]>
Commit | Line | Data |
---|---|---|
1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
f71d20e9 | 2 | /* |
1da177e4 | 3 | Copyright (C) 2002 Richard Henderson |
51f3d0f4 | 4 | Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM. |
1da177e4 | 5 | |
1da177e4 | 6 | */ |
9984de1a | 7 | #include <linux/export.h> |
8a293be0 | 8 | #include <linux/extable.h> |
1da177e4 | 9 | #include <linux/moduleloader.h> |
c8424e77 | 10 | #include <linux/module_signature.h> |
af658dca | 11 | #include <linux/trace_events.h> |
1da177e4 | 12 | #include <linux/init.h> |
ae84e324 | 13 | #include <linux/kallsyms.h> |
34e1169d | 14 | #include <linux/file.h> |
3b5d5c6b | 15 | #include <linux/fs.h> |
6d760133 | 16 | #include <linux/sysfs.h> |
9f158333 | 17 | #include <linux/kernel.h> |
1da177e4 LT |
18 | #include <linux/slab.h> |
19 | #include <linux/vmalloc.h> | |
20 | #include <linux/elf.h> | |
3b5d5c6b | 21 | #include <linux/proc_fs.h> |
2e72d51b | 22 | #include <linux/security.h> |
1da177e4 LT |
23 | #include <linux/seq_file.h> |
24 | #include <linux/syscalls.h> | |
25 | #include <linux/fcntl.h> | |
26 | #include <linux/rcupdate.h> | |
c59ede7b | 27 | #include <linux/capability.h> |
1da177e4 LT |
28 | #include <linux/cpu.h> |
29 | #include <linux/moduleparam.h> | |
30 | #include <linux/errno.h> | |
31 | #include <linux/err.h> | |
32 | #include <linux/vermagic.h> | |
33 | #include <linux/notifier.h> | |
f6a57033 | 34 | #include <linux/sched.h> |
1da177e4 | 35 | #include <linux/device.h> |
c988d2b2 | 36 | #include <linux/string.h> |
97d1f15b | 37 | #include <linux/mutex.h> |
d72b3751 | 38 | #include <linux/rculist.h> |
7c0f6ba6 | 39 | #include <linux/uaccess.h> |
1da177e4 | 40 | #include <asm/cacheflush.h> |
563ec5cb | 41 | #include <linux/set_memory.h> |
eb8cdec4 | 42 | #include <asm/mmu_context.h> |
b817f6fe | 43 | #include <linux/license.h> |
6d762394 | 44 | #include <asm/sections.h> |
97e1c18e | 45 | #include <linux/tracepoint.h> |
90d595fe | 46 | #include <linux/ftrace.h> |
7e545d6e | 47 | #include <linux/livepatch.h> |
22a9d645 | 48 | #include <linux/async.h> |
fbf59bc9 | 49 | #include <linux/percpu.h> |
4f2294b6 | 50 | #include <linux/kmemleak.h> |
bf5438fc | 51 | #include <linux/jump_label.h> |
84e1c6bb | 52 | #include <linux/pfn.h> |
403ed278 | 53 | #include <linux/bsearch.h> |
9d5059c9 | 54 | #include <linux/dynamic_debug.h> |
ca86cad7 | 55 | #include <linux/audit.h> |
2f3238ae | 56 | #include <uapi/linux/module.h> |
106a4ee2 | 57 | #include "module-internal.h" |
1da177e4 | 58 | |
7ead8b83 LZ |
59 | #define CREATE_TRACE_POINTS |
60 | #include <trace/events/module.h> | |
61 | ||
1da177e4 LT |
62 | #ifndef ARCH_SHF_SMALL |
63 | #define ARCH_SHF_SMALL 0 | |
64 | #endif | |
65 | ||
84e1c6bb MC |
66 | /* |
67 | * Modules' sections will be aligned on page boundaries | |
3b5be16c HZ |
68 | * to ensure complete separation of code and data, but |
69 | * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y | |
84e1c6bb | 70 | */ |
3b5be16c | 71 | #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX |
84e1c6bb | 72 | # define debug_align(X) ALIGN(X, PAGE_SIZE) |
3b5be16c HZ |
73 | #else |
74 | # define debug_align(X) (X) | |
75 | #endif | |
84e1c6bb | 76 | |
1da177e4 LT |
77 | /* If this is set, the section belongs in the init part of the module */ |
78 | #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) | |
79 | ||
75676500 RR |
80 | /* |
81 | * Mutex protects: | |
82 | * 1) List of modules (also safely readable with preempt_disable), | |
83 | * 2) module_use links, | |
84 | * 3) module_addr_min/module_addr_max. | |
e513cc1c | 85 | * (delete and add uses RCU list operations). */ |
c6b37801 TA |
86 | DEFINE_MUTEX(module_mutex); |
87 | EXPORT_SYMBOL_GPL(module_mutex); | |
1da177e4 | 88 | static LIST_HEAD(modules); |
67fc4e0c | 89 | |
1a7b7d92 | 90 | /* Work queue for freeing init sections in success case */ |
17eb959c DJ |
91 | static void do_free_init(struct work_struct *w); |
92 | static DECLARE_WORK(init_free_wq, do_free_init); | |
93 | static LLIST_HEAD(init_free_list); | |
1a7b7d92 | 94 | |
6c9692e2 | 95 | #ifdef CONFIG_MODULES_TREE_LOOKUP |
106a4ee2 | 96 | |
93c2e105 PZ |
97 | /* |
98 | * Use a latched RB-tree for __module_address(); this allows us to use | |
99 | * RCU-sched lookups of the address from any context. | |
100 | * | |
6c9692e2 PZ |
101 | * This is conditional on PERF_EVENTS || TRACING because those can really hit |
102 | * __module_address() hard by doing a lot of stack unwinding; potentially from | |
103 | * NMI context. | |
93c2e105 PZ |
104 | */ |
105 | ||
106 | static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n) | |
106a4ee2 | 107 | { |
7523e4dc | 108 | struct module_layout *layout = container_of(n, struct module_layout, mtn.node); |
106a4ee2 | 109 | |
7523e4dc | 110 | return (unsigned long)layout->base; |
93c2e105 PZ |
111 | } |
112 | ||
113 | static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n) | |
114 | { | |
7523e4dc | 115 | struct module_layout *layout = container_of(n, struct module_layout, mtn.node); |
93c2e105 | 116 | |
7523e4dc | 117 | return (unsigned long)layout->size; |
93c2e105 PZ |
118 | } |
119 | ||
120 | static __always_inline bool | |
121 | mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b) | |
122 | { | |
123 | return __mod_tree_val(a) < __mod_tree_val(b); | |
124 | } | |
125 | ||
126 | static __always_inline int | |
127 | mod_tree_comp(void *key, struct latch_tree_node *n) | |
128 | { | |
129 | unsigned long val = (unsigned long)key; | |
130 | unsigned long start, end; | |
131 | ||
132 | start = __mod_tree_val(n); | |
133 | if (val < start) | |
134 | return -1; | |
135 | ||
136 | end = start + __mod_tree_size(n); | |
137 | if (val >= end) | |
138 | return 1; | |
106a4ee2 | 139 | |
106a4ee2 RR |
140 | return 0; |
141 | } | |
142 | ||
93c2e105 PZ |
143 | static const struct latch_tree_ops mod_tree_ops = { |
144 | .less = mod_tree_less, | |
145 | .comp = mod_tree_comp, | |
146 | }; | |
147 | ||
4f666546 PZ |
148 | static struct mod_tree_root { |
149 | struct latch_tree_root root; | |
150 | unsigned long addr_min; | |
151 | unsigned long addr_max; | |
152 | } mod_tree __cacheline_aligned = { | |
153 | .addr_min = -1UL, | |
106a4ee2 | 154 | }; |
106a4ee2 | 155 | |
4f666546 PZ |
156 | #define module_addr_min mod_tree.addr_min |
157 | #define module_addr_max mod_tree.addr_max | |
158 | ||
159 | static noinline void __mod_tree_insert(struct mod_tree_node *node) | |
160 | { | |
161 | latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops); | |
162 | } | |
163 | ||
164 | static void __mod_tree_remove(struct mod_tree_node *node) | |
165 | { | |
166 | latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops); | |
167 | } | |
93c2e105 PZ |
168 | |
169 | /* | |
170 | * These modifications: insert, remove_init and remove; are serialized by the | |
171 | * module_mutex. | |
172 | */ | |
173 | static void mod_tree_insert(struct module *mod) | |
174 | { | |
7523e4dc RR |
175 | mod->core_layout.mtn.mod = mod; |
176 | mod->init_layout.mtn.mod = mod; | |
93c2e105 | 177 | |
7523e4dc RR |
178 | __mod_tree_insert(&mod->core_layout.mtn); |
179 | if (mod->init_layout.size) | |
180 | __mod_tree_insert(&mod->init_layout.mtn); | |
93c2e105 PZ |
181 | } |
182 | ||
183 | static void mod_tree_remove_init(struct module *mod) | |
184 | { | |
7523e4dc RR |
185 | if (mod->init_layout.size) |
186 | __mod_tree_remove(&mod->init_layout.mtn); | |
93c2e105 PZ |
187 | } |
188 | ||
189 | static void mod_tree_remove(struct module *mod) | |
190 | { | |
7523e4dc | 191 | __mod_tree_remove(&mod->core_layout.mtn); |
93c2e105 PZ |
192 | mod_tree_remove_init(mod); |
193 | } | |
194 | ||
6c9692e2 | 195 | static struct module *mod_find(unsigned long addr) |
93c2e105 PZ |
196 | { |
197 | struct latch_tree_node *ltn; | |
198 | ||
4f666546 | 199 | ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops); |
93c2e105 PZ |
200 | if (!ltn) |
201 | return NULL; | |
202 | ||
203 | return container_of(ltn, struct mod_tree_node, node)->mod; | |
204 | } | |
205 | ||
6c9692e2 PZ |
206 | #else /* MODULES_TREE_LOOKUP */ |
207 | ||
4f666546 PZ |
208 | static unsigned long module_addr_min = -1UL, module_addr_max = 0; |
209 | ||
6c9692e2 PZ |
210 | static void mod_tree_insert(struct module *mod) { } |
211 | static void mod_tree_remove_init(struct module *mod) { } | |
212 | static void mod_tree_remove(struct module *mod) { } | |
213 | ||
214 | static struct module *mod_find(unsigned long addr) | |
215 | { | |
216 | struct module *mod; | |
217 | ||
135cc111 MH |
218 | list_for_each_entry_rcu(mod, &modules, list, |
219 | lockdep_is_held(&module_mutex)) { | |
6c9692e2 PZ |
220 | if (within_module(addr, mod)) |
221 | return mod; | |
222 | } | |
223 | ||
224 | return NULL; | |
225 | } | |
226 | ||
227 | #endif /* MODULES_TREE_LOOKUP */ | |
228 | ||
4f666546 PZ |
229 | /* |
230 | * Bounds of module text, for speeding up __module_address. | |
231 | * Protected by module_mutex. | |
232 | */ | |
233 | static void __mod_update_bounds(void *base, unsigned int size) | |
234 | { | |
235 | unsigned long min = (unsigned long)base; | |
236 | unsigned long max = min + size; | |
237 | ||
238 | if (min < module_addr_min) | |
239 | module_addr_min = min; | |
240 | if (max > module_addr_max) | |
241 | module_addr_max = max; | |
242 | } | |
243 | ||
244 | static void mod_update_bounds(struct module *mod) | |
245 | { | |
7523e4dc RR |
246 | __mod_update_bounds(mod->core_layout.base, mod->core_layout.size); |
247 | if (mod->init_layout.size) | |
248 | __mod_update_bounds(mod->init_layout.base, mod->init_layout.size); | |
4f666546 PZ |
249 | } |
250 | ||
67fc4e0c JW |
251 | #ifdef CONFIG_KGDB_KDB |
252 | struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ | |
253 | #endif /* CONFIG_KGDB_KDB */ | |
254 | ||
0be964be PZ |
255 | static void module_assert_mutex(void) |
256 | { | |
257 | lockdep_assert_held(&module_mutex); | |
258 | } | |
259 | ||
260 | static void module_assert_mutex_or_preempt(void) | |
261 | { | |
262 | #ifdef CONFIG_LOCKDEP | |
263 | if (unlikely(!debug_locks)) | |
264 | return; | |
265 | ||
9502514f | 266 | WARN_ON_ONCE(!rcu_read_lock_sched_held() && |
0be964be PZ |
267 | !lockdep_is_held(&module_mutex)); |
268 | #endif | |
269 | } | |
270 | ||
c8914756 | 271 | #ifdef CONFIG_MODULE_SIG |
6727bb9c | 272 | static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE); |
106a4ee2 | 273 | module_param(sig_enforce, bool_enable_only, 0644); |
1da177e4 | 274 | |
c8914756 MZ |
275 | void set_module_sig_enforced(void) |
276 | { | |
277 | sig_enforce = true; | |
278 | } | |
279 | #else | |
280 | #define sig_enforce false | |
281 | #endif | |
282 | ||
fda784e5 BM |
283 | /* |
284 | * Export sig_enforce kernel cmdline parameter to allow other subsystems rely | |
285 | * on that instead of directly to CONFIG_MODULE_SIG_FORCE config. | |
286 | */ | |
287 | bool is_module_sig_enforced(void) | |
288 | { | |
289 | return sig_enforce; | |
290 | } | |
291 | EXPORT_SYMBOL(is_module_sig_enforced); | |
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 | ||
1da177e4 LT |
383 | /* Provided by the linker */ |
384 | extern const struct kernel_symbol __start___ksymtab[]; | |
385 | extern const struct kernel_symbol __stop___ksymtab[]; | |
386 | extern const struct kernel_symbol __start___ksymtab_gpl[]; | |
387 | extern const struct kernel_symbol __stop___ksymtab_gpl[]; | |
9f28bb7e GKH |
388 | extern const struct kernel_symbol __start___ksymtab_gpl_future[]; |
389 | extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; | |
71810db2 AB |
390 | extern const s32 __start___kcrctab[]; |
391 | extern const s32 __start___kcrctab_gpl[]; | |
392 | extern const s32 __start___kcrctab_gpl_future[]; | |
f7f5b675 DV |
393 | #ifdef CONFIG_UNUSED_SYMBOLS |
394 | extern const struct kernel_symbol __start___ksymtab_unused[]; | |
395 | extern const struct kernel_symbol __stop___ksymtab_unused[]; | |
396 | extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; | |
397 | extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; | |
71810db2 AB |
398 | extern const s32 __start___kcrctab_unused[]; |
399 | extern const s32 __start___kcrctab_unused_gpl[]; | |
f7f5b675 | 400 | #endif |
1da177e4 LT |
401 | |
402 | #ifndef CONFIG_MODVERSIONS | |
403 | #define symversion(base, idx) NULL | |
404 | #else | |
f83ca9fe | 405 | #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL) |
1da177e4 LT |
406 | #endif |
407 | ||
dafd0940 RR |
408 | static bool each_symbol_in_section(const struct symsearch *arr, |
409 | unsigned int arrsize, | |
410 | struct module *owner, | |
411 | bool (*fn)(const struct symsearch *syms, | |
412 | struct module *owner, | |
de4d8d53 | 413 | void *data), |
dafd0940 | 414 | void *data) |
ad9546c9 | 415 | { |
de4d8d53 | 416 | unsigned int j; |
ad9546c9 | 417 | |
dafd0940 | 418 | for (j = 0; j < arrsize; j++) { |
de4d8d53 RR |
419 | if (fn(&arr[j], owner, data)) |
420 | return true; | |
f71d20e9 | 421 | } |
dafd0940 RR |
422 | |
423 | return false; | |
ad9546c9 RR |
424 | } |
425 | ||
dafd0940 | 426 | /* Returns true as soon as fn returns true, otherwise false. */ |
4446ec44 | 427 | bool each_symbol_section(bool (*fn)(const struct symsearch *arr, |
de4d8d53 RR |
428 | struct module *owner, |
429 | void *data), | |
430 | void *data) | |
ad9546c9 RR |
431 | { |
432 | struct module *mod; | |
44032e63 | 433 | static const struct symsearch arr[] = { |
ad9546c9 | 434 | { __start___ksymtab, __stop___ksymtab, __start___kcrctab, |
dafd0940 | 435 | NOT_GPL_ONLY, false }, |
ad9546c9 | 436 | { __start___ksymtab_gpl, __stop___ksymtab_gpl, |
dafd0940 RR |
437 | __start___kcrctab_gpl, |
438 | GPL_ONLY, false }, | |
ad9546c9 | 439 | { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future, |
dafd0940 RR |
440 | __start___kcrctab_gpl_future, |
441 | WILL_BE_GPL_ONLY, false }, | |
f7f5b675 | 442 | #ifdef CONFIG_UNUSED_SYMBOLS |
ad9546c9 | 443 | { __start___ksymtab_unused, __stop___ksymtab_unused, |
dafd0940 RR |
444 | __start___kcrctab_unused, |
445 | NOT_GPL_ONLY, true }, | |
ad9546c9 | 446 | { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl, |
dafd0940 RR |
447 | __start___kcrctab_unused_gpl, |
448 | GPL_ONLY, true }, | |
f7f5b675 | 449 | #endif |
ad9546c9 | 450 | }; |
f71d20e9 | 451 | |
0be964be PZ |
452 | module_assert_mutex_or_preempt(); |
453 | ||
dafd0940 RR |
454 | if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data)) |
455 | return true; | |
f71d20e9 | 456 | |
135cc111 MH |
457 | list_for_each_entry_rcu(mod, &modules, list, |
458 | lockdep_is_held(&module_mutex)) { | |
ad9546c9 RR |
459 | struct symsearch arr[] = { |
460 | { mod->syms, mod->syms + mod->num_syms, mod->crcs, | |
dafd0940 | 461 | NOT_GPL_ONLY, false }, |
ad9546c9 | 462 | { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, |
dafd0940 RR |
463 | mod->gpl_crcs, |
464 | GPL_ONLY, false }, | |
ad9546c9 RR |
465 | { mod->gpl_future_syms, |
466 | mod->gpl_future_syms + mod->num_gpl_future_syms, | |
dafd0940 RR |
467 | mod->gpl_future_crcs, |
468 | WILL_BE_GPL_ONLY, false }, | |
f7f5b675 | 469 | #ifdef CONFIG_UNUSED_SYMBOLS |
ad9546c9 RR |
470 | { mod->unused_syms, |
471 | mod->unused_syms + mod->num_unused_syms, | |
dafd0940 RR |
472 | mod->unused_crcs, |
473 | NOT_GPL_ONLY, true }, | |
ad9546c9 RR |
474 | { mod->unused_gpl_syms, |
475 | mod->unused_gpl_syms + mod->num_unused_gpl_syms, | |
dafd0940 RR |
476 | mod->unused_gpl_crcs, |
477 | GPL_ONLY, true }, | |
f7f5b675 | 478 | #endif |
ad9546c9 RR |
479 | }; |
480 | ||
0d21b0e3 RR |
481 | if (mod->state == MODULE_STATE_UNFORMED) |
482 | continue; | |
483 | ||
dafd0940 RR |
484 | if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data)) |
485 | return true; | |
486 | } | |
487 | return false; | |
488 | } | |
4446ec44 | 489 | EXPORT_SYMBOL_GPL(each_symbol_section); |
dafd0940 RR |
490 | |
491 | struct find_symbol_arg { | |
492 | /* Input */ | |
493 | const char *name; | |
494 | bool gplok; | |
495 | bool warn; | |
496 | ||
497 | /* Output */ | |
498 | struct module *owner; | |
71810db2 | 499 | const s32 *crc; |
414fd31b | 500 | const struct kernel_symbol *sym; |
dafd0940 RR |
501 | }; |
502 | ||
2d25bc55 JY |
503 | static bool check_exported_symbol(const struct symsearch *syms, |
504 | struct module *owner, | |
505 | unsigned int symnum, void *data) | |
dafd0940 RR |
506 | { |
507 | struct find_symbol_arg *fsa = data; | |
508 | ||
dafd0940 | 509 | if (!fsa->gplok) { |
db4a1439 | 510 | if (syms->licence == GPL_ONLY) |
dafd0940 | 511 | return false; |
db4a1439 | 512 | if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) { |
bddb12b3 AM |
513 | pr_warn("Symbol %s is being used by a non-GPL module, " |
514 | "which will not be allowed in the future\n", | |
515 | fsa->name); | |
9f28bb7e | 516 | } |
1da177e4 | 517 | } |
ad9546c9 | 518 | |
f7f5b675 | 519 | #ifdef CONFIG_UNUSED_SYMBOLS |
dafd0940 | 520 | if (syms->unused && fsa->warn) { |
bddb12b3 AM |
521 | pr_warn("Symbol %s is marked as UNUSED, however this module is " |
522 | "using it.\n", fsa->name); | |
523 | pr_warn("This symbol will go away in the future.\n"); | |
7b63c3ab YG |
524 | pr_warn("Please evaluate if this is the right api to use and " |
525 | "if it really is, submit a report to the linux kernel " | |
526 | "mailing list together with submitting your code for " | |
bddb12b3 | 527 | "inclusion.\n"); |
dafd0940 | 528 | } |
f7f5b675 | 529 | #endif |
dafd0940 RR |
530 | |
531 | fsa->owner = owner; | |
532 | fsa->crc = symversion(syms->crcs, symnum); | |
414fd31b | 533 | fsa->sym = &syms->start[symnum]; |
dafd0940 RR |
534 | return true; |
535 | } | |
536 | ||
7290d580 AB |
537 | static unsigned long kernel_symbol_value(const struct kernel_symbol *sym) |
538 | { | |
539 | #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS | |
540 | return (unsigned long)offset_to_ptr(&sym->value_offset); | |
541 | #else | |
542 | return sym->value; | |
543 | #endif | |
544 | } | |
545 | ||
546 | static const char *kernel_symbol_name(const struct kernel_symbol *sym) | |
547 | { | |
548 | #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS | |
549 | return offset_to_ptr(&sym->name_offset); | |
550 | #else | |
551 | return sym->name; | |
552 | #endif | |
553 | } | |
554 | ||
8651ec01 MM |
555 | static const char *kernel_symbol_namespace(const struct kernel_symbol *sym) |
556 | { | |
557 | #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS | |
069e1c07 WD |
558 | if (!sym->namespace_offset) |
559 | return NULL; | |
8651ec01 MM |
560 | return offset_to_ptr(&sym->namespace_offset); |
561 | #else | |
562 | return sym->namespace; | |
563 | #endif | |
564 | } | |
565 | ||
b605be65 | 566 | static int cmp_name(const void *name, const void *sym) |
403ed278 | 567 | { |
b605be65 | 568 | return strcmp(name, kernel_symbol_name(sym)); |
403ed278 AIB |
569 | } |
570 | ||
2d25bc55 JY |
571 | static bool find_exported_symbol_in_section(const struct symsearch *syms, |
572 | struct module *owner, | |
573 | void *data) | |
de4d8d53 RR |
574 | { |
575 | struct find_symbol_arg *fsa = data; | |
403ed278 AIB |
576 | struct kernel_symbol *sym; |
577 | ||
578 | sym = bsearch(fsa->name, syms->start, syms->stop - syms->start, | |
579 | sizeof(struct kernel_symbol), cmp_name); | |
580 | ||
2d25bc55 JY |
581 | if (sym != NULL && check_exported_symbol(syms, owner, |
582 | sym - syms->start, data)) | |
403ed278 | 583 | return true; |
de4d8d53 | 584 | |
de4d8d53 RR |
585 | return false; |
586 | } | |
587 | ||
2d25bc55 | 588 | /* Find an exported symbol and return it, along with, (optional) crc and |
75676500 | 589 | * (optional) module which owns it. Needs preempt disabled or module_mutex. */ |
82a45d38 | 590 | const struct kernel_symbol *find_symbol(const char *name, |
c6b37801 | 591 | struct module **owner, |
71810db2 | 592 | const s32 **crc, |
c6b37801 TA |
593 | bool gplok, |
594 | bool warn) | |
dafd0940 RR |
595 | { |
596 | struct find_symbol_arg fsa; | |
597 | ||
598 | fsa.name = name; | |
599 | fsa.gplok = gplok; | |
600 | fsa.warn = warn; | |
601 | ||
2d25bc55 | 602 | if (each_symbol_section(find_exported_symbol_in_section, &fsa)) { |
dafd0940 RR |
603 | if (owner) |
604 | *owner = fsa.owner; | |
605 | if (crc) | |
606 | *crc = fsa.crc; | |
414fd31b | 607 | return fsa.sym; |
dafd0940 RR |
608 | } |
609 | ||
5e124169 | 610 | pr_debug("Failed to find symbol %s\n", name); |
414fd31b | 611 | return NULL; |
1da177e4 | 612 | } |
82a45d38 | 613 | EXPORT_SYMBOL_GPL(find_symbol); |
1da177e4 | 614 | |
fe0d34d2 RR |
615 | /* |
616 | * Search for module by name: must hold module_mutex (or preempt disabled | |
617 | * for read-only access). | |
618 | */ | |
4f6de4d5 | 619 | static struct module *find_module_all(const char *name, size_t len, |
0d21b0e3 | 620 | bool even_unformed) |
1da177e4 LT |
621 | { |
622 | struct module *mod; | |
623 | ||
fe0d34d2 | 624 | module_assert_mutex_or_preempt(); |
0be964be | 625 | |
135cc111 MH |
626 | list_for_each_entry_rcu(mod, &modules, list, |
627 | lockdep_is_held(&module_mutex)) { | |
0d21b0e3 RR |
628 | if (!even_unformed && mod->state == MODULE_STATE_UNFORMED) |
629 | continue; | |
4f6de4d5 | 630 | if (strlen(mod->name) == len && !memcmp(mod->name, name, len)) |
1da177e4 LT |
631 | return mod; |
632 | } | |
633 | return NULL; | |
634 | } | |
0d21b0e3 RR |
635 | |
636 | struct module *find_module(const char *name) | |
637 | { | |
fe0d34d2 | 638 | module_assert_mutex(); |
4f6de4d5 | 639 | return find_module_all(name, strlen(name), false); |
0d21b0e3 | 640 | } |
c6b37801 | 641 | EXPORT_SYMBOL_GPL(find_module); |
1da177e4 LT |
642 | |
643 | #ifdef CONFIG_SMP | |
fbf59bc9 | 644 | |
259354de | 645 | static inline void __percpu *mod_percpu(struct module *mod) |
fbf59bc9 | 646 | { |
259354de TH |
647 | return mod->percpu; |
648 | } | |
fbf59bc9 | 649 | |
9eb76d77 | 650 | static int percpu_modalloc(struct module *mod, struct load_info *info) |
259354de | 651 | { |
9eb76d77 RR |
652 | Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu]; |
653 | unsigned long align = pcpusec->sh_addralign; | |
654 | ||
655 | if (!pcpusec->sh_size) | |
656 | return 0; | |
657 | ||
fbf59bc9 | 658 | if (align > PAGE_SIZE) { |
bddb12b3 AM |
659 | pr_warn("%s: per-cpu alignment %li > %li\n", |
660 | mod->name, align, PAGE_SIZE); | |
fbf59bc9 TH |
661 | align = PAGE_SIZE; |
662 | } | |
663 | ||
9eb76d77 | 664 | mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align); |
259354de | 665 | if (!mod->percpu) { |
bddb12b3 AM |
666 | pr_warn("%s: Could not allocate %lu bytes percpu data\n", |
667 | mod->name, (unsigned long)pcpusec->sh_size); | |
259354de TH |
668 | return -ENOMEM; |
669 | } | |
9eb76d77 | 670 | mod->percpu_size = pcpusec->sh_size; |
259354de | 671 | return 0; |
fbf59bc9 TH |
