&temp_attr->attr); |
6da0b565 IA |
1857 | error = sysfs_create_file(&mod->mkobj.kobj, |
1858 | &temp_attr->attr); | |
bc6f2a75 Y |
1859 | if (error) |
1860 | goto error_out; | |
03e88ae1 GKH |
1861 | ++temp_attr; |
1862 | } | |
c988d2b2 | 1863 | } |
bc6f2a75 Y |
1864 | |
1865 | return 0; | |
1866 | ||
1867 | error_out: | |
1868 | if (i > 0) | |
1869 | module_remove_modinfo_attrs(mod, --i); | |
f6d061d6 Y |
1870 | else |
1871 | kfree(mod->modinfo_attrs); | |
c988d2b2 MD |
1872 | return error; |
1873 | } | |
1874 | ||
bc6f2a75 | 1875 | static void module_remove_modinfo_attrs(struct module *mod, int end) |
c988d2b2 MD |
1876 | { |
1877 | struct module_attribute *attr; | |
1878 | int i; | |
1879 | ||
03e88ae1 | 1880 | for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { |
bc6f2a75 Y |
1881 | if (end >= 0 && i > end) |
1882 | break; | |
03e88ae1 GKH |
1883 | /* pick a field to test for end of list */ |
1884 | if (!attr->attr.name) | |
1885 | break; | |
6da0b565 | 1886 | sysfs_remove_file(&mod->mkobj.kobj, &attr->attr); |
03e88ae1 GKH |
1887 | if (attr->free) |
1888 | attr->free(mod); | |
c988d2b2 | 1889 | } |
03e88ae1 | 1890 | kfree(mod->modinfo_attrs); |
c988d2b2 | 1891 | } |
1da177e4 | 1892 | |
942e4431 LZ |
1893 | static void mod_kobject_put(struct module *mod) |
1894 | { | |
1895 | DECLARE_COMPLETION_ONSTACK(c); | |
1896 | mod->mkobj.kobj_completion = &c; | |
1897 | kobject_put(&mod->mkobj.kobj); | |
1898 | wait_for_completion(&c); | |
1899 | } | |
1900 | ||
6407ebb2 | 1901 | static int mod_sysfs_init(struct module *mod) |
1da177e4 LT |
1902 | { |
1903 | int err; | |
6494a93d | 1904 | struct kobject *kobj; |
1da177e4 | 1905 | |
823bccfc | 1906 | if (!module_sysfs_initialized) { |
bddb12b3 | 1907 | pr_err("%s: module sysfs not initialized\n", mod->name); |
1cc5f714 ES |
1908 | err = -EINVAL; |
1909 | goto out; | |
1910 | } | |
6494a93d GKH |
1911 | |
1912 | kobj = kset_find_obj(module_kset, mod->name); | |
1913 | if (kobj) { | |
bddb12b3 | 1914 | pr_err("%s: module is already loaded\n", mod->name); |
6494a93d GKH |
1915 | kobject_put(kobj); |
1916 | err = -EINVAL; | |
1917 | goto out; | |
1918 | } | |
1919 | ||
1da177e4 | 1920 | mod->mkobj.mod = mod; |
e17e0f51 | 1921 | |
ac3c8141 GKH |
1922 | memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); |
1923 | mod->mkobj.kobj.kset = module_kset; | |
1924 | err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, | |
1925 | "%s", mod->name); | |
1926 | if (err) | |
942e4431 | 1927 | mod_kobject_put(mod); |
270a6c4c KS |
1928 | |
1929 | out: | |
1930 | return err; | |
1931 | } | |
1932 | ||
6407ebb2 | 1933 | static int mod_sysfs_setup(struct module *mod, |
8f6d0378 | 1934 | const struct load_info *info, |
270a6c4c KS |
1935 | struct kernel_param *kparam, |
1936 | unsigned int num_params) | |
1937 | { | |
1938 | int err; | |
1939 | ||
80a3d1bb RR |
1940 | err = mod_sysfs_init(mod); |
1941 | if (err) | |
1942 | goto out; | |
1943 | ||
4ff6abff | 1944 | mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); |
240936e1 AM |
1945 | if (!mod->holders_dir) { |
1946 | err = -ENOMEM; | |
270a6c4c | 1947 | goto out_unreg; |
240936e1 | 1948 | } |
270a6c4c | 1949 | |
1da177e4 LT |
1950 | err = module_param_sysfs_setup(mod, kparam, num_params); |
1951 | if (err) | |
270a6c4c | 1952 | goto out_unreg_holders; |
1da177e4 | 1953 | |
c988d2b2 MD |
1954 | err = module_add_modinfo_attrs(mod); |
1955 | if (err) | |
e17e0f51 | 1956 | goto out_unreg_param; |
c988d2b2 | 1957 | |
1ba5c08b CL |
1958 | err = add_usage_links(mod); |
1959 | if (err) | |
1960 | goto out_unreg_modinfo_attrs; | |
1961 | ||
8f6d0378 RR |
1962 | add_sect_attrs(mod, info); |
1963 | add_notes_attrs(mod, info); | |
80a3d1bb | 1964 | |
1da177e4 LT |
1965 | return 0; |
1966 | ||
1ba5c08b | 1967 | out_unreg_modinfo_attrs: |
bc6f2a75 | 1968 | module_remove_modinfo_attrs(mod, -1); |
e17e0f51 KS |
1969 | out_unreg_param: |
1970 | module_param_sysfs_remove(mod); | |
270a6c4c | 1971 | out_unreg_holders: |
78a2d906 | 1972 | kobject_put(mod->holders_dir); |
270a6c4c | 1973 | out_unreg: |
942e4431 | 1974 | mod_kobject_put(mod); |
80a3d1bb | 1975 | out: |
1da177e4 LT |
1976 | return err; |
1977 | } | |
34e4e2fe DL |
1978 | |
1979 | static void mod_sysfs_fini(struct module *mod) | |
1980 | { | |
8f6d0378 RR |
1981 | remove_notes_attrs(mod); |
1982 | remove_sect_attrs(mod); | |
942e4431 | 1983 | mod_kobject_put(mod); |
34e4e2fe DL |
1984 | } |
1985 | ||
cf2fde7b RR |
1986 | static void init_param_lock(struct module *mod) |
1987 | { | |
1988 | mutex_init(&mod->param_lock); | |
1989 | } | |
8f6d0378 | 1990 | #else /* !CONFIG_SYSFS */ |
34e4e2fe | 1991 | |
8f6d0378 RR |
1992 | static int mod_sysfs_setup(struct module *mod, |
1993 | const struct load_info *info, | |
6407ebb2 RR |
1994 | struct kernel_param *kparam, |
1995 | unsigned int num_params) | |
1996 | { | |
1997 | return 0; | |
1998 | } | |
1999 | ||
34e4e2fe DL |
2000 | static void mod_sysfs_fini(struct module *mod) |
2001 | { | |
2002 | } | |
2003 | ||
bc6f2a75 | 2004 | static void module_remove_modinfo_attrs(struct module *mod, int end) |
36b0360d RR |
2005 | { |
2006 | } | |
2007 | ||
80a3d1bb RR |
2008 | static void del_usage_links(struct module *mod) |
2009 | { | |
2010 | } | |
2011 | ||
cf2fde7b RR |
2012 | static void init_param_lock(struct module *mod) |
2013 | { | |
2014 | } | |
34e4e2fe | 2015 | #endif /* CONFIG_SYSFS */ |
1da177e4 | 2016 | |
36b0360d | 2017 | static void mod_sysfs_teardown(struct module *mod) |
1da177e4 | 2018 | { |
80a3d1bb | 2019 | del_usage_links(mod); |
bc6f2a75 | 2020 | module_remove_modinfo_attrs(mod, -1); |
1da177e4 | 2021 | module_param_sysfs_remove(mod); |
78a2d906 GKH |
2022 | kobject_put(mod->mkobj.drivers_dir); |
2023 | kobject_put(mod->holders_dir); | |
34e4e2fe | 2024 | mod_sysfs_fini(mod); |
1da177e4 LT |
2025 | } |
2026 | ||
84e1c6bb MC |
2027 | /* |
2028 | * LKM RO/NX protection: protect module's text/ro-data | |
2029 | * from modification and any data from execution. | |
85c898db RR |
2030 | * |
2031 | * General layout of module is: | |
444d13ff JY |
2032 | * [text] [read-only-data] [ro-after-init] [writable data] |
2033 | * text_size -----^ ^ ^ ^ | |
2034 | * ro_size ------------------------| | | | |
2035 | * ro_after_init_size -----------------------------| | | |
2036 | * size -----------------------------------------------------------| | |
85c898db RR |
2037 | * |
2038 | * These values are always page-aligned (as is base) | |
84e1c6bb | 2039 | */ |
db991af0 JY |
2040 | |
2041 | /* | |
2042 | * Since some arches are moving towards PAGE_KERNEL module allocations instead | |
2043 | * of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() outside of the | |
2044 | * CONFIG_STRICT_MODULE_RWX block below because they are needed regardless of | |
2045 | * whether we are strict. | |
2046 | */ | |
2047 | #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX | |
85c898db RR |
2048 | static void frob_text(const struct module_layout *layout, |
2049 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 2050 | { |
85c898db RR |
2051 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
2052 | BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1)); | |
2053 | set_memory((unsigned long)layout->base, | |
2054 | layout->text_size >> PAGE_SHIFT); | |
84e1c6bb | 2055 | } |
84e1c6bb | 2056 | |
db991af0 JY |
2057 | static void module_enable_x(const struct module *mod) |
2058 | { | |
2059 | frob_text(&mod->core_layout, set_memory_x); | |
2060 | frob_text(&mod->init_layout, set_memory_x); | |
2061 | } | |
2062 | #else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */ | |
2063 | static void module_enable_x(const struct module *mod) { } | |
2064 | #endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */ | |
2065 | ||
93651f80 | 2066 | #ifdef CONFIG_STRICT_MODULE_RWX |
85c898db RR |
2067 | static void frob_rodata(const struct module_layout *layout, |
2068 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 2069 | { |
85c898db RR |
2070 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
2071 | BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1)); | |
2072 | BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1)); | |
2073 | set_memory((unsigned long)layout->base + layout->text_size, | |
2074 | (layout->ro_size - layout->text_size) >> PAGE_SHIFT); | |
84e1c6bb MC |
2075 | } |
2076 | ||
444d13ff JY |
2077 | static void frob_ro_after_init(const struct module_layout *layout, |
2078 | int (*set_memory)(unsigned long start, int num_pages)) | |
2079 | { | |
2080 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); | |
2081 | BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1)); | |
2082 | BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1)); | |
2083 | set_memory((unsigned long)layout->base + layout->ro_size, | |
2084 | (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT); | |
2085 | } | |
2086 | ||
85c898db RR |
2087 | static void frob_writable_data(const struct module_layout *layout, |
2088 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 2089 | { |
85c898db | 2090 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
444d13ff | 2091 | BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1)); |
85c898db | 2092 | BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1)); |
444d13ff JY |
2093 | set_memory((unsigned long)layout->base + layout->ro_after_init_size, |
2094 | (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT); | |
84e1c6bb | 2095 | } |
84e1c6bb | 2096 | |
e6eff437 | 2097 | static void module_enable_ro(const struct module *mod, bool after_init) |
01526ed0 | 2098 | { |
39290b38 AT |
2099 | if (!rodata_enabled) |
2100 | return; | |
2101 | ||
1a7b7d92 RE |
2102 | set_vm_flush_reset_perms(mod->core_layout.base); |
2103 | set_vm_flush_reset_perms(mod->init_layout.base); | |
85c898db | 2104 | frob_text(&mod->core_layout, set_memory_ro); |
f2c65fb3 | 2105 | |
85c898db RR |
2106 | frob_rodata(&mod->core_layout, set_memory_ro); |
2107 | frob_text(&mod->init_layout, set_memory_ro); | |
2108 | frob_rodata(&mod->init_layout, set_memory_ro); | |
444d13ff JY |
2109 | |
2110 | if (after_init) | |
2111 | frob_ro_after_init(&mod->core_layout, set_memory_ro); | |
84e1c6bb MC |
2112 | } |
2113 | ||
85c898db | 2114 | static void module_enable_nx(const struct module *mod) |
01526ed0 | 2115 | { |
85c898db | 2116 | frob_rodata(&mod->core_layout, set_memory_nx); |
444d13ff | 2117 | frob_ro_after_init(&mod->core_layout, set_memory_nx); |
85c898db RR |
2118 | frob_writable_data(&mod->core_layout, set_memory_nx); |
2119 | frob_rodata(&mod->init_layout, set_memory_nx); | |
2120 | frob_writable_data(&mod->init_layout, set_memory_nx); | |
01526ed0 JG |
2121 | } |
2122 | ||
5c3a7db0 PZ |
2123 | static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, |
2124 | char *secstrings, struct module *mod) | |
2125 | { | |
2126 | const unsigned long shf_wx = SHF_WRITE|SHF_EXECINSTR; | |
2127 | int i; | |
2128 | ||
2129 | for (i = 0; i < hdr->e_shnum; i++) { | |
14721add QW |
2130 | if ((sechdrs[i].sh_flags & shf_wx) == shf_wx) { |
2131 | pr_err("%s: section %s (index %d) has invalid WRITE|EXEC flags\n", | |
2132 | mod->name, secstrings + sechdrs[i].sh_name, i); | |
5c3a7db0 | 2133 | return -ENOEXEC; |
14721add | 2134 | } |
5c3a7db0 PZ |
2135 | } |
2136 | ||
2137 | return 0; | |
2138 | } | |
2139 | ||
93651f80 | 2140 | #else /* !CONFIG_STRICT_MODULE_RWX */ |
85c898db | 2141 | static void module_enable_nx(const struct module *mod) { } |
e6eff437 | 2142 | static void module_enable_ro(const struct module *mod, bool after_init) {} |
5c3a7db0 PZ |
2143 | static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, |
2144 | char *secstrings, struct module *mod) | |
2eef1399 | 2145 | { |
5c3a7db0 | 2146 | return 0; |
2eef1399 | 2147 | } |
93651f80 | 2148 | #endif /* CONFIG_STRICT_MODULE_RWX */ |
84e1c6bb | 2149 | |
1ce15ef4 JY |
2150 | #ifdef CONFIG_LIVEPATCH |
2151 | /* | |
2152 | * Persist Elf information about a module. Copy the Elf header, | |
2153 | * section header table, section string table, and symtab section | |
2154 | * index from info to mod->klp_info. | |
2155 | */ | |
2156 | static int copy_module_elf(struct module *mod, struct load_info *info) | |
2157 | { | |
2158 | unsigned int size, symndx; | |
2159 | int ret; | |
2160 | ||
2161 | size = sizeof(*mod->klp_info); | |
2162 | mod->klp_info = kmalloc(size, GFP_KERNEL); | |
2163 | if (mod->klp_info == NULL) | |
2164 | return -ENOMEM; | |
2165 | ||
2166 | /* Elf header */ | |
2167 | size = sizeof(mod->klp_info->hdr); | |
2168 | memcpy(&mod->klp_info->hdr, info->hdr, size); | |
2169 | ||
2170 | /* Elf section header table */ | |
2171 | size = sizeof(*info->sechdrs) * info->hdr->e_shnum; | |
9be936f4 | 2172 | mod->klp_info->sechdrs = kmemdup(info->sechdrs, size, GFP_KERNEL); |
1ce15ef4 JY |
2173 | if (mod->klp_info->sechdrs == NULL) { |
2174 | ret = -ENOMEM; | |
2175 | goto free_info; | |
2176 | } | |
1ce15ef4 JY |
2177 | |
2178 | /* Elf section name string table */ | |
2179 | size = info->sechdrs[info->hdr->e_shstrndx].sh_size; | |
9be936f4 | 2180 | mod->klp_info->secstrings = kmemdup(info->secstrings, size, GFP_KERNEL); |
1ce15ef4 JY |
2181 | if (mod->klp_info->secstrings == NULL) { |
2182 | ret = -ENOMEM; | |
2183 | goto free_sechdrs; | |
2184 | } | |
1ce15ef4 JY |
2185 | |
2186 | /* Elf symbol section index */ | |
2187 | symndx = info->index.sym; | |
2188 | mod->klp_info->symndx = symndx; | |
2189 | ||
2190 | /* | |
2191 | * For livepatch modules, core_kallsyms.symtab is a complete | |
2192 | * copy of the original symbol table. Adjust sh_addr to point | |
2193 | * to core_kallsyms.symtab since the copy of the symtab in module | |
2194 | * init memory is freed at the end of do_init_module(). | |
2195 | */ | |
2196 | mod->klp_info->sechdrs[symndx].sh_addr = \ | |
2197 | (unsigned long) mod->core_kallsyms.symtab; | |
2198 | ||
2199 | return 0; | |
2200 | ||
2201 | free_sechdrs: | |
2202 | kfree(mod->klp_info->sechdrs); | |
2203 | free_info: | |
2204 | kfree(mod->klp_info); | |
2205 | return ret; | |
2206 | } | |
2207 | ||
2208 | static void free_module_elf(struct module *mod) | |
2209 | { | |
2210 | kfree(mod->klp_info->sechdrs); | |
2211 | kfree(mod->klp_info->secstrings); | |
2212 | kfree(mod->klp_info); | |
2213 | } | |
2214 | #else /* !CONFIG_LIVEPATCH */ | |
2215 | static int copy_module_elf(struct module *mod, struct load_info *info) | |
2216 | { | |
2217 | return 0; | |
2218 | } | |
2219 | ||
2220 | static void free_module_elf(struct module *mod) | |
2221 | { | |
2222 | } | |
2223 | #endif /* CONFIG_LIVEPATCH */ | |
2224 | ||
be1f221c | 2225 | void __weak module_memfree(void *module_region) |
74e08fcf | 2226 | { |
1a7b7d92 RE |
2227 | /* |
2228 | * This memory may be RO, and freeing RO memory in an interrupt is not | |
2229 | * supported by vmalloc. | |
2230 | */ | |