672 | } |
673 | ||
259354de | 674 | static void percpu_modfree(struct module *mod) |
fbf59bc9 | 675 | { |
259354de | 676 | free_percpu(mod->percpu); |
fbf59bc9 TH |
677 | } |
678 | ||
49668688 | 679 | static unsigned int find_pcpusec(struct load_info *info) |
6b588c18 | 680 | { |
49668688 | 681 | return find_sec(info, ".data..percpu"); |
6b588c18 TH |
682 | } |
683 | ||
259354de TH |
684 | static void percpu_modcopy(struct module *mod, |
685 | const void *from, unsigned long size) | |
6b588c18 TH |
686 | { |
687 | int cpu; | |
688 | ||
689 | for_each_possible_cpu(cpu) | |
259354de | 690 | memcpy(per_cpu_ptr(mod->percpu, cpu), from, size); |
6b588c18 TH |
691 | } |
692 | ||
383776fa | 693 | bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr) |
10fad5e4 TH |
694 | { |
695 | struct module *mod; | |
696 | unsigned int cpu; | |
697 | ||
698 | preempt_disable(); | |
699 | ||
700 | list_for_each_entry_rcu(mod, &modules, list) { | |
0d21b0e3 RR |
701 | if (mod->state == MODULE_STATE_UNFORMED) |
702 | continue; | |
10fad5e4 TH |
703 | if (!mod->percpu_size) |
704 | continue; | |
705 | for_each_possible_cpu(cpu) { | |
706 | void *start = per_cpu_ptr(mod->percpu, cpu); | |
383776fa | 707 | void *va = (void *)addr; |
10fad5e4 | 708 | |
383776fa | 709 | if (va >= start && va < start + mod->percpu_size) { |
8ce371f9 | 710 | if (can_addr) { |
383776fa | 711 | *can_addr = (unsigned long) (va - start); |
8ce371f9 PZ |
712 | *can_addr += (unsigned long) |
713 | per_cpu_ptr(mod->percpu, | |
714 | get_boot_cpu_id()); | |
715 | } | |
10fad5e4 TH |
716 | preempt_enable(); |
717 | return true; | |
718 | } | |
719 | } | |
720 | } | |
721 | ||
722 | preempt_enable(); | |
723 | return false; | |
6b588c18 TH |
724 | } |
725 | ||
383776fa TG |
726 | /** |
727 | * is_module_percpu_address - test whether address is from module static percpu | |
728 | * @addr: address to test | |
729 | * | |
730 | * Test whether @addr belongs to module static percpu area. | |
731 | * | |
732 | * RETURNS: | |
733 | * %true if @addr is from module static percpu area | |
734 | */ | |
735 | bool is_module_percpu_address(unsigned long addr) | |
736 | { | |
737 | return __is_module_percpu_address(addr, NULL); | |
738 | } | |
739 | ||
1da177e4 | 740 | #else /* ... !CONFIG_SMP */ |
6b588c18 | 741 | |
259354de | 742 | static inline void __percpu *mod_percpu(struct module *mod) |
1da177e4 LT |
743 | { |
744 | return NULL; | |
745 | } | |
9eb76d77 | 746 | static int percpu_modalloc(struct module *mod, struct load_info *info) |
259354de | 747 | { |
9eb76d77 RR |
748 | /* UP modules shouldn't have this section: ENOMEM isn't quite right */ |
749 | if (info->sechdrs[info->index.pcpu].sh_size != 0) | |
750 | return -ENOMEM; | |
751 | return 0; | |
259354de TH |
752 | } |
753 | static inline void percpu_modfree(struct module *mod) | |
1da177e4 | 754 | { |
1da177e4 | 755 | } |
49668688 | 756 | static unsigned int find_pcpusec(struct load_info *info) |
1da177e4 LT |
757 | { |
758 | return 0; | |
759 | } | |
259354de TH |
760 | static inline void percpu_modcopy(struct module *mod, |
761 | const void *from, unsigned long size) | |
1da177e4 LT |
762 | { |
763 | /* pcpusec should be 0, and size of that section should be 0. */ | |
764 | BUG_ON(size != 0); | |
765 | } | |
10fad5e4 TH |
766 | bool is_module_percpu_address(unsigned long addr) |
767 | { | |
768 | return false; | |
769 | } | |
6b588c18 | 770 | |
383776fa TG |
771 | bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr) |
772 | { | |
773 | return false; | |
774 | } | |
775 | ||
1da177e4 LT |
776 | #endif /* CONFIG_SMP */ |
777 | ||
c988d2b2 MD |
778 | #define MODINFO_ATTR(field) \ |
779 | static void setup_modinfo_##field(struct module *mod, const char *s) \ | |
780 | { \ | |
781 | mod->field = kstrdup(s, GFP_KERNEL); \ | |
782 | } \ | |
783 | static ssize_t show_modinfo_##field(struct module_attribute *mattr, \ | |
4befb026 | 784 | struct module_kobject *mk, char *buffer) \ |
c988d2b2 | 785 | { \ |
cc56ded3 | 786 | return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \ |
c988d2b2 MD |
787 | } \ |
788 | static int modinfo_##field##_exists(struct module *mod) \ | |
789 | { \ | |
790 | return mod->field != NULL; \ | |
791 | } \ | |
792 | static void free_modinfo_##field(struct module *mod) \ | |
793 | { \ | |
22a8bdeb DW |
794 | kfree(mod->field); \ |
795 | mod->field = NULL; \ | |
c988d2b2 MD |
796 | } \ |
797 | static struct module_attribute modinfo_##field = { \ | |
7b595756 | 798 | .attr = { .name = __stringify(field), .mode = 0444 }, \ |
c988d2b2 MD |
799 | .show = show_modinfo_##field, \ |
800 | .setup = setup_modinfo_##field, \ | |
801 | .test = modinfo_##field##_exists, \ | |
802 | .free = free_modinfo_##field, \ | |
803 | }; | |
804 | ||
805 | MODINFO_ATTR(version); | |
806 | MODINFO_ATTR(srcversion); | |
807 | ||
e14af7ee AV |
808 | static char last_unloaded_module[MODULE_NAME_LEN+1]; |
809 | ||
03e88ae1 | 810 | #ifdef CONFIG_MODULE_UNLOAD |
eb0c5377 SR |
811 | |
812 | EXPORT_TRACEPOINT_SYMBOL(module_get); | |
813 | ||
e513cc1c MH |
814 | /* MODULE_REF_BASE is the base reference count by kmodule loader. */ |
815 | #define MODULE_REF_BASE 1 | |
816 | ||
1da177e4 | 817 | /* Init the unload section of the module. */ |
9f85a4bb | 818 | static int module_unload_init(struct module *mod) |
1da177e4 | 819 | { |
e513cc1c MH |
820 | /* |
821 | * Initialize reference counter to MODULE_REF_BASE. | |
822 | * refcnt == 0 means module is going. | |
823 | */ | |
824 | atomic_set(&mod->refcnt, MODULE_REF_BASE); | |
9f85a4bb | 825 | |
2c02dfe7 LT |
826 | INIT_LIST_HEAD(&mod->source_list); |
827 | INIT_LIST_HEAD(&mod->target_list); | |
e1783a24 | 828 | |
1da177e4 | 829 | /* Hold reference count during initialization. */ |
e513cc1c | 830 | atomic_inc(&mod->refcnt); |
9f85a4bb RR |
831 | |
832 | return 0; | |
1da177e4 LT |
833 | } |
834 | ||
1da177e4 LT |
835 | /* Does a already use b? */ |
836 | static int already_uses(struct module *a, struct module *b) | |
837 | { | |
838 | struct module_use *use; | |
839 | ||
2c02dfe7 LT |
840 | list_for_each_entry(use, &b->source_list, source_list) { |
841 | if (use->source == a) { | |
5e124169 | 842 | pr_debug("%s uses %s!\n", a->name, b->name); |
1da177e4 LT |
843 | return 1; |
844 | } | |
845 | } | |
5e124169 | 846 | pr_debug("%s does not use %s!\n", a->name, b->name); |
1da177e4 LT |
847 | return 0; |
848 | } | |
849 | ||
2c02dfe7 LT |
850 | /* |
851 | * Module a uses b | |
852 | * - we add 'a' as a "source", 'b' as a "target" of module use | |
853 | * - the module_use is added to the list of 'b' sources (so | |
854 | * 'b' can walk the list to see who sourced them), and of 'a' | |
855 | * targets (so 'a' can see what modules it targets). | |
856 | */ | |
857 | static int add_module_usage(struct module *a, struct module *b) | |
858 | { | |
2c02dfe7 LT |
859 | struct module_use *use; |
860 | ||
5e124169 | 861 | pr_debug("Allocating new usage for %s.\n", a->name); |
2c02dfe7 | 862 | use = kmalloc(sizeof(*use), GFP_ATOMIC); |
9ad04574 | 863 | if (!use) |
2c02dfe7 | 864 | return -ENOMEM; |
2c02dfe7 LT |
865 | |
866 | use->source = a; | |
867 | use->target = b; | |
868 | list_add(&use->source_list, &b->source_list); | |
869 | list_add(&use->target_list, &a->target_list); | |
2c02dfe7 LT |
870 | return 0; |
871 | } | |
872 | ||
75676500 | 873 | /* Module a uses b: caller needs module_mutex() */ |
913f6eb4 | 874 | int ref_module(struct module *a, struct module *b) |
1da177e4 | 875 | { |
c8e21ced | 876 | int err; |
270a6c4c | 877 | |
9bea7f23 | 878 | if (b == NULL || already_uses(a, b)) |
218ce735 | 879 | return 0; |
218ce735 | 880 | |
9bea7f23 RR |
881 | /* If module isn't available, we fail. */ |
882 | err = strong_try_module_get(b); | |
c9a3ba55 | 883 | if (err) |
9bea7f23 | 884 | return err; |
1da177e4 | 885 | |
2c02dfe7 LT |
886 | err = add_module_usage(a, b); |
887 | if (err) { | |
1da177e4 | 888 | module_put(b); |
9bea7f23 | 889 | return err; |
1da177e4 | 890 | } |
9bea7f23 | 891 | return 0; |
1da177e4 | 892 | } |
913f6eb4 | 893 | EXPORT_SYMBOL_GPL(ref_module); |
1da177e4 LT |
894 | |
895 | /* Clear the unload stuff of the module. */ | |
896 | static void module_unload_free(struct module *mod) | |
897 | { | |
2c02dfe7 | 898 | struct module_use *use, *tmp; |
1da177e4 | 899 | |
75676500 | 900 | mutex_lock(&module_mutex); |
2c02dfe7 LT |
901 | list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) { |
902 | struct module *i = use->target; | |
5e124169 | 903 | pr_debug("%s unusing %s\n", mod->name, i->name); |
2c02dfe7 LT |
904 | module_put(i); |
905 | list_del(&use->source_list); | |
906 | list_del(&use->target_list); | |
907 | kfree(use); | |
1da177e4 | 908 | } |
75676500 | 909 | mutex_unlock(&module_mutex); |
1da177e4 LT |
910 | } |
911 | ||
912 | #ifdef CONFIG_MODULE_FORCE_UNLOAD | |
fb169793 | 913 | static inline int try_force_unload(unsigned int flags) |
1da177e4 LT |
914 | { |
915 | int ret = (flags & O_TRUNC); | |
916 | if (ret) | |
373d4d09 | 917 | add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE); |
1da177e4 LT |
918 | return ret; |
919 | } | |
920 | #else | |
fb169793 | 921 | static inline int try_force_unload(unsigned int flags) |
1da177e4 LT |
922 | { |
923 | return 0; | |
924 | } | |
925 | #endif /* CONFIG_MODULE_FORCE_UNLOAD */ | |
926 | ||
e513cc1c MH |
927 | /* Try to release refcount of module, 0 means success. */ |
928 | static int try_release_module_ref(struct module *mod) | |
1da177e4 | 929 | { |
e513cc1c | 930 | int ret; |
1da177e4 | 931 | |
e513cc1c MH |
932 | /* Try to decrement refcnt which we set at loading */ |
933 | ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt); | |
934 | BUG_ON(ret < 0); | |
935 | if (ret) | |
936 | /* Someone can put this right now, recover with checking */ | |
937 | ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0); | |
1da177e4 | 938 | |
e513cc1c MH |
939 | return ret; |
940 | } | |
1da177e4 | 941 | |
e513cc1c MH |
942 | static int try_stop_module(struct module *mod, int flags, int *forced) |
943 | { | |
da39ba5e | 944 | /* If it's not unused, quit unless we're forcing. */ |
e513cc1c MH |
945 | if (try_release_module_ref(mod) != 0) { |
946 | *forced = try_force_unload(flags); | |
947 | if (!(*forced)) | |
1da177e4 LT |
948 | return -EWOULDBLOCK; |
949 | } | |
950 | ||
951 | /* Mark it as dying. */ | |
e513cc1c | 952 | mod->state = MODULE_STATE_GOING; |
1da177e4 | 953 | |
e513cc1c | 954 | return 0; |
1da177e4 LT |
955 | } |
956 | ||
d5db139a RR |
957 | /** |
958 | * module_refcount - return the refcount or -1 if unloading | |
959 | * | |
960 | * @mod: the module we're checking | |
961 | * | |
962 | * Returns: | |
963 | * -1 if the module is in the process of unloading | |
964 | * otherwise the number of references in the kernel to the module | |
965 | */ | |
966 | int module_refcount(struct module *mod) | |
1da177e4 | 967 | { |
d5db139a | 968 | return atomic_read(&mod->refcnt) - MODULE_REF_BASE; |
1da177e4 LT |
969 | } |
970 | EXPORT_SYMBOL(module_refcount); | |
971 | ||
972 | /* This exists whether we can unload or not */ | |
973 | static void free_module(struct module *mod); | |
974 | ||
17da2bd9 HC |
975 | SYSCALL_DEFINE2(delete_module, const char __user *, name_user, |
976 | unsigned int, flags) | |
1da177e4 LT |
977 | { |
978 | struct module *mod; | |
dfff0a06 | 979 | char name[MODULE_NAME_LEN]; |
1da177e4 LT |
980 | int ret, forced = 0; |
981 | ||
3d43321b | 982 | if (!capable(CAP_SYS_MODULE) || modules_disabled) |
dfff0a06 GKH |
983 | return -EPERM; |
984 | ||
985 | if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) | |
986 | return -EFAULT; | |
987 | name[MODULE_NAME_LEN-1] = '\0'; | |
988 | ||
f6276ac9 RGB |
989 | audit_log_kern_module(name); |
990 | ||
3fc1f1e2 TH |
991 | if (mutex_lock_interruptible(&module_mutex) != 0) |
992 | return -EINTR; | |
1da177e4 LT |
993 | |
994 | mod = find_module(name); | |
995 | if (!mod) { | |
996 | ret = -ENOENT; | |
997 | goto out; | |
998 | } | |
999 | ||
2c02dfe7 | 1000 | if (!list_empty(&mod->source_list)) { |
1da177e4 LT |
1001 | /* Other modules depend on us: get rid of them first. */ |
1002 | ret = -EWOULDBLOCK; | |
1003 | goto out; | |
1004 | } | |
1005 | ||
1006 | /* Doing init or already dying? */ | |
1007 | if (mod->state != MODULE_STATE_LIVE) { | |
3f2b9c9c | 1008 | /* FIXME: if (force), slam module count damn the torpedoes */ |
5e124169 | 1009 | pr_debug("%s already dying\n", mod->name); |
1da177e4 LT |
1010 | ret = -EBUSY; |
1011 | goto out; | |
1012 | } | |
1013 | ||
1014 | /* If it has an init func, it must have an exit func to unload */ | |
af49d924 | 1015 | if (mod->init && !mod->exit) { |
fb169793 | 1016 | forced = try_force_unload(flags); |
1da177e4 LT |
1017 | if (!forced) { |
1018 | /* This module can't be removed */ | |
1019 | ret = -EBUSY; | |
1020 | goto out; | |
1021 | } | |
1022 | } | |
1023 | ||
1da177e4 LT |
1024 | /* Stop the machine so refcounts can't move and disable module. */ |
1025 | ret = try_stop_module(mod, flags, &forced); | |
1026 | if (ret != 0) | |
1027 | goto out; | |
1028 | ||
df4b565e | 1029 | mutex_unlock(&module_mutex); |
25985edc | 1030 | /* Final destruction now no one is using it. */ |
df4b565e | 1031 | if (mod->exit != NULL) |
1da177e4 | 1032 | mod->exit(); |
df4b565e PO |
1033 | blocking_notifier_call_chain(&module_notify_list, |
1034 | MODULE_STATE_GOING, mod); | |
7e545d6e | 1035 | klp_module_going(mod); |
7dcd182b JY |
1036 | ftrace_release_mod(mod); |
1037 | ||
22a9d645 | 1038 | async_synchronize_full(); |
75676500 | 1039 | |
e14af7ee | 1040 | /* Store the name of the last unloaded module for diagnostic purposes */ |
efa5345e | 1041 | strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); |
1da177e4 | 1042 | |
75676500 | 1043 | free_module(mod); |
31890801 KK |
1044 | /* someone could wait for the module in add_unformed_module() */ |
1045 | wake_up_all(&module_wq); | |
75676500 RR |
1046 | return 0; |
1047 | out: | |
6389a385 | 1048 | mutex_unlock(&module_mutex); |
1da177e4 LT |
1049 | return ret; |
1050 | } | |
1051 | ||
d1e99d7a | 1052 | static inline void print_unload_info(struct seq_file *m, struct module *mod) |
1da177e4 LT |
1053 | { |
1054 | struct module_use *use; | |
1055 | int printed_something = 0; | |
1056 | ||
d5db139a | 1057 | seq_printf(m, " %i ", module_refcount(mod)); |
1da177e4 | 1058 | |
6da0b565 IA |
1059 | /* |
1060 | * Always include a trailing , so userspace can differentiate | |
1061 | * between this and the old multi-field proc format. | |
1062 | */ | |
2c02dfe7 | 1063 | list_for_each_entry(use, &mod->source_list, source_list) { |
1da177e4 | 1064 | printed_something = 1; |
2c02dfe7 | 1065 | seq_printf(m, "%s,", use->source->name); |
1da177e4 LT |
1066 | } |
1067 | ||
1da177e4 LT |
1068 | if (mod->init != NULL && mod->exit == NULL) { |
1069 | printed_something = 1; | |
6da0b565 | 1070 | seq_puts(m, "[permanent],"); |
1da177e4 LT |
1071 | } |
1072 | ||
1073 | if (!printed_something) | |
6da0b565 | 1074 | seq_puts(m, "-"); |
1da177e4 LT |
1075 | } |
1076 | ||
1077 | void __symbol_put(const char *symbol) | |
1078 | { | |
1079 | struct module *owner; | |
1da177e4 | 1080 | |
24da1cbf | 1081 | preempt_disable(); |
5cb90343 | 1082 | if (!find_symbol(symbol, &owner, NULL, true, false)) |
1da177e4 LT |
1083 | BUG(); |
1084 | module_put(owner); | |
24da1cbf | 1085 | preempt_enable(); |
1da177e4 LT |
1086 | } |
1087 | EXPORT_SYMBOL(__symbol_put); | |
1088 | ||
7d1d16e4 | 1089 | /* Note this assumes addr is a function, which it currently always is. */ |
1da177e4 LT |
1090 | void symbol_put_addr(void *addr) |
1091 | { | |
5e376613 | 1092 | struct module *modaddr; |
7d1d16e4 | 1093 | unsigned long a = (unsigned long)dereference_function_descriptor(addr); |
1da177e4 | 1094 | |
7d1d16e4 | 1095 | if (core_kernel_text(a)) |
5e376613 | 1096 | return; |
1da177e4 | 1097 | |
275d7d44 PZ |
1098 | /* |
1099 | * Even though we hold a reference on the module; we still need to | |
1100 | * disable preemption in order to safely traverse the data structure. | |
1101 | */ | |
1102 | preempt_disable(); | |
7d1d16e4 | 1103 | modaddr = __module_text_address(a); |
a6e6abd5 | 1104 | BUG_ON(!modaddr); |
5e376613 | 1105 | module_put(modaddr); |
275d7d44 | 1106 | preempt_enable(); |
1da177e4 LT |
1107 | } |
1108 | EXPORT_SYMBOL_GPL(symbol_put_addr); | |
1109 | ||
1110 | static ssize_t show_refcnt(struct module_attribute *mattr, | |
4befb026 | 1111 | struct module_kobject *mk, char *buffer) |
1da177e4 | 1112 | { |
d5db139a | 1113 | return sprintf(buffer, "%i\n", module_refcount(mk->mod)); |
1da177e4 LT |
1114 | } |
1115 | ||
cca3e707 KS |
1116 | static struct module_attribute modinfo_refcnt = |
1117 | __ATTR(refcnt, 0444, show_refcnt, NULL); | |
1da177e4 | 1118 | |
d53799be SR |
1119 | void __module_get(struct module *module) |
1120 | { | |
1121 | if (module) { | |
1122 | preempt_disable(); | |
2f35c41f | 1123 | atomic_inc(&module->refcnt); |
d53799be SR |
1124 | trace_module_get(module, _RET_IP_); |
1125 | preempt_enable(); | |
1126 | } | |
1127 | } | |
1128 | EXPORT_SYMBOL(__module_get); | |
1129 | ||
1130 | bool try_module_get(struct module *module) | |
1131 | { | |
1132 | bool ret = true; | |
1133 | ||
1134 | if (module) { | |
1135 | preempt_disable(); | |
e513cc1c MH |
1136 | /* Note: here, we can fail to get a reference */ |
1137 | if (likely(module_is_live(module) && | |
1138 | atomic_inc_not_zero(&module->refcnt) != 0)) | |
d53799be | 1139 | trace_module_get(module, _RET_IP_); |
e513cc1c | 1140 | else |
d53799be SR |
1141 | ret = false; |
1142 | ||
1143 | preempt_enable(); | |
1144 | } | |
1145 | return ret; | |
1146 | } | |
1147 | EXPORT_SYMBOL(try_module_get); | |
1148 | ||
f6a57033 AV |
1149 | void module_put(struct module *module) |
1150 | { | |
e513cc1c MH |
1151 | int ret; |
1152 | ||
f6a57033 | 1153 | if (module) { |
e1783a24 | 1154 | preempt_disable(); |
e513cc1c MH |
1155 | ret = atomic_dec_if_positive(&module->refcnt); |
1156 | WARN_ON(ret < 0); /* Failed to put refcount */ | |
ae832d1e | 1157 | trace_module_put(module, _RET_IP_); |
e1783a24 | 1158 | preempt_enable(); |
f6a57033 AV |
1159 | } |
1160 | } | |
1161 | EXPORT_SYMBOL(module_put); | |
1162 | ||
1da177e4 | 1163 | #else /* !CONFIG_MODULE_UNLOAD */ |
d1e99d7a | 1164 | static inline void print_unload_info(struct seq_file *m, struct module *mod) |
1da177e4 LT |
1165 | { |
1166 | /* We don't know the usage count, or what modules are using. */ | |
6da0b565 | 1167 | seq_puts(m, " - -"); |
1da177e4 LT |
1168 | } |
1169 | ||
1170 | static inline void module_unload_free(struct module *mod) | |
1171 | { | |
1172 | } | |
1173 | ||
913f6eb4 | 1174 | int ref_module(struct module *a, struct module *b) |
1da177e4 | 1175 | { |
9bea7f23 | 1176 | return strong_try_module_get(b); |
1da177e4 | 1177 | } |
913f6eb4 | 1178 | EXPORT_SYMBOL_GPL(ref_module); |
1da177e4 | 1179 | |
9f85a4bb | 1180 | static inline int module_unload_init(struct module *mod) |
1da177e4 | 1181 | { |
9f85a4bb | 1182 | return 0; |
1da177e4 LT |
1183 | } |
1184 | #endif /* CONFIG_MODULE_UNLOAD */ | |
1185 | ||
53999bf3 KW |
1186 | static size_t module_flags_taint(struct module *mod, char *buf) |
1187 | { | |
1188 | size_t l = 0; | |
7fd8329b PM |
1189 | int i; |
1190 | ||
1191 | for (i = 0; i < TAINT_FLAGS_COUNT; i++) { | |
1192 | if (taint_flags[i].module && test_bit(i, &mod->taints)) | |
5eb7c0d0 | 1193 | buf[l++] = taint_flags[i].c_true; |
7fd8329b | 1194 | } |
53999bf3 | 1195 | |
53999bf3 KW |
1196 | return l; |
1197 | } | |
1198 | ||
1f71740a | 1199 | static ssize_t show_initstate(struct module_attribute *mattr, |
4befb026 | 1200 | struct module_kobject *mk, char *buffer) |
1f71740a KS |
1201 | { |
1202 | const char *state = "unknown"; | |
1203 | ||
4befb026 | 1204 | switch (mk->mod->state) { |
1f71740a KS |
1205 | case MODULE_STATE_LIVE: |
1206 | state = "live"; | |
1207 | break; | |
1208 | case MODULE_STATE_COMING: | |
1209 | state = "coming"; | |
1210 | break; | |
1211 | case MODULE_STATE_GOING: | |
1212 | state = "going"; | |
1213 | break; | |
0d21b0e3 RR |
1214 | default: |
1215 | BUG(); | |
1f71740a KS |
1216 | } |
1217 | return sprintf(buffer, "%s\n", state); | |
1218 | } | |
1219 | ||
cca3e707 KS |
1220 | static struct module_attribute modinfo_initstate = |
1221 | __ATTR(initstate, 0444, show_initstate, NULL); | |
1f71740a | 1222 | |
88bfa324 KS |
1223 | static ssize_t store_uevent(struct module_attribute *mattr, |
1224 | struct module_kobject *mk, | |
1225 | const char *buffer, size_t count) | |
1226 | { | |
df44b479 PR |
1227 | int rc; |
1228 | ||
1229 | rc = kobject_synth_uevent(&mk->kobj, buffer, count); | |
1230 | return rc ? rc : count; | |
88bfa324 KS |
1231 | } |
1232 | ||
cca3e707 KS |
1233 | struct module_attribute module_uevent = |
1234 | __ATTR(uevent, 0200, NULL, store_uevent); | |
1235 | ||
1236 | static ssize_t show_coresize(struct module_attribute *mattr, | |
1237 | struct module_kobject *mk, char *buffer) | |
1238 | { | |
7523e4dc | 1239 | return sprintf(buffer, "%u\n", mk->mod->core_layout.size); |
cca3e707 KS |
1240 | } |
1241 | ||
1242 | static struct module_attribute modinfo_coresize = | |
1243 | __ATTR(coresize, 0444, show_coresize, NULL); | |
1244 | ||
1245 | static ssize_t show_initsize(struct module_attribute *mattr, | |
1246 | struct module_kobject *mk, char *buffer) | |
1247 | { | |
7523e4dc | 1248 | return sprintf(buffer, "%u\n", mk->mod->init_layout.size); |
cca3e707 KS |
1249 | } |
1250 | ||
1251 | static struct module_attribute modinfo_initsize = | |
1252 | __ATTR(initsize, 0444, show_initsize, NULL); | |
1253 | ||
1254 | static ssize_t show_taint(struct module_attribute *mattr, | |
1255 | struct module_kobject *mk, char *buffer) | |
1256 | { | |
1257 | size_t l; | |
1258 | ||
1259 | l = module_flags_taint(mk->mod, buffer); | |
1260 | buffer[l++] = '\n'; | |
1261 | return l; | |
1262 | } | |
1263 | ||
1264 | static struct module_attribute modinfo_taint = | |
1265 | __ATTR(taint, 0444, show_taint, NULL); | |
88bfa324 | 1266 | |
03e88ae1 | 1267 | static struct module_attribute *modinfo_attrs[] = { |
cca3e707 | 1268 | &module_uevent, |
03e88ae1 GKH |
1269 | &modinfo_version, |
1270 | &modinfo_srcversion, | |
cca3e707 KS |
1271 | &modinfo_initstate, |
1272 | &modinfo_coresize, | |
1273 | &modinfo_initsize, | |
1274 | &modinfo_taint, | |
03e88ae1 | 1275 | #ifdef CONFIG_MODULE_UNLOAD |
cca3e707 | 1276 | &modinfo_refcnt, |
03e88ae1 GKH |
1277 | #endif |
1278 | NULL, | |
1279 | }; | |
1280 | ||
1da177e4 LT |
1281 | static const char vermagic[] = VERMAGIC_STRING; |
1282 | ||
c6e665c8 | 1283 | static int try_to_force_load(struct module *mod, const char *reason) |
826e4506 LT |
1284 | { |
1285 | #ifdef CONFIG_MODULE_FORCE_LOAD | |
25ddbb18 | 1286 | if (!test_taint(TAINT_FORCED_MODULE)) |
bddb12b3 | 1287 | pr_warn("%s: %s: kernel tainted.\n", mod->name, reason); |
373d4d09 | 1288 | add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE); |
826e4506 LT |
1289 | return 0; |
1290 | #else | |
1291 | return -ENOEXEC; | |
1292 | #endif | |
1293 | } | |
1294 | ||
1da177e4 | 1295 | #ifdef CONFIG_MODVERSIONS |
71810db2 AB |
1296 | |
1297 | static u32 resolve_rel_crc(const s32 *crc) | |
d4703aef | 1298 | { |
71810db2 | 1299 | return *(u32 *)((void *)crc + *crc); |
d4703aef RR |
1300 | } |
1301 | ||
49019426 | 1302 | static int check_version(const struct load_info *info, |
1da177e4 | 1303 | const char *symname, |
6da0b565 | 1304 | struct module *mod, |
71810db2 | 1305 | const s32 *crc) |
1da177e4 | 1306 | { |
49019426 KC |
1307 | Elf_Shdr *sechdrs = info->sechdrs; |
1308 | unsigned int versindex = info->index.vers; | |
1da177e4 LT |
1309 | unsigned int i, num_versions; |
1310 | struct modversion_info *versions; | |
1311 | ||
1312 | /* Exporting module didn't supply crcs? OK, we're already tainted. */ | |
1313 | if (!crc) | |
1314 | return 1; | |
1315 | ||
a5dd6970 RR |
1316 | /* No versions at all? modprobe --force does this. */ |
1317 | if (versindex == 0) | |
1318 | return try_to_force_load(mod, symname) == 0; | |
1319 | ||
1da177e4 LT |
1320 | versions = (void *) sechdrs[versindex].sh_addr; |
1321 | num_versions = sechdrs[versindex].sh_size | |
1322 | / sizeof(struct modversion_info); | |
1323 | ||
1324 | for (i = 0; i < num_versions; i++) { | |
71810db2 AB |
1325 | u32 crcval; |
1326 | ||
1da177e4 LT |
1327 | if (strcmp(versions[i].name, symname) != 0) |
1328 | continue; | |
1329 | ||
71810db2 AB |
1330 | if (IS_ENABLED(CONFIG_MODULE_REL_CRCS)) |
1331 | crcval = resolve_rel_crc(crc); | |
1332 | else | |
1333 | crcval = *crc; | |
1334 | if (versions[i].crc == crcval) | |
1da177e4 | 1335 | return 1; |
71810db2 AB |
1336 | pr_debug("Found checksum %X vs module %lX\n", |
1337 | crcval, versions[i].crc); | |
826e4506 | 1338 | goto bad_version; |
1da177e4 | 1339 | } |
826e4506 | 1340 | |
faaae2a5 | 1341 | /* Broken toolchain. Warn once, then let it go.. */ |
3e2e857f | 1342 | pr_warn_once("%s: no symbol version for %s\n", info->name, symname); |
faaae2a5 | 1343 | return 1; |
826e4506 LT |
1344 | |
1345 | bad_version: | |
6da0b565 | 1346 | pr_warn("%s: disagrees about version of symbol %s\n", |
3e2e857f | 1347 | info->name, symname); |
826e4506 | 1348 | return 0; |
1da177e4 LT |
1349 | } |
1350 | ||
49019426 | 1351 | static inline int check_modstruct_version(const struct load_info *info, |
1da177e4 LT |
1352 | struct module *mod) |
1353 | { | |
71810db2 | 1354 | const s32 *crc; |
1da177e4 | 1355 | |
926a59b1 PZ |
1356 | /* |
1357 | * Since this should be found in kernel (which can't be removed), no | |
1358 | * locking is necessary -- use preempt_disable() to placate lockdep. | |
1359 | */ | |
1360 | preempt_disable(); | |
5cb90343 | 1361 | if (!find_symbol("module_layout", NULL, &crc, true, false)) { |
926a59b1 | 1362 | preempt_enable(); |
1da177e4 | 1363 | BUG(); |
926a59b1 PZ |
1364 | } |
1365 | preempt_enable(); | |
996302c5 | 1366 | return check_version(info, "module_layout", mod, crc); |
1da177e4 LT |
1367 | } |
1368 | ||
91e37a79 RR |
1369 | /* First part is kernel version, which we ignore if module has crcs. */ |
1370 | static inline int same_magic(const char *amagic, const char *bmagic, | |
1371 | bool has_crcs) | |
1da177e4 | 1372 | { |
91e37a79 RR |
1373 | if (has_crcs) { |
1374 | amagic += strcspn(amagic, " "); | |
1375 | bmagic += strcspn(bmagic, " "); | |
1376 | } | |
1da177e4 LT |
1377 | return strcmp(amagic, bmagic) == 0; |
1378 | } | |
1379 | #else | |
49019426 | 1380 | static inline int check_version(const struct load_info *info, |
1da177e4 | 1381 | const char *symname, |
6da0b565 | 1382 | struct module *mod, |
71810db2 | 1383 | const s32 *crc) |
1da177e4 LT |
1384 | { |
1385 | return 1; | |
1386 | } | |
1387 | ||
49019426 | 1388 | static inline int check_modstruct_version(const struct load_info *info, |
1da177e4 LT |
1389 | struct module *mod) |
1390 | { | |
1391 | return 1; | |
1392 | } | |
1393 | ||
91e37a79 RR |
1394 | static inline int same_magic(const char *amagic, const char *bmagic, |
1395 | bool has_crcs) | |
1da177e4 LT |
1396 | { |
1397 | return strcmp(amagic, bmagic) == 0; | |
1398 | } | |
1399 | #endif /* CONFIG_MODVERSIONS */ | |
1400 | ||
8651ec01 MM |
1401 | static char *get_modinfo(const struct load_info *info, const char *tag); |
1402 | static char *get_next_modinfo(const struct load_info *info, const char *tag, | |
1403 | char *prev); | |
1404 | ||
1405 | static int verify_namespace_is_imported(const struct load_info *info, | |
1406 | const struct kernel_symbol *sym, | |
1407 | struct module *mod) | |
1408 | { | |
1409 | const char *namespace; | |
1410 | char *imported_namespace; | |
1411 | ||
1412 | namespace = kernel_symbol_namespace(sym); | |
1413 | if (namespace) { | |
1414 | imported_namespace = get_modinfo(info, "import_ns"); | |
1415 | while (imported_namespace) { | |
1416 | if (strcmp(namespace, imported_namespace) == 0) | |
1417 | return 0; | |
1418 | imported_namespace = get_next_modinfo( | |
1419 | info, "import_ns", imported_namespace); | |
1420 | } | |
3d52ec5e MM |
1421 | #ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS |
1422 | pr_warn( | |
1423 | #else | |
1424 | pr_err( | |
1425 | #endif | |
1426 | "%s: module uses symbol (%s) from namespace %s, but does not import it.\n", | |
1427 | mod->name, kernel_symbol_name(sym), namespace); | |
1428 | #ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS | |
8651ec01 | 1429 | return -EINVAL; |
3d52ec5e | 1430 | #endif |
8651ec01 MM |
1431 | } |
1432 | return 0; | |
1433 | } | |
1434 | ||
1435 | ||
75676500 | 1436 | /* Resolve a symbol for this module. I.e. if we find one, record usage. */ |
49668688 RR |
1437 | static const struct kernel_symbol *resolve_symbol(struct module *mod, |
1438 | const struct load_info *info, | |
414fd31b | 1439 | const char *name, |
9bea7f23 | 1440 | char ownername[]) |
1da177e4 LT |
1441 | { |
1442 | struct module *owner; | |
414fd31b | 1443 | const struct kernel_symbol *sym; |
71810db2 | 1444 | const s32 *crc; |
9bea7f23 | 1445 | int err; |
1da177e4 | 1446 | |
d64810f5 PZ |
1447 | /* |
1448 | * The module_mutex should not be a heavily contended lock; | |
1449 | * if we get the occasional sleep here, we'll go an extra iteration | |
1450 | * in the wait_event_interruptible(), which is harmless. | |
1451 | */ | |
1452 | sched_annotate_sleep(); | |
75676500 | 1453 | mutex_lock(&module_mutex); |
5cb90343 | 1454 | sym = find_symbol(name, &owner, &crc, |
25ddbb18 | 1455 | !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true); |
9bea7f23 RR |
1456 | if (!sym) |
1457 | goto unlock; | |
1458 | ||
49019426 | 1459 | if (!check_version(info, name, mod, crc)) { |
9bea7f23 RR |
1460 | sym = ERR_PTR(-EINVAL); |
1461 | goto getname; | |
1da177e4 | 1462 | } |
9bea7f23 | 1463 | |
8651ec01 MM |
1464 | err = verify_namespace_is_imported(info, sym, mod); |
1465 | if (err) { | |
1466 | sym = ERR_PTR(err); | |
1467 | goto getname; | |
1468 | } | |
1469 | ||
9bea7f23 RR |
1470 | err = ref_module(mod, owner); |
1471 | if (err) { | |
1472 | sym = ERR_PTR(err); | |
1473 | goto getname; | |
1474 | } | |
1475 | ||
1476 | getname: | |
1477 | /* We must make copy under the lock if we failed to get ref. */ | |
1478 | strncpy(ownername, module_name(owner), MODULE_NAME_LEN); | |
1479 | unlock: | |
75676500 | 1480 | mutex_unlock(&module_mutex); |
218ce735 | 1481 | return sym; |
1da177e4 LT |
1482 | } |
1483 | ||
49668688 RR |
1484 | static const struct kernel_symbol * |
1485 | resolve_symbol_wait(struct module *mod, | |
1486 | const struct load_info *info, | |
1487 | const char *name) | |
9bea7f23 RR |
1488 | { |
1489 | const struct kernel_symbol *ksym; | |
49668688 | 1490 | char owner[MODULE_NAME_LEN]; |
9bea7f23 RR |
1491 | |
1492 | if (wait_event_interruptible_timeout(module_wq, | |
49668688 RR |
1493 | !IS_ERR(ksym = resolve_symbol(mod, info, name, owner)) |
1494 | || PTR_ERR(ksym) != -EBUSY, | |
9bea7f23 | 1495 | 30 * HZ) <= 0) { |
bddb12b3 AM |
1496 | pr_warn("%s: gave up waiting for init of module %s.\n", |
1497 | mod->name, owner); | |
9bea7f23 RR |
1498 | } |
1499 | return ksym; | |
1500 | } | |
1501 | ||
1da177e4 LT |
1502 | /* |
1503 | * /sys/module/foo/sections stuff | |
1504 | * J. Corbet <corbet@lwn.net> | |
1505 | */ | |
8f6d0378 | 1506 | #ifdef CONFIG_SYSFS |
10b465aa | 1507 | |
8f6d0378 | 1508 | #ifdef CONFIG_KALLSYMS |
10b465aa BH |
1509 | static inline bool sect_empty(const Elf_Shdr *sect) |
1510 | { | |
1511 | return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0; | |
1512 | } | |
1513 | ||
6da0b565 | 1514 | struct module_sect_attr { |
e64be645 | 1515 | struct bin_attribute battr; |
a58730c4 RR |
1516 | unsigned long address; |
1517 | }; | |
1518 | ||
6da0b565 | 1519 | struct module_sect_attrs { |
a58730c4 RR |
1520 | struct attribute_group grp; |
1521 | unsigned int nsections; | |
1522 | struct module_sect_attr attrs[0]; | |
1523 | }; | |
1524 | ||
c57bfd71 | 1525 | #define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4)) |
e64be645 KC |
1526 | static ssize_t module_sect_read(struct file *file, struct kobject *kobj, |
1527 | struct bin_attribute *battr, | |
1528 | char *buf, loff_t pos, size_t count) | |
1da177e4 LT |
1529 | { |
1530 | struct module_sect_attr *sattr = | |
e64be645 | 1531 | container_of(battr, struct module_sect_attr, battr); |
c57bfd71 KC |
1532 | char bounce[MODULE_SECT_READ_SIZE + 1]; |
1533 | size_t wrote; | |
e64be645 KC |
1534 | |
1535 | if (pos != 0) | |
1536 | return -EINVAL; | |
1537 | ||
c57bfd71 KC |
1538 | /* |
1539 | * Since we're a binary read handler, we must account for the | |
1540 | * trailing NUL byte that sprintf will write: if "buf" is | |
1541 | * too small to hold the NUL, or the NUL is exactly the last | |
1542 | * byte, the read will look like it got truncated by one byte. | |
1543 | * Since there is no way to ask sprintf nicely to not write | |
1544 | * the NUL, we have to use a bounce buffer. | |
1545 | */ | |
1546 | wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n", | |
1547 | kallsyms_show_value(file->f_cred) | |
1548 | ? (void *)sattr->address : NULL); | |
1549 | count = min(count, wrote); | |
1550 | memcpy(buf, bounce, count); | |
1551 | ||
1552 | return count; | |
1da177e4 LT |
1553 | } |
1554 | ||
04b1db9f IN |
1555 | static void free_sect_attrs(struct module_sect_attrs *sect_attrs) |
1556 | { | |
a58730c4 | 1557 | unsigned int section; |
04b1db9f IN |
1558 | |
1559 | for (section = 0; section < sect_attrs->nsections; section++) | |
e64be645 | 1560 | kfree(sect_attrs->attrs[section].battr.attr.name); |
04b1db9f IN |
1561 | kfree(sect_attrs); |
1562 | } | |
1563 | ||
8f6d0378 | 1564 | static void add_sect_attrs(struct module *mod, const struct load_info *info) |
1da177e4 LT |
1565 | { |
1566 | unsigned int nloaded = 0, i, size[2]; | |
1567 | struct module_sect_attrs *sect_attrs; | |
1568 | struct module_sect_attr *sattr; | |
e64be645 | 1569 | struct bin_attribute **gattr; |
22a8bdeb | 1570 | |
1da177e4 | 1571 | /* Count loaded sections and allocate structures */ |
8f6d0378 RR |
1572 | for (i = 0; i < info->hdr->e_shnum; i++) |
1573 | if (!sect_empty(&info->sechdrs[i])) | |
1da177e4 | 1574 | nloaded++; |
8d1b73dd | 1575 | size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded), |
e64be645 KC |
1576 | sizeof(sect_attrs->grp.bin_attrs[0])); |
1577 | size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]); | |
04b1db9f IN |
1578 | sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); |
1579 | if (sect_attrs == NULL) | |
1da177e4 LT |
1580 | return; |
1581 | ||
1582 | /* Setup section attributes. */ | |
1583 | sect_attrs->grp.name = "sections"; | |
e64be645 | 1584 | sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0]; |
1da177e4 | 1585 | |
04b1db9f | 1586 | sect_attrs->nsections = 0; |
1da177e4 | 1587 | sattr = §_attrs->attrs[0]; |
e64be645 | 1588 | gattr = §_attrs->grp.bin_attrs[0]; |
8f6d0378 RR |
1589 | for (i = 0; i < info->hdr->e_shnum; i++) { |
1590 | Elf_Shdr *sec = &info->sechdrs[i]; | |
1591 | if (sect_empty(sec)) | |
35dead42 | 1592 | continue; |
e64be645 | 1593 | sysfs_bin_attr_init(&sattr->battr); |
8f6d0378 | 1594 | sattr->address = sec->sh_addr; |
e64be645 KC |
1595 | sattr->battr.attr.name = |
1596 | kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL); | |
1597 | if (sattr->battr.attr.name == NULL) | |
04b1db9f IN |
1598 | goto out; |
1599 | sect_attrs->nsections++; | |
e64be645 | 1600 | sattr->battr.read = module_sect_read; |
c57bfd71 | 1601 | sattr->battr.size = MODULE_SECT_READ_SIZE; |
e64be645 KC |
1602 | sattr->battr.attr.mode = 0400; |
1603 | *(gattr++) = &(sattr++)->battr; | |
1da177e4 LT |
1604 | } |
1605 | *gattr = NULL; | |
1606 | ||
1607 | if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) | |
1608 | goto out; | |
1609 | ||
1610 | mod->sect_attrs = sect_attrs; | |
1611 | return; | |
1612 | out: | |
04b1db9f | 1613 | free_sect_attrs(sect_attrs); |
1da177e4 LT |
1614 | } |
1615 | ||
1616 | static void remove_sect_attrs(struct module *mod) | |
1617 | { | |
1618 | if (mod->sect_attrs) { | |
1619 | sysfs_remove_group(&mod->mkobj.kobj, | |
1620 | &mod->sect_attrs->grp); | |
1621 | /* We are positive that no one is using any sect attrs | |
1622 | * at this point. Deallocate immediately. */ | |
04b1db9f | 1623 | free_sect_attrs(mod->sect_attrs); |
1da177e4 LT |
1624 | mod->sect_attrs = NULL; |
1625 | } | |
1626 | } | |
1627 | ||
6d760133 RM |
1628 | /* |
1629 | * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. | |
1630 | */ | |
1631 | ||
1632 | struct module_notes_attrs { | |
1633 | struct kobject *dir; | |
1634 | unsigned int notes; | |
1635 | struct bin_attribute attrs[0]; | |
1636 | }; | |
1637 | ||
2c3c8bea | 1638 | static ssize_t module_notes_read(struct file *filp, struct kobject *kobj, |
6d760133 RM |
1639 | struct bin_attribute *bin_attr, |
1640 | char *buf, loff_t pos, size_t count) | |
1641 | { | |
1642 | /* | |
1643 | * The caller checked the pos and count against our size. | |
1644 | */ | |
1645 | memcpy(buf, bin_attr->private + pos, count); | |
1646 | return count; | |
1647 | } | |
1648 | ||
1649 | static void free_notes_attrs(struct module_notes_attrs *notes_attrs, | |
1650 | unsigned int i) | |
1651 | { | |
1652 | if (notes_attrs->dir) { | |
1653 | while (i-- > 0) | |
1654 | sysfs_remove_bin_file(notes_attrs->dir, | |
1655 | ¬es_attrs->attrs[i]); | |
e9432093 | 1656 | kobject_put(notes_attrs->dir); |
6d760133 RM |
1657 | } |
1658 | kfree(notes_attrs); | |
1659 | } | |
1660 | ||
8f6d0378 | 1661 | static void add_notes_attrs(struct module *mod, const struct load_info *info) |
6d760133 RM |
1662 | { |
1663 | unsigned int notes, loaded, i; | |
1664 | struct module_notes_attrs *notes_attrs; | |
1665 | struct bin_attribute *nattr; | |
1666 | ||
ea6bff36 IM |
1667 | /* failed to create section attributes, so can't create notes */ |
1668 | if (!mod->sect_attrs) | |
1669 | return; | |
1670 | ||
6d760133 RM |
1671 | /* Count notes sections and allocate structures. */ |
1672 | notes = 0; | |
8f6d0378 RR |
1673 | for (i = 0; i < info->hdr->e_shnum; i++) |
1674 | if (!sect_empty(&info->sechdrs[i]) && | |
1675 | (info->sechdrs[i].sh_type == SHT_NOTE)) | |
6d760133 RM |
1676 | ++notes; |
1677 | ||
1678 | if (notes == 0) | |
1679 | return; | |
1680 | ||
acafe7e3 | 1681 | notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes), |
6d760133 RM |
1682 | GFP_KERNEL); |
1683 | if (notes_attrs == NULL) | |
1684 | return; | |
1685 | ||
1686 | notes_attrs->notes = notes; | |
1687 | nattr = ¬es_attrs->attrs[0]; | |
8f6d0378 RR |
1688 | for (loaded = i = 0; i < info->hdr->e_shnum; ++i) { |
1689 | if (sect_empty(&info->sechdrs[i])) | |
6d760133 | 1690 | continue; |
8f6d0378 | 1691 | if (info->sechdrs[i].sh_type == SHT_NOTE) { |
361795b1 | 1692 | sysfs_bin_attr_init(nattr); |
e64be645 | 1693 | nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name; |
6d760133 | 1694 | nattr->attr.mode = S_IRUGO; |
8f6d0378 RR |
1695 | nattr->size = info->sechdrs[i].sh_size; |
1696 | nattr->private = (void *) info->sechdrs[i].sh_addr; | |
6d760133 RM |
1697 | nattr->read = module_notes_read; |
1698 | ++nattr; | |
1699 | } | |
1700 | ++loaded; | |
1701 | } | |
1702 | ||
4ff6abff | 1703 | notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); |
6d760133 RM |
1704 | if (!notes_attrs->dir) |
1705 | goto out; | |
1706 | ||
1707 | for (i = 0; i < notes; ++i) | |
1708 | if (sysfs_create_bin_file(notes_attrs->dir, | |
1709 | ¬es_attrs->attrs[i])) | |
1710 | goto out; | |
1711 | ||
1712 | mod->notes_attrs = notes_attrs; | |
1713 | return; | |
1714 | ||
1715 | out: | |
1716 | free_notes_attrs(notes_attrs, i); | |
1717 | } | |
1718 | ||
1719 | static void remove_notes_attrs(struct module *mod) | |
1720 | { | |
1721 | if (mod->notes_attrs) | |
1722 | free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); | |
1723 | } | |
1724 | ||
1da177e4 | 1725 | #else |
04b1db9f | 1726 | |
8f6d0378 RR |
1727 | static inline void add_sect_attrs(struct module *mod, |
1728 | const struct load_info *info) | |
1da177e4 LT |
1729 | { |
1730 | } | |
1731 | ||
1732 | static inline void remove_sect_attrs(struct module *mod) | |
1733 | { | |
1734 | } | |
6d760133 | 1735 | |
8f6d0378 RR |
1736 | static inline void add_notes_attrs(struct module *mod, |
1737 | const struct load_info *info) | |
6d760133 RM |
1738 | { |
1739 | } | |
1740 | ||
1741 | static inline void remove_notes_attrs(struct module *mod) | |
1742 | { | |
1743 | } | |
8f6d0378 | 1744 | #endif /* CONFIG_KALLSYMS */ |
1da177e4 | 1745 | |
1ba5c08b | 1746 | static void del_usage_links(struct module *mod) |
80a3d1bb RR |
1747 | { |
1748 | #ifdef CONFIG_MODULE_UNLOAD | |
1749 | struct module_use *use; | |
80a3d1bb | 1750 | |
75676500 | 1751 | mutex_lock(&module_mutex); |
1ba5c08b CL |
1752 | list_for_each_entry(use, &mod->target_list, target_list) |
1753 | sysfs_remove_link(use->target->holders_dir, mod->name); | |
75676500 | 1754 | mutex_unlock(&module_mutex); |
80a3d1bb RR |
1755 | #endif |
1756 | } | |
1757 | ||
1ba5c08b | 1758 | static int add_usage_links(struct module *mod) |
80a3d1bb | 1759 | { |
1ba5c08b | 1760 | int ret = 0; |
80a3d1bb RR |
1761 | #ifdef CONFIG_MODULE_UNLOAD |
1762 | struct module_use *use; | |
1763 | ||
75676500 | 1764 | mutex_lock(&module_mutex); |
1ba5c08b CL |
1765 | list_for_each_entry(use, &mod->target_list, target_list) { |
1766 | ret = sysfs_create_link(use->target->holders_dir, | |
1767 | &mod->mkobj.kobj, mod->name); | |
1768 | if (ret) | |
1769 | break; | |
1770 | } | |
75676500 | 1771 | mutex_unlock(&module_mutex); |
1ba5c08b CL |
1772 | if (ret) |
1773 | del_usage_links(mod); | |
80a3d1bb | 1774 | #endif |
1ba5c08b | 1775 | return ret; |
80a3d1bb RR |
1776 | } |
1777 | ||
bc6f2a75 Y |
1778 | static void module_remove_modinfo_attrs(struct module *mod, int end); |
1779 | ||
6407ebb2 | 1780 | static int module_add_modinfo_attrs(struct module *mod) |
c988d2b2 MD |
1781 | { |
1782 | struct module_attribute *attr; | |
03e88ae1 | 1783 | struct module_attribute *temp_attr; |
c988d2b2 MD |
1784 | int error = 0; |
1785 | int i; | |
1786 | ||
03e88ae1 GKH |
1787 | mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * |
1788 | (ARRAY_SIZE(modinfo_attrs) + 1)), | |
1789 | GFP_KERNEL); | |
1790 | if (!mod->modinfo_attrs) | |
1791 | return -ENOMEM; | |
1792 | ||
1793 | temp_attr = mod->modinfo_attrs; | |
bc6f2a75 | 1794 | for (i = 0; (attr = modinfo_attrs[i]); i++) { |
c75b590d | 1795 | if (!attr->test || attr->test(mod)) { |
03e88ae1 | 1796 | memcpy(temp_attr, attr, sizeof(*temp_attr)); |
361795b1 | 1797 | sysfs_attr_init(&temp_attr->attr); |
6da0b565 IA |
1798 | error = sysfs_create_file(&mod->mkobj.kobj, |
1799 | &temp_attr->attr); | |
bc6f2a75 Y |
1800 | if (error) |
1801 | goto error_out; | |
03e88ae1 GKH |
1802 | ++temp_attr; |
1803 | } | |
c988d2b2 | 1804 | } |
bc6f2a75 Y |
1805 | |
1806 | return 0; | |
1807 | ||
1808 | error_out: | |
1809 | if (i > 0) | |
1810 | module_remove_modinfo_attrs(mod, --i); | |
635dac08 Y |
1811 | else |
1812 | kfree(mod->modinfo_attrs); | |
c988d2b2 MD |
1813 | return error; |
1814 | } | |
1815 | ||
bc6f2a75 | 1816 | static void module_remove_modinfo_attrs(struct module *mod, int end) |
c988d2b2 MD |
1817 | { |
1818 | struct module_attribute *attr; | |
1819 | int i; | |
1820 | ||
03e88ae1 | 1821 | for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { |
bc6f2a75 Y |
1822 | if (end >= 0 && i > end) |
1823 | break; | |
03e88ae1 GKH |
1824 | /* pick a field to test for end of list */ |
1825 | if (!attr->attr.name) | |
1826 | break; | |
6da0b565 | 1827 | sysfs_remove_file(&mod->mkobj.kobj, &attr->attr); |
03e88ae1 GKH |
1828 | if (attr->free) |
1829 | attr->free(mod); | |
c988d2b2 | 1830 | } |
03e88ae1 | 1831 | kfree(mod->modinfo_attrs); |
c988d2b2 | 1832 | } |
1da177e4 | 1833 | |
942e4431 LZ |
1834 | static void mod_kobject_put(struct module *mod) |
1835 | { | |
1836 | DECLARE_COMPLETION_ONSTACK(c); | |
1837 | mod->mkobj.kobj_completion = &c; | |
1838 | kobject_put(&mod->mkobj.kobj); | |
1839 | wait_for_completion(&c); | |
1840 | } | |
1841 | ||
6407ebb2 | 1842 | static int mod_sysfs_init(struct module *mod) |
1da177e4 LT |
1843 | { |
1844 | int err; | |
6494a93d | 1845 | struct kobject *kobj; |
1da177e4 | 1846 | |
823bccfc | 1847 | if (!module_sysfs_initialized) { |
bddb12b3 | 1848 | pr_err("%s: module sysfs not initialized\n", mod->name); |
1cc5f714 ES |
1849 | err = -EINVAL; |
1850 | goto out; | |
1851 | } | |
6494a93d GKH |
1852 | |
1853 | kobj = kset_find_obj(module_kset, mod->name); | |
1854 | if (kobj) { | |
bddb12b3 | 1855 | pr_err("%s: module is already loaded\n", mod->name); |
6494a93d GKH |
1856 | kobject_put(kobj); |
1857 | err = -EINVAL; | |
1858 | goto out; | |
1859 | } | |
1860 | ||
1da177e4 | 1861 | mod->mkobj.mod = mod; |
e17e0f51 | 1862 | |
ac3c8141 GKH |
1863 | memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); |
1864 | mod->mkobj.kobj.kset = module_kset; | |
1865 | err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, | |
1866 | "%s", mod->name); | |
1867 | if (err) | |
942e4431 | 1868 | mod_kobject_put(mod); |
270a6c4c KS |
1869 | |
1870 | out: | |
1871 | return err; | |
1872 | } | |
1873 | ||
6407ebb2 | 1874 | static int mod_sysfs_setup(struct module *mod, |
8f6d0378 | 1875 | const struct load_info *info, |
270a6c4c KS |
1876 | struct kernel_param *kparam, |
1877 | unsigned int num_params) | |
1878 | { | |
1879 | int err; | |
1880 | ||
80a3d1bb RR |
1881 | err = mod_sysfs_init(mod); |
1882 | if (err) | |
1883 | goto out; | |
1884 | ||