2231 | WARN_ON(in_interrupt()); | |
74e08fcf JB |
2232 | vfree(module_region); |
2233 | } | |
2234 | ||
2235 | void __weak module_arch_cleanup(struct module *mod) | |
2236 | { | |
2237 | } | |
2238 | ||
d453cded RR |
2239 | void __weak module_arch_freeing_init(struct module *mod) |
2240 | { | |
2241 | } | |
2242 | ||
75676500 | 2243 | /* Free a module, remove from lists, etc. */ |
1da177e4 LT |
2244 | static void free_module(struct module *mod) |
2245 | { | |
7ead8b83 LZ |
2246 | trace_module_free(mod); |
2247 | ||
36b0360d | 2248 | mod_sysfs_teardown(mod); |
1da177e4 | 2249 | |
24b9f0d2 SS |
2250 | /* |
2251 | * We leave it in list to prevent duplicate loads, but make sure | |
2252 | * that noone uses it while it's being deconstructed. | |
2253 | */ | |
d3051b48 | 2254 | mutex_lock(&module_mutex); |
944a1fa0 | 2255 | mod->state = MODULE_STATE_UNFORMED; |
d3051b48 | 2256 | mutex_unlock(&module_mutex); |
944a1fa0 | 2257 | |
b82bab4b JB |
2258 | /* Remove dynamic debug info */ |
2259 | ddebug_remove_module(mod->name); | |
2260 | ||
1da177e4 LT |
2261 | /* Arch-specific cleanup. */ |
2262 | module_arch_cleanup(mod); | |
2263 | ||
2264 | /* Module unload stuff */ | |
2265 | module_unload_free(mod); | |
2266 | ||
e180a6b7 RR |
2267 | /* Free any allocated parameters. */ |
2268 | destroy_params(mod->kp, mod->num_kp); | |
2269 | ||
1ce15ef4 JY |
2270 | if (is_livepatch_module(mod)) |
2271 | free_module_elf(mod); | |
2272 | ||
944a1fa0 RR |
2273 | /* Now we can delete it from the lists */ |
2274 | mutex_lock(&module_mutex); | |
461e34ae MH |
2275 | /* Unlink carefully: kallsyms could be walking list. */ |
2276 | list_del_rcu(&mod->list); | |
93c2e105 | 2277 | mod_tree_remove(mod); |
0286b5ea | 2278 | /* Remove this module from bug list, this uses list_del_rcu */ |
461e34ae | 2279 | module_bug_cleanup(mod); |
0be964be | 2280 | /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */ |
cb2f5536 | 2281 | synchronize_rcu(); |
944a1fa0 RR |
2282 | mutex_unlock(&module_mutex); |
2283 | ||
85c898db | 2284 | /* This may be empty, but that's OK */ |
d453cded | 2285 | module_arch_freeing_init(mod); |
7523e4dc | 2286 | module_memfree(mod->init_layout.base); |
1da177e4 | 2287 | kfree(mod->args); |
259354de | 2288 | percpu_modfree(mod); |
9f85a4bb | 2289 | |
35a9393c | 2290 | /* Free lock-classes; relies on the preceding sync_rcu(). */ |
7523e4dc | 2291 | lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size); |
fbb9ce95 | 2292 | |
1da177e4 | 2293 | /* Finally, free the core (containing the module structure) */ |
7523e4dc | 2294 | module_memfree(mod->core_layout.base); |
1da177e4 LT |
2295 | } |
2296 | ||
2297 | void *__symbol_get(const char *symbol) | |
2298 | { | |
2299 | struct module *owner; | |
414fd31b | 2300 | const struct kernel_symbol *sym; |
1da177e4 | 2301 | |
24da1cbf | 2302 | preempt_disable(); |
ef1dac60 | 2303 | sym = find_symbol(symbol, &owner, NULL, NULL, true, true); |
414fd31b TA |
2304 | if (sym && strong_try_module_get(owner)) |
2305 | sym = NULL; | |
24da1cbf | 2306 | preempt_enable(); |
1da177e4 | 2307 | |
7290d580 | 2308 | return sym ? (void *)kernel_symbol_value(sym) : NULL; |
1da177e4 LT |
2309 | } |
2310 | EXPORT_SYMBOL_GPL(__symbol_get); | |
2311 | ||
eea8b54d AN |
2312 | /* |
2313 | * Ensure that an exported symbol [global namespace] does not already exist | |
02a3e59a | 2314 | * in the kernel or in some other module's exported symbol table. |
be593f4c RR |
2315 | * |
2316 | * You must hold the module_mutex. | |
eea8b54d | 2317 | */ |
2d25bc55 | 2318 | static int verify_exported_symbols(struct module *mod) |
eea8b54d | 2319 | { |
b211104d | 2320 | unsigned int i; |
eea8b54d | 2321 | struct module *owner; |
b211104d RR |
2322 | const struct kernel_symbol *s; |
2323 | struct { | |
2324 | const struct kernel_symbol *sym; | |
2325 | unsigned int num; | |
2326 | } arr[] = { | |
2327 | { mod->syms, mod->num_syms }, | |
2328 | { mod->gpl_syms, mod->num_gpl_syms }, | |
2329 | { mod->gpl_future_syms, mod->num_gpl_future_syms }, | |
f7f5b675 | 2330 | #ifdef CONFIG_UNUSED_SYMBOLS |
b211104d RR |
2331 | { mod->unused_syms, mod->num_unused_syms }, |
2332 | { mod->unused_gpl_syms, mod->num_unused_gpl_syms }, | |
f7f5b675 | 2333 | #endif |
b211104d | 2334 | }; |
eea8b54d | 2335 | |
b211104d RR |
2336 | for (i = 0; i < ARRAY_SIZE(arr); i++) { |
2337 | for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) { | |
7290d580 | 2338 | if (find_symbol(kernel_symbol_name(s), &owner, NULL, |
ef1dac60 | 2339 | NULL, true, false)) { |
bddb12b3 | 2340 | pr_err("%s: exports duplicate symbol %s" |
b211104d | 2341 | " (owned by %s)\n", |
7290d580 AB |
2342 | mod->name, kernel_symbol_name(s), |
2343 | module_name(owner)); | |
b211104d RR |
2344 | return -ENOEXEC; |
2345 | } | |
eea8b54d | 2346 | } |
b211104d RR |
2347 | } |
2348 | return 0; | |
eea8b54d AN |
2349 | } |
2350 | ||
c1df82e5 FS |
2351 | static bool ignore_undef_symbol(Elf_Half emachine, const char *name) |
2352 | { | |
2353 | /* | |
2354 | * On x86, PIC code and Clang non-PIC code may have call foo@PLT. GNU as | |
2355 | * before 2.37 produces an unreferenced _GLOBAL_OFFSET_TABLE_ on x86-64. | |
2356 | * i386 has a similar problem but may not deserve a fix. | |
2357 | * | |
2358 | * If we ever have to ignore many symbols, consider refactoring the code to | |
2359 | * only warn if referenced by a relocation. | |
2360 | */ | |
2361 | if (emachine == EM_386 || emachine == EM_X86_64) | |
2362 | return !strcmp(name, "_GLOBAL_OFFSET_TABLE_"); | |
2363 | return false; | |
2364 | } | |
2365 | ||
9a4b9708 | 2366 | /* Change all symbols so that st_value encodes the pointer directly. */ |
49668688 RR |
2367 | static int simplify_symbols(struct module *mod, const struct load_info *info) |
2368 | { | |
2369 | Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; | |
2370 | Elf_Sym *sym = (void *)symsec->sh_addr; | |
1da177e4 | 2371 | unsigned long secbase; |
49668688 | 2372 | unsigned int i; |
1da177e4 | 2373 | int ret = 0; |
414fd31b | 2374 | const struct kernel_symbol *ksym; |
1da177e4 | 2375 | |
49668688 RR |
2376 | for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) { |
2377 | const char *name = info->strtab + sym[i].st_name; | |
2378 | ||
1da177e4 LT |
2379 | switch (sym[i].st_shndx) { |
2380 | case SHN_COMMON: | |
80375980 JM |
2381 | /* Ignore common symbols */ |
2382 | if (!strncmp(name, "__gnu_lto", 9)) | |
2383 | break; | |
2384 | ||
24b9f0d2 SS |
2385 | /* |
2386 | * We compiled with -fno-common. These are not | |
2387 | * supposed to happen. | |
2388 | */ | |
5e124169 | 2389 | pr_debug("Common symbol: %s\n", name); |
6da0b565 | 2390 | pr_warn("%s: please compile with -fno-common\n", |
1da177e4 LT |
2391 | mod->name); |
2392 | ret = -ENOEXEC; | |
2393 | break; | |
2394 | ||
2395 | case SHN_ABS: | |
2396 | /* Don't need to do anything */ | |
5e124169 | 2397 | pr_debug("Absolute symbol: 0x%08lx\n", |
1da177e4 LT |
2398 | (long)sym[i].st_value); |
2399 | break; | |
2400 | ||
1ce15ef4 JY |
2401 | case SHN_LIVEPATCH: |
2402 | /* Livepatch symbols are resolved by livepatch */ | |
2403 | break; | |
2404 | ||
1da177e4 | 2405 | case SHN_UNDEF: |
49668688 | 2406 | ksym = resolve_symbol_wait(mod, info, name); |
1da177e4 | 2407 | /* Ok if resolved. */ |
9bea7f23 | 2408 | if (ksym && !IS_ERR(ksym)) { |
7290d580 | 2409 | sym[i].st_value = kernel_symbol_value(ksym); |
1da177e4 | 2410 | break; |
414fd31b TA |
2411 | } |
2412 | ||
c1df82e5 FS |
2413 | /* Ok if weak or ignored. */ |
2414 | if (!ksym && | |
2415 | (ELF_ST_BIND(sym[i].st_info) == STB_WEAK || | |
2416 | ignore_undef_symbol(info->hdr->e_machine, name))) | |
1da177e4 LT |
2417 | break; |
2418 | ||
9bea7f23 | 2419 | ret = PTR_ERR(ksym) ?: -ENOENT; |
62267e0e JD |
2420 | pr_warn("%s: Unknown symbol %s (err %d)\n", |
2421 | mod->name, name, ret); | |
1da177e4 LT |
2422 | break; |
2423 | ||
2424 | default: | |
2425 | /* Divert to percpu allocation if a percpu var. */ | |
49668688 | 2426 | if (sym[i].st_shndx == info->index.pcpu) |
259354de | 2427 | secbase = (unsigned long)mod_percpu(mod); |
1da177e4 | 2428 | else |
49668688 | 2429 | secbase = info->sechdrs[sym[i].st_shndx].sh_addr; |
1da177e4 LT |
2430 | sym[i].st_value += secbase; |
2431 | break; | |
2432 | } | |
2433 | } | |
2434 | ||
2435 | return ret; | |
2436 | } | |
2437 | ||
49668688 | 2438 | static int apply_relocations(struct module *mod, const struct load_info *info) |
22e268eb RR |
2439 | { |
2440 | unsigned int i; | |
2441 | int err = 0; | |
2442 | ||
2443 | /* Now do relocations. */ | |
49668688 RR |
2444 | for (i = 1; i < info->hdr->e_shnum; i++) { |
2445 | unsigned int infosec = info->sechdrs[i].sh_info; | |
22e268eb RR |
2446 | |
2447 | /* Not a valid relocation section? */ | |
49668688 | 2448 | if (infosec >= info->hdr->e_shnum) |
22e268eb RR |
2449 | continue; |
2450 | ||
2451 | /* Don't bother with non-allocated sections */ | |
49668688 | 2452 | if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC)) |
22e268eb RR |
2453 | continue; |
2454 | ||
1ce15ef4 | 2455 | if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH) |
7c8e2bdd JP |
2456 | err = klp_apply_section_relocs(mod, info->sechdrs, |
2457 | info->secstrings, | |
2458 | info->strtab, | |
2459 | info->index.sym, i, | |
2460 | NULL); | |
2461 | else if (info->sechdrs[i].sh_type == SHT_REL) | |
49668688 RR |
2462 | err = apply_relocate(info->sechdrs, info->strtab, |
2463 | info->index.sym, i, mod); | |
2464 | else if (info->sechdrs[i].sh_type == SHT_RELA) | |
2465 | err = apply_relocate_add(info->sechdrs, info->strtab, | |
2466 | info->index.sym, i, mod); | |
22e268eb RR |
2467 | if (err < 0) |
2468 | break; | |
2469 | } | |
2470 | return err; | |
2471 | } | |
2472 | ||
088af9a6 HD |
2473 | /* Additional bytes needed by arch in front of individual sections */ |
2474 | unsigned int __weak arch_mod_section_prepend(struct module *mod, | |
2475 | unsigned int section) | |
2476 | { | |
2477 | /* default implementation just returns zero */ | |
2478 | return 0; | |
2479 | } | |
2480 | ||
1da177e4 | 2481 | /* Update size with this section: return offset. */ |
088af9a6 HD |
2482 | static long get_offset(struct module *mod, unsigned int *size, |
2483 | Elf_Shdr *sechdr, unsigned int section) | |
1da177e4 LT |
2484 | { |
2485 | long ret; | |
2486 | ||
088af9a6 | 2487 | *size += arch_mod_section_prepend(mod, section); |
1da177e4 LT |
2488 | ret = ALIGN(*size, sechdr->sh_addralign ?: 1); |
2489 | *size = ret + sechdr->sh_size; | |
2490 | return ret; | |
2491 | } | |
2492 | ||
24b9f0d2 SS |
2493 | /* |
2494 | * Lay out the SHF_ALLOC sections in a way not dissimilar to how ld | |
2495 | * might -- code, read-only data, read-write data, small data. Tally | |
2496 | * sizes, and place the offsets into sh_entsize fields: high bit means it | |
2497 | * belongs in init. | |
2498 | */ | |
49668688 | 2499 | static void layout_sections(struct module *mod, struct load_info *info) |
1da177e4 LT |
2500 | { |
2501 | static unsigned long const masks[][2] = { | |
24b9f0d2 SS |
2502 | /* |
2503 | * NOTE: all executable code must be the first section | |
1da177e4 | 2504 | * in this array; otherwise modify the text_size |
24b9f0d2 SS |
2505 | * finder in the two loops below |
2506 | */ | |
1da177e4 LT |
2507 | { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL }, |
2508 | { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL }, | |
444d13ff | 2509 | { SHF_RO_AFTER_INIT | SHF_ALLOC, ARCH_SHF_SMALL }, |
1da177e4 LT |
2510 | { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL }, |
2511 | { ARCH_SHF_SMALL | SHF_ALLOC, 0 } | |
2512 | }; | |
2513 | unsigned int m, i; | |
2514 | ||
49668688 RR |
2515 | for (i = 0; i < info->hdr->e_shnum; i++) |
2516 | info->sechdrs[i].sh_entsize = ~0UL; | |
1da177e4 | 2517 | |
5e124169 | 2518 | pr_debug("Core section allocation order:\n"); |
1da177e4 | 2519 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { |
49668688 RR |
2520 | for (i = 0; i < info->hdr->e_shnum; ++i) { |
2521 | Elf_Shdr *s = &info->sechdrs[i]; | |
2522 | const char *sname = info->secstrings + s->sh_name; | |
1da177e4 LT |
2523 | |
2524 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
2525 | || (s->sh_flags & masks[m][1]) | |
2526 | || s->sh_entsize != ~0UL | |
23189766 | 2527 | || module_init_section(sname)) |
1da177e4 | 2528 | continue; |
7523e4dc | 2529 | s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i); |
5e124169 | 2530 | pr_debug("\t%s\n", sname); |
1da177e4 | 2531 | } |
84e1c6bb MC |
2532 | switch (m) { |
2533 | case 0: /* executable */ | |
7523e4dc RR |
2534 | mod->core_layout.size = debug_align(mod->core_layout.size); |
2535 | mod->core_layout.text_size = mod->core_layout.size; | |
84e1c6bb MC |
2536 | break; |
2537 | case 1: /* RO: text and ro-data */ | |
7523e4dc RR |
2538 | mod->core_layout.size = debug_align(mod->core_layout.size); |
2539 | mod->core_layout.ro_size = mod->core_layout.size; | |
84e1c6bb | 2540 | break; |
444d13ff JY |
2541 | case 2: /* RO after init */ |
2542 | mod->core_layout.size = debug_align(mod->core_layout.size); | |
2543 | mod->core_layout.ro_after_init_size = mod->core_layout.size; | |
2544 | break; | |
2545 | case 4: /* whole core */ | |
7523e4dc | 2546 | mod->core_layout.size = debug_align(mod->core_layout.size); |
84e1c6bb MC |
2547 | break; |
2548 | } | |
1da177e4 LT |
2549 | } |
2550 | ||
5e124169 | 2551 | pr_debug("Init section allocation order:\n"); |
1da177e4 | 2552 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { |
49668688 RR |
2553 | for (i = 0; i < info->hdr->e_shnum; ++i) { |
2554 | Elf_Shdr *s = &info->sechdrs[i]; | |
2555 | const char *sname = info->secstrings + s->sh_name; | |
1da177e4 LT |
2556 | |
2557 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
2558 | || (s->sh_flags & masks[m][1]) | |
2559 | || s->sh_entsize != ~0UL | |
23189766 | 2560 | || !module_init_section(sname)) |
1da177e4 | 2561 | continue; |
7523e4dc | 2562 | s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i) |
1da177e4 | 2563 | | INIT_OFFSET_MASK); |
5e124169 | 2564 | pr_debug("\t%s\n", sname); |
1da177e4 | 2565 | } |
84e1c6bb MC |
2566 | switch (m) { |
2567 | case 0: /* executable */ | |
7523e4dc RR |
2568 | mod->init_layout.size = debug_align(mod->init_layout.size); |
2569 | mod->init_layout.text_size = mod->init_layout.size; | |
84e1c6bb MC |
2570 | break; |
2571 | case 1: /* RO: text and ro-data */ | |
7523e4dc RR |
2572 | mod->init_layout.size = debug_align(mod->init_layout.size); |
2573 | mod->init_layout.ro_size = mod->init_layout.size; | |
84e1c6bb | 2574 | break; |
444d13ff JY |
2575 | case 2: |
2576 | /* | |
2577 | * RO after init doesn't apply to init_layout (only | |
2578 | * core_layout), so it just takes the value of ro_size. | |
2579 | */ | |
2580 | mod->init_layout.ro_after_init_size = mod->init_layout.ro_size; | |
2581 | break; | |
2582 | case 4: /* whole init */ | |