4ff6abff | 1885 | mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); |
240936e1 AM |
1886 | if (!mod->holders_dir) { |
1887 | err = -ENOMEM; | |
270a6c4c | 1888 | goto out_unreg; |
240936e1 | 1889 | } |
270a6c4c | 1890 | |
1da177e4 LT |
1891 | err = module_param_sysfs_setup(mod, kparam, num_params); |
1892 | if (err) | |
270a6c4c | 1893 | goto out_unreg_holders; |
1da177e4 | 1894 | |
c988d2b2 MD |
1895 | err = module_add_modinfo_attrs(mod); |
1896 | if (err) | |
e17e0f51 | 1897 | goto out_unreg_param; |
c988d2b2 | 1898 | |
1ba5c08b CL |
1899 | err = add_usage_links(mod); |
1900 | if (err) | |
1901 | goto out_unreg_modinfo_attrs; | |
1902 | ||
8f6d0378 RR |
1903 | add_sect_attrs(mod, info); |
1904 | add_notes_attrs(mod, info); | |
80a3d1bb | 1905 | |
1da177e4 LT |
1906 | return 0; |
1907 | ||
1ba5c08b | 1908 | out_unreg_modinfo_attrs: |
bc6f2a75 | 1909 | module_remove_modinfo_attrs(mod, -1); |
e17e0f51 KS |
1910 | out_unreg_param: |
1911 | module_param_sysfs_remove(mod); | |
270a6c4c | 1912 | out_unreg_holders: |
78a2d906 | 1913 | kobject_put(mod->holders_dir); |
270a6c4c | 1914 | out_unreg: |
942e4431 | 1915 | mod_kobject_put(mod); |
80a3d1bb | 1916 | out: |
1da177e4 LT |
1917 | return err; |
1918 | } | |
34e4e2fe DL |
1919 | |
1920 | static void mod_sysfs_fini(struct module *mod) | |
1921 | { | |
8f6d0378 RR |
1922 | remove_notes_attrs(mod); |
1923 | remove_sect_attrs(mod); | |
942e4431 | 1924 | mod_kobject_put(mod); |
34e4e2fe DL |
1925 | } |
1926 | ||
cf2fde7b RR |
1927 | static void init_param_lock(struct module *mod) |
1928 | { | |
1929 | mutex_init(&mod->param_lock); | |
1930 | } | |
8f6d0378 | 1931 | #else /* !CONFIG_SYSFS */ |
34e4e2fe | 1932 | |
8f6d0378 RR |
1933 | static int mod_sysfs_setup(struct module *mod, |
1934 | const struct load_info *info, | |
6407ebb2 RR |
1935 | struct kernel_param *kparam, |
1936 | unsigned int num_params) | |
1937 | { | |
1938 | return 0; | |
1939 | } | |
1940 | ||
34e4e2fe DL |
1941 | static void mod_sysfs_fini(struct module *mod) |
1942 | { | |
1943 | } | |
1944 | ||
bc6f2a75 | 1945 | static void module_remove_modinfo_attrs(struct module *mod, int end) |
36b0360d RR |
1946 | { |
1947 | } | |
1948 | ||
80a3d1bb RR |
1949 | static void del_usage_links(struct module *mod) |
1950 | { | |
1951 | } | |
1952 | ||
cf2fde7b RR |
1953 | static void init_param_lock(struct module *mod) |
1954 | { | |
1955 | } | |
34e4e2fe | 1956 | #endif /* CONFIG_SYSFS */ |
1da177e4 | 1957 | |
36b0360d | 1958 | static void mod_sysfs_teardown(struct module *mod) |
1da177e4 | 1959 | { |
80a3d1bb | 1960 | del_usage_links(mod); |
bc6f2a75 | 1961 | module_remove_modinfo_attrs(mod, -1); |
1da177e4 | 1962 | module_param_sysfs_remove(mod); |
78a2d906 GKH |
1963 | kobject_put(mod->mkobj.drivers_dir); |
1964 | kobject_put(mod->holders_dir); | |
34e4e2fe | 1965 | mod_sysfs_fini(mod); |
1da177e4 LT |
1966 | } |
1967 | ||
93651f80 | 1968 | #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX |
84e1c6bb MC |
1969 | /* |
1970 | * LKM RO/NX protection: protect module's text/ro-data | |
1971 | * from modification and any data from execution. | |
85c898db RR |
1972 | * |
1973 | * General layout of module is: | |
444d13ff JY |
1974 | * [text] [read-only-data] [ro-after-init] [writable data] |
1975 | * text_size -----^ ^ ^ ^ | |
1976 | * ro_size ------------------------| | | | |
1977 | * ro_after_init_size -----------------------------| | | |
1978 | * size -----------------------------------------------------------| | |
85c898db RR |
1979 | * |
1980 | * These values are always page-aligned (as is base) | |
84e1c6bb | 1981 | */ |
85c898db RR |
1982 | static void frob_text(const struct module_layout *layout, |
1983 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 1984 | { |
85c898db RR |
1985 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
1986 | BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1)); | |
1987 | set_memory((unsigned long)layout->base, | |
1988 | layout->text_size >> PAGE_SHIFT); | |
84e1c6bb | 1989 | } |
84e1c6bb | 1990 | |
93651f80 | 1991 | #ifdef CONFIG_STRICT_MODULE_RWX |
85c898db RR |
1992 | static void frob_rodata(const struct module_layout *layout, |
1993 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 1994 | { |
85c898db RR |
1995 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
1996 | BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1)); | |
1997 | BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1)); | |
1998 | set_memory((unsigned long)layout->base + layout->text_size, | |
1999 | (layout->ro_size - layout->text_size) >> PAGE_SHIFT); | |
84e1c6bb MC |
2000 | } |
2001 | ||
444d13ff JY |
2002 | static void frob_ro_after_init(const struct module_layout *layout, |
2003 | int (*set_memory)(unsigned long start, int num_pages)) | |
2004 | { | |
2005 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); | |
2006 | BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1)); | |
2007 | BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1)); | |
2008 | set_memory((unsigned long)layout->base + layout->ro_size, | |
2009 | (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT); | |
2010 | } | |
2011 | ||
85c898db RR |
2012 | static void frob_writable_data(const struct module_layout *layout, |
2013 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 2014 | { |
85c898db | 2015 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
444d13ff | 2016 | BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1)); |
85c898db | 2017 | BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1)); |
444d13ff JY |
2018 | set_memory((unsigned long)layout->base + layout->ro_after_init_size, |
2019 | (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT); | |
84e1c6bb | 2020 | } |
84e1c6bb | 2021 | |
85c898db RR |
2022 | /* livepatching wants to disable read-only so it can frob module. */ |
2023 | void module_disable_ro(const struct module *mod) | |
20ef10c1 | 2024 | { |
39290b38 AT |
2025 | if (!rodata_enabled) |
2026 | return; | |
2027 | ||
85c898db RR |
2028 | frob_text(&mod->core_layout, set_memory_rw); |
2029 | frob_rodata(&mod->core_layout, set_memory_rw); | |
444d13ff | 2030 | frob_ro_after_init(&mod->core_layout, set_memory_rw); |
85c898db RR |
2031 | frob_text(&mod->init_layout, set_memory_rw); |
2032 | frob_rodata(&mod->init_layout, set_memory_rw); | |
20ef10c1 | 2033 | } |
84e1c6bb | 2034 | |
444d13ff | 2035 | void module_enable_ro(const struct module *mod, bool after_init) |
01526ed0 | 2036 | { |
39290b38 AT |
2037 | if (!rodata_enabled) |
2038 | return; | |
2039 | ||
1a7b7d92 RE |
2040 | set_vm_flush_reset_perms(mod->core_layout.base); |
2041 | set_vm_flush_reset_perms(mod->init_layout.base); | |
85c898db | 2042 | frob_text(&mod->core_layout, set_memory_ro); |
f2c65fb3 | 2043 | |
85c898db RR |
2044 | frob_rodata(&mod->core_layout, set_memory_ro); |
2045 | frob_text(&mod->init_layout, set_memory_ro); | |
2046 | frob_rodata(&mod->init_layout, set_memory_ro); | |
444d13ff JY |
2047 | |
2048 | if (after_init) | |
2049 | frob_ro_after_init(&mod->core_layout, set_memory_ro); | |
84e1c6bb MC |
2050 | } |
2051 | ||
85c898db | 2052 | static void module_enable_nx(const struct module *mod) |
01526ed0 | 2053 | { |
85c898db | 2054 | frob_rodata(&mod->core_layout, set_memory_nx); |
444d13ff | 2055 | frob_ro_after_init(&mod->core_layout, set_memory_nx); |
85c898db RR |
2056 | frob_writable_data(&mod->core_layout, set_memory_nx); |
2057 | frob_rodata(&mod->init_layout, set_memory_nx); | |
2058 | frob_writable_data(&mod->init_layout, set_memory_nx); | |
01526ed0 JG |
2059 | } |
2060 | ||
84e1c6bb | 2061 | /* Iterate through all modules and set each module's text as RW */ |
5d05c708 | 2062 | void set_all_modules_text_rw(void) |
84e1c6bb MC |
2063 | { |
2064 | struct module *mod; | |
2065 | ||
39290b38 AT |
2066 | if (!rodata_enabled) |
2067 | return; | |
2068 | ||
84e1c6bb MC |
2069 | mutex_lock(&module_mutex); |
2070 | list_for_each_entry_rcu(mod, &modules, list) { | |
0d21b0e3 RR |
2071 | if (mod->state == MODULE_STATE_UNFORMED) |
2072 | continue; | |
85c898db RR |
2073 | |
2074 | frob_text(&mod->core_layout, set_memory_rw); | |
2075 | frob_text(&mod->init_layout, set_memory_rw); | |
84e1c6bb MC |
2076 | } |
2077 | mutex_unlock(&module_mutex); | |
2078 | } | |
2079 | ||
2080 | /* Iterate through all modules and set each module's text as RO */ | |
5d05c708 | 2081 | void set_all_modules_text_ro(void) |
84e1c6bb MC |
2082 | { |
2083 | struct module *mod; | |
2084 | ||
39290b38 AT |
2085 | if (!rodata_enabled) |
2086 | return; | |
2087 | ||
84e1c6bb MC |
2088 | mutex_lock(&module_mutex); |
2089 | list_for_each_entry_rcu(mod, &modules, list) { | |
905dd707 AT |
2090 | /* |
2091 | * Ignore going modules since it's possible that ro | |
2092 | * protection has already been disabled, otherwise we'll | |
2093 | * run into protection faults at module deallocation. | |
2094 | */ | |
2095 | if (mod->state == MODULE_STATE_UNFORMED || | |
2096 | mod->state == MODULE_STATE_GOING) | |
0d21b0e3 | 2097 | continue; |
85c898db RR |
2098 | |
2099 | frob_text(&mod->core_layout, set_memory_ro); | |
2100 | frob_text(&mod->init_layout, set_memory_ro); | |
84e1c6bb MC |
2101 | } |
2102 | mutex_unlock(&module_mutex); | |
2103 | } | |
93651f80 | 2104 | #else /* !CONFIG_STRICT_MODULE_RWX */ |
85c898db | 2105 | static void module_enable_nx(const struct module *mod) { } |
93651f80 | 2106 | #endif /* CONFIG_STRICT_MODULE_RWX */ |
2eef1399 YY |
2107 | static void module_enable_x(const struct module *mod) |
2108 | { | |
2109 | frob_text(&mod->core_layout, set_memory_x); | |
2110 | frob_text(&mod->init_layout, set_memory_x); | |
2111 | } | |
93651f80 YY |
2112 | #else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */ |
2113 | static void module_enable_nx(const struct module *mod) { } | |
2114 | static void module_enable_x(const struct module *mod) { } | |
2115 | #endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */ | |
2116 | ||
84e1c6bb | 2117 | |
1ce15ef4 JY |
2118 | #ifdef CONFIG_LIVEPATCH |
2119 | /* | |
2120 | * Persist Elf information about a module. Copy the Elf header, | |
2121 | * section header table, section string table, and symtab section | |
2122 | * index from info to mod->klp_info. | |
2123 | */ | |
2124 | static int copy_module_elf(struct module *mod, struct load_info *info) | |
2125 | { | |
2126 | unsigned int size, symndx; | |
2127 | int ret; | |
2128 | ||
2129 | size = sizeof(*mod->klp_info); | |
2130 | mod->klp_info = kmalloc(size, GFP_KERNEL); | |
2131 | if (mod->klp_info == NULL) | |
2132 | return -ENOMEM; | |
2133 | ||
2134 | /* Elf header */ | |
2135 | size = sizeof(mod->klp_info->hdr); | |
2136 | memcpy(&mod->klp_info->hdr, info->hdr, size); | |
2137 | ||
2138 | /* Elf section header table */ | |
2139 | size = sizeof(*info->sechdrs) * info->hdr->e_shnum; | |
9be936f4 | 2140 | mod->klp_info->sechdrs = kmemdup(info->sechdrs, size, GFP_KERNEL); |
1ce15ef4 JY |
2141 | if (mod->klp_info->sechdrs == NULL) { |
2142 | ret = -ENOMEM; | |
2143 | goto free_info; | |
2144 | } | |
1ce15ef4 JY |
2145 | |
2146 | /* Elf section name string table */ | |
2147 | size = info->sechdrs[info->hdr->e_shstrndx].sh_size; | |
9be936f4 | 2148 | mod->klp_info->secstrings = kmemdup(info->secstrings, size, GFP_KERNEL); |
1ce15ef4 JY |
2149 | if (mod->klp_info->secstrings == NULL) { |
2150 | ret = -ENOMEM; | |
2151 | goto free_sechdrs; | |
2152 | } | |
1ce15ef4 JY |
2153 | |
2154 | /* Elf symbol section index */ | |
2155 | symndx = info->index.sym; | |
2156 | mod->klp_info->symndx = symndx; | |
2157 | ||
2158 | /* | |
2159 | * For livepatch modules, core_kallsyms.symtab is a complete | |
2160 | * copy of the original symbol table. Adjust sh_addr to point | |
2161 | * to core_kallsyms.symtab since the copy of the symtab in module | |
2162 | * init memory is freed at the end of do_init_module(). | |
2163 | */ | |
2164 | mod->klp_info->sechdrs[symndx].sh_addr = \ | |
2165 | (unsigned long) mod->core_kallsyms.symtab; | |
2166 | ||
2167 | return 0; | |
2168 | ||
2169 | free_sechdrs: | |
2170 | kfree(mod->klp_info->sechdrs); | |
2171 | free_info: | |
2172 | kfree(mod->klp_info); | |
2173 | return ret; | |
2174 | } | |
2175 | ||
2176 | static void free_module_elf(struct module *mod) | |
2177 | { | |
2178 | kfree(mod->klp_info->sechdrs); | |
2179 | kfree(mod->klp_info->secstrings); | |
2180 | kfree(mod->klp_info); | |
2181 | } | |
2182 | #else /* !CONFIG_LIVEPATCH */ | |
2183 | static int copy_module_elf(struct module *mod, struct load_info *info) | |
2184 | { | |
2185 | return 0; | |
2186 | } | |
2187 | ||
2188 | static void free_module_elf(struct module *mod) | |
2189 | { | |
2190 | } | |
2191 | #endif /* CONFIG_LIVEPATCH */ | |
2192 | ||
be1f221c | 2193 | void __weak module_memfree(void *module_region) |
74e08fcf | 2194 | { |
1a7b7d92 RE |
2195 | /* |
2196 | * This memory may be RO, and freeing RO memory in an interrupt is not | |
2197 | * supported by vmalloc. | |
2198 | */ | |
2199 | WARN_ON(in_interrupt()); | |
74e08fcf JB |
2200 | vfree(module_region); |
2201 | } | |
2202 | ||
2203 | void __weak module_arch_cleanup(struct module *mod) | |
2204 | { | |
2205 | } | |
2206 | ||
d453cded RR |
2207 | void __weak module_arch_freeing_init(struct module *mod) |
2208 | { | |
2209 | } | |
2210 | ||
75676500 | 2211 | /* Free a module, remove from lists, etc. */ |
1da177e4 LT |
2212 | static void free_module(struct module *mod) |
2213 | { | |
7ead8b83 LZ |
2214 | trace_module_free(mod); |
2215 | ||
36b0360d | 2216 | mod_sysfs_teardown(mod); |
1da177e4 | 2217 | |
944a1fa0 RR |
2218 | /* We leave it in list to prevent duplicate loads, but make sure |
2219 | * that noone uses it while it's being deconstructed. */ | |
d3051b48 | 2220 | mutex_lock(&module_mutex); |
944a1fa0 | 2221 | mod->state = MODULE_STATE_UNFORMED; |
d3051b48 | 2222 | mutex_unlock(&module_mutex); |
944a1fa0 | 2223 | |
b82bab4b JB |
2224 | /* Remove dynamic debug info */ |
2225 | ddebug_remove_module(mod->name); | |
2226 | ||
1da177e4 LT |
2227 | /* Arch-specific cleanup. */ |
2228 | module_arch_cleanup(mod); | |
2229 | ||
2230 | /* Module unload stuff */ | |
2231 | module_unload_free(mod); | |
2232 | ||
e180a6b7 RR |
2233 | /* Free any allocated parameters. */ |
2234 | destroy_params(mod->kp, mod->num_kp); | |
2235 | ||
1ce15ef4 JY |
2236 | if (is_livepatch_module(mod)) |
2237 | free_module_elf(mod); | |
2238 | ||
944a1fa0 RR |
2239 | /* Now we can delete it from the lists */ |
2240 | mutex_lock(&module_mutex); | |
461e34ae MH |
2241 | /* Unlink carefully: kallsyms could be walking list. */ |
2242 | list_del_rcu(&mod->list); | |
93c2e105 | 2243 | mod_tree_remove(mod); |
0286b5ea | 2244 | /* Remove this module from bug list, this uses list_del_rcu */ |
461e34ae | 2245 | module_bug_cleanup(mod); |
0be964be | 2246 | /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */ |
cb2f5536 | 2247 | synchronize_rcu(); |
944a1fa0 RR |
2248 | mutex_unlock(&module_mutex); |
2249 | ||
85c898db | 2250 | /* This may be empty, but that's OK */ |
d453cded | 2251 | module_arch_freeing_init(mod); |
7523e4dc | 2252 | module_memfree(mod->init_layout.base); |
1da177e4 | 2253 | kfree(mod->args); |
259354de | 2254 | percpu_modfree(mod); |
9f85a4bb | 2255 | |
35a9393c | 2256 | /* Free lock-classes; relies on the preceding sync_rcu(). */ |
7523e4dc | 2257 | lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size); |
fbb9ce95 | 2258 | |
1da177e4 | 2259 | /* Finally, free the core (containing the module structure) */ |
7523e4dc | 2260 | module_memfree(mod->core_layout.base); |
1da177e4 LT |
2261 | } |
2262 | ||
2263 | void *__symbol_get(const char *symbol) | |
2264 | { | |
2265 | struct module *owner; | |
414fd31b | 2266 | const struct kernel_symbol *sym; |
1da177e4 | 2267 | |
24da1cbf | 2268 | preempt_disable(); |
5cb90343 | 2269 | sym = find_symbol(symbol, &owner, NULL, true, true); |
414fd31b TA |
2270 | if (sym && strong_try_module_get(owner)) |
2271 | sym = NULL; | |
24da1cbf | 2272 | preempt_enable(); |
1da177e4 | 2273 | |
7290d580 | 2274 | return sym ? (void *)kernel_symbol_value(sym) : NULL; |
1da177e4 LT |
2275 | } |
2276 | EXPORT_SYMBOL_GPL(__symbol_get); | |
2277 | ||
eea8b54d AN |
2278 | /* |
2279 | * Ensure that an exported symbol [global namespace] does not already exist | |
02a3e59a | 2280 | * in the kernel or in some other module's exported symbol table. |
be593f4c RR |
2281 | * |
2282 | * You must hold the module_mutex. | |
eea8b54d | 2283 | */ |
2d25bc55 | 2284 | static int verify_exported_symbols(struct module *mod) |
eea8b54d | 2285 | { |
b211104d | 2286 | unsigned int i; |
eea8b54d | 2287 | struct module *owner; |
b211104d RR |
2288 | const struct kernel_symbol *s; |
2289 | struct { | |
2290 | const struct kernel_symbol *sym; | |
2291 | unsigned int num; | |
2292 | } arr[] = { | |
2293 | { mod->syms, mod->num_syms }, | |
2294 | { mod->gpl_syms, mod->num_gpl_syms }, | |
2295 | { mod->gpl_future_syms, mod->num_gpl_future_syms }, | |
f7f5b675 | 2296 | #ifdef CONFIG_UNUSED_SYMBOLS |
b211104d RR |
2297 | { mod->unused_syms, mod->num_unused_syms }, |
2298 | { mod->unused_gpl_syms, mod->num_unused_gpl_syms }, | |
f7f5b675 | 2299 | #endif |
b211104d | 2300 | }; |
eea8b54d | 2301 | |
b211104d RR |
2302 | for (i = 0; i < ARRAY_SIZE(arr); i++) { |
2303 | for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) { | |
7290d580 | 2304 | if (find_symbol(kernel_symbol_name(s), &owner, NULL, |
5cb90343 | 2305 | true, false)) { |
bddb12b3 | 2306 | pr_err("%s: exports duplicate symbol %s" |
b211104d | 2307 | " (owned by %s)\n", |
7290d580 AB |
2308 | mod->name, kernel_symbol_name(s), |
2309 | module_name(owner)); | |
b211104d RR |
2310 | return -ENOEXEC; |
2311 | } | |
eea8b54d | 2312 | } |
b211104d RR |
2313 | } |
2314 | return 0; | |
eea8b54d AN |
2315 | } |
2316 | ||
b6f83d5d FS |
2317 | static bool ignore_undef_symbol(Elf_Half emachine, const char *name) |
2318 | { | |
2319 | /* | |
2320 | * On x86, PIC code and Clang non-PIC code may have call foo@PLT. GNU as | |
2321 | * before 2.37 produces an unreferenced _GLOBAL_OFFSET_TABLE_ on x86-64. | |
2322 | * i386 has a similar problem but may not deserve a fix. | |
2323 | * | |
2324 | * If we ever have to ignore many symbols, consider refactoring the code to | |
2325 | * only warn if referenced by a relocation. | |
2326 | */ | |
2327 | if (emachine == EM_386 || emachine == EM_X86_64) | |
2328 | return !strcmp(name, "_GLOBAL_OFFSET_TABLE_"); | |
2329 | return false; | |
2330 | } | |
2331 | ||
9a4b9708 | 2332 | /* Change all symbols so that st_value encodes the pointer directly. */ |
49668688 RR |
2333 | static int simplify_symbols(struct module *mod, const struct load_info *info) |
2334 | { | |
2335 | Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; | |
2336 | Elf_Sym *sym = (void *)symsec->sh_addr; | |
1da177e4 | 2337 | unsigned long secbase; |
49668688 | 2338 | unsigned int i; |
1da177e4 | 2339 | int ret = 0; |
414fd31b | 2340 | const struct kernel_symbol *ksym; |
1da177e4 | 2341 | |
49668688 RR |
2342 | for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) { |
2343 | const char *name = info->strtab + sym[i].st_name; | |
2344 | ||
1da177e4 LT |
2345 | switch (sym[i].st_shndx) { |
2346 | case SHN_COMMON: | |
80375980 JM |
2347 | /* Ignore common symbols */ |
2348 | if (!strncmp(name, "__gnu_lto", 9)) | |
2349 | break; | |
2350 | ||
1da177e4 LT |
2351 | /* We compiled with -fno-common. These are not |
2352 | supposed to happen. */ | |
5e124169 | 2353 | pr_debug("Common symbol: %s\n", name); |
6da0b565 | 2354 | pr_warn("%s: please compile with -fno-common\n", |
1da177e4 LT |
2355 | mod->name); |
2356 | ret = -ENOEXEC; | |
2357 | break; | |
2358 | ||
2359 | case SHN_ABS: | |
2360 | /* Don't need to do anything */ | |
5e124169 | 2361 | pr_debug("Absolute symbol: 0x%08lx\n", |
1da177e4 LT |
2362 | (long)sym[i].st_value); |
2363 | break; | |
2364 | ||
1ce15ef4 JY |
2365 | case SHN_LIVEPATCH: |
2366 | /* Livepatch symbols are resolved by livepatch */ | |
2367 | break; | |
2368 | ||
1da177e4 | 2369 | case SHN_UNDEF: |
49668688 | 2370 | ksym = resolve_symbol_wait(mod, info, name); |
1da177e4 | 2371 | /* Ok if resolved. */ |
9bea7f23 | 2372 | if (ksym && !IS_ERR(ksym)) { |
7290d580 | 2373 | sym[i].st_value = kernel_symbol_value(ksym); |
1da177e4 | 2374 | break; |
414fd31b TA |
2375 | } |
2376 | ||
b6f83d5d FS |
2377 | /* Ok if weak or ignored. */ |
2378 | if (!ksym && | |
2379 | (ELF_ST_BIND(sym[i].st_info) == STB_WEAK || | |
2380 | ignore_undef_symbol(info->hdr->e_machine, name))) | |
1da177e4 LT |
2381 | break; |
2382 | ||
9bea7f23 | 2383 | ret = PTR_ERR(ksym) ?: -ENOENT; |
62267e0e JD |
2384 | pr_warn("%s: Unknown symbol %s (err %d)\n", |
2385 | mod->name, name, ret); | |
1da177e4 LT |
2386 | break; |
2387 | ||
2388 | default: | |
2389 | /* Divert to percpu allocation if a percpu var. */ | |
49668688 | 2390 | if (sym[i].st_shndx == info->index.pcpu) |
259354de | 2391 | secbase = (unsigned long)mod_percpu(mod); |
1da177e4 | 2392 | else |
49668688 | 2393 | secbase = info->sechdrs[sym[i].st_shndx].sh_addr; |
1da177e4 LT |
2394 | sym[i].st_value += secbase; |
2395 | break; | |
2396 | } | |
2397 | } | |
2398 | ||
2399 | return ret; | |
2400 | } | |
2401 | ||
49668688 | 2402 | static int apply_relocations(struct module *mod, const struct load_info *info) |
22e268eb RR |
2403 | { |
2404 | unsigned int i; | |
2405 | int err = 0; | |
2406 | ||
2407 | /* Now do relocations. */ | |
49668688 RR |
2408 | for (i = 1; i < info->hdr->e_shnum; i++) { |
2409 | unsigned int infosec = info->sechdrs[i].sh_info; | |
22e268eb RR |
2410 | |
2411 | /* Not a valid relocation section? */ | |
49668688 | 2412 | if (infosec >= info->hdr->e_shnum) |
22e268eb RR |
2413 | continue; |
2414 | ||
2415 | /* Don't bother with non-allocated sections */ | |
49668688 | 2416 | if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC)) |
22e268eb RR |
2417 | continue; |
2418 | ||
1ce15ef4 JY |
2419 | /* Livepatch relocation sections are applied by livepatch */ |
2420 | if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH) | |
2421 | continue; | |
2422 | ||
49668688 RR |
2423 | if (info->sechdrs[i].sh_type == SHT_REL) |
2424 | err = apply_relocate(info->sechdrs, info->strtab, | |
2425 | info->index.sym, i, mod); | |
2426 | else if (info->sechdrs[i].sh_type == SHT_RELA) | |
2427 | err = apply_relocate_add(info->sechdrs, info->strtab, | |
2428 | info->index.sym, i, mod); | |
22e268eb RR |
2429 | if (err < 0) |
2430 | break; | |
2431 | } | |
2432 | return err; | |
2433 | } | |
2434 | ||
088af9a6 HD |
2435 | /* Additional bytes needed by arch in front of individual sections */ |
2436 | unsigned int __weak arch_mod_section_prepend(struct module *mod, | |
2437 | unsigned int section) | |
2438 | { | |
2439 | /* default implementation just returns zero */ | |
2440 | return 0; | |
2441 | } | |
2442 | ||
1da177e4 | 2443 | /* Update size with this section: return offset. */ |
088af9a6 HD |
2444 | static long get_offset(struct module *mod, unsigned int *size, |
2445 | Elf_Shdr *sechdr, unsigned int section) | |
1da177e4 LT |
2446 | { |
2447 | long ret; | |
2448 | ||
088af9a6 | 2449 | *size += arch_mod_section_prepend(mod, section); |
1da177e4 LT |
2450 | ret = ALIGN(*size, sechdr->sh_addralign ?: 1); |
2451 | *size = ret + sechdr->sh_size; | |
2452 | return ret; | |
2453 | } | |
2454 | ||
2455 | /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld | |
2456 | might -- code, read-only data, read-write data, small data. Tally | |
2457 | sizes, and place the offsets into sh_entsize fields: high bit means it | |
2458 | belongs in init. */ | |
49668688 | 2459 | static void layout_sections(struct module *mod, struct load_info *info) |
1da177e4 LT |
2460 | { |
2461 | static unsigned long const masks[][2] = { | |
2462 | /* NOTE: all executable code must be the first section | |
2463 | * in this array; otherwise modify the text_size | |
2464 | * finder in the two loops below */ | |
2465 | { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL }, | |
2466 | { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL }, | |
444d13ff | 2467 | { SHF_RO_AFTER_INIT | SHF_ALLOC, ARCH_SHF_SMALL }, |
1da177e4 LT |
2468 | { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL }, |
2469 | { ARCH_SHF_SMALL | SHF_ALLOC, 0 } | |
2470 | }; | |
2471 | unsigned int m, i; | |
2472 | ||
49668688 RR |
2473 | for (i = 0; i < info->hdr->e_shnum; i++) |
2474 | info->sechdrs[i].sh_entsize = ~0UL; | |
1da177e4 | 2475 | |
5e124169 | 2476 | pr_debug("Core section allocation order:\n"); |
1da177e4 | 2477 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { |
49668688 RR |
2478 | for (i = 0; i < info->hdr->e_shnum; ++i) { |
2479 | Elf_Shdr *s = &info->sechdrs[i]; | |
2480 | const char *sname = info->secstrings + s->sh_name; | |
1da177e4 LT |
2481 | |
2482 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
2483 | || (s->sh_flags & masks[m][1]) | |
2484 | || s->sh_entsize != ~0UL | |
49668688 | 2485 | || strstarts(sname, ".init")) |
1da177e4 | 2486 | continue; |
7523e4dc | 2487 | s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i); |
5e124169 | 2488 | pr_debug("\t%s\n", sname); |
1da177e4 | 2489 | } |
84e1c6bb MC |
2490 | switch (m) { |
2491 | case 0: /* executable */ | |
7523e4dc RR |
2492 | mod->core_layout.size = debug_align(mod->core_layout.size); |
2493 | mod->core_layout.text_size = mod->core_layout.size; | |
84e1c6bb MC |
2494 | break; |
2495 | case 1: /* RO: text and ro-data */ | |
7523e4dc RR |
2496 | mod->core_layout.size = debug_align(mod->core_layout.size); |
2497 | mod->core_layout.ro_size = mod->core_layout.size; | |
84e1c6bb | 2498 | break; |
444d13ff JY |
2499 | case 2: /* RO after init */ |
2500 | mod->core_layout.size = debug_align(mod->core_layout.size); | |
2501 | mod->core_layout.ro_after_init_size = mod->core_layout.size; | |
2502 | break; | |
2503 | case 4: /* whole core */ | |
7523e4dc | 2504 | mod->core_layout.size = debug_align(mod->core_layout.size); |
84e1c6bb MC |
2505 | break; |
2506 | } | |
1da177e4 LT |
2507 | } |
2508 | ||
5e124169 | 2509 | pr_debug("Init section allocation order:\n"); |
1da177e4 | 2510 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { |
49668688 RR |
2511 | for (i = 0; i < info->hdr->e_shnum; ++i) { |
2512 | Elf_Shdr *s = &info->sechdrs[i]; | |
2513 | const char *sname = info->secstrings + s->sh_name; | |
1da177e4 LT |
2514 | |
2515 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
2516 | || (s->sh_flags & masks[m][1]) | |
2517 | || s->sh_entsize != ~0UL | |
49668688 | 2518 | || !strstarts(sname, ".init")) |
1da177e4 | 2519 | continue; |
7523e4dc | 2520 | s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i) |
1da177e4 | 2521 | | INIT_OFFSET_MASK); |
5e124169 | 2522 | pr_debug("\t%s\n", sname); |
1da177e4 | 2523 | } |
84e1c6bb MC |
2524 | switch (m) { |
2525 | case 0: /* executable */ | |
7523e4dc RR |
2526 | mod->init_layout.size = debug_align(mod->init_layout.size); |
2527 | mod->init_layout.text_size = mod->init_layout.size; | |
84e1c6bb MC |
2528 | break; |
2529 | case 1: /* RO: text and ro-data */ | |
7523e4dc RR |
2530 | mod->init_layout.size = debug_align(mod->init_layout.size); |
2531 | mod->init_layout.ro_size = mod->init_layout.size; | |
84e1c6bb | 2532 | break; |
444d13ff JY |
2533 | case 2: |
2534 | /* | |
2535 | * RO after init doesn't apply to init_layout (only | |
2536 | * core_layout), so it just takes the value of ro_size. | |
2537 | */ | |
2538 | mod->init_layout.ro_after_init_size = mod->init_layout.ro_size; | |
2539 | break; | |
2540 | case 4: /* whole init */ | |
7523e4dc | 2541 | mod->init_layout.size = debug_align(mod->init_layout.size); |
84e1c6bb MC |
2542 | break; |
2543 | } | |
1da177e4 LT |
2544 | } |
2545 | } | |
2546 | ||
1da177e4 LT |
2547 | static void set_license(struct module *mod, const char *license) |
2548 | { | |
2549 | if (!license) | |
2550 | license = "unspecified"; | |
2551 | ||
fa3ba2e8 | 2552 | if (!license_is_gpl_compatible(license)) { |
25ddbb18 | 2553 | if (!test_taint(TAINT_PROPRIETARY_MODULE)) |
bddb12b3 AM |
2554 | pr_warn("%s: module license '%s' taints kernel.\n", |
2555 | mod->name, license); | |
373d4d09 RR |
2556 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
2557 | LOCKDEP_NOW_UNRELIABLE); | |
1da177e4 LT |
2558 | } |
2559 | } | |
2560 | ||
2561 | /* Parse tag=value strings from .modinfo section */ | |
2562 | static char *next_string(char *string, unsigned long *secsize) | |
2563 | { | |
2564 | /* Skip non-zero chars */ | |
2565 | while (string[0]) { | |
2566 | string++; | |
2567 | if ((*secsize)-- <= 1) | |
2568 | return NULL; | |
2569 | } | |
2570 | ||
2571 | /* Skip any zero padding. */ | |
2572 | while (!string[0]) { | |
2573 | string++; | |
2574 | if ((*secsize)-- <= 1) | |
2575 | return NULL; | |
2576 | } | |
2577 | return string; | |
2578 | } | |
2579 | ||
c5e4a062 MM |
2580 | static char *get_next_modinfo(const struct load_info *info, const char *tag, |
2581 | char *prev) | |
1da177e4 LT |
2582 | { |
2583 | char *p; | |
2584 | unsigned int taglen = strlen(tag); | |
49668688 RR |
2585 | Elf_Shdr *infosec = &info->sechdrs[info->index.info]; |
2586 | unsigned long size = infosec->sh_size; | |
1da177e4 | 2587 | |
5fdc7db6 JY |
2588 | /* |
2589 | * get_modinfo() calls made before rewrite_section_headers() | |
2590 | * must use sh_offset, as sh_addr isn't set! | |
2591 | */ | |
c5e4a062 MM |
2592 | char *modinfo = (char *)info->hdr + infosec->sh_offset; |
2593 | ||
2594 | if (prev) { | |
2595 | size -= prev - modinfo; | |
2596 | modinfo = next_string(prev, &size); | |
2597 | } | |
2598 | ||
2599 | for (p = modinfo; p; p = next_string(p, &size)) { | |
1da177e4 LT |
2600 | if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') |
2601 | return p + taglen + 1; | |
2602 | } | |
2603 | return NULL; | |
2604 | } | |
2605 | ||
c5e4a062 MM |
2606 | static char *get_modinfo(const struct load_info *info, const char *tag) |
2607 | { | |
2608 | return get_next_modinfo(info, tag, NULL); | |
2609 | } | |
2610 | ||
49668688 | 2611 | static void setup_modinfo(struct module *mod, struct load_info *info) |
c988d2b2 MD |
2612 | { |
2613 | struct module_attribute *attr; | |
2614 | int i; | |
2615 | ||
2616 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
2617 | if (attr->setup) | |
49668688 | 2618 | attr->setup(mod, get_modinfo(info, attr->attr.name)); |
c988d2b2 MD |
2619 | } |
2620 | } | |
c988d2b2 | 2621 | |
a263f776 RR |
2622 | static void free_modinfo(struct module *mod) |
2623 | { | |
2624 | struct module_attribute *attr; | |
2625 | int i; | |
2626 | ||
2627 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
2628 | if (attr->free) | |
2629 | attr->free(mod); | |
2630 | } | |
2631 | } | |
2632 | ||
1da177e4 | 2633 | #ifdef CONFIG_KALLSYMS |
15bba37d | 2634 | |
2d25bc55 JY |
2635 | /* Lookup exported symbol in given range of kernel_symbols */ |
2636 | static const struct kernel_symbol *lookup_exported_symbol(const char *name, | |
2637 | const struct kernel_symbol *start, | |
2638 | const struct kernel_symbol *stop) | |
15bba37d | 2639 | { |
9d63487f AIB |
2640 | return bsearch(name, start, stop - start, |
2641 | sizeof(struct kernel_symbol), cmp_name); | |
15bba37d WC |
2642 | } |
2643 | ||
ca4787b7 TA |
2644 | static int is_exported(const char *name, unsigned long value, |
2645 | const struct module *mod) | |
1da177e4 | 2646 | { |
ca4787b7 TA |
2647 | const struct kernel_symbol *ks; |
2648 | if (!mod) | |
2d25bc55 | 2649 | ks = lookup_exported_symbol(name, __start___ksymtab, __stop___ksymtab); |
3fd6805f | 2650 | else |
2d25bc55 JY |
2651 | ks = lookup_exported_symbol(name, mod->syms, mod->syms + mod->num_syms); |
2652 | ||
7290d580 | 2653 | return ks != NULL && kernel_symbol_value(ks) == value; |
1da177e4 LT |
2654 | } |
2655 | ||
2656 | /* As per nm */ | |
eded41c1 | 2657 | static char elf_type(const Elf_Sym *sym, const struct load_info *info) |
1da177e4 | 2658 | { |
eded41c1 RR |
2659 | const Elf_Shdr *sechdrs = info->sechdrs; |
2660 | ||
1da177e4 LT |
2661 | if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { |
2662 | if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) | |
2663 | return 'v'; | |
2664 | else | |
2665 | return 'w'; | |
2666 | } | |
2667 | if (sym->st_shndx == SHN_UNDEF) | |
2668 | return 'U'; | |
e0224418 | 2669 | if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu) |
1da177e4 LT |
2670 | return 'a'; |
2671 | if (sym->st_shndx >= SHN_LORESERVE) | |
2672 | return '?'; | |
2673 | if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) | |
2674 | return 't'; | |
2675 | if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC | |
2676 | && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { | |
2677 | if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) | |
2678 | return 'r'; | |
2679 | else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
2680 | return 'g'; | |
2681 | else | |
2682 | return 'd'; | |
2683 | } | |
2684 | if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { | |
2685 | if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
2686 | return 's'; | |
2687 | else | |
2688 | return 'b'; | |
2689 | } | |
eded41c1 RR |
2690 | if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name, |
2691 | ".debug")) { | |
1da177e4 | 2692 | return 'n'; |
eded41c1 | 2693 | } |
1da177e4 LT |
2694 | return '?'; |
2695 | } | |
2696 | ||
4a496226 | 2697 | static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs, |
e0224418 | 2698 | unsigned int shnum, unsigned int pcpundx) |
4a496226 JB |
2699 | { |
2700 | const Elf_Shdr *sec; | |
2701 | ||
2702 | if (src->st_shndx == SHN_UNDEF | |
2703 | || src->st_shndx >= shnum | |
2704 | || !src->st_name) | |
2705 | return false; | |
2706 | ||
e0224418 MB |
2707 | #ifdef CONFIG_KALLSYMS_ALL |
2708 | if (src->st_shndx == pcpundx) | |
2709 | return true; | |
2710 | #endif | |
2711 | ||
4a496226 JB |
2712 | sec = sechdrs + src->st_shndx; |
2713 | if (!(sec->sh_flags & SHF_ALLOC) | |
2714 | #ifndef CONFIG_KALLSYMS_ALL | |
2715 | || !(sec->sh_flags & SHF_EXECINSTR) | |
2716 | #endif | |
2717 | || (sec->sh_entsize & INIT_OFFSET_MASK)) | |
2718 | return false; | |
2719 | ||
2720 | return true; | |
2721 | } | |
2722 | ||
48fd1188 KC |
2723 | /* |
2724 | * We only allocate and copy the strings needed by the parts of symtab | |
2725 | * we keep. This is simple, but has the effect of making multiple | |
2726 | * copies of duplicates. We could be more sophisticated, see | |
2727 | * linux-kernel thread starting with | |
2728 | * <73defb5e4bca04a6431392cc341112b1@localhost>. | |
2729 | */ | |
49668688 | 2730 | static void layout_symtab(struct module *mod, struct load_info *info) |
4a496226 | 2731 | { |
49668688 RR |
2732 | Elf_Shdr *symsect = info->sechdrs + info->index.sym; |
2733 | Elf_Shdr *strsect = info->sechdrs + info->index.str; | |
4a496226 | 2734 | const Elf_Sym *src; |
54523ec7 | 2735 | unsigned int i, nsrc, ndst, strtab_size = 0; |
4a496226 JB |
2736 | |
2737 | /* Put symbol section at end of init part of module. */ | |
2738 | symsect->sh_flags |= SHF_ALLOC; | |
7523e4dc | 2739 | symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect, |
49668688 | 2740 | info->index.sym) | INIT_OFFSET_MASK; |
5e124169 | 2741 | pr_debug("\t%s\n", info->secstrings + symsect->sh_name); |
4a496226 | 2742 | |
49668688 | 2743 | src = (void *)info->hdr + symsect->sh_offset; |
4a496226 | 2744 | nsrc = symsect->sh_size / sizeof(*src); |
70b1e916 | 2745 | |
48fd1188 | 2746 | /* Compute total space required for the core symbols' strtab. */ |
59ef28b1 | 2747 | for (ndst = i = 0; i < nsrc; i++) { |
1ce15ef4 | 2748 | if (i == 0 || is_livepatch_module(mod) || |
e0224418 MB |
2749 | is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, |
2750 | info->index.pcpu)) { | |
59ef28b1 | 2751 | strtab_size += strlen(&info->strtab[src[i].st_name])+1; |
48fd1188 | 2752 | ndst++; |
554bdfe5 | 2753 | } |
59ef28b1 | 2754 | } |
4a496226 JB |
2755 | |
2756 | /* Append room for core symbols at end of core part. */ | |
7523e4dc RR |
2757 | info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1); |
2758 | info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym); | |
2759 | mod->core_layout.size += strtab_size; | |
1c7651f4 EL |
2760 | info->core_typeoffs = mod->core_layout.size; |
2761 | mod->core_layout.size += ndst * sizeof(char); | |
7523e4dc | 2762 | mod->core_layout.size = debug_align(mod->core_layout.size); |
4a496226 | 2763 | |
554bdfe5 JB |
2764 | /* Put string table section at end of init part of module. */ |
2765 | strsect->sh_flags |= SHF_ALLOC; | |
7523e4dc | 2766 | strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect, |
49668688 | 2767 | info->index.str) | INIT_OFFSET_MASK; |
5e124169 | 2768 | pr_debug("\t%s\n", info->secstrings + strsect->sh_name); |
8244062e RR |
2769 | |
2770 | /* We'll tack temporary mod_kallsyms on the end. */ | |
2771 | mod->init_layout.size = ALIGN(mod->init_layout.size, | |
2772 | __alignof__(struct mod_kallsyms)); | |
2773 | info->mod_kallsyms_init_off = mod->init_layout.size; | |
2774 | mod->init_layout.size += sizeof(struct mod_kallsyms); | |
1c7651f4 EL |
2775 | info->init_typeoffs = mod->init_layout.size; |
2776 | mod->init_layout.size += nsrc * sizeof(char); | |
8244062e | 2777 | mod->init_layout.size = debug_align(mod->init_layout.size); |
4a496226 JB |
2778 | } |
2779 | ||
8244062e RR |
2780 | /* |
2781 | * We use the full symtab and strtab which layout_symtab arranged to | |
2782 | * be appended to the init section. Later we switch to the cut-down | |
2783 | * core-only ones. | |
2784 | */ | |
811d66a0 | 2785 | static void add_kallsyms(struct module *mod, const struct load_info *info) |
1da177e4 | 2786 | { |
4a496226 JB |
2787 | unsigned int i, ndst; |
2788 | const Elf_Sym *src; | |
2789 | Elf_Sym *dst; | |
554bdfe5 | 2790 | char *s; |
eded41c1 | 2791 | Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; |
1da177e4 | 2792 | |
8244062e RR |
2793 | /* Set up to point into init section. */ |
2794 | mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off; | |
2795 | ||
2796 | mod->kallsyms->symtab = (void *)symsec->sh_addr; | |
2797 | mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym); | |
511ca6ae | 2798 | /* Make sure we get permanent strtab: don't use info->strtab. */ |
8244062e | 2799 | mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr; |
1c7651f4 | 2800 | mod->kallsyms->typetab = mod->init_layout.base + info->init_typeoffs; |
1da177e4 | 2801 | |
1c7651f4 EL |
2802 | /* |
2803 | * Now populate the cut down core kallsyms for after init | |
2804 | * and set types up while we still have access to sections. | |
2805 | */ | |
8244062e RR |
2806 | mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs; |
2807 | mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs; | |
1c7651f4 | 2808 | mod->core_kallsyms.typetab = mod->core_layout.base + info->core_typeoffs; |
8244062e RR |
2809 | src = mod->kallsyms->symtab; |
2810 | for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) { | |
1c7651f4 | 2811 | mod->kallsyms->typetab[i] = elf_type(src + i, info); |
1ce15ef4 | 2812 | if (i == 0 || is_livepatch_module(mod) || |
e0224418 MB |
2813 | is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, |
2814 | info->index.pcpu)) { | |
1c7651f4 EL |
2815 | mod->core_kallsyms.typetab[ndst] = |
2816 | mod->kallsyms->typetab[i]; | |
59ef28b1 | 2817 | dst[ndst] = src[i]; |
8244062e RR |
2818 | dst[ndst++].st_name = s - mod->core_kallsyms.strtab; |
2819 | s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name], | |
59ef28b1 RR |
2820 | KSYM_NAME_LEN) + 1; |
2821 | } | |
4a496226 | 2822 | } |
8244062e | 2823 | mod->core_kallsyms.num_symtab = ndst; |
1da177e4 LT |
2824 | } |
2825 | #else | |
49668688 | 2826 | static inline void layout_symtab(struct module *mod, struct load_info *info) |
4a496226 JB |
2827 | { |
2828 | } | |
3ae91c21 | 2829 | |
abbce906 | 2830 | static void add_kallsyms(struct module *mod, const struct load_info *info) |
1da177e4 LT |
2831 | { |
2832 | } | |
2833 | #endif /* CONFIG_KALLSYMS */ | |
2834 | ||
52796312 | 2835 | static void dynamic_debug_setup(struct module *mod, struct _ddebug *debug, unsigned int num) |
346e15be | 2836 | { |
811d66a0 RR |
2837 | if (!debug) |
2838 | return; | |
513770f5 | 2839 | ddebug_add_module(debug, num, mod->name); |
5e458cc0 | 2840 | } |
346e15be | 2841 | |
52796312 | 2842 | static void dynamic_debug_remove(struct module *mod, struct _ddebug *debug) |
ff49d74a YS |
2843 | { |
2844 | if (debug) | |
52796312 | 2845 | ddebug_remove_module(mod->name); |
ff49d74a YS |
2846 | } |
2847 | ||
74e08fcf JB |
2848 | void * __weak module_alloc(unsigned long size) |
2849 | { | |
82fab442 | 2850 | return vmalloc_exec(size); |
74e08fcf JB |
2851 | } |
2852 | ||
38b37d63 MS |
2853 | bool __weak module_exit_section(const char *name) |
2854 | { | |
2855 | return strstarts(name, ".exit"); | |
2856 | } | |
2857 | ||
4f2294b6 | 2858 | #ifdef CONFIG_DEBUG_KMEMLEAK |
49668688 RR |
2859 | static void kmemleak_load_module(const struct module *mod, |
2860 | const struct load_info *info) | |
4f2294b6 CM |
2861 | { |
2862 | unsigned int i; | |
2863 | ||
2864 | /* only scan the sections containing data */ | |
c017b4be | 2865 | kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL); |
4f2294b6 | 2866 | |
49668688 | 2867 | for (i = 1; i < info->hdr->e_shnum; i++) { |
06c9494c SR |
2868 | /* Scan all writable sections that's not executable */ |
2869 | if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) || | |
2870 | !(info->sechdrs[i].sh_flags & SHF_WRITE) || | |
2871 | (info->sechdrs[i].sh_flags & SHF_EXECINSTR)) | |
4f2294b6 CM |
2872 | continue; |
2873 | ||
49668688 RR |
2874 | kmemleak_scan_area((void *)info->sechdrs[i].sh_addr, |
2875 | info->sechdrs[i].sh_size, GFP_KERNEL); | |
4f2294b6 CM |
2876 | } |
2877 | } | |
2878 | #else | |
49668688 RR |
2879 | static inline void kmemleak_load_module(const struct module *mod, |
2880 | const struct load_info *info) | |
4f2294b6 CM |
2881 | { |
2882 | } | |
2883 | #endif | |
2884 | ||
106a4ee2 | 2885 | #ifdef CONFIG_MODULE_SIG |
bca014ca | 2886 | static int module_sig_check(struct load_info *info, int flags) |
106a4ee2 | 2887 | { |
49fcf732 | 2888 | int err = -ENODATA; |
34e1169d | 2889 | const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; |
49fcf732 | 2890 | const char *reason; |
34e1169d | 2891 | const void *mod = info->hdr; |
caabe240 | 2892 | |
bca014ca BH |
2893 | /* |
2894 | * Require flags == 0, as a module with version information | |
2895 | * removed is no longer the module that was signed | |
2896 | */ | |
2897 | if (flags == 0 && | |
2898 | info->len > markerlen && | |
34e1169d | 2899 | memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) { |
caabe240 | 2900 | /* We truncate the module to discard the signature */ |
34e1169d | 2901 | info->len -= markerlen; |
f314dfea | 2902 | err = mod_verify_sig(mod, info); |
106a4ee2 RR |
2903 | } |
2904 | ||
49fcf732 DH |
2905 | switch (err) { |
2906 | case 0: | |
106a4ee2 RR |
2907 | info->sig_ok = true; |
2908 | return 0; | |
106a4ee2 | 2909 | |
49fcf732 DH |
2910 | /* We don't permit modules to be loaded into trusted kernels |
2911 | * without a valid signature on them, but if we're not | |
2912 | * enforcing, certain errors are non-fatal. | |
2913 | */ | |
2914 | case -ENODATA: | |
40c04cd7 | 2915 | reason = "unsigned module"; |
ec840f9b | 2916 | break; |
49fcf732 | 2917 | case -ENOPKG: |
40c04cd7 | 2918 | reason = "module with unsupported crypto"; |
ec840f9b | 2919 | break; |
49fcf732 | 2920 | case -ENOKEY: |
40c04cd7 | 2921 | reason = "module with unavailable key"; |
ec840f9b | 2922 | break; |
49fcf732 DH |
2923 | |
2924 | /* All other errors are fatal, including nomem, unparseable | |
2925 | * signatures and signature check failures - even if signatures | |
2926 | * aren't required. | |
2927 | */ | |
2928 | default: | |
2929 | return err; | |
2930 | } | |
ec840f9b SS |
2931 | |
2932 | if (is_module_sig_enforced()) { | |
c40724b7 | 2933 | pr_notice("Loading of %s is rejected\n", reason); |
ec840f9b SS |
2934 | return -EKEYREJECTED; |
2935 | } | |
2936 | ||
2937 | return security_locked_down(LOCKDOWN_MODULE_SIGNATURE); | |
106a4ee2 RR |
2938 | } |
2939 | #else /* !CONFIG_MODULE_SIG */ | |
bca014ca | 2940 | static int module_sig_check(struct load_info *info, int flags) |
106a4ee2 RR |
2941 | { |
2942 | return 0; | |
2943 | } | |
2944 | #endif /* !CONFIG_MODULE_SIG */ | |
2945 | ||
c40724b7 | 2946 | static int validate_section_offset(struct load_info *info, Elf_Shdr *shdr) |
40dd2560 | 2947 | { |
c40724b7 FL |
2948 | unsigned long secend; |
2949 | ||
2950 | /* | |
2951 | * Check for both overflow and offset/size being | |
2952 | * too large. | |
2953 | */ | |
2954 | secend = shdr->sh_offset + shdr->sh_size; | |
2955 | if (secend < shdr->sh_offset || secend > info->len) | |
2956 | return -ENOEXEC; | |
2957 | ||
2958 | return 0; | |
2959 | } | |
2960 | ||
2961 | /* | |
2962 | * Sanity checks against invalid binaries, wrong arch, weird elf version. | |
2963 | * | |
2964 | * Also do basic validity checks against section offsets and sizes, the | |
2965 | * section name string table, and the indices used for it (sh_name). | |
2966 | */ | |
2967 | static int elf_validity_check(struct load_info *info) | |
2968 | { | |
2969 | unsigned int i; | |
2970 | Elf_Shdr *shdr, *strhdr; | |
2971 | int err; | |
2972 | ||
34e1169d KC |
2973 | if (info->len < sizeof(*(info->hdr))) |