7523e4dc | 2583 | mod->init_layout.size = debug_align(mod->init_layout.size); |
84e1c6bb MC |
2584 | break; |
2585 | } | |
1da177e4 LT |
2586 | } |
2587 | } | |
2588 | ||
1da177e4 LT |
2589 | static void set_license(struct module *mod, const char *license) |
2590 | { | |
2591 | if (!license) | |
2592 | license = "unspecified"; | |
2593 | ||
fa3ba2e8 | 2594 | if (!license_is_gpl_compatible(license)) { |
25ddbb18 | 2595 | if (!test_taint(TAINT_PROPRIETARY_MODULE)) |
bddb12b3 AM |
2596 | pr_warn("%s: module license '%s' taints kernel.\n", |
2597 | mod->name, license); | |
373d4d09 RR |
2598 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
2599 | LOCKDEP_NOW_UNRELIABLE); | |
1da177e4 LT |
2600 | } |
2601 | } | |
2602 | ||
2603 | /* Parse tag=value strings from .modinfo section */ | |
2604 | static char *next_string(char *string, unsigned long *secsize) | |
2605 | { | |
2606 | /* Skip non-zero chars */ | |
2607 | while (string[0]) { | |
2608 | string++; | |
2609 | if ((*secsize)-- <= 1) | |
2610 | return NULL; | |
2611 | } | |
2612 | ||
2613 | /* Skip any zero padding. */ | |
2614 | while (!string[0]) { | |
2615 | string++; | |
2616 | if ((*secsize)-- <= 1) | |
2617 | return NULL; | |
2618 | } | |
2619 | return string; | |
2620 | } | |
2621 | ||
c5e4a062 MM |
2622 | static char *get_next_modinfo(const struct load_info *info, const char *tag, |
2623 | char *prev) | |
1da177e4 LT |
2624 | { |
2625 | char *p; | |
2626 | unsigned int taglen = strlen(tag); | |
49668688 RR |
2627 | Elf_Shdr *infosec = &info->sechdrs[info->index.info]; |
2628 | unsigned long size = infosec->sh_size; | |
1da177e4 | 2629 | |
5fdc7db6 JY |
2630 | /* |
2631 | * get_modinfo() calls made before rewrite_section_headers() | |
2632 | * must use sh_offset, as sh_addr isn't set! | |
2633 | */ | |
c5e4a062 MM |
2634 | char *modinfo = (char *)info->hdr + infosec->sh_offset; |
2635 | ||
2636 | if (prev) { | |
2637 | size -= prev - modinfo; | |
2638 | modinfo = next_string(prev, &size); | |
2639 | } | |
2640 | ||
2641 | for (p = modinfo; p; p = next_string(p, &size)) { | |
1da177e4 LT |
2642 | if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') |
2643 | return p + taglen + 1; | |
2644 | } | |
2645 | return NULL; | |
2646 | } | |
2647 | ||
c5e4a062 MM |
2648 | static char *get_modinfo(const struct load_info *info, const char *tag) |
2649 | { | |
2650 | return get_next_modinfo(info, tag, NULL); | |
2651 | } | |
2652 | ||
49668688 | 2653 | static void setup_modinfo(struct module *mod, struct load_info *info) |
c988d2b2 MD |
2654 | { |
2655 | struct module_attribute *attr; | |
2656 | int i; | |
2657 | ||
2658 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
2659 | if (attr->setup) | |
49668688 | 2660 | attr->setup(mod, get_modinfo(info, attr->attr.name)); |
c988d2b2 MD |
2661 | } |
2662 | } | |
c988d2b2 | 2663 | |
a263f776 RR |
2664 | static void free_modinfo(struct module *mod) |
2665 | { | |
2666 | struct module_attribute *attr; | |
2667 | int i; | |
2668 | ||
2669 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
2670 | if (attr->free) | |
2671 | attr->free(mod); | |
2672 | } | |
2673 | } | |
2674 | ||
1da177e4 | 2675 | #ifdef CONFIG_KALLSYMS |
15bba37d | 2676 | |
2d25bc55 JY |
2677 | /* Lookup exported symbol in given range of kernel_symbols */ |
2678 | static const struct kernel_symbol *lookup_exported_symbol(const char *name, | |
2679 | const struct kernel_symbol *start, | |
2680 | const struct kernel_symbol *stop) | |
15bba37d | 2681 | { |
9d63487f AIB |
2682 | return bsearch(name, start, stop - start, |
2683 | sizeof(struct kernel_symbol), cmp_name); | |
15bba37d WC |
2684 | } |
2685 | ||
ca4787b7 TA |
2686 | static int is_exported(const char *name, unsigned long value, |
2687 | const struct module *mod) | |
1da177e4 | 2688 | { |
ca4787b7 TA |
2689 | const struct kernel_symbol *ks; |
2690 | if (!mod) | |
2d25bc55 | 2691 | ks = lookup_exported_symbol(name, __start___ksymtab, __stop___ksymtab); |
3fd6805f | 2692 | else |
2d25bc55 JY |
2693 | ks = lookup_exported_symbol(name, mod->syms, mod->syms + mod->num_syms); |
2694 | ||
7290d580 | 2695 | return ks != NULL && kernel_symbol_value(ks) == value; |
1da177e4 LT |
2696 | } |
2697 | ||
2698 | /* As per nm */ | |
eded41c1 | 2699 | static char elf_type(const Elf_Sym *sym, const struct load_info *info) |
1da177e4 | 2700 | { |
eded41c1 RR |
2701 | const Elf_Shdr *sechdrs = info->sechdrs; |
2702 | ||
1da177e4 LT |
2703 | if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { |
2704 | if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) | |
2705 | return 'v'; | |
2706 | else | |
2707 | return 'w'; | |
2708 | } | |
2709 | if (sym->st_shndx == SHN_UNDEF) | |
2710 | return 'U'; | |
e0224418 | 2711 | if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu) |
1da177e4 LT |
2712 | return 'a'; |
2713 | if (sym->st_shndx >= SHN_LORESERVE) | |
2714 | return '?'; | |
2715 | if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) | |
2716 | return 't'; | |
2717 | if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC | |
2718 | && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { | |
2719 | if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) | |
2720 | return 'r'; | |
2721 | else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
2722 | return 'g'; | |
2723 | else | |
2724 | return 'd'; | |
2725 | } | |
2726 | if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { | |
2727 | if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
2728 | return 's'; | |
2729 | else | |
2730 | return 'b'; | |
2731 | } | |
eded41c1 RR |
2732 | if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name, |
2733 | ".debug")) { | |
1da177e4 | 2734 | return 'n'; |
eded41c1 | 2735 | } |
1da177e4 LT |
2736 | return '?'; |
2737 | } | |
2738 | ||
4a496226 | 2739 | static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs, |
e0224418 | 2740 | unsigned int shnum, unsigned int pcpundx) |
4a496226 JB |
2741 | { |
2742 | const Elf_Shdr *sec; | |
2743 | ||
2744 | if (src->st_shndx == SHN_UNDEF | |
2745 | || src->st_shndx >= shnum | |
2746 | || !src->st_name) | |
2747 | return false; | |
2748 | ||
e0224418 MB |
2749 | #ifdef CONFIG_KALLSYMS_ALL |
2750 | if (src->st_shndx == pcpundx) | |
2751 | return true; | |
2752 | #endif | |
2753 | ||
4a496226 JB |
2754 | sec = sechdrs + src->st_shndx; |
2755 | if (!(sec->sh_flags & SHF_ALLOC) | |
2756 | #ifndef CONFIG_KALLSYMS_ALL | |
2757 | || !(sec->sh_flags & SHF_EXECINSTR) | |
2758 | #endif | |
2759 | || (sec->sh_entsize & INIT_OFFSET_MASK)) | |
2760 | return false; | |
2761 | ||
2762 | return true; | |
2763 | } | |
2764 | ||
48fd1188 KC |
2765 | /* |
2766 | * We only allocate and copy the strings needed by the parts of symtab | |
2767 | * we keep. This is simple, but has the effect of making multiple | |
2768 | * copies of duplicates. We could be more sophisticated, see | |
2769 | * linux-kernel thread starting with | |
2770 | * <73defb5e4bca04a6431392cc341112b1@localhost>. | |
2771 | */ | |
49668688 | 2772 | static void layout_symtab(struct module *mod, struct load_info *info) |
4a496226 | 2773 | { |
49668688 RR |
2774 | Elf_Shdr *symsect = info->sechdrs + info->index.sym; |
2775 | Elf_Shdr *strsect = info->sechdrs + info->index.str; | |
4a496226 | 2776 | const Elf_Sym *src; |
54523ec7 | 2777 | unsigned int i, nsrc, ndst, strtab_size = 0; |
4a496226 JB |
2778 | |
2779 | /* Put symbol section at end of init part of module. */ | |
2780 | symsect->sh_flags |= SHF_ALLOC; | |
7523e4dc | 2781 | symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect, |
49668688 | 2782 | info->index.sym) | INIT_OFFSET_MASK; |
5e124169 | 2783 | pr_debug("\t%s\n", info->secstrings + symsect->sh_name); |
4a496226 | 2784 | |
49668688 | 2785 | src = (void *)info->hdr + symsect->sh_offset; |
4a496226 | 2786 | nsrc = symsect->sh_size / sizeof(*src); |
70b1e916 | 2787 | |
48fd1188 | 2788 | /* Compute total space required for the core symbols' strtab. */ |
59ef28b1 | 2789 | for (ndst = i = 0; i < nsrc; i++) { |
1ce15ef4 | 2790 | if (i == 0 || is_livepatch_module(mod) || |
e0224418 MB |
2791 | is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, |
2792 | info->index.pcpu)) { | |
59ef28b1 | 2793 | strtab_size += strlen(&info->strtab[src[i].st_name])+1; |
48fd1188 | 2794 | ndst++; |
554bdfe5 | 2795 | } |
59ef28b1 | 2796 | } |
4a496226 JB |
2797 | |
2798 | /* Append room for core symbols at end of core part. */ | |
7523e4dc RR |
2799 | info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1); |
2800 | info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym); | |
2801 | mod->core_layout.size += strtab_size; | |
1c7651f4 EL |
2802 | info->core_typeoffs = mod->core_layout.size; |
2803 | mod->core_layout.size += ndst * sizeof(char); | |
7523e4dc | 2804 | mod->core_layout.size = debug_align(mod->core_layout.size); |
4a496226 | 2805 | |
554bdfe5 JB |
2806 | /* Put string table section at end of init part of module. */ |
2807 | strsect->sh_flags |= SHF_ALLOC; | |
7523e4dc | 2808 | strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect, |
49668688 | 2809 | info->index.str) | INIT_OFFSET_MASK; |
5e124169 | 2810 | pr_debug("\t%s\n", info->secstrings + strsect->sh_name); |
8244062e RR |
2811 | |
2812 | /* We'll tack temporary mod_kallsyms on the end. */ | |
2813 | mod->init_layout.size = ALIGN(mod->init_layout.size, | |
2814 | __alignof__(struct mod_kallsyms)); | |
2815 | info->mod_kallsyms_init_off = mod->init_layout.size; | |
2816 | mod->init_layout.size += sizeof(struct mod_kallsyms); | |
1c7651f4 EL |
2817 | info->init_typeoffs = mod->init_layout.size; |
2818 | mod->init_layout.size += nsrc * sizeof(char); | |
8244062e | 2819 | mod->init_layout.size = debug_align(mod->init_layout.size); |
4a496226 JB |
2820 | } |
2821 | ||
8244062e RR |
2822 | /* |
2823 | * We use the full symtab and strtab which layout_symtab arranged to | |
2824 | * be appended to the init section. Later we switch to the cut-down | |
2825 | * core-only ones. | |
2826 | */ | |
811d66a0 | 2827 | static void add_kallsyms(struct module *mod, const struct load_info *info) |
1da177e4 | 2828 | { |
4a496226 JB |
2829 | unsigned int i, ndst; |
2830 | const Elf_Sym *src; | |
2831 | Elf_Sym *dst; | |
554bdfe5 | 2832 | char *s; |
eded41c1 | 2833 | Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; |
1da177e4 | 2834 | |
8244062e RR |
2835 | /* Set up to point into init section. */ |
2836 | mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off; | |
2837 | ||
2838 | mod->kallsyms->symtab = (void *)symsec->sh_addr; | |
2839 | mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym); | |
511ca6ae | 2840 | /* Make sure we get permanent strtab: don't use info->strtab. */ |
8244062e | 2841 | mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr; |
1c7651f4 | 2842 | mod->kallsyms->typetab = mod->init_layout.base + info->init_typeoffs; |
1da177e4 | 2843 | |
1c7651f4 EL |
2844 | /* |
2845 | * Now populate the cut down core kallsyms for after init | |
2846 | * and set types up while we still have access to sections. | |
2847 | */ | |
8244062e RR |
2848 | mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs; |
2849 | mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs; | |
1c7651f4 | 2850 | mod->core_kallsyms.typetab = mod->core_layout.base + info->core_typeoffs; |
8244062e RR |
2851 | src = mod->kallsyms->symtab; |
2852 | for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) { | |
1c7651f4 | 2853 | mod->kallsyms->typetab[i] = elf_type(src + i, info); |
1ce15ef4 | 2854 | if (i == 0 || is_livepatch_module(mod) || |
e0224418 MB |
2855 | is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, |
2856 | info->index.pcpu)) { | |
1c7651f4 EL |
2857 | mod->core_kallsyms.typetab[ndst] = |
2858 | mod->kallsyms->typetab[i]; | |
59ef28b1 | 2859 | dst[ndst] = src[i]; |
8244062e RR |
2860 | dst[ndst++].st_name = s - mod->core_kallsyms.strtab; |
2861 | s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name], | |
59ef28b1 RR |
2862 | KSYM_NAME_LEN) + 1; |
2863 | } | |
4a496226 | 2864 | } |
8244062e | 2865 | mod->core_kallsyms.num_symtab = ndst; |
1da177e4 LT |
2866 | } |
2867 | #else | |
49668688 | 2868 | static inline void layout_symtab(struct module *mod, struct load_info *info) |
4a496226 JB |
2869 | { |
2870 | } | |
3ae91c21 | 2871 | |
abbce906 | 2872 | static void add_kallsyms(struct module *mod, const struct load_info *info) |
1da177e4 LT |
2873 | { |
2874 | } | |
2875 | #endif /* CONFIG_KALLSYMS */ | |
2876 | ||
52796312 | 2877 | static void dynamic_debug_setup(struct module *mod, struct _ddebug *debug, unsigned int num) |
346e15be | 2878 | { |
811d66a0 RR |
2879 | if (!debug) |
2880 | return; | |
513770f5 | 2881 | ddebug_add_module(debug, num, mod->name); |
5e458cc0 | 2882 | } |
346e15be | 2883 | |
52796312 | 2884 | static void dynamic_debug_remove(struct module *mod, struct _ddebug *debug) |
ff49d74a YS |
2885 | { |
2886 | if (debug) | |
52796312 | 2887 | ddebug_remove_module(mod->name); |
ff49d74a YS |
2888 | } |
2889 | ||
74e08fcf JB |
2890 | void * __weak module_alloc(unsigned long size) |
2891 | { | |
7a0e27b2 CH |
2892 | return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END, |
2893 | GFP_KERNEL, PAGE_KERNEL_EXEC, VM_FLUSH_RESET_PERMS, | |
a3a66c38 | 2894 | NUMA_NO_NODE, __builtin_return_address(0)); |
74e08fcf JB |
2895 | } |
2896 | ||
23189766 VW |
2897 | bool __weak module_init_section(const char *name) |
2898 | { | |
2899 | return strstarts(name, ".init"); | |
2900 | } | |
2901 | ||
38b37d63 MS |
2902 | bool __weak module_exit_section(const char *name) |
2903 | { | |
2904 | return strstarts(name, ".exit"); | |
2905 | } | |
2906 | ||
4f2294b6 | 2907 | #ifdef CONFIG_DEBUG_KMEMLEAK |
49668688 RR |
2908 | static void kmemleak_load_module(const struct module *mod, |
2909 | const struct load_info *info) | |
4f2294b6 CM |
2910 | { |
2911 | unsigned int i; | |
2912 | ||
2913 | /* only scan the sections containing data */ | |
c017b4be | 2914 | kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL); |
4f2294b6 | 2915 | |
49668688 | 2916 | for (i = 1; i < info->hdr->e_shnum; i++) { |
06c9494c SR |
2917 | /* Scan all writable sections that's not executable */ |
2918 | if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) || | |
2919 | !(info->sechdrs[i].sh_flags & SHF_WRITE) || | |
2920 | (info->sechdrs[i].sh_flags & SHF_EXECINSTR)) | |
4f2294b6 CM |
2921 | continue; |
2922 | ||
49668688 RR |
2923 | kmemleak_scan_area((void *)info->sechdrs[i].sh_addr, |
2924 | info->sechdrs[i].sh_size, GFP_KERNEL); | |
4f2294b6 CM |
2925 | } |
2926 | } | |
2927 | #else | |
49668688 RR |
2928 | static inline void kmemleak_load_module(const struct module *mod, |
2929 | const struct load_info *info) | |
4f2294b6 CM |
2930 | { |
2931 | } | |
2932 | #endif | |
2933 | ||
106a4ee2 | 2934 | #ifdef CONFIG_MODULE_SIG |