2974 | return -ENOEXEC; | |
2975 | ||
2976 | if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0 | |
2977 | || info->hdr->e_type != ET_REL | |
2978 | || !elf_check_arch(info->hdr) | |
2979 | || info->hdr->e_shentsize != sizeof(Elf_Shdr)) | |
2980 | return -ENOEXEC; | |
2981 | ||
c40724b7 FL |
2982 | /* |
2983 | * e_shnum is 16 bits, and sizeof(Elf_Shdr) is | |
2984 | * known and small. So e_shnum * sizeof(Elf_Shdr) | |
2985 | * will not overflow unsigned long on any platform. | |
2986 | */ | |
34e1169d KC |
2987 | if (info->hdr->e_shoff >= info->len |
2988 | || (info->hdr->e_shnum * sizeof(Elf_Shdr) > | |
2989 | info->len - info->hdr->e_shoff)) | |
2990 | return -ENOEXEC; | |
40dd2560 | 2991 | |
c40724b7 FL |
2992 | info->sechdrs = (void *)info->hdr + info->hdr->e_shoff; |
2993 | ||
2994 | /* | |
2995 | * Verify if the section name table index is valid. | |
2996 | */ | |
2997 | if (info->hdr->e_shstrndx == SHN_UNDEF | |
2998 | || info->hdr->e_shstrndx >= info->hdr->e_shnum) | |
2999 | return -ENOEXEC; | |
3000 | ||
3001 | strhdr = &info->sechdrs[info->hdr->e_shstrndx]; | |
3002 | err = validate_section_offset(info, strhdr); | |
3003 | if (err < 0) | |
3004 | return err; | |
3005 | ||
3006 | /* | |
3007 | * The section name table must be NUL-terminated, as required | |
3008 | * by the spec. This makes strcmp and pr_* calls that access | |
3009 | * strings in the section safe. | |
3010 | */ | |
3011 | info->secstrings = (void *)info->hdr + strhdr->sh_offset; | |
3012 | if (info->secstrings[strhdr->sh_size - 1] != '\0') | |
3013 | return -ENOEXEC; | |
3014 | ||
3015 | /* | |
3016 | * The code assumes that section 0 has a length of zero and | |
3017 | * an addr of zero, so check for it. | |
3018 | */ | |
3019 | if (info->sechdrs[0].sh_type != SHT_NULL | |
3020 | || info->sechdrs[0].sh_size != 0 | |
3021 | || info->sechdrs[0].sh_addr != 0) | |
3022 | return -ENOEXEC; | |
3023 | ||
3024 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
3025 | shdr = &info->sechdrs[i]; | |
3026 | switch (shdr->sh_type) { | |
3027 | case SHT_NULL: | |
3028 | case SHT_NOBITS: | |
3029 | continue; | |
3030 | case SHT_SYMTAB: | |
3031 | if (shdr->sh_link == SHN_UNDEF | |
3032 | || shdr->sh_link >= info->hdr->e_shnum) | |
3033 | return -ENOEXEC; | |
3034 | fallthrough; | |
3035 | default: | |
3036 | err = validate_section_offset(info, shdr); | |
3037 | if (err < 0) { | |
3038 | pr_err("Invalid ELF section in module (section %u type %u)\n", | |
3039 | i, shdr->sh_type); | |
3040 | return err; | |
3041 | } | |
3042 | ||
3043 | if (shdr->sh_flags & SHF_ALLOC) { | |
3044 | if (shdr->sh_name >= strhdr->sh_size) { | |
3045 | pr_err("Invalid ELF section name in module (section %u type %u)\n", | |
3046 | i, shdr->sh_type); | |
3047 | return -ENOEXEC; | |
3048 | } | |
3049 | } | |
3050 | break; | |
3051 | } | |
3052 | } | |
3053 | ||
34e1169d KC |
3054 | return 0; |
3055 | } | |
3056 | ||
3afe9f84 LT |
3057 | #define COPY_CHUNK_SIZE (16*PAGE_SIZE) |
3058 | ||
3059 | static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len) | |
3060 | { | |
3061 | do { | |
3062 | unsigned long n = min(len, COPY_CHUNK_SIZE); | |
3063 | ||
3064 | if (copy_from_user(dst, usrc, n) != 0) | |
3065 | return -EFAULT; | |
3066 | cond_resched(); | |
3067 | dst += n; | |
3068 | usrc += n; | |
3069 | len -= n; | |
3070 | } while (len); | |
3071 | return 0; | |
3072 | } | |
3073 | ||
1ce15ef4 | 3074 | #ifdef CONFIG_LIVEPATCH |
2992ef29 | 3075 | static int check_modinfo_livepatch(struct module *mod, struct load_info *info) |
1ce15ef4 | 3076 | { |
2992ef29 JP |
3077 | if (get_modinfo(info, "livepatch")) { |
3078 | mod->klp = true; | |
3079 | add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK); | |
7598d167 JL |
3080 | pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n", |
3081 | mod->name); | |
2992ef29 | 3082 | } |
1ce15ef4 JY |
3083 | |
3084 | return 0; | |
3085 | } | |
3086 | #else /* !CONFIG_LIVEPATCH */ | |
2992ef29 | 3087 | static int check_modinfo_livepatch(struct module *mod, struct load_info *info) |
1ce15ef4 JY |
3088 | { |
3089 | if (get_modinfo(info, "livepatch")) { | |
3090 | pr_err("%s: module is marked as livepatch module, but livepatch support is disabled", | |
3091 | mod->name); | |
3092 | return -ENOEXEC; | |
3093 | } | |
3094 | ||
3095 | return 0; | |
3096 | } | |
3097 | #endif /* CONFIG_LIVEPATCH */ | |
3098 | ||
caf7501a AK |
3099 | static void check_modinfo_retpoline(struct module *mod, struct load_info *info) |
3100 | { | |
3101 | if (retpoline_module_ok(get_modinfo(info, "retpoline"))) | |
3102 | return; | |
3103 | ||
3104 | pr_warn("%s: loading module not compiled with retpoline compiler.\n", | |
3105 | mod->name); | |
3106 | } | |
3107 | ||
34e1169d KC |
3108 | /* Sets info->hdr and info->len. */ |
3109 | static int copy_module_from_user(const void __user *umod, unsigned long len, | |
3110 | struct load_info *info) | |
40dd2560 RR |
3111 | { |
3112 | int err; | |
40dd2560 | 3113 | |
34e1169d KC |
3114 | info->len = len; |
3115 | if (info->len < sizeof(*(info->hdr))) | |
40dd2560 RR |
3116 | return -ENOEXEC; |
3117 | ||
c77b8cdf | 3118 | err = security_kernel_load_data(LOADING_MODULE); |
2e72d51b KC |
3119 | if (err) |
3120 | return err; | |
3121 | ||
40dd2560 | 3122 | /* Suck in entire file: we'll want most of it. */ |
cc9e605d | 3123 | info->hdr = __vmalloc(info->len, |
19809c2d | 3124 | GFP_KERNEL | __GFP_NOWARN, PAGE_KERNEL); |
34e1169d | 3125 | if (!info->hdr) |
40dd2560 RR |
3126 | return -ENOMEM; |
3127 | ||
3afe9f84 | 3128 | if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) { |
34e1169d KC |
3129 | vfree(info->hdr); |
3130 | return -EFAULT; | |
40dd2560 RR |
3131 | } |
3132 | ||
34e1169d KC |
3133 | return 0; |
3134 | } | |
3135 | ||
d913188c RR |
3136 | static void free_copy(struct load_info *info) |
3137 | { | |
d913188c RR |
3138 | vfree(info->hdr); |
3139 | } | |
3140 | ||
2f3238ae | 3141 | static int rewrite_section_headers(struct load_info *info, int flags) |
8b5f61a7 RR |
3142 | { |
3143 | unsigned int i; | |
3144 | ||
3145 | /* This should always be true, but let's be sure. */ | |
3146 | info->sechdrs[0].sh_addr = 0; | |
3147 | ||
3148 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
3149 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
8b5f61a7 RR |
3150 | |
3151 | /* Mark all sections sh_addr with their address in the | |
3152 | temporary image. */ | |
3153 | shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset; | |
3154 | ||
3155 | #ifndef CONFIG_MODULE_UNLOAD | |
3156 | /* Don't load .exit sections */ | |
38b37d63 | 3157 | if (module_exit_section(info->secstrings+shdr->sh_name)) |
8b5f61a7 RR |
3158 | shdr->sh_flags &= ~(unsigned long)SHF_ALLOC; |
3159 | #endif | |
8b5f61a7 | 3160 | } |
d6df72a0 RR |
3161 | |
3162 | /* Track but don't keep modinfo and version sections. */ | |
3e2e857f | 3163 | info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC; |
d6df72a0 | 3164 | info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC; |
3e2e857f | 3165 | |
8b5f61a7 RR |
3166 | return 0; |
3167 | } | |
3168 | ||
3264d3f9 LT |
3169 | /* |
3170 | * Set up our basic convenience variables (pointers to section headers, | |
3171 | * search for module section index etc), and do some basic section | |
3172 | * verification. | |
3173 | * | |
81a0abd9 JY |
3174 | * Set info->mod to the temporary copy of the module in info->hdr. The final one |
3175 | * will be allocated in move_module(). | |
3264d3f9 | 3176 | */ |
81a0abd9 | 3177 | static int setup_load_info(struct load_info *info, int flags) |
3264d3f9 LT |
3178 | { |
3179 | unsigned int i; | |
3264d3f9 | 3180 | |
5fdc7db6 JY |
3181 | /* Try to find a name early so we can log errors with a module name */ |
3182 | info->index.info = find_sec(info, ".modinfo"); | |
fde4a71f | 3183 | if (info->index.info) |
5fdc7db6 | 3184 | info->name = get_modinfo(info, "name"); |
3264d3f9 | 3185 | |
8b5f61a7 RR |
3186 | /* Find internal symbols and strings. */ |
3187 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
3264d3f9 LT |
3188 | if (info->sechdrs[i].sh_type == SHT_SYMTAB) { |
3189 | info->index.sym = i; | |
3190 | info->index.str = info->sechdrs[i].sh_link; | |
8b5f61a7 RR |
3191 | info->strtab = (char *)info->hdr |
3192 | + info->sechdrs[info->index.str].sh_offset; | |
3193 | break; | |
3264d3f9 | 3194 | } |
3264d3f9 LT |
3195 | } |
3196 | ||
5fdc7db6 | 3197 | if (info->index.sym == 0) { |
fde4a71f JY |
3198 | pr_warn("%s: module has no symbols (stripped?)\n", |
3199 | info->name ?: "(missing .modinfo section or name field)"); | |
5fdc7db6 JY |
3200 | return -ENOEXEC; |
3201 | } | |
3202 | ||
49668688 | 3203 | info->index.mod = find_sec(info, ".gnu.linkonce.this_module"); |
3264d3f9 | 3204 | if (!info->index.mod) { |
3e2e857f | 3205 | pr_warn("%s: No module found in object\n", |
fde4a71f | 3206 | info->name ?: "(missing .modinfo section or name field)"); |
81a0abd9 | 3207 | return -ENOEXEC; |
3264d3f9 LT |
3208 | } |
3209 | /* This is temporary: point mod into copy of data. */ | |
5fdc7db6 | 3210 | info->mod = (void *)info->hdr + info->sechdrs[info->index.mod].sh_offset; |
3264d3f9 | 3211 | |
3e2e857f | 3212 | /* |
5fdc7db6 | 3213 | * If we didn't load the .modinfo 'name' field earlier, fall back to |
3e2e857f KC |
3214 | * on-disk struct mod 'name' field. |
3215 | */ | |
3216 | if (!info->name) | |
81a0abd9 | 3217 | info->name = info->mod->name; |
3e2e857f | 3218 | |
5fdc7db6 JY |
3219 | if (flags & MODULE_INIT_IGNORE_MODVERSIONS) |
3220 | info->index.vers = 0; /* Pretend no __versions section! */ | |
3221 | else | |
3222 | info->index.vers = find_sec(info, "__versions"); | |
3264d3f9 | 3223 | |
49668688 | 3224 | info->index.pcpu = find_pcpusec(info); |
3264d3f9 | 3225 | |
81a0abd9 | 3226 | return 0; |
3264d3f9 LT |
3227 | } |
3228 | ||
2f3238ae | 3229 | static int check_modinfo(struct module *mod, struct load_info *info, int flags) |
40dd2560 | 3230 | { |
49668688 | 3231 | const char *modmagic = get_modinfo(info, "vermagic"); |
40dd2560 RR |
3232 | int err; |
3233 | ||
2f3238ae RR |
3234 | if (flags & MODULE_INIT_IGNORE_VERMAGIC) |
3235 | modmagic = NULL; | |
3236 | ||
40dd2560 RR |
3237 | /* This is allowed: modprobe --force will invalidate it. */ |
3238 | if (!modmagic) { | |
3239 | err = try_to_force_load(mod, "bad vermagic"); | |
3240 | if (err) | |
3241 | return err; | |
49668688 | 3242 | } else if (!same_magic(modmagic, vermagic, info->index.vers)) { |
bddb12b3 | 3243 | pr_err("%s: version magic '%s' should be '%s'\n", |
3e2e857f | 3244 | info->name, modmagic, vermagic); |
40dd2560 RR |
3245 | return -ENOEXEC; |
3246 | } | |
3247 | ||
3205c36c LP |
3248 | if (!get_modinfo(info, "intree")) { |
3249 | if (!test_taint(TAINT_OOT_MODULE)) | |
3250 | pr_warn("%s: loading out-of-tree module taints kernel.\n", | |
3251 | mod->name); | |
373d4d09 | 3252 | add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK); |
3205c36c | 3253 | } |
2449b8ba | 3254 | |
caf7501a AK |
3255 | check_modinfo_retpoline(mod, info); |
3256 | ||
49668688 | 3257 | if (get_modinfo(info, "staging")) { |
373d4d09 | 3258 | add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK); |
bddb12b3 AM |
3259 | pr_warn("%s: module is from the staging directory, the quality " |
3260 | "is unknown, you have been warned.\n", mod->name); | |
40dd2560 | 3261 | } |
22e268eb | 3262 | |
2992ef29 | 3263 | err = check_modinfo_livepatch(mod, info); |
1ce15ef4 JY |
3264 | if (err) |
3265 | return err; | |
3266 | ||
22e268eb | 3267 | /* Set up license info based on the info section */ |
49668688 | 3268 | set_license(mod, get_modinfo(info, "license")); |
22e268eb | 3269 | |
40dd2560 RR |
3270 | return 0; |
3271 | } | |
3272 | ||
eb3057df | 3273 | static int find_module_sections(struct module *mod, struct load_info *info) |
f91a13bb | 3274 | { |
49668688 | 3275 | mod->kp = section_objs(info, "__param", |
f91a13bb | 3276 | sizeof(*mod->kp), &mod->num_kp); |
49668688 | 3277 | mod->syms = section_objs(info, "__ksymtab", |
f91a13bb | 3278 | sizeof(*mod->syms), &mod->num_syms); |
49668688 RR |
3279 | mod->crcs = section_addr(info, "__kcrctab"); |
3280 | mod->gpl_syms = section_objs(info, "__ksymtab_gpl", | |
f91a13bb LT |
3281 | sizeof(*mod->gpl_syms), |
3282 | &mod->num_gpl_syms); | |
49668688 RR |
3283 | mod->gpl_crcs = section_addr(info, "__kcrctab_gpl"); |
3284 | mod->gpl_future_syms = section_objs(info, | |
f91a13bb LT |
3285 | "__ksymtab_gpl_future", |
3286 | sizeof(*mod->gpl_future_syms), | |
3287 | &mod->num_gpl_future_syms); | |
49668688 | 3288 | mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future"); |
f91a13bb LT |
3289 | |
3290 | #ifdef CONFIG_UNUSED_SYMBOLS | |
49668688 | 3291 | mod->unused_syms = section_objs(info, "__ksymtab_unused", |
f91a13bb LT |
3292 | sizeof(*mod->unused_syms), |
3293 | &mod->num_unused_syms); | |
49668688 RR |
3294 | mod->unused_crcs = section_addr(info, "__kcrctab_unused"); |
3295 | mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl", | |
f91a13bb LT |
3296 | sizeof(*mod->unused_gpl_syms), |
3297 | &mod->num_unused_gpl_syms); | |
49668688 | 3298 | mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl"); |
f91a13bb LT |
3299 | #endif |
3300 | #ifdef CONFIG_CONSTRUCTORS | |
49668688 | 3301 | mod->ctors = section_objs(info, ".ctors", |
f91a13bb | 3302 | sizeof(*mod->ctors), &mod->num_ctors); |
eb3057df FH |
3303 | if (!mod->ctors) |
3304 | mod->ctors = section_objs(info, ".init_array", | |
3305 | sizeof(*mod->ctors), &mod->num_ctors); | |
3306 | else if (find_sec(info, ".init_array")) { | |
3307 | /* | |
3308 | * This shouldn't happen with same compiler and binutils | |
3309 | * building all parts of the module. | |
3310 | */ | |
6da0b565 | 3311 | pr_warn("%s: has both .ctors and .init_array.\n", |
eb3057df FH |
3312 | mod->name); |
3313 | return -EINVAL; | |
3314 | } | |
f91a13bb LT |
3315 | #endif |
3316 | ||
3317 | #ifdef CONFIG_TRACEPOINTS | |
65498646 MD |
3318 | mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs", |
3319 | sizeof(*mod->tracepoints_ptrs), | |
3320 | &mod->num_tracepoints); | |
f91a13bb | 3321 | #endif |
fe15b50c PM |
3322 | #ifdef CONFIG_TREE_SRCU |
3323 | mod->srcu_struct_ptrs = section_objs(info, "___srcu_struct_ptrs", | |
3324 | sizeof(*mod->srcu_struct_ptrs), | |
3325 | &mod->num_srcu_structs); | |
3326 | #endif | |
a38d1107 MM |
3327 | #ifdef CONFIG_BPF_EVENTS |
3328 | mod->bpf_raw_events = section_objs(info, "__bpf_raw_tp_map", | |
3329 | sizeof(*mod->bpf_raw_events), | |
3330 | &mod->num_bpf_raw_events); | |
3331 | #endif | |
e9666d10 | 3332 | #ifdef CONFIG_JUMP_LABEL |
bf5438fc JB |
3333 | mod->jump_entries = section_objs(info, "__jump_table", |
3334 | sizeof(*mod->jump_entries), | |
3335 | &mod->num_jump_entries); | |
3336 | #endif | |
f91a13bb | 3337 | #ifdef CONFIG_EVENT_TRACING |
49668688 | 3338 | mod->trace_events = section_objs(info, "_ftrace_events", |
f91a13bb LT |
3339 | sizeof(*mod->trace_events), |
3340 | &mod->num_trace_events); | |
99be647c JL |
3341 | mod->trace_evals = section_objs(info, "_ftrace_eval_map", |
3342 | sizeof(*mod->trace_evals), | |
3343 | &mod->num_trace_evals); | |
f91a13bb | 3344 | #endif |
13b9b6e7 SR |
3345 | #ifdef CONFIG_TRACING |
3346 | mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt", | |
3347 | sizeof(*mod->trace_bprintk_fmt_start), | |
3348 | &mod->num_trace_bprintk_fmt); | |
13b9b6e7 | 3349 | #endif |
f91a13bb LT |
3350 | #ifdef CONFIG_FTRACE_MCOUNT_RECORD |
3351 | /* sechdrs[0].sh_size is always zero */ | |
da5263f7 | 3352 | mod->ftrace_callsites = section_objs(info, FTRACE_CALLSITE_SECTION, |
f91a13bb LT |
3353 | sizeof(*mod->ftrace_callsites), |
3354 | &mod->num_ftrace_callsites); | |
3355 | #endif | |
540adea3 MH |
3356 | #ifdef CONFIG_FUNCTION_ERROR_INJECTION |
3357 | mod->ei_funcs = section_objs(info, "_error_injection_whitelist", | |
3358 | sizeof(*mod->ei_funcs), | |
3359 | &mod->num_ei_funcs); | |
92ace999 | 3360 | #endif |
811d66a0 RR |
3361 | mod->extable = section_objs(info, "__ex_table", |
3362 | sizeof(*mod->extable), &mod->num_exentries); | |
3363 | ||
49668688 | 3364 | if (section_addr(info, "__obsparm")) |
bddb12b3 | 3365 | pr_warn("%s: Ignoring obsolete parameters\n", mod->name); |
811d66a0 RR |
3366 | |
3367 | info->debug = section_objs(info, "__verbose", | |
3368 | sizeof(*info->debug), &info->num_debug); | |
eb3057df FH |
3369 | |
3370 | return 0; | |
f91a13bb LT |
3371 | } |
3372 | ||
49668688 | 3373 | static int move_module(struct module *mod, struct load_info *info) |
65b8a9b4 LT |
3374 | { |
3375 | int i; | |
3376 | void *ptr; | |
3377 | ||
3378 | /* Do the allocs. */ | |
7523e4dc | 3379 | ptr = module_alloc(mod->core_layout.size); |
65b8a9b4 LT |
3380 | /* |
3381 | * The pointer to this block is stored in the module structure | |
3382 | * which is inside the block. Just mark it as not being a | |
3383 | * leak. | |
3384 | */ | |
3385 | kmemleak_not_leak(ptr); | |
3386 | if (!ptr) | |
d913188c | 3387 | return -ENOMEM; |
65b8a9b4 | 3388 | |
7523e4dc RR |
3389 | memset(ptr, 0, mod->core_layout.size); |
3390 | mod->core_layout.base = ptr; | |
65b8a9b4 | 3391 | |
7523e4dc RR |
3392 | if (mod->init_layout.size) { |
3393 | ptr = module_alloc(mod->init_layout.size); | |
82fab442 RR |
3394 | /* |
3395 | * The pointer to this block is stored in the module structure | |
3396 | * which is inside the block. This block doesn't need to be | |
3397 | * scanned as it contains data and code that will be freed | |
3398 | * after the module is initialized. | |
3399 | */ | |
3400 | kmemleak_ignore(ptr); | |
3401 | if (!ptr) { | |
7523e4dc | 3402 | module_memfree(mod->core_layout.base); |
82fab442 RR |
3403 | return -ENOMEM; |
3404 | } | |
7523e4dc RR |
3405 | memset(ptr, 0, mod->init_layout.size); |
3406 | mod->init_layout.base = ptr; | |
82fab442 | 3407 | } else |
7523e4dc | 3408 | mod->init_layout.base = NULL; |
65b8a9b4 LT |
3409 | |
3410 | /* Transfer each section which specifies SHF_ALLOC */ | |
5e124169 | 3411 | pr_debug("final section addresses:\n"); |
49668688 | 3412 | for (i = 0; i < info->hdr->e_shnum; i++) { |
65b8a9b4 | 3413 | void *dest; |
49668688 | 3414 | Elf_Shdr *shdr = &info->sechdrs[i]; |
65b8a9b4 | 3415 | |
49668688 | 3416 | if (!(shdr->sh_flags & SHF_ALLOC)) |
65b8a9b4 LT |
3417 | continue; |
3418 | ||
49668688 | 3419 | if (shdr->sh_entsize & INIT_OFFSET_MASK) |
7523e4dc | 3420 | dest = mod->init_layout.base |
49668688 | 3421 | + (shdr->sh_entsize & ~INIT_OFFSET_MASK); |
65b8a9b4 | 3422 | else |
7523e4dc | 3423 | dest = mod->core_layout.base + shdr->sh_entsize; |
65b8a9b4 | 3424 | |
49668688 RR |
3425 | if (shdr->sh_type != SHT_NOBITS) |
3426 | memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size); | |
65b8a9b4 | 3427 | /* Update sh_addr to point to copy in image. */ |
49668688 | 3428 | shdr->sh_addr = (unsigned long)dest; |
5e124169 JC |
3429 | pr_debug("\t0x%lx %s\n", |
3430 | (long)shdr->sh_addr, info->secstrings + shdr->sh_name); | |
65b8a9b4 | 3431 | } |
d913188c RR |
3432 | |
3433 | return 0; | |
65b8a9b4 LT |
3434 | } |
3435 | ||
49668688 | 3436 | static int check_module_license_and_versions(struct module *mod) |
22e268eb | 3437 | { |
3205c36c LP |
3438 | int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE); |
3439 | ||
22e268eb RR |
3440 | /* |
3441 | * ndiswrapper is under GPL by itself, but loads proprietary modules. | |
3442 | * Don't use add_taint_module(), as it would prevent ndiswrapper from | |
3443 | * using GPL-only symbols it needs. | |
3444 | */ | |
3445 | if (strcmp(mod->name, "ndiswrapper") == 0) | |
373d4d09 | 3446 | add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE); |
22e268eb RR |
3447 | |
3448 | /* driverloader was caught wrongly pretending to be under GPL */ | |
3449 | if (strcmp(mod->name, "driverloader") == 0) | |
373d4d09 RR |
3450 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
3451 | LOCKDEP_NOW_UNRELIABLE); | |
22e268eb | 3452 | |
c99af375 MG |
3453 | /* lve claims to be GPL but upstream won't provide source */ |
3454 | if (strcmp(mod->name, "lve") == 0) | |
373d4d09 RR |
3455 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
3456 | LOCKDEP_NOW_UNRELIABLE); | |
c99af375 | 3457 | |
3205c36c LP |
3458 | if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE)) |
3459 | pr_warn("%s: module license taints kernel.\n", mod->name); | |
3460 | ||
22e268eb RR |
3461 | #ifdef CONFIG_MODVERSIONS |
3462 | if ((mod->num_syms && !mod->crcs) | |
3463 | || (mod->num_gpl_syms && !mod->gpl_crcs) | |
3464 | || (mod->num_gpl_future_syms && !mod->gpl_future_crcs) | |
3465 | #ifdef CONFIG_UNUSED_SYMBOLS | |
3466 | || (mod->num_unused_syms && !mod->unused_crcs) | |
3467 | || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs) | |
3468 | #endif | |
3469 | ) { | |
3470 | return try_to_force_load(mod, | |
3471 | "no versions for exported symbols"); | |
3472 | } | |
3473 | #endif | |
3474 | return 0; | |
3475 | } | |
3476 | ||
3477 | static void flush_module_icache(const struct module *mod) | |
3478 | { | |
3479 | mm_segment_t old_fs; | |
3480 | ||
3481 | /* flush the icache in correct context */ | |
3482 | old_fs = get_fs(); | |
3483 | set_fs(KERNEL_DS); | |
3484 | ||
3485 | /* | |
3486 | * Flush the instruction cache, since we've played with text. | |
3487 | * Do it before processing of module parameters, so the module | |
3488 | * can provide parameter accessor functions of its own. | |
3489 | */ | |
7523e4dc RR |
3490 | if (mod->init_layout.base) |
3491 | flush_icache_range((unsigned long)mod->init_layout.base, | |
3492 | (unsigned long)mod->init_layout.base | |
3493 | + mod->init_layout.size); | |
3494 | flush_icache_range((unsigned long)mod->core_layout.base, | |
3495 | (unsigned long)mod->core_layout.base + mod->core_layout.size); | |
22e268eb RR |
3496 | |
3497 | set_fs(old_fs); | |
3498 | } | |
3499 | ||
74e08fcf JB |
3500 | int __weak module_frob_arch_sections(Elf_Ehdr *hdr, |
3501 | Elf_Shdr *sechdrs, | |
3502 | char *secstrings, | |
3503 | struct module *mod) | |
3504 | { | |
3505 | return 0; | |
3506 | } | |
3507 | ||
be7de5f9 PB |
3508 | /* module_blacklist is a comma-separated list of module names */ |
3509 | static char *module_blacklist; | |
96b5b194 | 3510 | static bool blacklisted(const char *module_name) |
be7de5f9 PB |
3511 | { |
3512 | const char *p; | |
3513 | size_t len; | |
3514 | ||
3515 | if (!module_blacklist) | |
3516 | return false; | |
3517 | ||
3518 | for (p = module_blacklist; *p; p += len) { | |
3519 | len = strcspn(p, ","); | |
3520 | if (strlen(module_name) == len && !memcmp(module_name, p, len)) | |
3521 | return true; | |
3522 | if (p[len] == ',') | |
3523 | len++; | |
3524 | } | |
3525 | return false; | |
3526 | } | |
3527 | core_param(module_blacklist, module_blacklist, charp, 0400); | |
3528 | ||
2f3238ae | 3529 | static struct module *layout_and_allocate(struct load_info *info, int flags) |
1da177e4 | 3530 | { |
1da177e4 | 3531 | struct module *mod; |
444d13ff | 3532 | unsigned int ndx; |
d913188c | 3533 | int err; |
3ae91c21 | 3534 | |
81a0abd9 | 3535 | err = check_modinfo(info->mod, info, flags); |
40dd2560 RR |
3536 | if (err) |
3537 | return ERR_PTR(err); | |
1da177e4 | 3538 | |
1da177e4 | 3539 | /* Allow arches to frob section contents and sizes. */ |
49668688 | 3540 | err = module_frob_arch_sections(info->hdr, info->sechdrs, |
81a0abd9 | 3541 | info->secstrings, info->mod); |
1da177e4 | 3542 | if (err < 0) |
8d8022e8 | 3543 | return ERR_PTR(err); |
1da177e4 | 3544 | |
8d8022e8 RR |
3545 | /* We will do a special allocation for per-cpu sections later. */ |
3546 | info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
1da177e4 | 3547 | |
444d13ff JY |
3548 | /* |
3549 | * Mark ro_after_init section with SHF_RO_AFTER_INIT so that | |
3550 | * layout_sections() can put it in the right place. | |
3551 | * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set. | |
3552 | */ | |
3553 | ndx = find_sec(info, ".data..ro_after_init"); | |
e872267b AB |
3554 | if (ndx) |
3555 | info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT; | |
3556 | /* | |
3557 | * Mark the __jump_table section as ro_after_init as well: these data | |
3558 | * structures are never modified, with the exception of entries that | |
3559 | * refer to code in the __init section, which are annotated as such | |
3560 | * at module load time. | |
3561 | */ | |
3562 | ndx = find_sec(info, "__jump_table"); | |
444d13ff JY |
3563 | if (ndx) |
3564 | info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT; | |
3565 | ||
1da177e4 LT |
3566 | /* Determine total sizes, and put offsets in sh_entsize. For now |
3567 | this is done generically; there doesn't appear to be any | |
3568 | special cases for the architectures. */ | |
81a0abd9 JY |
3569 | layout_sections(info->mod, info); |
3570 | layout_symtab(info->mod, info); | |
1da177e4 | 3571 | |
65b8a9b4 | 3572 | /* Allocate and move to the final place */ |
81a0abd9 | 3573 | err = move_module(info->mod, info); |
d913188c | 3574 | if (err) |
8d8022e8 | 3575 | return ERR_PTR(err); |
d913188c RR |
3576 | |
3577 | /* Module has been copied to its final place now: return it. */ | |
3578 | mod = (void *)info->sechdrs[info->index.mod].sh_addr; | |
49668688 | 3579 | kmemleak_load_module(mod, info); |
d913188c | 3580 | return mod; |
d913188c RR |
3581 | } |
3582 | ||
3583 | /* mod is no longer valid after this! */ | |
3584 | static void module_deallocate(struct module *mod, struct load_info *info) | |
3585 | { | |
d913188c | 3586 | percpu_modfree(mod); |
d453cded | 3587 | module_arch_freeing_init(mod); |
7523e4dc RR |
3588 | module_memfree(mod->init_layout.base); |
3589 | module_memfree(mod->core_layout.base); | |
d913188c RR |
3590 | } |
3591 | ||
74e08fcf JB |
3592 | int __weak module_finalize(const Elf_Ehdr *hdr, |
3593 | const Elf_Shdr *sechdrs, | |
3594 | struct module *me) | |
3595 | { | |
3596 | return 0; | |
3597 | } | |
3598 | ||
811d66a0 RR |
3599 | static int post_relocation(struct module *mod, const struct load_info *info) |
3600 | { | |
51f3d0f4 | 3601 | /* Sort exception table now relocations are done. */ |
811d66a0 RR |
3602 | sort_extable(mod->extable, mod->extable + mod->num_exentries); |
3603 | ||
3604 | /* Copy relocated percpu area over. */ | |
3605 | percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr, | |
3606 | info->sechdrs[info->index.pcpu].sh_size); | |
3607 | ||
51f3d0f4 | 3608 | /* Setup kallsyms-specific fields. */ |
811d66a0 RR |
3609 | add_kallsyms(mod, info); |
3610 | ||
3611 | /* Arch-specific module finalizing. */ | |
3612 | return module_finalize(info->hdr, info->sechdrs, mod); | |
3613 | } | |
3614 | ||
9bb9c3be RR |
3615 | /* Is this module of this name done loading? No locks held. */ |
3616 | static bool finished_loading(const char *name) | |
3617 | { | |
3618 | struct module *mod; | |
3619 | bool ret; | |
3620 | ||
9cc019b8 PZ |
3621 | /* |
3622 | * The module_mutex should not be a heavily contended lock; | |
3623 | * if we get the occasional sleep here, we'll go an extra iteration | |
3624 | * in the wait_event_interruptible(), which is harmless. | |
3625 | */ | |
3626 | sched_annotate_sleep(); | |
9bb9c3be | 3627 | mutex_lock(&module_mutex); |
4f6de4d5 | 3628 | mod = find_module_all(name, strlen(name), true); |
6e6de3de | 3629 | ret = !mod || mod->state == MODULE_STATE_LIVE; |
9bb9c3be RR |
3630 | mutex_unlock(&module_mutex); |
3631 | ||
3632 | return ret; | |
3633 | } | |
3634 | ||
34e1169d KC |
3635 | /* Call module constructors. */ |
3636 | static void do_mod_ctors(struct module *mod) | |
3637 | { | |
3638 | #ifdef CONFIG_CONSTRUCTORS | |
3639 | unsigned long i; | |
3640 | ||
3641 | for (i = 0; i < mod->num_ctors; i++) | |
3642 | mod->ctors[i](); | |
3643 | #endif | |
3644 | } | |
3645 | ||
c7496379 RR |
3646 | /* For freeing module_init on success, in case kallsyms traversing */ |
3647 | struct mod_initfree { | |
1a7b7d92 | 3648 | struct llist_node node; |
c7496379 RR |
3649 | void *module_init; |
3650 | }; | |
3651 | ||
1a7b7d92 | 3652 | static void do_free_init(struct work_struct *w) |
c7496379 | 3653 | { |
1a7b7d92 RE |
3654 | struct llist_node *pos, *n, *list; |
3655 | struct mod_initfree *initfree; | |
3656 | ||
3657 | list = llist_del_all(&init_free_list); | |
3658 | ||
3659 | synchronize_rcu(); | |
3660 | ||
3661 | llist_for_each_safe(pos, n, list) { | |
3662 | initfree = container_of(pos, struct mod_initfree, node); | |
3663 | module_memfree(initfree->module_init); | |
3664 | kfree(initfree); | |
3665 | } | |
c7496379 RR |
3666 | } |
3667 | ||
be02a186 JK |
3668 | /* |
3669 | * This is where the real work happens. | |
3670 | * | |
3671 | * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb | |
3672 | * helper command 'lx-symbols'. | |
3673 | */ | |
3674 | static noinline int do_init_module(struct module *mod) | |
34e1169d KC |
3675 | { |
3676 | int ret = 0; | |
c7496379 RR |
3677 | struct mod_initfree *freeinit; |
3678 | ||
3679 | freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL); | |
3680 | if (!freeinit) { | |
3681 | ret = -ENOMEM; | |
3682 | goto fail; | |
3683 | } | |
7523e4dc | 3684 | freeinit->module_init = mod->init_layout.base; |
34e1169d | 3685 | |
34e1169d KC |
3686 | do_mod_ctors(mod); |
3687 | /* Start the module */ | |
3688 | if (mod->init != NULL) | |
3689 | ret = do_one_initcall(mod->init); | |
3690 | if (ret < 0) { | |
c7496379 | 3691 | goto fail_free_freeinit; |
34e1169d KC |
3692 | } |
3693 | if (ret > 0) { | |
bddb12b3 AM |
3694 | pr_warn("%s: '%s'->init suspiciously returned %d, it should " |
3695 | "follow 0/-E convention\n" | |
3696 | "%s: loading module anyway...\n", | |
3697 | __func__, mod->name, ret, __func__); | |
34e1169d KC |
3698 | dump_stack(); |
3699 | } | |
3700 | ||
3701 | /* Now it's a first class citizen! */ | |
3702 | mod->state = MODULE_STATE_LIVE; | |
3703 | blocking_notifier_call_chain(&module_notify_list, | |
3704 | MODULE_STATE_LIVE, mod); | |
3705 | ||
c67a46e0 JY |
3706 | /* Delay uevent until module has finished its init routine */ |
3707 | kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD); | |
3708 | ||
774a1221 TH |
3709 | /* |
3710 | * We need to finish all async code before the module init sequence | |
456fc459 IP |
3711 | * is done. This has potential to deadlock if synchronous module |
3712 | * loading is requested from async (which is not allowed!). | |
774a1221 | 3713 | * |
456fc459 IP |
3714 | * See commit 0fdff3ec6d87 ("async, kmod: warn on synchronous |
3715 | * request_module() from async workers") for more details. | |
774a1221 | 3716 | */ |
456fc459 | 3717 | if (!mod->async_probe_requested) |
774a1221 | 3718 | async_synchronize_full(); |
34e1169d | 3719 | |
aba4b5c2 | 3720 | ftrace_free_mem(mod, mod->init_layout.base, mod->init_layout.base + |
3e234289 | 3721 | mod->init_layout.size); |
34e1169d KC |
3722 | mutex_lock(&module_mutex); |
3723 | /* Drop initial reference. */ | |
3724 | module_put(mod); | |
3725 | trim_init_extable(mod); | |
3726 | #ifdef CONFIG_KALLSYMS | |
8244062e RR |
3727 | /* Switch to core kallsyms now init is done: kallsyms may be walking! */ |
3728 | rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms); | |
34e1169d | 3729 | #endif |
444d13ff | 3730 | module_enable_ro(mod, true); |
93c2e105 | 3731 | mod_tree_remove_init(mod); |
d453cded | 3732 | module_arch_freeing_init(mod); |
7523e4dc RR |
3733 | mod->init_layout.base = NULL; |
3734 | mod->init_layout.size = 0; | |
3735 | mod->init_layout.ro_size = 0; | |
444d13ff | 3736 | mod->init_layout.ro_after_init_size = 0; |
7523e4dc | 3737 | mod->init_layout.text_size = 0; |
c7496379 RR |
3738 | /* |
3739 | * We want to free module_init, but be aware that kallsyms may be | |
0be964be | 3740 | * walking this with preempt disabled. In all the failure paths, we |
cb2f5536 | 3741 | * call synchronize_rcu(), but we don't want to slow down the success |
1a7b7d92 RE |
3742 | * path. module_memfree() cannot be called in an interrupt, so do the |
3743 | * work and call synchronize_rcu() in a work queue. | |
3744 | * | |
ae646f0b JH |
3745 | * Note that module_alloc() on most architectures creates W+X page |
3746 | * mappings which won't be cleaned up until do_free_init() runs. Any | |
3747 | * code such as mark_rodata_ro() which depends on those mappings to | |
3748 | * be cleaned up needs to sync with the queued work - ie | |
cb2f5536 | 3749 | * rcu_barrier() |
c7496379 | 3750 | */ |
1a7b7d92 RE |
3751 | if (llist_add(&freeinit->node, &init_free_list)) |
3752 | schedule_work(&init_free_wq); | |
3753 | ||
34e1169d KC |
3754 | mutex_unlock(&module_mutex); |
3755 | wake_up_all(&module_wq); | |
3756 | ||
3757 | return 0; | |
c7496379 RR |
3758 | |
3759 | fail_free_freeinit: | |
3760 | kfree(freeinit); | |
3761 | fail: | |
3762 | /* Try to protect us from buggy refcounters. */ | |
3763 | mod->state = MODULE_STATE_GOING; | |
cb2f5536 | 3764 | synchronize_rcu(); |
c7496379 RR |
3765 | module_put(mod); |
3766 | blocking_notifier_call_chain(&module_notify_list, | |
3767 | MODULE_STATE_GOING, mod); | |
7e545d6e | 3768 | klp_module_going(mod); |
7dcd182b | 3769 | ftrace_release_mod(mod); |
c7496379 RR |
3770 | free_module(mod); |
3771 | wake_up_all(&module_wq); | |
3772 | return ret; | |
34e1169d KC |
3773 | } |
3774 | ||
3775 | static int may_init_module(void) | |
3776 | { | |
3777 | if (!capable(CAP_SYS_MODULE) || modules_disabled) | |
3778 | return -EPERM; | |
3779 | ||
3780 | return 0; | |
3781 | } | |
3782 | ||
a3535c7e RR |
3783 | /* |
3784 | * We try to place it in the list now to make sure it's unique before | |
3785 | * we dedicate too many resources. In particular, temporary percpu | |
3786 | * memory exhaustion. | |
3787 | */ | |
3788 | static int add_unformed_module(struct module *mod) | |
3789 | { | |
3790 | int err; | |
3791 | struct module *old; | |
3792 | ||
3793 | mod->state = MODULE_STATE_UNFORMED; | |
3794 | ||
3795 | again: | |
3796 | mutex_lock(&module_mutex); | |
4f6de4d5 MK |
3797 | old = find_module_all(mod->name, strlen(mod->name), true); |
3798 | if (old != NULL) { | |
6e6de3de | 3799 | if (old->state != MODULE_STATE_LIVE) { |
a3535c7e RR |
3800 | /* Wait in case it fails to load. */ |
3801 | mutex_unlock(&module_mutex); | |
9cc019b8 PZ |
3802 | err = wait_event_interruptible(module_wq, |
3803 | finished_loading(mod->name)); | |
a3535c7e RR |
3804 | if (err) |
3805 | goto out_unlocked; | |
3806 | goto again; | |
3807 | } | |
3808 | err = -EEXIST; | |
3809 | goto out; | |
3810 | } | |
4f666546 | 3811 | mod_update_bounds(mod); |
a3535c7e | 3812 | list_add_rcu(&mod->list, &modules); |
93c2e105 | 3813 | mod_tree_insert(mod); |
a3535c7e RR |
3814 | err = 0; |
3815 | ||
3816 | out: | |
3817 | mutex_unlock(&module_mutex); | |
3818 | out_unlocked: | |
3819 | return err; | |
3820 | } | |
3821 | ||
3822 | static int complete_formation(struct module *mod, struct load_info *info) | |
3823 | { | |
3824 | int err; | |
3825 | ||
3826 | mutex_lock(&module_mutex); | |
3827 | ||
3828 | /* Find duplicate symbols (must be called under lock). */ | |
2d25bc55 | 3829 | err = verify_exported_symbols(mod); |
a3535c7e RR |
3830 | if (err < 0) |
3831 | goto out; | |
3832 | ||
3833 | /* This relies on module_mutex for list integrity. */ | |
3834 | module_bug_finalize(info->hdr, info->sechdrs, mod); | |
3835 | ||
444d13ff | 3836 | module_enable_ro(mod, false); |
85c898db | 3837 | module_enable_nx(mod); |
88bf1c6d | 3838 | module_enable_x(mod); |
4982223e | 3839 | |
a3535c7e RR |
3840 | /* Mark state as coming so strong_try_module_get() ignores us, |
3841 | * but kallsyms etc. can see us. */ | |
3842 | mod->state = MODULE_STATE_COMING; | |
4982223e RR |
3843 | mutex_unlock(&module_mutex); |
3844 | ||
4982223e | 3845 | return 0; |
a3535c7e RR |
3846 | |
3847 | out: | |
3848 | mutex_unlock(&module_mutex); | |
3849 | return err; | |
3850 | } | |
3851 | ||
4c973d16 JY |
3852 | static int prepare_coming_module(struct module *mod) |
3853 | { | |
7e545d6e JY |
3854 | int err; |
3855 | ||
4c973d16 | 3856 | ftrace_module_enable(mod); |
7e545d6e JY |
3857 | err = klp_module_coming(mod); |
3858 | if (err) | |
3859 | return err; | |
3860 | ||
4c973d16 JY |
3861 | blocking_notifier_call_chain(&module_notify_list, |
3862 | MODULE_STATE_COMING, mod); | |
3863 | return 0; | |
3864 | } | |
3865 | ||
ecc86170 LR |
3866 | static int unknown_module_param_cb(char *param, char *val, const char *modname, |
3867 | void *arg) | |
54041d8a | 3868 | { |
f2411da7 LR |
3869 | struct module *mod = arg; |
3870 | int ret; | |
3871 | ||
3872 | if (strcmp(param, "async_probe") == 0) { | |
3873 | mod->async_probe_requested = true; | |
3874 | return 0; | |
3875 | } | |
3876 | ||
6da0b565 | 3877 | /* Check for magic 'dyndbg' arg */ |
f2411da7 | 3878 | ret = ddebug_dyndbg_module_param_cb(param, val, modname); |
bddb12b3 AM |
3879 | if (ret != 0) |
3880 | pr_warn("%s: unknown parameter '%s' ignored\n", modname, param); | |
54041d8a RR |
3881 | return 0; |
3882 | } | |
3883 | ||
d913188c RR |
3884 | /* Allocate and load the module: note that size of section 0 is always |
3885 | zero, and we rely on this for optional sections. */ | |
2f3238ae RR |
3886 | static int load_module(struct load_info *info, const char __user *uargs, |
3887 | int flags) | |
d913188c | 3888 | { |
a3535c7e | 3889 | struct module *mod; |
5fdc7db6 | 3890 | long err = 0; |
51e158c1 | 3891 | char *after_dashes; |
d913188c | 3892 | |
c40724b7 FL |
3893 | /* |
3894 | * Do the signature check (if any) first. All that | |
3895 | * the signature check needs is info->len, it does | |
3896 | * not need any of the section info. That can be | |
3897 | * set up later. This will minimize the chances | |
3898 | * of a corrupt module causing problems before | |
3899 | * we even get to the signature check. | |
3900 | * | |
3901 | * The check will also adjust info->len by stripping | |
3902 | * off the sig length at the end of the module, making | |
3903 | * checks against info->len more correct. | |
3904 | */ | |
3905 | err = module_sig_check(info, flags); | |
5fdc7db6 JY |
3906 | if (err) |
3907 | goto free_copy; | |
3908 | ||
c40724b7 FL |
3909 | /* |
3910 | * Do basic sanity checks against the ELF header and | |
3911 | * sections. | |
3912 | */ | |
3913 | err = elf_validity_check(info); | |
3914 | if (err) { | |
3915 | pr_err("Module has invalid ELF structures\n"); | |
3916 | goto free_copy; | |
3917 | } | |
3918 | ||
3919 | /* | |
3920 | * Everything checks out, so set up the section info | |
3921 | * in the info structure. | |
3922 | */ | |
5fdc7db6 JY |
3923 | err = setup_load_info(info, flags); |
3924 | if (err) | |
3925 | goto free_copy; | |
3926 | ||
c40724b7 FL |
3927 | /* |
3928 | * Now that we know we have the correct module name, check | |
3929 | * if it's blacklisted. | |
3930 | */ | |
5fdc7db6 JY |
3931 | if (blacklisted(info->name)) { |
3932 | err = -EPERM; | |
3933 | goto free_copy; | |
3934 | } | |
3935 | ||
5fdc7db6 | 3936 | err = rewrite_section_headers(info, flags); |
d913188c | 3937 | if (err) |
34e1169d | 3938 | goto free_copy; |
d913188c | 3939 | |
5fdc7db6 JY |
3940 | /* Check module struct version now, before we try to use module. */ |
3941 | if (!check_modstruct_version(info, info->mod)) { | |
3942 | err = -ENOEXEC; | |
3943 | goto free_copy; | |
3944 | } | |
3945 | ||
d913188c | 3946 | /* Figure out module layout, and allocate all the memory. */ |
2f3238ae | 3947 | mod = layout_and_allocate(info, flags); |
65b8a9b4 LT |
3948 | if (IS_ERR(mod)) { |
3949 | err = PTR_ERR(mod); | |
d913188c | 3950 | goto free_copy; |
1da177e4 | 3951 | } |
1da177e4 | 3952 | |
ca86cad7 RGB |
3953 | audit_log_kern_module(mod->name); |
3954 | ||
a3535c7e RR |
3955 | /* Reserve our place in the list. */ |
3956 | err = add_unformed_module(mod); | |
3957 | if (err) | |
1fb9341a | 3958 | goto free_module; |
1fb9341a | 3959 | |
106a4ee2 | 3960 | #ifdef CONFIG_MODULE_SIG |
34e1169d | 3961 | mod->sig_ok = info->sig_ok; |
64748a2c | 3962 | if (!mod->sig_ok) { |
bddb12b3 | 3963 | pr_notice_once("%s: module verification failed: signature " |
ab92ebbb | 3964 | "and/or required key missing - tainting " |
bddb12b3 | 3965 | "kernel\n", mod->name); |
66cc69e3 | 3966 | add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK); |
64748a2c | 3967 | } |
106a4ee2 RR |
3968 | #endif |
3969 | ||
8d8022e8 | 3970 | /* To avoid stressing percpu allocator, do this once we're unique. */ |
9eb76d77 | 3971 | err = percpu_modalloc(mod, info); |
8d8022e8 RR |
3972 | if (err) |
3973 | goto unlink_mod; | |
3974 | ||
49668688 | 3975 | /* Now module is in final location, initialize linked lists, etc. */ |
9f85a4bb RR |
3976 | err = module_unload_init(mod); |
3977 | if (err) | |
1fb9341a | 3978 | goto unlink_mod; |
1da177e4 | 3979 | |
cf2fde7b | 3980 | init_param_lock(mod); |
b51d23e4 | 3981 | |
22e268eb RR |
3982 | /* Now we've got everything in the final locations, we can |
3983 | * find optional sections. */ | |
eb3057df FH |
3984 | err = find_module_sections(mod, info); |
3985 | if (err) | |
3986 | goto free_unload; | |
9b37ccfc | 3987 | |
49668688 | 3988 | err = check_module_license_and_versions(mod); |
22e268eb RR |
3989 | if (err) |
3990 | goto free_unload; | |
9841d61d | 3991 | |
c988d2b2 | 3992 | /* Set up MODINFO_ATTR fields */ |
34e1169d | 3993 | setup_modinfo(mod, info); |
c988d2b2 | 3994 | |
1da177e4 | 3995 | /* Fix up syms, so that st_value is a pointer to location. */ |
34e1169d | 3996 | err = simplify_symbols(mod, info); |
1da177e4 | 3997 | if (err < 0) |
d913188c | 3998 | goto free_modinfo; |
1da177e4 | 3999 | |
34e1169d | 4000 | err = apply_relocations(mod, info); |
22e268eb | 4001 | if (err < 0) |
d913188c | 4002 | goto free_modinfo; |
1da177e4 | 4003 | |
34e1169d | 4004 | err = post_relocation(mod, info); |
1da177e4 | 4005 | if (err < 0) |
d913188c | 4006 | goto free_modinfo; |
1da177e4 | 4007 | |
22e268eb | 4008 | flush_module_icache(mod); |
378bac82 | 4009 | |
6526c534 RR |
4010 | /* Now copy in args */ |
4011 | mod->args = strndup_user(uargs, ~0UL >> 1); | |
4012 | if (IS_ERR(mod->args)) { | |
4013 | err = PTR_ERR(mod->args); | |
4014 | goto free_arch_cleanup; | |
4015 | } | |
8d3b33f6 | 4016 | |
52796312 | 4017 | dynamic_debug_setup(mod, info->debug, info->num_debug); |
ff49d74a | 4018 | |
a949ae56 SRRH |
4019 | /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */ |
4020 | ftrace_module_init(mod); | |
4021 | ||
a3535c7e RR |
4022 | /* Finally it's fully formed, ready to start executing. */ |
4023 | err = complete_formation(mod, info); | |
4024 | if (err) | |
1fb9341a | 4025 | goto ddebug_cleanup; |
be593f4c | 4026 | |
4c973d16 JY |
4027 | err = prepare_coming_module(mod); |
4028 | if (err) | |
4029 | goto bug_cleanup; | |
4030 | ||
51f3d0f4 | 4031 | /* Module is ready to execute: parsing args may do that. */ |
51e158c1 | 4032 | after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, |
4355efbd | 4033 | -32768, 32767, mod, |
ecc86170 | 4034 | unknown_module_param_cb); |
51e158c1 RR |
4035 | if (IS_ERR(after_dashes)) { |
4036 | err = PTR_ERR(after_dashes); | |
4c973d16 | 4037 | goto coming_cleanup; |
51e158c1 RR |
4038 | } else if (after_dashes) { |
4039 | pr_warn("%s: parameters '%s' after `--' ignored\n", | |
4040 | mod->name, after_dashes); | |
4041 | } | |
1da177e4 | 4042 | |
ca86cad7 | 4043 | /* Link in to sysfs. */ |
34e1169d | 4044 | err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp); |
1da177e4 | 4045 | if (err < 0) |
4c973d16 | 4046 | goto coming_cleanup; |
80a3d1bb | 4047 | |
1ce15ef4 JY |
4048 | if (is_livepatch_module(mod)) { |
4049 | err = copy_module_elf(mod, info); | |
4050 | if (err < 0) | |
4051 | goto sysfs_cleanup; | |
4052 | } | |
4053 | ||
48fd1188 | 4054 | /* Get rid of temporary copy. */ |
34e1169d | 4055 | free_copy(info); |
1da177e4 LT |
4056 | |
4057 | /* Done! */ | |
51f3d0f4 | 4058 | trace_module_load(mod); |
34e1169d KC |
4059 | |
4060 | return do_init_module(mod); | |
1da177e4 | 4061 | |
1ce15ef4 JY |
4062 | sysfs_cleanup: |
4063 | mod_sysfs_teardown(mod); | |
4c973d16 | 4064 | coming_cleanup: |
885a78d4 | 4065 | mod->state = MODULE_STATE_GOING; |
a5544880 | 4066 | destroy_params(mod->kp, mod->num_kp); |
4c973d16 JY |
4067 | blocking_notifier_call_chain(&module_notify_list, |
4068 | MODULE_STATE_GOING, mod); | |
7e545d6e | 4069 | klp_module_going(mod); |
1fb9341a | 4070 | bug_cleanup: |
9e299019 | 4071 | mod->state = MODULE_STATE_GOING; |
1fb9341a | 4072 | /* module_bug_cleanup needs module_mutex protection */ |
75676500 | 4073 | mutex_lock(&module_mutex); |
5336377d | 4074 | module_bug_cleanup(mod); |
ee61abb3 | 4075 | mutex_unlock(&module_mutex); |
ff7e0055 | 4076 | |
a3535c7e | 4077 | ddebug_cleanup: |
1323eac7 | 4078 | ftrace_release_mod(mod); |
52796312 | 4079 | dynamic_debug_remove(mod, info->debug); |
cb2f5536 | 4080 | synchronize_rcu(); |
6526c534 RR |
4081 | kfree(mod->args); |
4082 | free_arch_cleanup: | |
1da177e4 | 4083 | module_arch_cleanup(mod); |
d913188c | 4084 | free_modinfo: |
a263f776 | 4085 | free_modinfo(mod); |
22e268eb | 4086 | free_unload: |
1da177e4 | 4087 | module_unload_free(mod); |
1fb9341a RR |
4088 | unlink_mod: |
4089 | mutex_lock(&module_mutex); | |
4090 | /* Unlink carefully: kallsyms could be walking list. */ | |
4091 | list_del_rcu(&mod->list); | |
758556bd | 4092 | mod_tree_remove(mod); |
1fb9341a | 4093 | wake_up_all(&module_wq); |
0be964be | 4094 | /* Wait for RCU-sched synchronizing before releasing mod->list. */ |
cb2f5536 | 4095 | synchronize_rcu(); |