bca014ca | 2935 | static int module_sig_check(struct load_info *info, int flags) |
106a4ee2 | 2936 | { |
49fcf732 | 2937 | int err = -ENODATA; |
34e1169d | 2938 | const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; |
49fcf732 | 2939 | const char *reason; |
34e1169d | 2940 | const void *mod = info->hdr; |
caabe240 | 2941 | |
bca014ca BH |
2942 | /* |
2943 | * Require flags == 0, as a module with version information | |
2944 | * removed is no longer the module that was signed | |
2945 | */ | |
2946 | if (flags == 0 && | |
2947 | info->len > markerlen && | |
34e1169d | 2948 | memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) { |
caabe240 | 2949 | /* We truncate the module to discard the signature */ |
34e1169d | 2950 | info->len -= markerlen; |
f314dfea | 2951 | err = mod_verify_sig(mod, info); |
076aa52e SS |
2952 | if (!err) { |
2953 | info->sig_ok = true; | |
2954 | return 0; | |
2955 | } | |
106a4ee2 RR |
2956 | } |
2957 | ||
076aa52e SS |
2958 | /* |
2959 | * We don't permit modules to be loaded into the trusted kernels | |
2960 | * without a valid signature on them, but if we're not enforcing, | |
2961 | * certain errors are non-fatal. | |
2962 | */ | |
49fcf732 | 2963 | switch (err) { |
49fcf732 | 2964 | case -ENODATA: |
705e9195 | 2965 | reason = "unsigned module"; |
10ccd1ab | 2966 | break; |
49fcf732 | 2967 | case -ENOPKG: |
705e9195 | 2968 | reason = "module with unsupported crypto"; |
10ccd1ab | 2969 | break; |
49fcf732 | 2970 | case -ENOKEY: |
705e9195 | 2971 | reason = "module with unavailable key"; |
10ccd1ab | 2972 | break; |
49fcf732 | 2973 | |
49fcf732 | 2974 | default: |
076aa52e SS |
2975 | /* |
2976 | * All other errors are fatal, including lack of memory, | |
2977 | * unparseable signatures, and signature check failures -- | |
2978 | * even if signatures aren't required. | |
2979 | */ | |
49fcf732 DH |
2980 | return err; |
2981 | } | |
10ccd1ab SS |
2982 | |
2983 | if (is_module_sig_enforced()) { | |
b484304a | 2984 | pr_notice("Loading of %s is rejected\n", reason); |
10ccd1ab SS |
2985 | return -EKEYREJECTED; |
2986 | } | |
2987 | ||
2988 | return security_locked_down(LOCKDOWN_MODULE_SIGNATURE); | |
106a4ee2 RR |
2989 | } |
2990 | #else /* !CONFIG_MODULE_SIG */ | |
bca014ca | 2991 | static int module_sig_check(struct load_info *info, int flags) |
106a4ee2 RR |
2992 | { |
2993 | return 0; | |
2994 | } | |
2995 | #endif /* !CONFIG_MODULE_SIG */ | |
2996 | ||
b484304a | 2997 | static int validate_section_offset(struct load_info *info, Elf_Shdr *shdr) |
40dd2560 | 2998 | { |
b484304a FL |
2999 | unsigned long secend; |
3000 | ||
3001 | /* | |
3002 | * Check for both overflow and offset/size being | |
3003 | * too large. | |
3004 | */ | |
3005 | secend = shdr->sh_offset + shdr->sh_size; | |
3006 | if (secend < shdr->sh_offset || secend > info->len) | |
3007 | return -ENOEXEC; | |
3008 | ||
3009 | return 0; | |
3010 | } | |
3011 | ||
3012 | /* | |
3013 | * Sanity checks against invalid binaries, wrong arch, weird elf version. | |
3014 | * | |
3015 | * Also do basic validity checks against section offsets and sizes, the | |
3016 | * section name string table, and the indices used for it (sh_name). | |
3017 | */ | |
3018 | static int elf_validity_check(struct load_info *info) | |
3019 | { | |
3020 | unsigned int i; | |
3021 | Elf_Shdr *shdr, *strhdr; | |
3022 | int err; | |
3023 | ||
34e1169d KC |
3024 | if (info->len < sizeof(*(info->hdr))) |
3025 | return -ENOEXEC; | |
3026 | ||
3027 | if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0 | |
3028 | || info->hdr->e_type != ET_REL | |
3029 | || !elf_check_arch(info->hdr) | |
3030 | || info->hdr->e_shentsize != sizeof(Elf_Shdr)) | |
3031 | return -ENOEXEC; | |
3032 | ||
b484304a FL |
3033 | /* |
3034 | * e_shnum is 16 bits, and sizeof(Elf_Shdr) is | |
3035 | * known and small. So e_shnum * sizeof(Elf_Shdr) | |
3036 | * will not overflow unsigned long on any platform. | |
3037 | */ | |
34e1169d KC |
3038 | if (info->hdr->e_shoff >= info->len |
3039 | || (info->hdr->e_shnum * sizeof(Elf_Shdr) > | |
3040 | info->len - info->hdr->e_shoff)) | |
3041 | return -ENOEXEC; | |
40dd2560 | 3042 | |
b484304a FL |
3043 | info->sechdrs = (void *)info->hdr + info->hdr->e_shoff; |
3044 | ||
3045 | /* | |
3046 | * Verify if the section name table index is valid. | |
3047 | */ | |
3048 | if (info->hdr->e_shstrndx == SHN_UNDEF | |
3049 | || info->hdr->e_shstrndx >= info->hdr->e_shnum) | |
3050 | return -ENOEXEC; | |
3051 | ||
3052 | strhdr = &info->sechdrs[info->hdr->e_shstrndx]; | |
3053 | err = validate_section_offset(info, strhdr); | |
3054 | if (err < 0) | |
3055 | return err; | |
3056 | ||
3057 | /* | |
3058 | * The section name table must be NUL-terminated, as required | |
3059 | * by the spec. This makes strcmp and pr_* calls that access | |
3060 | * strings in the section safe. | |
3061 | */ | |
3062 | info->secstrings = (void *)info->hdr + strhdr->sh_offset; | |
3063 | if (info->secstrings[strhdr->sh_size - 1] != '\0') | |
3064 | return -ENOEXEC; | |
3065 | ||
3066 | /* | |
3067 | * The code assumes that section 0 has a length of zero and | |
3068 | * an addr of zero, so check for it. | |
3069 | */ | |
3070 | if (info->sechdrs[0].sh_type != SHT_NULL | |
3071 | || info->sechdrs[0].sh_size != 0 | |
3072 | || info->sechdrs[0].sh_addr != 0) | |
3073 | return -ENOEXEC; | |
3074 | ||
3075 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
3076 | shdr = &info->sechdrs[i]; | |
3077 | switch (shdr->sh_type) { | |
3078 | case SHT_NULL: | |
3079 | case SHT_NOBITS: | |
3080 | continue; | |
3081 | case SHT_SYMTAB: | |
3082 | if (shdr->sh_link == SHN_UNDEF | |
3083 | || shdr->sh_link >= info->hdr->e_shnum) | |
3084 | return -ENOEXEC; | |
3085 | fallthrough; | |
3086 | default: | |
3087 | err = validate_section_offset(info, shdr); | |
3088 | if (err < 0) { | |
3089 | pr_err("Invalid ELF section in module (section %u type %u)\n", | |
3090 | i, shdr->sh_type); | |
3091 | return err; | |
3092 | } | |
3093 | ||
3094 | if (shdr->sh_flags & SHF_ALLOC) { | |
3095 | if (shdr->sh_name >= strhdr->sh_size) { | |
3096 | pr_err("Invalid ELF section name in module (section %u type %u)\n", | |
3097 | i, shdr->sh_type); | |
3098 | return -ENOEXEC; | |
3099 | } | |
3100 | } | |
3101 | break; | |
3102 | } | |
3103 | } | |
3104 | ||
34e1169d KC |
3105 | return 0; |
3106 | } | |
3107 | ||
3afe9f84 LT |
3108 | #define COPY_CHUNK_SIZE (16*PAGE_SIZE) |
3109 | ||
3110 | static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len) | |
3111 | { | |
3112 | do { | |
3113 | unsigned long n = min(len, COPY_CHUNK_SIZE); | |
3114 | ||
3115 | if (copy_from_user(dst, usrc, n) != 0) | |
3116 | return -EFAULT; | |
3117 | cond_resched(); | |
3118 | dst += n; | |
3119 | usrc += n; | |
3120 | len -= n; | |
3121 | } while (len); | |
3122 | return 0; | |
3123 | } | |
3124 | ||
1ce15ef4 | 3125 | #ifdef CONFIG_LIVEPATCH |
2992ef29 | 3126 | static int check_modinfo_livepatch(struct module *mod, struct load_info *info) |
1ce15ef4 | 3127 | { |
2992ef29 JP |
3128 | if (get_modinfo(info, "livepatch")) { |
3129 | mod->klp = true; | |
3130 | add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK); | |
7598d167 JL |
3131 | pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n", |
3132 | mod->name); | |
2992ef29 | 3133 | } |
1ce15ef4 JY |
3134 | |
3135 | return 0; | |
3136 | } | |
3137 | #else /* !CONFIG_LIVEPATCH */ | |
2992ef29 | 3138 | static int check_modinfo_livepatch(struct module *mod, struct load_info *info) |
1ce15ef4 JY |
3139 | { |
3140 | if (get_modinfo(info, "livepatch")) { | |
3141 | pr_err("%s: module is marked as livepatch module, but livepatch support is disabled", | |
3142 | mod->name); | |
3143 | return -ENOEXEC; | |
3144 | } | |
3145 | ||
3146 | return 0; | |
3147 | } | |
3148 | #endif /* CONFIG_LIVEPATCH */ | |
3149 | ||
caf7501a AK |
3150 | static void check_modinfo_retpoline(struct module *mod, struct load_info *info) |
3151 | { | |
3152 | if (retpoline_module_ok(get_modinfo(info, "retpoline"))) | |
3153 | return; | |
3154 | ||
3155 | pr_warn("%s: loading module not compiled with retpoline compiler.\n", | |
3156 | mod->name); | |
3157 | } | |
3158 | ||
34e1169d KC |
3159 | /* Sets info->hdr and info->len. */ |
3160 | static int copy_module_from_user(const void __user *umod, unsigned long len, | |
3161 | struct load_info *info) | |
40dd2560 RR |
3162 | { |
3163 | int err; | |
40dd2560 | 3164 | |
34e1169d KC |
3165 | info->len = len; |
3166 | if (info->len < sizeof(*(info->hdr))) | |
40dd2560 RR |
3167 | return -ENOEXEC; |
3168 | ||
38f90173 | 3169 | err = security_kernel_load_data(LOADING_MODULE, true); |
2e72d51b KC |
3170 | if (err) |
3171 | return err; | |
3172 | ||
40dd2560 | 3173 | /* Suck in entire file: we'll want most of it. */ |
88dca4ca | 3174 | info->hdr = __vmalloc(info->len, GFP_KERNEL | __GFP_NOWARN); |
34e1169d | 3175 | if (!info->hdr) |
40dd2560 RR |
3176 | return -ENOMEM; |
3177 | ||
3afe9f84 | 3178 | if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) { |
38f90173 KC |
3179 | err = -EFAULT; |
3180 | goto out; | |
40dd2560 RR |
3181 | } |
3182 | ||
38f90173 KC |
3183 | err = security_kernel_post_load_data((char *)info->hdr, info->len, |
3184 | LOADING_MODULE, "init_module"); | |
3185 | out: | |
3186 | if (err) | |
3187 | vfree(info->hdr); | |
3188 | ||
3189 | return err; | |
34e1169d KC |
3190 | } |
3191 | ||
d913188c RR |
3192 | static void free_copy(struct load_info *info) |
3193 | { | |
d913188c RR |
3194 | vfree(info->hdr); |
3195 | } | |
3196 | ||
2f3238ae | 3197 | static int rewrite_section_headers(struct load_info *info, int flags) |
8b5f61a7 RR |
3198 | { |
3199 | unsigned int i; | |
3200 | ||
3201 | /* This should always be true, but let's be sure. */ | |
3202 | info->sechdrs[0].sh_addr = 0; | |
3203 | ||
3204 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
3205 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
8b5f61a7 | 3206 | |
24b9f0d2 SS |
3207 | /* |
3208 | * Mark all sections sh_addr with their address in the | |
3209 | * temporary image. | |
3210 | */ | |
8b5f61a7 RR |
3211 | shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset; |
3212 | ||
3213 | #ifndef CONFIG_MODULE_UNLOAD | |
3214 | /* Don't load .exit sections */ | |
38b37d63 | 3215 | if (module_exit_section(info->secstrings+shdr->sh_name)) |
8b5f61a7 RR |
3216 | shdr->sh_flags &= ~(unsigned long)SHF_ALLOC; |
3217 | #endif | |
8b5f61a7 | 3218 | } |
d6df72a0 RR |
3219 | |
3220 | /* Track but don't keep modinfo and version sections. */ | |
3e2e857f | 3221 | info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC; |
d6df72a0 | 3222 | info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC; |
3e2e857f | 3223 | |
8b5f61a7 RR |
3224 | return 0; |
3225 | } | |
3226 | ||
3264d3f9 LT |
3227 | /* |
3228 | * Set up our basic convenience variables (pointers to section headers, | |
3229 | * search for module section index etc), and do some basic section | |
3230 | * verification. | |
3231 | * | |
81a0abd9 JY |
3232 | * Set info->mod to the temporary copy of the module in info->hdr. The final one |
3233 | * will be allocated in move_module(). | |
3264d3f9 | 3234 | */ |
81a0abd9 | 3235 | static int setup_load_info(struct load_info *info, int flags) |
3264d3f9 LT |
3236 | { |
3237 | unsigned int i; | |
3264d3f9 | 3238 | |
5fdc7db6 JY |
3239 | /* Try to find a name early so we can log errors with a module name */ |
3240 | info->index.info = find_sec(info, ".modinfo"); | |
708e0ada | 3241 | if (info->index.info) |
5fdc7db6 | 3242 | info->name = get_modinfo(info, "name"); |
3264d3f9 | 3243 | |
8b5f61a7 RR |
3244 | /* Find internal symbols and strings. */ |
3245 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
3264d3f9 LT |
3246 | if (info->sechdrs[i].sh_type == SHT_SYMTAB) { |
3247 | info->index.sym = i; | |
3248 | info->index.str = info->sechdrs[i].sh_link; | |
8b5f61a7 RR |
3249 | info->strtab = (char *)info->hdr |
3250 | + info->sechdrs[info->index.str].sh_offset; | |
3251 | break; | |
3264d3f9 | 3252 | } |
3264d3f9 LT |
3253 | } |
3254 | ||
5fdc7db6 | 3255 | if (info->index.sym == 0) { |
708e0ada JY |
3256 | pr_warn("%s: module has no symbols (stripped?)\n", |
3257 | info->name ?: "(missing .modinfo section or name field)"); | |
5fdc7db6 JY |
3258 | return -ENOEXEC; |
3259 | } | |
3260 | ||
49668688 | 3261 | info->index.mod = find_sec(info, ".gnu.linkonce.this_module"); |
3264d3f9 | 3262 | if (!info->index.mod) { |
3e2e857f | 3263 | pr_warn("%s: No module found in object\n", |
708e0ada | 3264 | info->name ?: "(missing .modinfo section or name field)"); |
81a0abd9 | 3265 | return -ENOEXEC; |
3264d3f9 LT |
3266 | } |
3267 | /* This is temporary: point mod into copy of data. */ | |
5fdc7db6 | 3268 | info->mod = (void *)info->hdr + info->sechdrs[info->index.mod].sh_offset; |
3264d3f9 | 3269 | |
3e2e857f | 3270 | /* |
5fdc7db6 | 3271 | * If we didn't load the .modinfo 'name' field earlier, fall back to |
3e2e857f KC |
3272 | * on-disk struct mod 'name' field. |
3273 | */ | |
3274 | if (!info->name) | |
81a0abd9 | 3275 | info->name = info->mod->name; |
3e2e857f | 3276 | |
5fdc7db6 JY |
3277 | if (flags & MODULE_INIT_IGNORE_MODVERSIONS) |
3278 | info->index.vers = 0; /* Pretend no __versions section! */ | |
3279 | else | |
3280 | info->index.vers = find_sec(info, "__versions"); | |
3264d3f9 | 3281 | |
49668688 | 3282 | info->index.pcpu = find_pcpusec(info); |
3264d3f9 | 3283 | |
81a0abd9 | 3284 | return 0; |
3264d3f9 LT |
3285 | } |
3286 | ||
2f3238ae | 3287 | static int check_modinfo(struct module *mod, struct load_info *info, int flags) |
40dd2560 | 3288 | { |
49668688 | 3289 | const char *modmagic = get_modinfo(info, "vermagic"); |
40dd2560 RR |
3290 | int err; |
3291 | ||
2f3238ae RR |
3292 | if (flags & MODULE_INIT_IGNORE_VERMAGIC) |
3293 | modmagic = NULL; | |
3294 | ||
40dd2560 RR |
3295 | /* This is allowed: modprobe --force will invalidate it. */ |
3296 | if (!modmagic) { | |
3297 | err = try_to_force_load(mod, "bad vermagic"); | |
3298 | if (err) | |
3299 | return err; | |
49668688 | 3300 | } else if (!same_magic(modmagic, vermagic, info->index.vers)) { |
bddb12b3 | 3301 | pr_err("%s: version magic '%s' should be '%s'\n", |
3e2e857f | 3302 | info->name, modmagic, vermagic); |
40dd2560 RR |
3303 | return -ENOEXEC; |
3304 | } | |
3305 | ||
3205c36c LP |
3306 | if (!get_modinfo(info, "intree")) { |
3307 | if (!test_taint(TAINT_OOT_MODULE)) | |
3308 | pr_warn("%s: loading out-of-tree module taints kernel.\n", | |
3309 | mod->name); | |
373d4d09 | 3310 | add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK); |
3205c36c | 3311 | } |
2449b8ba | 3312 | |
caf7501a AK |
3313 | check_modinfo_retpoline(mod, info); |
3314 | ||
49668688 | 3315 | if (get_modinfo(info, "staging")) { |
373d4d09 | 3316 | add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK); |
bddb12b3 AM |