1fb9341a | 4096 | mutex_unlock(&module_mutex); |
d913188c | 4097 | free_module: |
35a9393c | 4098 | /* Free lock-classes; relies on the preceding sync_rcu() */ |
7523e4dc | 4099 | lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size); |
35a9393c | 4100 | |
34e1169d | 4101 | module_deallocate(mod, info); |
d913188c | 4102 | free_copy: |
34e1169d KC |
4103 | free_copy(info); |
4104 | return err; | |
b99b87f7 PO |
4105 | } |
4106 | ||
17da2bd9 HC |
4107 | SYSCALL_DEFINE3(init_module, void __user *, umod, |
4108 | unsigned long, len, const char __user *, uargs) | |
1da177e4 | 4109 | { |
34e1169d KC |
4110 | int err; |
4111 | struct load_info info = { }; | |
1da177e4 | 4112 | |
34e1169d KC |
4113 | err = may_init_module(); |
4114 | if (err) | |
4115 | return err; | |
1da177e4 | 4116 | |
34e1169d KC |
4117 | pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n", |
4118 | umod, len, uargs); | |
1da177e4 | 4119 | |
34e1169d KC |
4120 | err = copy_module_from_user(umod, len, &info); |
4121 | if (err) | |
4122 | return err; | |
1da177e4 | 4123 | |
2f3238ae | 4124 | return load_module(&info, uargs, 0); |
34e1169d | 4125 | } |
94462ad3 | 4126 | |
2f3238ae | 4127 | SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) |
34e1169d | 4128 | { |
34e1169d | 4129 | struct load_info info = { }; |
a1db7420 MZ |
4130 | loff_t size; |
4131 | void *hdr; | |
4132 | int err; | |
94462ad3 | 4133 | |
34e1169d KC |
4134 | err = may_init_module(); |
4135 | if (err) | |
4136 | return err; | |
1da177e4 | 4137 | |
2f3238ae | 4138 | pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags); |
6c5db22d | 4139 | |
2f3238ae RR |
4140 | if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS |
4141 | |MODULE_INIT_IGNORE_VERMAGIC)) | |
4142 | return -EINVAL; | |
d6de2c80 | 4143 | |
a1db7420 MZ |
4144 | err = kernel_read_file_from_fd(fd, &hdr, &size, INT_MAX, |
4145 | READING_MODULE); | |
34e1169d KC |
4146 | if (err) |
4147 | return err; | |
a1db7420 MZ |
4148 | info.hdr = hdr; |
4149 | info.len = size; | |
1da177e4 | 4150 | |
2f3238ae | 4151 | return load_module(&info, uargs, flags); |
1da177e4 LT |
4152 | } |
4153 | ||
4154 | static inline int within(unsigned long addr, void *start, unsigned long size) | |
4155 | { | |
4156 | return ((void *)addr >= start && (void *)addr < start + size); | |
4157 | } | |
4158 | ||
4159 | #ifdef CONFIG_KALLSYMS | |
4160 | /* | |
4161 | * This ignores the intensely annoying "mapping symbols" found | |
4162 | * in ARM ELF files: $a, $t and $d. | |
4163 | */ | |
4164 | static inline int is_arm_mapping_symbol(const char *str) | |
4165 | { | |
2e3a10a1 RK |
4166 | if (str[0] == '.' && str[1] == 'L') |
4167 | return true; | |
6c34f1f5 | 4168 | return str[0] == '$' && strchr("axtd", str[1]) |
1da177e4 LT |
4169 | && (str[2] == '\0' || str[2] == '.'); |
4170 | } | |
4171 | ||
2d25bc55 | 4172 | static const char *kallsyms_symbol_name(struct mod_kallsyms *kallsyms, unsigned int symnum) |
2e7bac53 | 4173 | { |
8244062e | 4174 | return kallsyms->strtab + kallsyms->symtab[symnum].st_name; |
2e7bac53 RR |
4175 | } |
4176 | ||
2d25bc55 JY |
4177 | /* |
4178 | * Given a module and address, find the corresponding symbol and return its name | |
4179 | * while providing its size and offset if needed. | |
4180 | */ | |
4181 | static const char *find_kallsyms_symbol(struct module *mod, | |
4182 | unsigned long addr, | |
4183 | unsigned long *size, | |
4184 | unsigned long *offset) | |
1da177e4 LT |
4185 | { |
4186 | unsigned int i, best = 0; | |
93d77e7f | 4187 | unsigned long nextval, bestval; |
8244062e | 4188 | struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); |
1da177e4 LT |
4189 | |
4190 | /* At worse, next value is at end of module */ | |
a06f6211 | 4191 | if (within_module_init(addr, mod)) |
7523e4dc | 4192 | nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size; |
22a8bdeb | 4193 | else |
7523e4dc | 4194 | nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size; |
1da177e4 | 4195 | |
93d77e7f VW |
4196 | bestval = kallsyms_symbol_value(&kallsyms->symtab[best]); |
4197 | ||
25985edc | 4198 | /* Scan for closest preceding symbol, and next symbol. (ELF |
22a8bdeb | 4199 | starts real symbols at 1). */ |
8244062e | 4200 | for (i = 1; i < kallsyms->num_symtab; i++) { |
93d77e7f VW |
4201 | const Elf_Sym *sym = &kallsyms->symtab[i]; |
4202 | unsigned long thisval = kallsyms_symbol_value(sym); | |
4203 | ||
4204 | if (sym->st_shndx == SHN_UNDEF) | |
1da177e4 LT |
4205 | continue; |
4206 | ||
4207 | /* We ignore unnamed symbols: they're uninformative | |
4208 | * and inserted at a whim. */ | |
2d25bc55 JY |
4209 | if (*kallsyms_symbol_name(kallsyms, i) == '\0' |
4210 | || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms, i))) | |
2e7bac53 RR |
4211 | continue; |
4212 | ||
93d77e7f | 4213 | if (thisval <= addr && thisval > bestval) { |
1da177e4 | 4214 | best = i; |
93d77e7f VW |
4215 | bestval = thisval; |
4216 | } | |
4217 | if (thisval > addr && thisval < nextval) | |
4218 | nextval = thisval; | |
1da177e4 LT |
4219 | } |
4220 | ||
4221 | if (!best) | |
4222 | return NULL; | |
4223 | ||
ffb45122 | 4224 | if (size) |
93d77e7f | 4225 | *size = nextval - bestval; |
ffb45122 | 4226 | if (offset) |
93d77e7f | 4227 | *offset = addr - bestval; |
2d25bc55 JY |
4228 | |
4229 | return kallsyms_symbol_name(kallsyms, best); | |
1da177e4 LT |
4230 | } |
4231 | ||
b865ea64 SS |
4232 | void * __weak dereference_module_function_descriptor(struct module *mod, |
4233 | void *ptr) | |
4234 | { | |
4235 | return ptr; | |
4236 | } | |
4237 | ||
6dd06c9f RR |
4238 | /* For kallsyms to ask for address resolution. NULL means not found. Careful |
4239 | * not to lock to avoid deadlock on oopses, simply disable preemption. */ | |
92dfc9dc | 4240 | const char *module_address_lookup(unsigned long addr, |
6dd06c9f RR |
4241 | unsigned long *size, |
4242 | unsigned long *offset, | |
4243 | char **modname, | |
4244 | char *namebuf) | |
1da177e4 | 4245 | { |
cb2a5205 | 4246 | const char *ret = NULL; |
b7df4d1b | 4247 | struct module *mod; |
1da177e4 | 4248 | |
cb2a5205 | 4249 | preempt_disable(); |
b7df4d1b PZ |
4250 | mod = __module_address(addr); |
4251 | if (mod) { | |
4252 | if (modname) | |
4253 | *modname = mod->name; | |
2d25bc55 JY |
4254 | |
4255 | ret = find_kallsyms_symbol(mod, addr, size, offset); | |
1da177e4 | 4256 | } |
6dd06c9f RR |
4257 | /* Make a copy in here where it's safe */ |
4258 | if (ret) { | |
4259 | strncpy(namebuf, ret, KSYM_NAME_LEN - 1); | |
4260 | ret = namebuf; | |
4261 | } | |
cb2a5205 | 4262 | preempt_enable(); |
b7df4d1b | 4263 | |
92dfc9dc | 4264 | return ret; |
1da177e4 LT |
4265 | } |
4266 | ||
9d65cb4a AD |
4267 | int lookup_module_symbol_name(unsigned long addr, char *symname) |
4268 | { | |
4269 | struct module *mod; | |
4270 | ||
cb2a5205 | 4271 | preempt_disable(); |
d72b3751 | 4272 | list_for_each_entry_rcu(mod, &modules, list) { |
0d21b0e3 RR |
4273 | if (mod->state == MODULE_STATE_UNFORMED) |
4274 | continue; | |
9b20a352 | 4275 | if (within_module(addr, mod)) { |
9d65cb4a AD |
4276 | const char *sym; |
4277 | ||
2d25bc55 | 4278 | sym = find_kallsyms_symbol(mod, addr, NULL, NULL); |
9d65cb4a AD |
4279 | if (!sym) |
4280 | goto out; | |
2d25bc55 | 4281 | |
9281acea | 4282 | strlcpy(symname, sym, KSYM_NAME_LEN); |
cb2a5205 | 4283 | preempt_enable(); |
9d65cb4a AD |
4284 | return 0; |
4285 | } | |
4286 | } | |
4287 | out: | |
cb2a5205 | 4288 | preempt_enable(); |
9d65cb4a AD |
4289 | return -ERANGE; |
4290 | } | |
4291 | ||
a5c43dae AD |
4292 | int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, |
4293 | unsigned long *offset, char *modname, char *name) | |
4294 | { | |
4295 | struct module *mod; | |
4296 | ||
cb2a5205 | 4297 | preempt_disable(); |
d72b3751 | 4298 | list_for_each_entry_rcu(mod, &modules, list) { |
0d21b0e3 RR |
4299 | if (mod->state == MODULE_STATE_UNFORMED) |
4300 | continue; | |
9b20a352 | 4301 | if (within_module(addr, mod)) { |
a5c43dae AD |
4302 | const char *sym; |
4303 | ||
2d25bc55 | 4304 | sym = find_kallsyms_symbol(mod, addr, size, offset); |
a5c43dae AD |
4305 | if (!sym) |
4306 | goto out; | |
4307 | if (modname) | |
9281acea | 4308 | strlcpy(modname, mod->name, MODULE_NAME_LEN); |
a5c43dae | 4309 | if (name) |
9281acea | 4310 | strlcpy(name, sym, KSYM_NAME_LEN); |
cb2a5205 | 4311 | preempt_enable(); |
a5c43dae AD |
4312 | return 0; |
4313 | } | |
4314 | } | |
4315 | out: | |
cb2a5205 | 4316 | preempt_enable(); |
a5c43dae AD |
4317 | return -ERANGE; |
4318 | } | |
4319 | ||
ea07890a AD |
4320 | int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, |
4321 | char *name, char *module_name, int *exported) | |
1da177e4 LT |
4322 | { |
4323 | struct module *mod; | |
4324 | ||
cb2a5205 | 4325 | preempt_disable(); |
d72b3751 | 4326 | list_for_each_entry_rcu(mod, &modules, list) { |
8244062e RR |
4327 | struct mod_kallsyms *kallsyms; |
4328 | ||
0d21b0e3 RR |
4329 | if (mod->state == MODULE_STATE_UNFORMED) |
4330 | continue; | |
8244062e RR |
4331 | kallsyms = rcu_dereference_sched(mod->kallsyms); |
4332 | if (symnum < kallsyms->num_symtab) { | |
93d77e7f VW |
4333 | const Elf_Sym *sym = &kallsyms->symtab[symnum]; |
4334 | ||
4335 | *value = kallsyms_symbol_value(sym); | |
1c7651f4 | 4336 | *type = kallsyms->typetab[symnum]; |
2d25bc55 | 4337 | strlcpy(name, kallsyms_symbol_name(kallsyms, symnum), KSYM_NAME_LEN); |
9281acea | 4338 | strlcpy(module_name, mod->name, MODULE_NAME_LEN); |
ca4787b7 | 4339 | *exported = is_exported(name, *value, mod); |
cb2a5205 | 4340 | preempt_enable(); |
ea07890a | 4341 | return 0; |
1da177e4 | 4342 | } |
8244062e | 4343 | symnum -= kallsyms->num_symtab; |
1da177e4 | 4344 | } |
cb2a5205 | 4345 | preempt_enable(); |
ea07890a | 4346 | return -ERANGE; |
1da177e4 LT |
4347 | } |
4348 | ||
2d25bc55 JY |
4349 | /* Given a module and name of symbol, find and return the symbol's value */ |
4350 | static unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name) | |
1da177e4 LT |
4351 | { |
4352 | unsigned int i; | |
8244062e | 4353 | struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); |
1da177e4 | 4354 | |
93d77e7f VW |
4355 | for (i = 0; i < kallsyms->num_symtab; i++) { |
4356 | const Elf_Sym *sym = &kallsyms->symtab[i]; | |
4357 | ||
2d25bc55 | 4358 | if (strcmp(name, kallsyms_symbol_name(kallsyms, i)) == 0 && |
93d77e7f VW |
4359 | sym->st_shndx != SHN_UNDEF) |
4360 | return kallsyms_symbol_value(sym); | |
4361 | } | |
1da177e4 LT |
4362 | return 0; |
4363 | } | |
4364 | ||
4365 | /* Look for this name: can be of form module:name. */ | |
4366 | unsigned long module_kallsyms_lookup_name(const char *name) | |
4367 | { | |
4368 | struct module *mod; | |
4369 | char *colon; | |
4370 | unsigned long ret = 0; | |
4371 | ||
4372 | /* Don't lock: we're in enough trouble already. */ | |
cb2a5205 | 4373 | preempt_disable(); |
17586188 | 4374 | if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) { |
4f6de4d5 | 4375 | if ((mod = find_module_all(name, colon - name, false)) != NULL) |
2d25bc55 | 4376 | ret = find_kallsyms_symbol_value(mod, colon+1); |
1da177e4 | 4377 | } else { |
0d21b0e3 RR |
4378 | list_for_each_entry_rcu(mod, &modules, list) { |
4379 | if (mod->state == MODULE_STATE_UNFORMED) | |
4380 | continue; | |
2d25bc55 | 4381 | if ((ret = find_kallsyms_symbol_value(mod, name)) != 0) |
1da177e4 | 4382 | break; |
0d21b0e3 | 4383 | } |
1da177e4 | 4384 | } |
cb2a5205 | 4385 | preempt_enable(); |
1da177e4 LT |
4386 | return ret; |
4387 | } | |
75a66614 AK |
4388 | |
4389 | int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, | |
4390 | struct module *, unsigned long), | |
4391 | void *data) | |
4392 | { | |
4393 | struct module *mod; | |
4394 | unsigned int i; | |
4395 | int ret; | |
4396 | ||
0be964be PZ |
4397 | module_assert_mutex(); |
4398 | ||
75a66614 | 4399 | list_for_each_entry(mod, &modules, list) { |
8244062e RR |
4400 | /* We hold module_mutex: no need for rcu_dereference_sched */ |
4401 | struct mod_kallsyms *kallsyms = mod->kallsyms; | |
4402 | ||
0d21b0e3 RR |
4403 | if (mod->state == MODULE_STATE_UNFORMED) |
4404 | continue; | |
8244062e | 4405 | for (i = 0; i < kallsyms->num_symtab; i++) { |
93d77e7f | 4406 | const Elf_Sym *sym = &kallsyms->symtab[i]; |
9f2d1e68 | 4407 | |
93d77e7f | 4408 | if (sym->st_shndx == SHN_UNDEF) |
9f2d1e68 JY |
4409 | continue; |
4410 | ||
2d25bc55 | 4411 | ret = fn(data, kallsyms_symbol_name(kallsyms, i), |
93d77e7f | 4412 | mod, kallsyms_symbol_value(sym)); |
75a66614 AK |
4413 | if (ret != 0) |
4414 | return ret; | |
4415 | } | |
4416 | } | |
4417 | return 0; | |
4418 | } | |
1da177e4 LT |
4419 | #endif /* CONFIG_KALLSYMS */ |
4420 | ||
7fd8329b PM |
4421 | /* Maximum number of characters written by module_flags() */ |
4422 | #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) | |
4423 | ||
4424 | /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */ | |
21aa9280 | 4425 | static char *module_flags(struct module *mod, char *buf) |
fa3ba2e8 FM |
4426 | { |
4427 | int bx = 0; | |
4428 | ||
0d21b0e3 | 4429 | BUG_ON(mod->state == MODULE_STATE_UNFORMED); |
21aa9280 AV |
4430 | if (mod->taints || |
4431 | mod->state == MODULE_STATE_GOING || | |
4432 | mod->state == MODULE_STATE_COMING) { | |
fa3ba2e8 | 4433 | buf[bx++] = '('; |
cca3e707 | 4434 | bx += module_flags_taint(mod, buf + bx); |
21aa9280 AV |
4435 | /* Show a - for module-is-being-unloaded */ |
4436 | if (mod->state == MODULE_STATE_GOING) | |
4437 | buf[bx++] = '-'; | |
4438 | /* Show a + for module-is-being-loaded */ | |
4439 | if (mod->state == MODULE_STATE_COMING) | |
4440 | buf[bx++] = '+'; | |
fa3ba2e8 FM |
4441 | buf[bx++] = ')'; |
4442 | } | |
4443 | buf[bx] = '\0'; | |
4444 | ||
4445 | return buf; | |
4446 | } | |
4447 | ||
3b5d5c6b AD |
4448 | #ifdef CONFIG_PROC_FS |
4449 | /* Called by the /proc file system to return a list of modules. */ | |
4450 | static void *m_start(struct seq_file *m, loff_t *pos) | |
4451 | { | |
4452 | mutex_lock(&module_mutex); | |
4453 | return seq_list_start(&modules, *pos); | |
4454 | } | |
4455 | ||
4456 | static void *m_next(struct seq_file *m, void *p, loff_t *pos) | |
4457 | { | |
4458 | return seq_list_next(p, &modules, pos); | |
4459 | } | |
4460 | ||
4461 | static void m_stop(struct seq_file *m, void *p) | |
4462 | { | |
4463 | mutex_unlock(&module_mutex); | |
4464 | } | |
4465 | ||
1da177e4 LT |
4466 | static int m_show(struct seq_file *m, void *p) |
4467 | { | |
4468 | struct module *mod = list_entry(p, struct module, list); | |
7fd8329b | 4469 | char buf[MODULE_FLAGS_BUF_SIZE]; |
668533dc | 4470 | void *value; |
fa3ba2e8 | 4471 | |
0d21b0e3 RR |
4472 | /* We always ignore unformed modules. */ |
4473 | if (mod->state == MODULE_STATE_UNFORMED) | |
4474 | return 0; | |
4475 | ||
2f0f2a33 | 4476 | seq_printf(m, "%s %u", |
7523e4dc | 4477 | mod->name, mod->init_layout.size + mod->core_layout.size); |
1da177e4 LT |
4478 | print_unload_info(m, mod); |
4479 | ||
4480 | /* Informative for users. */ | |
4481 | seq_printf(m, " %s", | |
6da0b565 IA |
4482 | mod->state == MODULE_STATE_GOING ? "Unloading" : |
4483 | mod->state == MODULE_STATE_COMING ? "Loading" : | |
1da177e4 LT |
4484 | "Live"); |
4485 | /* Used by oprofile and other similar tools. */ | |
668533dc LT |
4486 | value = m->private ? NULL : mod->core_layout.base; |
4487 | seq_printf(m, " 0x%px", value); | |
1da177e4 | 4488 | |
fa3ba2e8 FM |
4489 | /* Taints info */ |
4490 | if (mod->taints) | |
21aa9280 | 4491 | seq_printf(m, " %s", module_flags(mod, buf)); |
fa3ba2e8 | 4492 | |
6da0b565 | 4493 | seq_puts(m, "\n"); |
1da177e4 LT |
4494 | return 0; |
4495 | } | |
4496 | ||
4497 | /* Format: modulename size refcount deps address | |
4498 | ||
4499 | Where refcount is a number or -, and deps is a comma-separated list | |
4500 | of depends or -. | |
4501 | */ | |
3b5d5c6b | 4502 | static const struct seq_operations modules_op = { |
1da177e4 LT |
4503 | .start = m_start, |
4504 | .next = m_next, | |
4505 | .stop = m_stop, | |
4506 | .show = m_show | |
4507 | }; | |
4508 | ||
516fb7f2 LT |
4509 | /* |
4510 | * This also sets the "private" pointer to non-NULL if the | |
4511 | * kernel pointers should be hidden (so you can just test | |
4512 | * "m->private" to see if you should keep the values private). | |
4513 | * | |
4514 | * We use the same logic as for /proc/kallsyms. | |
4515 | */ | |
3b5d5c6b AD |
4516 | static int modules_open(struct inode *inode, struct file *file) |
4517 | { | |
516fb7f2 LT |
4518 | int err = seq_open(file, &modules_op); |
4519 | ||
4520 | if (!err) { | |
4521 | struct seq_file *m = file->private_data; | |
8f31494f | 4522 | m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul; |
516fb7f2 LT |
4523 | } |
4524 | ||
3f553b30 | 4525 | return err; |
3b5d5c6b AD |
4526 | } |
4527 | ||
4528 | static const struct file_operations proc_modules_operations = { | |
4529 | .open = modules_open, | |
4530 | .read = seq_read, | |
4531 | .llseek = seq_lseek, | |
4532 | .release = seq_release, | |
4533 | }; | |
4534 | ||
4535 | static int __init proc_modules_init(void) | |
4536 | { | |
4537 | proc_create("modules", 0, NULL, &proc_modules_operations); | |
4538 | return 0; | |
4539 | } | |
4540 | module_init(proc_modules_init); | |
4541 | #endif | |
4542 | ||
1da177e4 LT |
4543 | /* Given an address, look for it in the module exception tables. */ |
4544 | const struct exception_table_entry *search_module_extables(unsigned long addr) | |
4545 | { | |
1da177e4 LT |
4546 | const struct exception_table_entry *e = NULL; |
4547 | struct module *mod; | |
4548 | ||
24da1cbf | 4549 | preempt_disable(); |
5ff22646 PZ |
4550 | mod = __module_address(addr); |
4551 | if (!mod) | |
4552 | goto out; | |
22a8bdeb | 4553 | |
5ff22646 PZ |
4554 | if (!mod->num_exentries) |
4555 | goto out; | |
4556 | ||
4557 | e = search_extable(mod->extable, | |
a94c33dd | 4558 | mod->num_exentries, |
5ff22646 PZ |
4559 | addr); |
4560 | out: | |
24da1cbf | 4561 | preempt_enable(); |
1da177e4 | 4562 | |
5ff22646 PZ |
4563 | /* |
4564 | * Now, if we found one, we are running inside it now, hence | |
4565 | * we cannot unload the module, hence no refcnt needed. | |
4566 | */ | |
1da177e4 LT |
4567 | return e; |
4568 | } | |
4569 | ||
4d435f9d | 4570 | /* |
e610499e RR |
4571 | * is_module_address - is this address inside a module? |
4572 | * @addr: the address to check. | |
4573 | * | |
4574 | * See is_module_text_address() if you simply want to see if the address | |
4575 | * is code (not data). | |
4d435f9d | 4576 | */ |
e610499e | 4577 | bool is_module_address(unsigned long addr) |
4d435f9d | 4578 | { |
e610499e | 4579 | bool ret; |
4d435f9d | 4580 | |
24da1cbf | 4581 | preempt_disable(); |
e610499e | 4582 | ret = __module_address(addr) != NULL; |
24da1cbf | 4583 | preempt_enable(); |
4d435f9d | 4584 | |
e610499e | 4585 | return ret; |
4d435f9d IM |
4586 | } |
4587 | ||
e610499e RR |
4588 | /* |
4589 | * __module_address - get the module which contains an address. | |
4590 | * @addr: the address. | |
4591 | * | |
4592 | * Must be called with preempt disabled or module mutex held so that | |
4593 | * module doesn't get freed during this. | |
4594 | */ | |
714f83d5 | 4595 | struct module *__module_address(unsigned long addr) |
1da177e4 LT |
4596 | { |
4597 | struct module *mod; | |
4598 | ||
3a642e99 RR |
4599 | if (addr < module_addr_min || addr > module_addr_max) |
4600 | return NULL; | |
4601 | ||
0be964be PZ |
4602 | module_assert_mutex_or_preempt(); |
4603 | ||
6c9692e2 | 4604 | mod = mod_find(addr); |
93c2e105 PZ |
4605 | if (mod) { |
4606 | BUG_ON(!within_module(addr, mod)); | |
0d21b0e3 | 4607 | if (mod->state == MODULE_STATE_UNFORMED) |
93c2e105 | 4608 | mod = NULL; |
0d21b0e3 | 4609 | } |
93c2e105 | 4610 | return mod; |
1da177e4 | 4611 | } |
fbf63ce3 | 4612 | EXPORT_SYMBOL_GPL(__module_address); |
1da177e4 | 4613 | |
e610499e RR |
4614 | /* |
4615 | * is_module_text_address - is this address inside module code? | |
4616 | * @addr: the address to check. | |
4617 | * | |
4618 | * See is_module_address() if you simply want to see if the address is | |
4619 | * anywhere in a module. See kernel_text_address() for testing if an | |
4620 | * address corresponds to kernel or module code. | |
4621 | */ | |
4622 | bool is_module_text_address(unsigned long addr) | |
4623 | { | |
4624 | bool ret; | |
4625 | ||
4626 | preempt_disable(); | |
4627 | ret = __module_text_address(addr) != NULL; | |
4628 | preempt_enable(); | |
4629 | ||
4630 | return ret; | |
4631 | } | |
4632 | ||
4633 | /* | |
4634 | * __module_text_address - get the module whose code contains an address. | |
4635 | * @addr: the address. | |
4636 | * | |
4637 | * Must be called with preempt disabled or module mutex held so that | |
4638 | * module doesn't get freed during this. | |
4639 | */ | |
4640 | struct module *__module_text_address(unsigned long addr) | |
4641 | { | |
4642 | struct module *mod = __module_address(addr); | |
4643 | if (mod) { | |
4644 | /* Make sure it's within the text section. */ | |
7523e4dc RR |
4645 | if (!within(addr, mod->init_layout.base, mod->init_layout.text_size) |
4646 | && !within(addr, mod->core_layout.base, mod->core_layout.text_size)) | |
e610499e RR |
4647 | mod = NULL; |
4648 | } | |
4649 | return mod; | |
4650 | } | |
23c0cf8a | 4651 | EXPORT_SYMBOL_GPL(__module_text_address); |
e610499e | 4652 | |
1da177e4 LT |
4653 | /* Don't grab lock, we're oopsing. */ |
4654 | void print_modules(void) | |
4655 | { | |
4656 | struct module *mod; | |
7fd8329b | 4657 | char buf[MODULE_FLAGS_BUF_SIZE]; |
1da177e4 | 4658 | |
b231125a | 4659 | printk(KERN_DEFAULT "Modules linked in:"); |
d72b3751 AK |
4660 | /* Most callers should already have preempt disabled, but make sure */ |
4661 | preempt_disable(); | |
0d21b0e3 RR |
4662 | list_for_each_entry_rcu(mod, &modules, list) { |
4663 | if (mod->state == MODULE_STATE_UNFORMED) | |
4664 | continue; | |
27bba4d6 | 4665 | pr_cont(" %s%s", mod->name, module_flags(mod, buf)); |
0d21b0e3 | 4666 | } |
d72b3751 | 4667 | preempt_enable(); |
e14af7ee | 4668 | if (last_unloaded_module[0]) |
27bba4d6 JS |
4669 | pr_cont(" [last unloaded: %s]", last_unloaded_module); |
4670 | pr_cont("\n"); | |
1da177e4 LT |
4671 | } |
4672 | ||
1da177e4 | 4673 | #ifdef CONFIG_MODVERSIONS |
8c8ef42a RR |
4674 | /* Generate the signature for all relevant module structures here. |
4675 | * If these change, we don't want to try to parse the module. */ | |
4676 | void module_layout(struct module *mod, | |
4677 | struct modversion_info *ver, | |
4678 | struct kernel_param *kp, | |
4679 | struct kernel_symbol *ks, | |
65498646 | 4680 | struct tracepoint * const *tp) |
8c8ef42a RR |
4681 | { |
4682 | } | |
4683 | EXPORT_SYMBOL(module_layout); | |
1da177e4 | 4684 | #endif |