3317 | pr_warn("%s: module is from the staging directory, the quality " |
3318 | "is unknown, you have been warned.\n", mod->name); | |
40dd2560 | 3319 | } |
22e268eb | 3320 | |
2992ef29 | 3321 | err = check_modinfo_livepatch(mod, info); |
1ce15ef4 JY |
3322 | if (err) |
3323 | return err; | |
3324 | ||
22e268eb | 3325 | /* Set up license info based on the info section */ |
49668688 | 3326 | set_license(mod, get_modinfo(info, "license")); |
22e268eb | 3327 | |
40dd2560 RR |
3328 | return 0; |
3329 | } | |
3330 | ||
eb3057df | 3331 | static int find_module_sections(struct module *mod, struct load_info *info) |
f91a13bb | 3332 | { |
49668688 | 3333 | mod->kp = section_objs(info, "__param", |
f91a13bb | 3334 | sizeof(*mod->kp), &mod->num_kp); |
49668688 | 3335 | mod->syms = section_objs(info, "__ksymtab", |
f91a13bb | 3336 | sizeof(*mod->syms), &mod->num_syms); |
49668688 RR |
3337 | mod->crcs = section_addr(info, "__kcrctab"); |
3338 | mod->gpl_syms = section_objs(info, "__ksymtab_gpl", | |
f91a13bb LT |
3339 | sizeof(*mod->gpl_syms), |
3340 | &mod->num_gpl_syms); | |
49668688 RR |
3341 | mod->gpl_crcs = section_addr(info, "__kcrctab_gpl"); |
3342 | mod->gpl_future_syms = section_objs(info, | |
f91a13bb LT |
3343 | "__ksymtab_gpl_future", |
3344 | sizeof(*mod->gpl_future_syms), | |
3345 | &mod->num_gpl_future_syms); | |
49668688 | 3346 | mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future"); |
f91a13bb LT |
3347 | |
3348 | #ifdef CONFIG_UNUSED_SYMBOLS | |
49668688 | 3349 | mod->unused_syms = section_objs(info, "__ksymtab_unused", |
f91a13bb LT |
3350 | sizeof(*mod->unused_syms), |
3351 | &mod->num_unused_syms); | |
49668688 RR |
3352 | mod->unused_crcs = section_addr(info, "__kcrctab_unused"); |
3353 | mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl", | |
f91a13bb LT |
3354 | sizeof(*mod->unused_gpl_syms), |
3355 | &mod->num_unused_gpl_syms); | |
49668688 | 3356 | mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl"); |
f91a13bb LT |
3357 | #endif |
3358 | #ifdef CONFIG_CONSTRUCTORS | |
49668688 | 3359 | mod->ctors = section_objs(info, ".ctors", |
f91a13bb | 3360 | sizeof(*mod->ctors), &mod->num_ctors); |
eb3057df FH |
3361 | if (!mod->ctors) |
3362 | mod->ctors = section_objs(info, ".init_array", | |
3363 | sizeof(*mod->ctors), &mod->num_ctors); | |
3364 | else if (find_sec(info, ".init_array")) { | |
3365 | /* | |
3366 | * This shouldn't happen with same compiler and binutils | |
3367 | * building all parts of the module. | |
3368 | */ | |
6da0b565 | 3369 | pr_warn("%s: has both .ctors and .init_array.\n", |
eb3057df FH |
3370 | mod->name); |
3371 | return -EINVAL; | |
3372 | } | |
f91a13bb LT |
3373 | #endif |
3374 | ||
66e9b071 TG |
3375 | mod->noinstr_text_start = section_objs(info, ".noinstr.text", 1, |
3376 | &mod->noinstr_text_size); | |
3377 | ||
f91a13bb | 3378 | #ifdef CONFIG_TRACEPOINTS |
65498646 MD |
3379 | mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs", |
3380 | sizeof(*mod->tracepoints_ptrs), | |
3381 | &mod->num_tracepoints); | |
f91a13bb | 3382 | #endif |
fe15b50c PM |
3383 | #ifdef CONFIG_TREE_SRCU |
3384 | mod->srcu_struct_ptrs = section_objs(info, "___srcu_struct_ptrs", | |
3385 | sizeof(*mod->srcu_struct_ptrs), | |
3386 | &mod->num_srcu_structs); | |
3387 | #endif | |
a38d1107 MM |
3388 | #ifdef CONFIG_BPF_EVENTS |
3389 | mod->bpf_raw_events = section_objs(info, "__bpf_raw_tp_map", | |
3390 | sizeof(*mod->bpf_raw_events), | |
3391 | &mod->num_bpf_raw_events); | |
3392 | #endif | |
36e68442 AN |
3393 | #ifdef CONFIG_DEBUG_INFO_BTF_MODULES |
3394 | mod->btf_data = any_section_objs(info, ".BTF", 1, &mod->btf_data_size); | |
3395 | #endif | |
e9666d10 | 3396 | #ifdef CONFIG_JUMP_LABEL |
bf5438fc JB |
3397 | mod->jump_entries = section_objs(info, "__jump_table", |
3398 | sizeof(*mod->jump_entries), | |
3399 | &mod->num_jump_entries); | |
3400 | #endif | |
f91a13bb | 3401 | #ifdef CONFIG_EVENT_TRACING |
49668688 | 3402 | mod->trace_events = section_objs(info, "_ftrace_events", |
f91a13bb LT |
3403 | sizeof(*mod->trace_events), |
3404 | &mod->num_trace_events); | |
99be647c JL |
3405 | mod->trace_evals = section_objs(info, "_ftrace_eval_map", |
3406 | sizeof(*mod->trace_evals), | |
3407 | &mod->num_trace_evals); | |
f91a13bb | 3408 | #endif |
13b9b6e7 SR |
3409 | #ifdef CONFIG_TRACING |
3410 | mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt", | |
3411 | sizeof(*mod->trace_bprintk_fmt_start), | |
3412 | &mod->num_trace_bprintk_fmt); | |
13b9b6e7 | 3413 | #endif |
f91a13bb LT |
3414 | #ifdef CONFIG_FTRACE_MCOUNT_RECORD |
3415 | /* sechdrs[0].sh_size is always zero */ | |
a1326b17 | 3416 | mod->ftrace_callsites = section_objs(info, FTRACE_CALLSITE_SECTION, |
f91a13bb LT |
3417 | sizeof(*mod->ftrace_callsites), |
3418 | &mod->num_ftrace_callsites); | |
3419 | #endif | |
540adea3 MH |
3420 | #ifdef CONFIG_FUNCTION_ERROR_INJECTION |
3421 | mod->ei_funcs = section_objs(info, "_error_injection_whitelist", | |
3422 | sizeof(*mod->ei_funcs), | |
3423 | &mod->num_ei_funcs); | |
1e6769b0 MH |
3424 | #endif |
3425 | #ifdef CONFIG_KPROBES | |
3426 | mod->kprobes_text_start = section_objs(info, ".kprobes.text", 1, | |
3427 | &mod->kprobes_text_size); | |
16db6264 MH |
3428 | mod->kprobe_blacklist = section_objs(info, "_kprobe_blacklist", |
3429 | sizeof(unsigned long), | |
3430 | &mod->num_kprobe_blacklist); | |
9183c3f9 JP |
3431 | #endif |
3432 | #ifdef CONFIG_HAVE_STATIC_CALL_INLINE | |
3433 | mod->static_call_sites = section_objs(info, ".static_call_sites", | |
3434 | sizeof(*mod->static_call_sites), | |
3435 | &mod->num_static_call_sites); | |
92ace999 | 3436 | #endif |
811d66a0 RR |
3437 | mod->extable = section_objs(info, "__ex_table", |
3438 | sizeof(*mod->extable), &mod->num_exentries); | |
3439 | ||
49668688 | 3440 | if (section_addr(info, "__obsparm")) |
bddb12b3 | 3441 | pr_warn("%s: Ignoring obsolete parameters\n", mod->name); |
811d66a0 | 3442 | |
e5ebffe1 | 3443 | info->debug = section_objs(info, "__dyndbg", |
811d66a0 | 3444 | sizeof(*info->debug), &info->num_debug); |
eb3057df FH |
3445 | |
3446 | return 0; | |
f91a13bb LT |
3447 | } |
3448 | ||
49668688 | 3449 | static int move_module(struct module *mod, struct load_info *info) |
65b8a9b4 LT |
3450 | { |
3451 | int i; | |
3452 | void *ptr; | |
3453 | ||
3454 | /* Do the allocs. */ | |
7523e4dc | 3455 | ptr = module_alloc(mod->core_layout.size); |
65b8a9b4 LT |
3456 | /* |
3457 | * The pointer to this block is stored in the module structure | |
3458 | * which is inside the block. Just mark it as not being a | |
3459 | * leak. | |
3460 | */ | |
3461 | kmemleak_not_leak(ptr); | |
3462 | if (!ptr) | |
d913188c | 3463 | return -ENOMEM; |
65b8a9b4 | 3464 | |
7523e4dc RR |
3465 | memset(ptr, 0, mod->core_layout.size); |
3466 | mod->core_layout.base = ptr; | |
65b8a9b4 | 3467 | |
7523e4dc RR |
3468 | if (mod->init_layout.size) { |
3469 | ptr = module_alloc(mod->init_layout.size); | |
82fab442 RR |
3470 | /* |
3471 | * The pointer to this block is stored in the module structure | |
3472 | * which is inside the block. This block doesn't need to be | |
3473 | * scanned as it contains data and code that will be freed | |
3474 | * after the module is initialized. | |
3475 | */ | |
3476 | kmemleak_ignore(ptr); | |
3477 | if (!ptr) { | |
7523e4dc | 3478 | module_memfree(mod->core_layout.base); |
82fab442 RR |
3479 | return -ENOMEM; |
3480 | } | |
7523e4dc RR |
3481 | memset(ptr, 0, mod->init_layout.size); |
3482 | mod->init_layout.base = ptr; | |
82fab442 | 3483 | } else |
7523e4dc | 3484 | mod->init_layout.base = NULL; |
65b8a9b4 LT |
3485 | |
3486 | /* Transfer each section which specifies SHF_ALLOC */ | |
5e124169 | 3487 | pr_debug("final section addresses:\n"); |
49668688 | 3488 | for (i = 0; i < info->hdr->e_shnum; i++) { |
65b8a9b4 | 3489 | void *dest; |
49668688 | 3490 | Elf_Shdr *shdr = &info->sechdrs[i]; |
65b8a9b4 | 3491 | |
49668688 | 3492 | if (!(shdr->sh_flags & SHF_ALLOC)) |
65b8a9b4 LT |
3493 | continue; |
3494 | ||
49668688 | 3495 | if (shdr->sh_entsize & INIT_OFFSET_MASK) |
7523e4dc | 3496 | dest = mod->init_layout.base |
49668688 | 3497 | + (shdr->sh_entsize & ~INIT_OFFSET_MASK); |
65b8a9b4 | 3498 | else |
7523e4dc | 3499 | dest = mod->core_layout.base + shdr->sh_entsize; |
65b8a9b4 | 3500 | |
49668688 RR |
3501 | if (shdr->sh_type != SHT_NOBITS) |
3502 | memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size); | |
65b8a9b4 | 3503 | /* Update sh_addr to point to copy in image. */ |
49668688 | 3504 | shdr->sh_addr = (unsigned long)dest; |
5e124169 JC |
3505 | pr_debug("\t0x%lx %s\n", |
3506 | (long)shdr->sh_addr, info->secstrings + shdr->sh_name); | |
65b8a9b4 | 3507 | } |
d913188c RR |
3508 | |
3509 | return 0; | |
65b8a9b4 LT |
3510 | } |
3511 | ||
49668688 | 3512 | static int check_module_license_and_versions(struct module *mod) |
22e268eb | 3513 | { |
3205c36c LP |
3514 | int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE); |
3515 | ||
22e268eb RR |
3516 | /* |
3517 | * ndiswrapper is under GPL by itself, but loads proprietary modules. | |
3518 | * Don't use add_taint_module(), as it would prevent ndiswrapper from | |
3519 | * using GPL-only symbols it needs. | |
3520 | */ | |
3521 | if (strcmp(mod->name, "ndiswrapper") == 0) | |
373d4d09 | 3522 | add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE); |
22e268eb RR |
3523 | |
3524 | /* driverloader was caught wrongly pretending to be under GPL */ | |
3525 | if (strcmp(mod->name, "driverloader") == 0) | |
373d4d09 RR |
3526 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
3527 | LOCKDEP_NOW_UNRELIABLE); | |
22e268eb | 3528 | |
c99af375 MG |
3529 | /* lve claims to be GPL but upstream won't provide source */ |
3530 | if (strcmp(mod->name, "lve") == 0) | |
373d4d09 RR |
3531 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
3532 | LOCKDEP_NOW_UNRELIABLE); | |
c99af375 | 3533 | |
3205c36c LP |
3534 | if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE)) |
3535 | pr_warn("%s: module license taints kernel.\n", mod->name); | |
3536 | ||
22e268eb RR |
3537 | #ifdef CONFIG_MODVERSIONS |
3538 | if ((mod->num_syms && !mod->crcs) | |
3539 | || (mod->num_gpl_syms && !mod->gpl_crcs) | |
3540 | || (mod->num_gpl_future_syms && !mod->gpl_future_crcs) | |
3541 | #ifdef CONFIG_UNUSED_SYMBOLS | |
3542 | || (mod->num_unused_syms && !mod->unused_crcs) | |
3543 | || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs) | |
3544 | #endif | |
3545 | ) { | |
3546 | return try_to_force_load(mod, | |
3547 | "no versions for exported symbols"); | |
3548 | } | |
3549 | #endif | |
3550 | return 0; | |
3551 | } | |
3552 | ||
3553 | static void flush_module_icache(const struct module *mod) | |
3554 | { | |
22e268eb RR |
3555 | /* |
3556 | * Flush the instruction cache, since we've played with text. | |
3557 | * Do it before processing of module parameters, so the module | |
3558 | * can provide parameter accessor functions of its own. | |
3559 | */ | |
7523e4dc RR |
3560 | if (mod->init_layout.base) |
3561 | flush_icache_range((unsigned long)mod->init_layout.base, | |
3562 | (unsigned long)mod->init_layout.base | |
3563 | + mod->init_layout.size); | |
3564 | flush_icache_range((unsigned long)mod->core_layout.base, | |
3565 | (unsigned long)mod->core_layout.base + mod->core_layout.size); | |
22e268eb RR |
3566 | } |
3567 | ||
74e08fcf JB |
3568 | int __weak module_frob_arch_sections(Elf_Ehdr *hdr, |
3569 | Elf_Shdr *sechdrs, | |
3570 | char *secstrings, | |
3571 | struct module *mod) | |
3572 | { | |
3573 | return 0; | |
3574 | } | |
3575 | ||
be7de5f9 PB |
3576 | /* module_blacklist is a comma-separated list of module names */ |
3577 | static char *module_blacklist; | |
96b5b194 | 3578 | static bool blacklisted(const char *module_name) |
be7de5f9 PB |
3579 | { |
3580 | const char *p; | |
3581 | size_t len; | |
3582 | ||
3583 | if (!module_blacklist) | |
3584 | return false; | |
3585 | ||
3586 | for (p = module_blacklist; *p; p += len) { | |
3587 | len = strcspn(p, ","); | |
3588 | if (strlen(module_name) == len && !memcmp(module_name, p, len)) | |
3589 | return true; | |
3590 | if (p[len] == ',') | |
3591 | len++; | |
3592 | } | |
3593 | return false; | |
3594 | } | |
3595 | core_param(module_blacklist, module_blacklist, charp, 0400); | |
3596 | ||
2f3238ae | 3597 | static struct module *layout_and_allocate(struct load_info *info, int flags) |
1da177e4 | 3598 | { |
1da177e4 | 3599 | struct module *mod; |
444d13ff | 3600 | unsigned int ndx; |
d913188c | 3601 | int err; |
3ae91c21 | 3602 | |
81a0abd9 | 3603 | err = check_modinfo(info->mod, info, flags); |
40dd2560 RR |
3604 | if (err) |
3605 | return ERR_PTR(err); | |
1da177e4 | 3606 | |
1da177e4 | 3607 | /* Allow arches to frob section contents and sizes. */ |
49668688 | 3608 | err = module_frob_arch_sections(info->hdr, info->sechdrs, |
81a0abd9 | 3609 | info->secstrings, info->mod); |
1da177e4 | 3610 | if (err < 0) |
8d8022e8 | 3611 | return ERR_PTR(err); |
1da177e4 | 3612 | |
5c3a7db0 PZ |
3613 | err = module_enforce_rwx_sections(info->hdr, info->sechdrs, |
3614 | info->secstrings, info->mod); | |
3615 | if (err < 0) | |
3616 | return ERR_PTR(err); | |
3617 | ||
8d8022e8 RR |
3618 | /* We will do a special allocation for per-cpu sections later. */ |
3619 | info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
1da177e4 | 3620 | |
444d13ff JY |
3621 | /* |
3622 | * Mark ro_after_init section with SHF_RO_AFTER_INIT so that | |
3623 | * layout_sections() can put it in the right place. | |
3624 | * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set. | |
3625 | */ | |
3626 | ndx = find_sec(info, ".data..ro_after_init"); | |
e872267b AB |
3627 | if (ndx) |
3628 | info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT; | |
3629 | /* | |
3630 | * Mark the __jump_table section as ro_after_init as well: these data | |
3631 | * structures are never modified, with the exception of entries that | |
3632 | * refer to code in the __init section, which are annotated as such | |
3633 | * at module load time. | |
3634 | */ | |
3635 | ndx = find_sec(info, "__jump_table"); | |
444d13ff JY |
3636 | if (ndx) |
3637 | info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT; | |
3638 | ||
24b9f0d2 SS |
3639 | /* |
3640 | * Determine total sizes, and put offsets in sh_entsize. For now | |
3641 | * this is done generically; there doesn't appear to be any | |
3642 | * special cases for the architectures. | |
3643 | */ | |
81a0abd9 JY |
3644 | layout_sections(info->mod, info); |
3645 | layout_symtab(info->mod, info); | |
1da177e4 | 3646 | |
65b8a9b4 | 3647 | /* Allocate and move to the final place */ |
81a0abd9 | 3648 | err = move_module(info->mod, info); |
d913188c | 3649 | if (err) |
8d8022e8 | 3650 | return ERR_PTR(err); |
d913188c RR |
3651 | |
3652 | /* Module has been copied to its final place now: return it. */ | |
3653 | mod = (void *)info->sechdrs[info->index.mod].sh_addr; | |
49668688 | 3654 | kmemleak_load_module(mod, info); |
d913188c | 3655 | return mod; |
d913188c RR |
3656 | } |
3657 | ||
3658 | /* mod is no longer valid after this! */ | |
3659 | static void module_deallocate(struct module *mod, struct load_info *info) | |
3660 | { | |
d913188c | 3661 | percpu_modfree(mod); |
d453cded | 3662 | module_arch_freeing_init(mod); |
7523e4dc RR |
3663 | module_memfree(mod->init_layout.base); |
3664 | module_memfree(mod->core_layout.base); | |
d913188c RR |
3665 | } |
3666 | ||
74e08fcf JB |
3667 | int __weak module_finalize(const Elf_Ehdr *hdr, |
3668 | const Elf_Shdr *sechdrs, | |
3669 | struct module *me) | |
3670 | { | |
3671 | return 0; | |
3672 | } | |
3673 | ||
811d66a0 RR |
3674 | static int post_relocation(struct module *mod, const struct load_info *info) |
3675 | { | |
51f3d0f4 | 3676 | /* Sort exception table now relocations are done. */ |
811d66a0 RR |
3677 | sort_extable(mod->extable, mod->extable + mod->num_exentries); |
3678 | ||
3679 | /* Copy relocated percpu area over. */ | |
3680 | percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr, | |
3681 | info->sechdrs[info->index.pcpu].sh_size); | |
3682 | ||
51f3d0f4 | 3683 | /* Setup kallsyms-specific fields. */ |
811d66a0 RR |
3684 | add_kallsyms(mod, info); |
3685 | ||
3686 | /* Arch-specific module finalizing. */ | |
3687 | return module_finalize(info->hdr, info->sechdrs, mod); | |
3688 | } | |
3689 | ||
9bb9c3be RR |
3690 | /* Is this module of this name done loading? No locks held. */ |
3691 | static bool finished_loading(const char *name) | |
3692 | { | |
3693 | struct module *mod; | |
3694 | bool ret; | |
3695 | ||
9cc019b8 PZ |
3696 | /* |
3697 | * The module_mutex should not be a heavily contended lock; | |
3698 | * if we get the occasional sleep here, we'll go an extra iteration | |
3699 | * in the wait_event_interruptible(), which is harmless. | |
3700 | */ | |
3701 | sched_annotate_sleep(); | |
9bb9c3be | 3702 | mutex_lock(&module_mutex); |
4f6de4d5 | 3703 | mod = find_module_all(name, strlen(name), true); |
6e6de3de | 3704 | ret = !mod || mod->state == MODULE_STATE_LIVE; |
9bb9c3be RR |
3705 | mutex_unlock(&module_mutex); |
3706 | ||
3707 | return ret; | |
3708 | } | |
3709 | ||
34e1169d KC |
3710 | /* Call module constructors. */ |
3711 | static void do_mod_ctors(struct module *mod) | |
3712 | { | |
3713 | #ifdef CONFIG_CONSTRUCTORS | |
3714 | unsigned long i; | |
3715 | ||
3716 | for (i = 0; i < mod->num_ctors; i++) | |
3717 | mod->ctors[i](); | |
3718 | #endif | |
3719 | } | |
3720 | ||
c7496379 RR |
3721 | /* For freeing module_init on success, in case kallsyms traversing */ |
3722 | struct mod_initfree { | |
1a7b7d92 | 3723 | struct llist_node node; |
c7496379 RR |
3724 | void *module_init; |
3725 | }; | |
3726 | ||
1a7b7d92 | 3727 | static void do_free_init(struct work_struct *w) |
c7496379 | 3728 | { |
1a7b7d92 RE |
3729 | struct llist_node *pos, *n, *list; |
3730 | struct mod_initfree *initfree; | |
3731 | ||
3732 | list = llist_del_all(&init_free_list); | |
3733 | ||
3734 | synchronize_rcu(); | |
3735 | ||
3736 | llist_for_each_safe(pos, n, list) { | |
3737 | initfree = container_of(pos, struct mod_initfree, node); | |
3738 | module_memfree(initfree->module_init); | |
3739 | kfree(initfree); | |
3740 | } | |
c7496379 RR |
3741 | } |
3742 | ||
be02a186 JK |
3743 | /* |
3744 | * This is where the real work happens. | |
3745 | * | |
3746 | * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb | |
3747 | * helper command 'lx-symbols'. | |
3748 | */ | |
3749 | static noinline int do_init_module(struct module *mod) | |
34e1169d KC |
3750 | { |
3751 | int ret = 0; | |
c7496379 RR |
3752 | struct mod_initfree *freeinit; |
3753 | ||
3754 | freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL); | |
3755 | if (!freeinit) { | |
3756 | ret = -ENOMEM; | |
3757 | goto fail; | |
3758 | } | |
7523e4dc | 3759 | freeinit->module_init = mod->init_layout.base; |
34e1169d | 3760 | |
774a1221 TH |
3761 | /* |
3762 | * We want to find out whether @mod uses async during init. Clear | |
3763 | * PF_USED_ASYNC. async_schedule*() will set it. | |
3764 | */ | |
3765 | current->flags &= ~PF_USED_ASYNC; | |
3766 | ||
34e1169d KC |
3767 | do_mod_ctors(mod); |
3768 | /* Start the module */ | |
3769 | if (mod->init != NULL) | |
3770 | ret = do_one_initcall(mod->init); | |
3771 | if (ret < 0) { | |
c7496379 | 3772 | goto fail_free_freeinit; |
34e1169d KC |
3773 | } |
3774 | if (ret > 0) { | |
bddb12b3 AM |
3775 | pr_warn("%s: '%s'->init suspiciously returned %d, it should " |
3776 | "follow 0/-E convention\n" | |
3777 | "%s: loading module anyway...\n", | |
3778 | __func__, mod->name, ret, __func__); | |
34e1169d KC |
3779 | dump_stack(); |
3780 | } | |
3781 | ||
3782 | /* Now it's a first class citizen! */ | |
3783 | mod->state = MODULE_STATE_LIVE; | |
3784 | blocking_notifier_call_chain(&module_notify_list, | |
3785 | MODULE_STATE_LIVE, mod); | |
3786 | ||
38dc717e JY |
3787 | /* Delay uevent until module has finished its init routine */ |
3788 | kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD); | |
3789 | ||
774a1221 TH |
3790 | /* |
3791 | * We need to finish all async code before the module init sequence | |
3792 | * is done. This has potential to deadlock. For example, a newly | |
3793 | * detected block device can trigger request_module() of the | |
3794 | * default iosched from async probing task. Once userland helper | |
3795 | * reaches here, async_synchronize_full() will wait on the async | |
3796 | * task waiting on request_module() and deadlock. | |
3797 | * | |
3798 | * This deadlock is avoided by perfomring async_synchronize_full() | |
3799 | * iff module init queued any async jobs. This isn't a full | |
3800 | * solution as it will deadlock the same if module loading from | |
3801 | * async jobs nests more than once; however, due to the various | |
3802 | * constraints, this hack seems to be the best option for now. | |
3803 | * Please refer to the following thread for details. | |
3804 | * | |
3805 | * http://thread.gmane.org/gmane.linux.kernel/1420814 | |
3806 | */ | |
f2411da7 | 3807 | if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC)) |
774a1221 | 3808 | async_synchronize_full(); |
34e1169d | 3809 | |
aba4b5c2 | 3810 | ftrace_free_mem(mod, mod->init_layout.base, mod->init_layout.base + |
3e234289 | 3811 | mod->init_layout.size); |
34e1169d KC |
3812 | mutex_lock(&module_mutex); |
3813 | /* Drop initial reference. */ | |
3814 | module_put(mod); | |
3815 | trim_init_extable(mod); | |
3816 | #ifdef CONFIG_KALLSYMS | |
8244062e RR |
3817 | /* Switch to core kallsyms now init is done: kallsyms may be walking! */ |
3818 | rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms); | |
34e1169d | 3819 | #endif |
444d13ff | 3820 | module_enable_ro(mod, true); |
93c2e105 | 3821 | mod_tree_remove_init(mod); |
d453cded | 3822 | module_arch_freeing_init(mod); |
7523e4dc RR |
3823 | mod->init_layout.base = NULL; |
3824 | mod->init_layout.size = 0; | |
3825 | mod->init_layout.ro_size = 0; | |
444d13ff | 3826 | mod->init_layout.ro_after_init_size = 0; |
7523e4dc | 3827 | mod->init_layout.text_size = 0; |
607c543f AN |
3828 | #ifdef CONFIG_DEBUG_INFO_BTF_MODULES |
3829 | /* .BTF is not SHF_ALLOC and will get removed, so sanitize pointer */ | |
3830 | mod->btf_data = NULL; | |
607c543f | 3831 | #endif |
c7496379 RR |
3832 | /* |
3833 | * We want to free module_init, but be aware that kallsyms may be | |
0be964be | 3834 | * walking this with preempt disabled. In all the failure paths, we |
cb2f5536 | 3835 | * call synchronize_rcu(), but we don't want to slow down the success |
1a7b7d92 RE |
3836 | * path. module_memfree() cannot be called in an interrupt, so do the |
3837 | * work and call synchronize_rcu() in a work queue. | |
3838 | * | |
ae646f0b JH |
3839 | * Note that module_alloc() on most architectures creates W+X page |
3840 | * mappings which won't be cleaned up until do_free_init() runs. Any | |
3841 | * code such as mark_rodata_ro() which depends on those mappings to | |
3842 | * be cleaned up needs to sync with the queued work - ie | |
cb2f5536 | 3843 | * rcu_barrier() |
c7496379 | 3844 | */ |
1a7b7d92 RE |
3845 | if (llist_add(&freeinit->node, &init_free_list)) |
3846 | schedule_work(&init_free_wq); | |
3847 | ||
34e1169d KC |
3848 | mutex_unlock(&module_mutex); |
3849 | wake_up_all(&module_wq); | |
3850 | ||
3851 | return 0; | |
c7496379 RR |
3852 | |
3853 | fail_free_freeinit: | |
3854 | kfree(freeinit); | |
3855 | fail: | |
3856 | /* Try to protect us from buggy refcounters. */ | |
3857 | mod->state = MODULE_STATE_GOING; | |
cb2f5536 | 3858 | synchronize_rcu(); |
c7496379 RR |
3859 | module_put(mod); |
3860 | blocking_notifier_call_chain(&module_notify_list, | |
3861 | MODULE_STATE_GOING, mod); | |
7e545d6e | 3862 | klp_module_going(mod); |
7dcd182b | 3863 | ftrace_release_mod(mod); |
c7496379 RR |
3864 | free_module(mod); |
3865 | wake_up_all(&module_wq); | |
3866 | return ret; | |
34e1169d KC |
3867 | } |
3868 | ||
3869 | static int may_init_module(void) | |
3870 | { | |
3871 | if (!capable(CAP_SYS_MODULE) || modules_disabled) | |
3872 | return -EPERM; | |
3873 | ||
3874 | return 0; | |
3875 | } | |
3876 | ||
a3535c7e RR |
3877 | /* |
3878 | * We try to place it in the list now to make sure it's unique before | |
3879 | * we dedicate too many resources. In particular, temporary percpu | |
3880 | * memory exhaustion. | |
3881 | */ | |
3882 | static int add_unformed_module(struct module *mod) | |
3883 | { | |
3884 | int err; | |
3885 | struct module *old; | |
3886 | ||
3887 | mod->state = MODULE_STATE_UNFORMED; | |
3888 | ||
3889 | again: | |
3890 | mutex_lock(&module_mutex); | |
4f6de4d5 MK |
3891 | old = find_module_all(mod->name, strlen(mod->name), true); |
3892 | if (old != NULL) { | |
6e6de3de | 3893 | if (old->state != MODULE_STATE_LIVE) { |
a3535c7e RR |
3894 | /* Wait in case it fails to load. */ |
3895 | mutex_unlock(&module_mutex); | |
9cc019b8 PZ |
3896 | err = wait_event_interruptible(module_wq, |
3897 | finished_loading(mod->name)); | |
a3535c7e RR |
3898 | if (err) |
3899 | goto out_unlocked; | |
3900 | goto again; | |
3901 | } | |
3902 | err = -EEXIST; | |
3903 | goto out; | |
3904 | } | |
4f666546 | 3905 | mod_update_bounds(mod); |
a3535c7e | 3906 | list_add_rcu(&mod->list, &modules); |
93c2e105 | 3907 | mod_tree_insert(mod); |
a3535c7e RR |
3908 | err = 0; |
3909 | ||
3910 | out: | |
3911 | mutex_unlock(&module_mutex); | |
3912 | out_unlocked: | |
3913 | return err; | |
3914 | } | |
3915 | ||
3916 | static int complete_formation(struct module *mod, struct load_info *info) | |
3917 | { | |
3918 | int err; | |
3919 | ||
3920 | mutex_lock(&module_mutex); | |
3921 | ||
3922 | /* Find duplicate symbols (must be called under lock). */ | |
2d25bc55 | 3923 | err = verify_exported_symbols(mod); |
a3535c7e RR |
3924 | if (err < 0) |
3925 | goto out; | |
3926 | ||
3927 | /* This relies on module_mutex for list integrity. */ | |
3928 | module_bug_finalize(info->hdr, info->sechdrs, mod); | |
3929 | ||
444d13ff | 3930 | module_enable_ro(mod, false); |
85c898db | 3931 | module_enable_nx(mod); |
af742623 | 3932 | module_enable_x(mod); |
4982223e | 3933 | |
24b9f0d2 SS |
3934 | /* |
3935 | * Mark state as coming so strong_try_module_get() ignores us, | |
3936 | * but kallsyms etc. can see us. | |
3937 | */ | |
a3535c7e | 3938 | mod->state = MODULE_STATE_COMING; |
4982223e RR |
3939 | mutex_unlock(&module_mutex); |
3940 | ||
4982223e | 3941 | return 0; |
a3535c7e RR |
3942 | |
3943 | out: | |
3944 | mutex_unlock(&module_mutex); | |
3945 | return err; | |
3946 | } | |
3947 | ||
4c973d16 JY |
3948 | static int prepare_coming_module(struct module *mod) |
3949 | { | |
7e545d6e JY |
3950 | int err; |
3951 | ||
4c973d16 | 3952 | ftrace_module_enable(mod); |
7e545d6e JY |
3953 | err = klp_module_coming(mod); |
3954 | if (err) | |
3955 | return err; | |
3956 | ||
59cc8e0a PZ |
3957 | err = blocking_notifier_call_chain_robust(&module_notify_list, |
3958 | MODULE_STATE_COMING, MODULE_STATE_GOING, mod); | |
3959 | err = notifier_to_errno(err); | |
3960 | if (err) | |
3961 | klp_module_going(mod); | |
3962 | ||
3963 | return err; | |
4c973d16 JY |
3964 | } |
3965 | ||
ecc86170 LR |
3966 | static int unknown_module_param_cb(char *param, char *val, const char *modname, |
3967 | void *arg) | |
54041d8a | 3968 | { |
f2411da7 LR |
3969 | struct module *mod = arg; |
3970 | int ret; | |
3971 | ||
3972 | if (strcmp(param, "async_probe") == 0) { | |
3973 | mod->async_probe_requested = true; | |
3974 | return 0; | |
3975 | } | |
3976 | ||
6da0b565 | 3977 | /* Check for magic 'dyndbg' arg */ |
f2411da7 | 3978 | ret = ddebug_dyndbg_module_param_cb(param, val, modname); |
bddb12b3 AM |
3979 | if (ret != 0) |
3980 | pr_warn("%s: unknown parameter '%s' ignored\n", modname, param); | |
54041d8a RR |
3981 | return 0; |
3982 | } | |
3983 | ||
24b9f0d2 SS |
3984 | /* |
3985 | * Allocate and load the module: note that size of section 0 is always | |
3986 | * zero, and we rely on this for optional sections. | |
3987 | */ | |
2f3238ae RR |
3988 | static int load_module(struct load_info *info, const char __user *uargs, |
3989 | int flags) | |
d913188c | 3990 | { |
a3535c7e | 3991 | struct module *mod; |
5fdc7db6 | 3992 | long err = 0; |
51e158c1 | 3993 | char *after_dashes; |
d913188c | 3994 | |
b484304a FL |
3995 | /* |
3996 | * Do the signature check (if any) first. All that | |
3997 | * the signature check needs is info->len, it does | |
3998 | * not need any of the section info. That can be | |
3999 | * set up later. This will minimize the chances | |
4000 | * of a corrupt module causing problems before | |
4001 | * we even get to the signature check. | |
4002 | * | |
4003 | * The check will also adjust info->len by stripping | |
4004 | * off the sig length at the end of the module, making | |
4005 | * checks against info->len more correct. | |
4006 | */ | |
4007 | err = module_sig_check(info, flags); | |
4008 | if (err) | |
4009 | goto free_copy; | |
4010 | ||
4011 | /* | |
4012 | * Do basic sanity checks against the ELF header and | |
4013 | * sections. | |
4014 | */ | |
4015 | err = elf_validity_check(info); | |
14721add | 4016 | if (err) { |
b484304a | 4017 | pr_err("Module has invalid ELF structures\n"); |
5fdc7db6 | 4018 | goto free_copy; |
14721add | 4019 | } |
5fdc7db6 | 4020 | |
b484304a FL |
4021 | /* |
4022 | * Everything checks out, so set up the section info | |
4023 | * in the info structure. | |
4024 | */ | |
5fdc7db6 JY |
4025 | err = setup_load_info(info, flags); |
4026 | if (err) | |
4027 | goto free_copy; | |
4028 | ||
b484304a FL |
4029 | /* |
4030 | * Now that we know we have the correct module name, check | |
4031 | * if it's blacklisted. | |
4032 | */ | |
5fdc7db6 JY |
4033 | if (blacklisted(info->name)) { |
4034 | err = -EPERM; | |
14721add | 4035 | pr_err("Module %s is blacklisted\n", info->name); |
5fdc7db6 JY |
4036 | goto free_copy; |
4037 | } | |
4038 | ||
5fdc7db6 | 4039 | err = rewrite_section_headers(info, flags); |
d913188c | 4040 | if (err) |
34e1169d | 4041 | goto free_copy; |
d913188c | 4042 | |
5fdc7db6 JY |
4043 | /* Check module struct version now, before we try to use module. */ |
4044 | if (!check_modstruct_version(info, info->mod)) { | |
4045 | err = -ENOEXEC; | |
4046 | goto free_copy; | |
4047 | } | |
4048 | ||
d913188c | 4049 | /* Figure out module layout, and allocate all the memory. */ |
2f3238ae | 4050 | mod = layout_and_allocate(info, flags); |
65b8a9b4 LT |
4051 | if (IS_ERR(mod)) { |
4052 | err = PTR_ERR(mod); | |
d913188c | 4053 | goto free_copy; |
1da177e4 | 4054 | } |
1da177e4 | 4055 | |
ca86cad7 RGB |
4056 | audit_log_kern_module(mod->name); |
4057 | ||
a3535c7e RR |
4058 | /* Reserve our place in the list. */ |
4059 | err = add_unformed_module(mod); | |
4060 | if (err) | |
1fb9341a | 4061 | goto free_module; |
1fb9341a | 4062 | |
106a4ee2 | 4063 | #ifdef CONFIG_MODULE_SIG |
34e1169d | 4064 | mod->sig_ok = info->sig_ok; |
64748a2c | 4065 | if (!mod->sig_ok) { |
bddb12b3 | 4066 | pr_notice_once("%s: module verification failed: signature " |
ab92ebbb | 4067 | "and/or required key missing - tainting " |
bddb12b3 | 4068 | "kernel\n", mod->name); |
66cc69e3 | 4069 | add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK); |
64748a2c | 4070 | } |
106a4ee2 RR |
4071 | #endif |
4072 | ||
8d8022e8 | 4073 | /* To avoid stressing percpu allocator, do this once we're unique. */ |
9eb76d77 | 4074 | err = percpu_modalloc(mod, info); |
8d8022e8 RR |
4075 | if (err) |
4076 | goto unlink_mod; | |
4077 | ||
49668688 | 4078 | /* Now module is in final location, initialize linked lists, etc. */ |
9f85a4bb RR |
4079 | err = module_unload_init(mod); |
4080 | if (err) | |
1fb9341a | 4081 | goto unlink_mod; |
1da177e4 | 4082 | |
cf2fde7b | 4083 | init_param_lock(mod); |
b51d23e4 | 4084 | |
24b9f0d2 SS |
4085 | /* |
4086 | * Now we've got everything in the final locations, we can | |
4087 | * find optional sections. | |
4088 | */ | |
eb3057df FH |
4089 | err = find_module_sections(mod, info); |
4090 | if (err) | |
4091 | goto free_unload; | |
9b37ccfc | 4092 | |
49668688 | 4093 | err = check_module_license_and_versions(mod); |
22e268eb RR |
4094 | if (err) |
4095 | goto free_unload; | |
9841d61d | 4096 | |
c988d2b2 | 4097 | /* Set up MODINFO_ATTR fields */ |
34e1169d | 4098 | setup_modinfo(mod, info); |
c988d2b2 | 4099 | |
1da177e4 | 4100 | /* Fix up syms, so that st_value is a pointer to location. */ |
34e1169d | 4101 | err = simplify_symbols(mod, info); |
1da177e4 | 4102 | if (err < 0) |
d913188c | 4103 | goto free_modinfo; |
1da177e4 | 4104 | |
34e1169d | 4105 | err = apply_relocations(mod, info); |
22e268eb | 4106 | if (err < 0) |
d913188c | 4107 | goto free_modinfo; |
1da177e4 | 4108 | |
34e1169d | 4109 | err = post_relocation(mod, info); |
1da177e4 | 4110 | if (err < 0) |
d913188c | 4111 | goto free_modinfo; |
1da177e4 | 4112 | |
22e268eb | 4113 | flush_module_icache(mod); |
378bac82 | 4114 | |
6526c534 RR |
4115 | /* Now copy in args */ |
4116 | mod->args = strndup_user(uargs, ~0UL >> 1); | |
4117 | if (IS_ERR(mod->args)) { | |
4118 | err = PTR_ERR(mod->args); | |
4119 | goto free_arch_cleanup; | |
4120 | } | |
8d3b33f6 | 4121 | |
52796312 | 4122 | dynamic_debug_setup(mod, info->debug, info->num_debug); |
ff49d74a | 4123 | |
a949ae56 SRRH |
4124 | /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */ |
4125 | ftrace_module_init(mod); | |
4126 | ||
a3535c7e RR |
4127 | /* Finally it's fully formed, ready to start executing. */ |
4128 | err = complete_formation(mod, info); | |
4129 | if (err) | |
1fb9341a | 4130 | goto ddebug_cleanup; |
be593f4c | 4131 | |
4c973d16 JY |
4132 | err = prepare_coming_module(mod); |
4133 | if (err) | |
4134 | goto bug_cleanup; | |
4135 | ||
51f3d0f4 | 4136 | /* Module is ready to execute: parsing args may do that. */ |
51e158c1 | 4137 | after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, |
4355efbd | 4138 | -32768, 32767, mod, |
ecc86170 | 4139 | unknown_module_param_cb); |
51e158c1 RR |
4140 | if (IS_ERR(after_dashes)) { |
4141 | err = PTR_ERR(after_dashes); | |
4c973d16 | 4142 | goto coming_cleanup; |
51e158c1 RR |
4143 | } else if (after_dashes) { |
4144 | pr_warn("%s: parameters '%s' after `--' ignored\n", | |
4145 | mod->name, after_dashes); | |
4146 | } | |
1da177e4 | 4147 | |
ca86cad7 | 4148 | /* Link in to sysfs. */ |
34e1169d | 4149 | err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp); |
1da177e4 | 4150 | if (err < 0) |
4c973d16 | 4151 | goto coming_cleanup; |
80a3d1bb | 4152 | |
1ce15ef4 JY |
4153 | if (is_livepatch_module(mod)) { |
4154 | err = copy_module_elf(mod, info); | |
4155 | if (err < 0) | |
4156 | goto sysfs_cleanup; | |
4157 | } | |
4158 | ||
48fd1188 | 4159 | /* Get rid of temporary copy. */ |
34e1169d | 4160 | free_copy(info); |
1da177e4 LT |
4161 | |
4162 | /* Done! */ | |
51f3d0f4 | 4163 | trace_module_load(mod); |
34e1169d KC |
4164 | |
4165 | return do_init_module(mod); | |
1da177e4 | 4166 | |
1ce15ef4 JY |
4167 | sysfs_cleanup: |
4168 | mod_sysfs_teardown(mod); | |
4c973d16 | 4169 | coming_cleanup: |
885a78d4 | 4170 | mod->state = MODULE_STATE_GOING; |
a5544880 | 4171 | destroy_params(mod->kp, mod->num_kp); |
4c973d16 JY |
4172 | blocking_notifier_call_chain(&module_notify_list, |
4173 | MODULE_STATE_GOING, mod); | |
7e545d6e | 4174 | klp_module_going(mod); |
1fb9341a | 4175 | bug_cleanup: |
5e8ed280 | 4176 | mod->state = MODULE_STATE_GOING; |
1fb9341a | 4177 | /* module_bug_cleanup needs module_mutex protection */ |
75676500 | 4178 | mutex_lock(&module_mutex); |
5336377d | 4179 | module_bug_cleanup(mod); |
ee61abb3 | 4180 | mutex_unlock(&module_mutex); |
ff7e0055 | 4181 | |
a3535c7e | 4182 | ddebug_cleanup: |
1323eac7 | 4183 | ftrace_release_mod(mod); |
52796312 | 4184 | dynamic_debug_remove(mod, info->debug); |
cb2f5536 | 4185 | synchronize_rcu(); |
6526c534 RR |
4186 | kfree(mod->args); |
4187 | free_arch_cleanup: | |
1da177e4 | 4188 | module_arch_cleanup(mod); |
d913188c | 4189 | free_modinfo: |
a263f776 | 4190 | free_modinfo(mod); |
22e268eb | 4191 | free_unload: |
1da177e4 | 4192 | module_unload_free(mod); |
1fb9341a RR |
4193 | unlink_mod: |
4194 | mutex_lock(&module_mutex); | |
4195 | /* Unlink carefully: kallsyms could be walking list. */ | |
4196 | list_del_rcu(&mod->list); | |
758556bd | 4197 | mod_tree_remove(mod); |
1fb9341a | 4198 | wake_up_all(&module_wq); |
0be964be | 4199 | /* Wait for RCU-sched synchronizing before releasing mod->list. */ |
cb2f5536 | 4200 | synchronize_rcu(); |
1fb9341a | 4201 | mutex_unlock(&module_mutex); |
d913188c | 4202 | free_module: |
35a9393c | 4203 | /* Free lock-classes; relies on the preceding sync_rcu() */ |
7523e4dc | 4204 | lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size); |
35a9393c | 4205 | |
34e1169d | 4206 | module_deallocate(mod, info); |
d913188c | 4207 | free_copy: |
34e1169d KC |
4208 | free_copy(info); |
4209 | return err; | |
b99b87f7 PO |
4210 | } |
4211 | ||
17da2bd9 HC |
4212 | SYSCALL_DEFINE3(init_module, void __user *, umod, |
4213 | unsigned long, len, const char __user *, uargs) | |
1da177e4 | 4214 | { |
34e1169d KC |
4215 | int err; |
4216 | struct load_info info = { }; | |
1da177e4 | 4217 | |
34e1169d KC |
4218 | err = may_init_module(); |
4219 | if (err) | |
4220 | return err; | |
1da177e4 | 4221 | |
34e1169d KC |
4222 | pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n", |
4223 | umod, len, uargs); | |
1da177e4 | 4224 | |
34e1169d KC |
4225 | err = copy_module_from_user(umod, len, &info); |
4226 | if (err) | |
4227 | return err; | |
1da177e4 | 4228 | |
2f3238ae | 4229 | return load_module(&info, uargs, 0); |
34e1169d | 4230 | } |
94462ad3 | 4231 | |
2f3238ae | 4232 | SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) |
34e1169d | 4233 | { |
34e1169d | 4234 | struct load_info info = { }; |
c307459b | 4235 | void *hdr = NULL; |
a1db7420 | 4236 | int err; |
94462ad3 | 4237 | |
34e1169d KC |
4238 | err = may_init_module(); |
4239 | if (err) | |
4240 | return err; | |
1da177e4 | 4241 | |
2f3238ae | 4242 | pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags); |
6c5db22d | 4243 | |
2f3238ae RR |
4244 | if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS |
4245 | |MODULE_INIT_IGNORE_VERMAGIC)) | |
4246 | return -EINVAL; | |
d6de2c80 | 4247 | |
0fa8e084 | 4248 | err = kernel_read_file_from_fd(fd, 0, &hdr, INT_MAX, NULL, |
a1db7420 | 4249 | READING_MODULE); |
f7a4f689 | 4250 | if (err < 0) |
34e1169d | 4251 | return err; |
a1db7420 | 4252 | info.hdr = hdr; |
f7a4f689 | 4253 | info.len = err; |
1da177e4 | 4254 | |
2f3238ae | 4255 | return load_module(&info, uargs, flags); |
1da177e4 LT |
4256 | } |
4257 | ||
4258 | static inline int within(unsigned long addr, void *start, unsigned long size) | |
4259 | { | |
4260 | return ((void *)addr >= start && (void *)addr < start + size); | |
4261 | } | |
4262 | ||
4263 | #ifdef CONFIG_KALLSYMS | |
4264 | /* | |
4265 | * This ignores the intensely annoying "mapping symbols" found | |
4266 | * in ARM ELF files: $a, $t and $d. | |
4267 | */ | |
4268 | static inline int is_arm_mapping_symbol(const char *str) | |
4269 | { | |
2e3a10a1 RK |
4270 | if (str[0] == '.' && str[1] == 'L') |
4271 | return true; | |
6c34f1f5 | 4272 | return str[0] == '$' && strchr("axtd", str[1]) |
1da177e4 LT |
4273 | && (str[2] == '\0' || str[2] == '.'); |
4274 | } | |
4275 | ||
2d25bc55 | 4276 | static const char *kallsyms_symbol_name(struct mod_kallsyms *kallsyms, unsigned int symnum) |
2e7bac53 | 4277 | { |
8244062e | 4278 | return kallsyms->strtab + kallsyms->symtab[symnum].st_name; |
2e7bac53 RR |
4279 | } |
4280 | ||
2d25bc55 JY |
4281 | /* |
4282 | * Given a module and address, find the corresponding symbol and return its name | |
4283 | * while providing its size and offset if needed. | |
4284 | */ | |
4285 | static const char *find_kallsyms_symbol(struct module *mod, | |
4286 | unsigned long addr, | |
4287 | unsigned long *size, | |
4288 | unsigned long *offset) | |
1da177e4 LT |
4289 | { |
4290 | unsigned int i, best = 0; | |
93d77e7f | 4291 | unsigned long nextval, bestval; |
8244062e | 4292 | struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); |
1da177e4 LT |
4293 | |
4294 | /* At worse, next value is at end of module */ | |
a06f6211 | 4295 | if (within_module_init(addr, mod)) |
7523e4dc | 4296 | nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size; |
22a8bdeb | 4297 | else |
7523e4dc | 4298 | nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size; |
1da177e4 | 4299 | |
93d77e7f VW |
4300 | bestval = kallsyms_symbol_value(&kallsyms->symtab[best]); |
4301 | ||
24b9f0d2 SS |
4302 | /* |
4303 | * Scan for closest preceding symbol, and next symbol. (ELF | |
4304 | * starts real symbols at 1). | |
4305 | */ | |
8244062e | 4306 | for (i = 1; i < kallsyms->num_symtab; i++) { |
93d77e7f VW |
4307 | const Elf_Sym *sym = &kallsyms->symtab[i]; |
4308 | unsigned long thisval = kallsyms_symbol_value(sym); | |
4309 | ||
4310 | if (sym->st_shndx == SHN_UNDEF) | |
1da177e4 LT |
4311 | continue; |
4312 | ||
24b9f0d2 SS |
4313 | /* |
4314 | * We ignore unnamed symbols: they're uninformative | |
4315 | * and inserted at a whim. | |
4316 | */ | |
2d25bc55 JY |
4317 | if (*kallsyms_symbol_name(kallsyms, i) == '\0' |
4318 | || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms, i))) | |
2e7bac53 RR |
4319 | continue; |
4320 | ||
93d77e7f | 4321 | if (thisval <= addr && thisval > bestval) { |
1da177e4 | 4322 | best = i; |
93d77e7f VW |
4323 | bestval = thisval; |
4324 | } | |
4325 | if (thisval > addr && thisval < nextval) | |
4326 | nextval = thisval; | |
1da177e4 LT |
4327 | } |
4328 | ||
4329 | if (!best) | |
4330 | return NULL; | |
4331 | ||
ffb45122 | 4332 | if (size) |
93d77e7f | 4333 | *size = nextval - bestval; |
ffb45122 | 4334 | if (offset) |
93d77e7f | 4335 | *offset = addr - bestval; |
2d25bc55 JY |
4336 | |
4337 | return kallsyms_symbol_name(kallsyms, best); | |
1da177e4 LT |
4338 | } |
4339 | ||
b865ea64 SS |
4340 | void * __weak dereference_module_function_descriptor(struct module *mod, |
4341 | void *ptr) | |
4342 | { | |
4343 | return ptr; | |
4344 | } | |
4345 | ||
24b9f0d2 SS |
4346 | /* |
4347 | * For kallsyms to ask for address resolution. NULL means not found. Careful | |
4348 | * not to lock to avoid deadlock on oopses, simply disable preemption. | |
4349 | */ | |
92dfc9dc | 4350 | const char *module_address_lookup(unsigned long addr, |
6dd06c9f RR |
4351 | unsigned long *size, |
4352 | unsigned long *offset, | |
4353 | char **modname, | |
4354 | char *namebuf) | |
1da177e4 | 4355 | { |
cb2a5205 | 4356 | const char *ret = NULL; |
b7df4d1b | 4357 | struct module *mod; |
1da177e4 | 4358 | |
cb2a5205 | 4359 | preempt_disable(); |
b7df4d1b PZ |
4360 | mod = __module_address(addr); |
4361 | if (mod) { | |
4362 | if (modname) | |
4363 | *modname = mod->name; | |
2d25bc55 JY |
4364 | |
4365 | ret = find_kallsyms_symbol(mod, addr, size, offset); | |
1da177e4 | 4366 | } |
6dd06c9f RR |
4367 | /* Make a copy in here where it's safe */ |
4368 | if (ret) { | |
4369 | strncpy(namebuf, ret, KSYM_NAME_LEN - 1); | |
4370 | ret = namebuf; | |
4371 | } | |
cb2a5205 | 4372 | preempt_enable(); |
b7df4d1b | 4373 | |
92dfc9dc | 4374 | return ret; |
1da177e4 LT |
4375 | } |
4376 | ||
9d65cb4a AD |
4377 | int lookup_module_symbol_name(unsigned long addr, char *symname) |
4378 | { | |
4379 | struct module *mod; | |
4380 | ||
cb2a5205 | 4381 | preempt_disable(); |
d72b3751 | 4382 | list_for_each_entry_rcu(mod, &modules, list) { |
0d21b0e3 RR |
4383 | if (mod->state == MODULE_STATE_UNFORMED) |
4384 | continue; | |
9b20a352 | 4385 | if (within_module(addr, mod)) { |
9d65cb4a AD |
4386 | const char *sym; |
4387 | ||
2d25bc55 | 4388 | sym = find_kallsyms_symbol(mod, addr, NULL, NULL); |
9d65cb4a AD |
4389 | if (!sym) |
4390 | goto out; | |
2d25bc55 | 4391 | |
9281acea | 4392 | strlcpy(symname, sym, KSYM_NAME_LEN); |
cb2a5205 | 4393 | preempt_enable(); |
9d65cb4a AD |
4394 | return 0; |
4395 | } | |
4396 | } | |
4397 | out: | |
cb2a5205 | 4398 | preempt_enable(); |
9d65cb4a AD |
4399 | return -ERANGE; |
4400 | } | |
4401 | ||
a5c43dae AD |
4402 | int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, |
4403 | unsigned long *offset, char *modname, char *name) | |
4404 | { | |
4405 | struct module *mod; | |
4406 | ||
cb2a5205 | 4407 | preempt_disable(); |
d72b3751 | 4408 | list_for_each_entry_rcu(mod, &modules, list) { |
0d21b0e3 RR |
4409 | if (mod->state == MODULE_STATE_UNFORMED) |
4410 | continue; | |
9b20a352 | 4411 | if (within_module(addr, mod)) { |
a5c43dae AD |
4412 | const char *sym; |
4413 | ||
2d25bc55 | 4414 | sym = find_kallsyms_symbol(mod, addr, size, offset); |
a5c43dae AD |
4415 | if (!sym) |
4416 | goto out; | |
4417 | if (modname) | |
9281acea | 4418 | strlcpy(modname, mod->name, MODULE_NAME_LEN); |
a5c43dae | 4419 | if (name) |
9281acea | 4420 | strlcpy(name, sym, KSYM_NAME_LEN); |
cb2a5205 | 4421 | preempt_enable(); |
a5c43dae AD |
4422 | return 0; |
4423 | } | |
4424 | } | |
4425 | out: | |
cb2a5205 | 4426 | preempt_enable(); |
a5c43dae AD |
4427 | return -ERANGE; |
4428 | } | |
4429 | ||
ea07890a AD |
4430 | int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, |
4431 | char *name, char *module_name, int *exported) | |
1da177e4 LT |
4432 | { |
4433 | struct module *mod; | |
4434 | ||
cb2a5205 | 4435 | preempt_disable(); |
d72b3751 | 4436 | list_for_each_entry_rcu(mod, &modules, list) { |
8244062e RR |
4437 | struct mod_kallsyms *kallsyms; |
4438 | ||
0d21b0e3 RR |
4439 | if (mod->state == MODULE_STATE_UNFORMED) |
4440 | continue; | |
8244062e RR |
4441 | kallsyms = rcu_dereference_sched(mod->kallsyms); |
4442 | if (symnum < kallsyms->num_symtab) { | |
93d77e7f VW |
4443 | const Elf_Sym *sym = &kallsyms->symtab[symnum]; |
4444 | ||
4445 | *value = kallsyms_symbol_value(sym); | |
1c7651f4 | 4446 | *type = kallsyms->typetab[symnum]; |
2d25bc55 | 4447 | strlcpy(name, kallsyms_symbol_name(kallsyms, symnum), KSYM_NAME_LEN); |
9281acea | 4448 | strlcpy(module_name, mod->name, MODULE_NAME_LEN); |
ca4787b7 | 4449 | *exported = is_exported(name, *value, mod); |
cb2a5205 | 4450 | preempt_enable(); |
ea07890a | 4451 | return 0; |
1da177e4 | 4452 | } |
8244062e | 4453 | symnum -= kallsyms->num_symtab; |
1da177e4 | 4454 | } |
cb2a5205 | 4455 | preempt_enable(); |
ea07890a | 4456 | return -ERANGE; |
1da177e4 LT |
4457 | } |
4458 | ||
2d25bc55 JY |
4459 | /* Given a module and name of symbol, find and return the symbol's value */ |
4460 | static unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name) | |
1da177e4 LT |
4461 | { |
4462 | unsigned int i; | |
8244062e | 4463 | struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); |
1da177e4 | 4464 | |
93d77e7f VW |
4465 | for (i = 0; i < kallsyms->num_symtab; i++) { |
4466 | const Elf_Sym *sym = &kallsyms->symtab[i]; | |
4467 | ||
2d25bc55 | 4468 | if (strcmp(name, kallsyms_symbol_name(kallsyms, i)) == 0 && |
93d77e7f VW |
4469 | sym->st_shndx != SHN_UNDEF) |
4470 | return kallsyms_symbol_value(sym); | |
4471 | } | |
1da177e4 LT |
4472 | return 0; |
4473 | } | |
4474 | ||
4475 | /* Look for this name: can be of form module:name. */ | |
4476 | unsigned long module_kallsyms_lookup_name(const char *name) | |
4477 | { | |
4478 | struct module *mod; | |
4479 | char *colon; | |
4480 | unsigned long ret = 0; | |
4481 | ||
4482 | /* Don't lock: we're in enough trouble already. */ | |
cb2a5205 | 4483 | preempt_disable(); |
17586188 | 4484 | if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) { |
4f6de4d5 | 4485 | if ((mod = find_module_all(name, colon - name, false)) != NULL) |
2d25bc55 | 4486 | ret = find_kallsyms_symbol_value(mod, colon+1); |
1da177e4 | 4487 | } else { |
0d21b0e3 RR |
4488 | list_for_each_entry_rcu(mod, &modules, list) { |
4489 | if (mod->state == MODULE_STATE_UNFORMED) | |
4490 | continue; | |
2d25bc55 | 4491 | if ((ret = find_kallsyms_symbol_value(mod, name)) != 0) |
1da177e4 | 4492 | break; |
0d21b0e3 | 4493 | } |
1da177e4 | 4494 | } |
cb2a5205 | 4495 | preempt_enable(); |
1da177e4 LT |
4496 | return ret; |
4497 | } | |
75a66614 AK |
4498 | |
4499 | int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, | |
4500 | struct module *, unsigned long), | |
4501 | void *data) | |
4502 | { | |
4503 | struct module *mod; | |
4504 | unsigned int i; | |
4505 | int ret; | |
4506 | ||
0be964be PZ |
4507 | module_assert_mutex(); |
4508 | ||
75a66614 | 4509 | list_for_each_entry(mod, &modules, list) { |
8244062e RR |
4510 | /* We hold module_mutex: no need for rcu_dereference_sched */ |
4511 | struct mod_kallsyms *kallsyms = mod->kallsyms; | |
4512 | ||
0d21b0e3 RR |
4513 | if (mod->state == MODULE_STATE_UNFORMED) |
4514 | continue; | |
8244062e | 4515 | for (i = 0; i < kallsyms->num_symtab; i++) { |
93d77e7f | 4516 | const Elf_Sym *sym = &kallsyms->symtab[i]; |
9f2d1e68 | 4517 | |
93d77e7f | 4518 | if (sym->st_shndx == SHN_UNDEF) |
9f2d1e68 JY |
4519 | continue; |
4520 | ||
2d25bc55 | 4521 | ret = fn(data, kallsyms_symbol_name(kallsyms, i), |
93d77e7f | 4522 | mod, kallsyms_symbol_value(sym)); |
75a66614 AK |
4523 | if (ret != 0) |
4524 | return ret; | |
4525 | } | |
4526 | } | |
4527 | return 0; | |
4528 | } | |
1da177e4 LT |
4529 | #endif /* CONFIG_KALLSYMS */ |
4530 | ||
7fd8329b PM |
4531 | /* Maximum number of characters written by module_flags() */ |
4532 | #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) | |
4533 | ||
4534 | /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */ | |
21aa9280 | 4535 | static char *module_flags(struct module *mod, char *buf) |
fa3ba2e8 FM |
4536 | { |
4537 | int bx = 0; | |
4538 | ||
0d21b0e3 | 4539 | BUG_ON(mod->state == MODULE_STATE_UNFORMED); |
21aa9280 AV |
4540 | if (mod->taints || |
4541 | mod->state == MODULE_STATE_GOING || | |
4542 | mod->state == MODULE_STATE_COMING) { | |
fa3ba2e8 | 4543 | buf[bx++] = '('; |
cca3e707 | 4544 | bx += module_flags_taint(mod, buf + bx); |
21aa9280 AV |
4545 | /* Show a - for module-is-being-unloaded */ |
4546 | if (mod->state == MODULE_STATE_GOING) | |
4547 | buf[bx++] = '-'; | |
4548 | /* Show a + for module-is-being-loaded */ | |
4549 | if (mod->state == MODULE_STATE_COMING) | |
4550 | buf[bx++] = '+'; | |
fa3ba2e8 FM |
4551 | buf[bx++] = ')'; |
4552 | } | |
4553 | buf[bx] = '\0'; | |
4554 | ||
4555 | return buf; | |
4556 | } | |
4557 | ||
3b5d5c6b AD |
4558 | #ifdef CONFIG_PROC_FS |
4559 | /* Called by the /proc file system to return a list of modules. */ | |
4560 | static void *m_start(struct seq_file *m, loff_t *pos) | |
4561 | { | |
4562 | mutex_lock(&module_mutex); | |
4563 | return seq_list_start(&modules, *pos); | |
4564 | } | |
4565 | ||
4566 | static void *m_next(struct seq_file *m, void *p, loff_t *pos) | |
4567 | { | |
4568 | return seq_list_next(p, &modules, pos); | |
4569 | } | |
4570 | ||
4571 | static void m_stop(struct seq_file *m, void *p) | |
4572 | { | |
4573 | mutex_unlock(&module_mutex); | |
4574 | } | |
4575 | ||
1da177e4 LT |
4576 | static int m_show(struct seq_file *m, void *p) |
4577 | { | |
4578 | struct module *mod = list_entry(p, struct module, list); | |
7fd8329b | 4579 | char buf[MODULE_FLAGS_BUF_SIZE]; |
668533dc | 4580 | void *value; |
fa3ba2e8 | 4581 | |
0d21b0e3 RR |
4582 | /* We always ignore unformed modules. */ |
4583 | if (mod->state == MODULE_STATE_UNFORMED) | |
4584 | return 0; | |
4585 | ||
2f0f2a33 | 4586 | seq_printf(m, "%s %u", |
7523e4dc | 4587 | mod->name, mod->init_layout.size + mod->core_layout.size); |
1da177e4 LT |
4588 | print_unload_info(m, mod); |
4589 | ||
4590 | /* Informative for users. */ | |
4591 | seq_printf(m, " %s", | |
6da0b565 IA |
4592 | mod->state == MODULE_STATE_GOING ? "Unloading" : |
4593 | mod->state == MODULE_STATE_COMING ? "Loading" : | |
1da177e4 LT |
4594 | "Live"); |
4595 | /* Used by oprofile and other similar tools. */ | |
668533dc LT |
4596 | value = m->private ? NULL : mod->core_layout.base; |
4597 | seq_printf(m, " 0x%px", value); | |
1da177e4 | 4598 | |
fa3ba2e8 FM |
4599 | /* Taints info */ |
4600 | if (mod->taints) | |
21aa9280 | 4601 | seq_printf(m, " %s", module_flags(mod, buf)); |
fa3ba2e8 | 4602 | |
6da0b565 | 4603 | seq_puts(m, "\n"); |
1da177e4 LT |
4604 | return 0; |
4605 | } | |
4606 | ||
24b9f0d2 SS |
4607 | /* |
4608 | * Format: modulename size refcount deps address | |
4609 | * | |
4610 | * Where refcount is a number or -, and deps is a comma-separated list | |
4611 | * of depends or -. | |
4612 | */ | |
3b5d5c6b | 4613 | static const struct seq_operations modules_op = { |
1da177e4 LT |
4614 | .start = m_start, |
4615 | .next = m_next, | |
4616 | .stop = m_stop, | |
4617 | .show = m_show | |
4618 | }; | |
4619 | ||
516fb7f2 LT |
4620 | /* |
4621 | * This also sets the "private" pointer to non-NULL if the | |
4622 | * kernel pointers should be hidden (so you can just test | |
4623 | * "m->private" to see if you should keep the values private). | |
4624 | * | |
4625 | * We use the same logic as for /proc/kallsyms. | |
4626 | */ | |
3b5d5c6b AD |
4627 | static int modules_open(struct inode *inode, struct file *file) |
4628 | { | |
516fb7f2 LT |
4629 | int err = seq_open(file, &modules_op); |
4630 | ||
4631 | if (!err) { | |
4632 | struct seq_file *m = file->private_data; | |
b25a7c5a | 4633 | m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul; |
516fb7f2 LT |
4634 | } |
4635 | ||
3f553b30 | 4636 | return err; |
3b5d5c6b AD |
4637 | } |
4638 | ||
97a32539 | 4639 | static const struct proc_ops modules_proc_ops = { |
d919b33d | 4640 | .proc_flags = PROC_ENTRY_PERMANENT, |
97a32539 AD |
4641 | .proc_open = modules_open, |
4642 | .proc_read = seq_read, | |
4643 | .proc_lseek = seq_lseek, | |
4644 | .proc_release = seq_release, | |
3b5d5c6b AD |
4645 | }; |
4646 | ||
4647 | static int __init proc_modules_init(void) | |
4648 | { | |
97a32539 | 4649 | proc_create("modules", 0, NULL, &modules_proc_ops); |
3b5d5c6b AD |
4650 | return 0; |
4651 | } | |
4652 | module_init(proc_modules_init); | |
4653 | #endif | |
4654 | ||
1da177e4 LT |
4655 | /* Given an address, look for it in the module exception tables. */ |
4656 | const struct exception_table_entry *search_module_extables(unsigned long addr) | |
4657 | { | |
1da177e4 LT |
4658 | const struct exception_table_entry *e = NULL; |
4659 | struct module *mod; | |
4660 | ||
24da1cbf | 4661 | preempt_disable(); |
5ff22646 PZ |
4662 | mod = __module_address(addr); |
4663 | if (!mod) | |
4664 | goto out; | |
22a8bdeb | 4665 | |
5ff22646 PZ |
4666 | if (!mod->num_exentries) |
4667 | goto out; | |
4668 | ||
4669 | e = search_extable(mod->extable, | |
a94c33dd | 4670 | mod->num_exentries, |
5ff22646 PZ |
4671 | addr); |
4672 | out: | |
24da1cbf | 4673 | preempt_enable(); |
1da177e4 | 4674 | |
5ff22646 PZ |
4675 | /* |
4676 | * Now, if we found one, we are running inside it now, hence | |
4677 | * we cannot unload the module, hence no refcnt needed. | |
4678 | */ | |
1da177e4 LT |
4679 | return e; |
4680 | } | |
4681 | ||
2541743e SS |
4682 | /** |
4683 | * is_module_address() - is this address inside a module? | |
e610499e RR |
4684 | * @addr: the address to check. |
4685 | * | |
4686 | * See is_module_text_address() if you simply want to see if the address | |
4687 | * is code (not data). | |
4d435f9d | 4688 | */ |
e610499e | 4689 | bool is_module_address(unsigned long addr) |
4d435f9d | 4690 | { |
e610499e | 4691 | bool ret; |
4d435f9d | 4692 | |
24da1cbf | 4693 | preempt_disable(); |
e610499e | 4694 | ret = __module_address(addr) != NULL; |
24da1cbf | 4695 | preempt_enable(); |
4d435f9d | 4696 | |
e610499e | 4697 | return ret; |
4d435f9d IM |
4698 | } |
4699 | ||
2541743e SS |
4700 | /** |
4701 | * __module_address() - get the module which contains an address. | |
e610499e RR |
4702 | * @addr: the address. |
4703 | * | |
4704 | * Must be called with preempt disabled or module mutex held so that | |
4705 | * module doesn't get freed during this. | |
4706 | */ | |
714f83d5 | 4707 | struct module *__module_address(unsigned long addr) |
1da177e4 LT |
4708 | { |
4709 | struct module *mod; | |
4710 | ||
3a642e99 RR |
4711 | if (addr < module_addr_min || addr > module_addr_max) |
4712 | return NULL; | |
4713 | ||
0be964be PZ |
4714 | module_assert_mutex_or_preempt(); |
4715 | ||
6c9692e2 | 4716 | mod = mod_find(addr); |
93c2e105 PZ |
4717 | if (mod) { |
4718 | BUG_ON(!within_module(addr, mod)); | |
0d21b0e3 | 4719 | if (mod->state == MODULE_STATE_UNFORMED) |
93c2e105 | 4720 | mod = NULL; |
0d21b0e3 | 4721 | } |
93c2e105 | 4722 | return mod; |
1da177e4 LT |
4723 | } |
4724 | ||
2541743e SS |
4725 | /** |
4726 | * is_module_text_address() - is this address inside module code? | |
e610499e RR |
4727 | * @addr: the address to check. |
4728 | * | |
4729 | * See is_module_address() if you simply want to see if the address is | |
4730 | * anywhere in a module. See kernel_text_address() for testing if an | |
4731 | * address corresponds to kernel or module code. | |
4732 | */ | |
4733 | bool is_module_text_address(unsigned long addr) | |
4734 | { | |
4735 | bool ret; | |
4736 | ||
4737 | preempt_disable(); | |
4738 | ret = __module_text_address(addr) != NULL; | |
4739 | preempt_enable(); | |
4740 | ||
4741 | return ret; | |
4742 | } | |
4743 | ||
2541743e SS |
4744 | /** |
4745 | * __module_text_address() - get the module whose code contains an address. | |
e610499e RR |
4746 | * @addr: the address. |
4747 | * | |
4748 | * Must be called with preempt disabled or module mutex held so that | |
4749 | * module doesn't get freed during this. | |
4750 | */ | |
4751 | struct module *__module_text_address(unsigned long addr) | |
4752 | { | |
4753 | struct module *mod = __module_address(addr); | |
4754 | if (mod) { | |
4755 | /* Make sure it's within the text section. */ | |
7523e4dc RR |
4756 | if (!within(addr, mod->init_layout.base, mod->init_layout.text_size) |
4757 | && !within(addr, mod->core_layout.base, mod->core_layout.text_size)) | |
e610499e RR |
4758 | mod = NULL; |
4759 | } | |
4760 | return mod; | |
4761 | } | |
4762 | ||
1da177e4 LT |
4763 | /* Don't grab lock, we're oopsing. */ |
4764 | void print_modules(void) | |
4765 | { | |
4766 | struct module *mod; | |
7fd8329b | 4767 | char buf[MODULE_FLAGS_BUF_SIZE]; |
1da177e4 | 4768 | |
b231125a | 4769 | printk(KERN_DEFAULT "Modules linked in:"); |
d72b3751 AK |
4770 | /* Most callers should already have preempt disabled, but make sure */ |
4771 | preempt_disable(); | |
0d21b0e3 RR |
4772 | list_for_each_entry_rcu(mod, &modules, list) { |
4773 | if (mod->state == MODULE_STATE_UNFORMED) | |
4774 | continue; | |
27bba4d6 | 4775 | pr_cont(" %s%s", mod->name, module_flags(mod, buf)); |
0d21b0e3 | 4776 | } |
d72b3751 | 4777 | preempt_enable(); |
e14af7ee | 4778 | if (last_unloaded_module[0]) |
27bba4d6 JS |
4779 | pr_cont(" [last unloaded: %s]", last_unloaded_module); |
4780 | pr_cont("\n"); | |
1da177e4 LT |
4781 | } |
4782 | ||
1da177e4 | 4783 | #ifdef CONFIG_MODVERSIONS |
24b9f0d2 SS |
4784 | /* |
4785 | * Generate the signature for all relevant module structures here. | |
4786 | * If these change, we don't want to try to parse the module. | |
4787 | */ | |
8c8ef42a RR |
4788 | void module_layout(struct module *mod, |
4789 | struct modversion_info *ver, | |
4790 | struct kernel_param *kp, | |
4791 | struct kernel_symbol *ks, | |
65498646 | 4792 | struct tracepoint * const *tp) |
8c8ef42a RR |
4793 | { |
4794 | } | |
4795 | EXPORT_SYMBOL(module_layout); | |
1da177e4 | 4796 | #endif |