]>
Commit | Line | Data |
---|---|---|
1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
f71d20e9 | 2 | /* |
24b9f0d2 SS |
3 | * Copyright (C) 2002 Richard Henderson |
4 | * Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM. | |
5 | */ | |
51161bfc LR |
6 | |
7 | #define INCLUDE_VERMAGIC | |
8 | ||
9984de1a | 9 | #include <linux/export.h> |
8a293be0 | 10 | #include <linux/extable.h> |
1da177e4 | 11 | #include <linux/moduleloader.h> |
c8424e77 | 12 | #include <linux/module_signature.h> |
af658dca | 13 | #include <linux/trace_events.h> |
1da177e4 | 14 | #include <linux/init.h> |
ae84e324 | 15 | #include <linux/kallsyms.h> |
9294523e | 16 | #include <linux/buildid.h> |
34e1169d | 17 | #include <linux/file.h> |
3b5d5c6b | 18 | #include <linux/fs.h> |
6d760133 | 19 | #include <linux/sysfs.h> |
9f158333 | 20 | #include <linux/kernel.h> |
b89999d0 | 21 | #include <linux/kernel_read_file.h> |
1da177e4 LT |
22 | #include <linux/slab.h> |
23 | #include <linux/vmalloc.h> | |
24 | #include <linux/elf.h> | |
3b5d5c6b | 25 | #include <linux/proc_fs.h> |
2e72d51b | 26 | #include <linux/security.h> |
1da177e4 LT |
27 | #include <linux/seq_file.h> |
28 | #include <linux/syscalls.h> | |
29 | #include <linux/fcntl.h> | |
30 | #include <linux/rcupdate.h> | |
c59ede7b | 31 | #include <linux/capability.h> |
1da177e4 LT |
32 | #include <linux/cpu.h> |
33 | #include <linux/moduleparam.h> | |
34 | #include <linux/errno.h> | |
35 | #include <linux/err.h> | |
36 | #include <linux/vermagic.h> | |
37 | #include <linux/notifier.h> | |
f6a57033 | 38 | #include <linux/sched.h> |
1da177e4 | 39 | #include <linux/device.h> |
c988d2b2 | 40 | #include <linux/string.h> |
97d1f15b | 41 | #include <linux/mutex.h> |
d72b3751 | 42 | #include <linux/rculist.h> |
7c0f6ba6 | 43 | #include <linux/uaccess.h> |
1da177e4 | 44 | #include <asm/cacheflush.h> |
563ec5cb | 45 | #include <linux/set_memory.h> |
eb8cdec4 | 46 | #include <asm/mmu_context.h> |
b817f6fe | 47 | #include <linux/license.h> |
6d762394 | 48 | #include <asm/sections.h> |
97e1c18e | 49 | #include <linux/tracepoint.h> |
90d595fe | 50 | #include <linux/ftrace.h> |
7e545d6e | 51 | #include <linux/livepatch.h> |
22a9d645 | 52 | #include <linux/async.h> |
fbf59bc9 | 53 | #include <linux/percpu.h> |
4f2294b6 | 54 | #include <linux/kmemleak.h> |
bf5438fc | 55 | #include <linux/jump_label.h> |
84e1c6bb | 56 | #include <linux/pfn.h> |
403ed278 | 57 | #include <linux/bsearch.h> |
9d5059c9 | 58 | #include <linux/dynamic_debug.h> |
ca86cad7 | 59 | #include <linux/audit.h> |
2f3238ae | 60 | #include <uapi/linux/module.h> |
106a4ee2 | 61 | #include "module-internal.h" |
1da177e4 | 62 | |
7ead8b83 LZ |
63 | #define CREATE_TRACE_POINTS |
64 | #include <trace/events/module.h> | |
65 | ||
1da177e4 LT |
66 | #ifndef ARCH_SHF_SMALL |
67 | #define ARCH_SHF_SMALL 0 | |
68 | #endif | |
69 | ||
84e1c6bb MC |
70 | /* |
71 | * Modules' sections will be aligned on page boundaries | |
3b5be16c HZ |
72 | * to ensure complete separation of code and data, but |
73 | * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y | |
84e1c6bb | 74 | */ |
3b5be16c | 75 | #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX |
84e1c6bb | 76 | # define debug_align(X) ALIGN(X, PAGE_SIZE) |
3b5be16c HZ |
77 | #else |
78 | # define debug_align(X) (X) | |
79 | #endif | |
84e1c6bb | 80 | |
1da177e4 LT |
81 | /* If this is set, the section belongs in the init part of the module */ |
82 | #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) | |
83 | ||
75676500 RR |
84 | /* |
85 | * Mutex protects: | |
86 | * 1) List of modules (also safely readable with preempt_disable), | |
87 | * 2) module_use links, | |
88 | * 3) module_addr_min/module_addr_max. | |
24b9f0d2 SS |
89 | * (delete and add uses RCU list operations). |
90 | */ | |
922f2a7c | 91 | static DEFINE_MUTEX(module_mutex); |
1da177e4 | 92 | static LIST_HEAD(modules); |
67fc4e0c | 93 | |
1a7b7d92 | 94 | /* Work queue for freeing init sections in success case */ |
fdf09ab8 DJ |
95 | static void do_free_init(struct work_struct *w); |
96 | static DECLARE_WORK(init_free_wq, do_free_init); | |
97 | static LLIST_HEAD(init_free_list); | |
1a7b7d92 | 98 | |
6c9692e2 | 99 | #ifdef CONFIG_MODULES_TREE_LOOKUP |
106a4ee2 | 100 | |
93c2e105 PZ |
101 | /* |
102 | * Use a latched RB-tree for __module_address(); this allows us to use | |
103 | * RCU-sched lookups of the address from any context. | |
104 | * | |
6c9692e2 PZ |
105 | * This is conditional on PERF_EVENTS || TRACING because those can really hit |
106 | * __module_address() hard by doing a lot of stack unwinding; potentially from | |
107 | * NMI context. | |
93c2e105 PZ |
108 | */ |
109 | ||
110 | static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n) | |
106a4ee2 | 111 | { |
7523e4dc | 112 | struct module_layout *layout = container_of(n, struct module_layout, mtn.node); |
106a4ee2 | 113 | |
7523e4dc | 114 | return (unsigned long)layout->base; |
93c2e105 PZ |
115 | } |
116 | ||
117 | static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n) | |
118 | { | |
7523e4dc | 119 | struct module_layout *layout = container_of(n, struct module_layout, mtn.node); |
93c2e105 | 120 | |
7523e4dc | 121 | return (unsigned long)layout->size; |
93c2e105 PZ |
122 | } |
123 | ||
124 | static __always_inline bool | |
125 | mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b) | |
126 | { | |
127 | return __mod_tree_val(a) < __mod_tree_val(b); | |
128 | } | |
129 | ||
130 | static __always_inline int | |
131 | mod_tree_comp(void *key, struct latch_tree_node *n) | |
132 | { | |
133 | unsigned long val = (unsigned long)key; | |
134 | unsigned long start, end; | |
135 | ||
136 | start = __mod_tree_val(n); | |
137 | if (val < start) | |
138 | return -1; | |
139 | ||
140 | end = start + __mod_tree_size(n); | |
141 | if (val >= end) | |
142 | return 1; | |
106a4ee2 | 143 | |
106a4ee2 RR |
144 | return 0; |
145 | } | |
146 | ||
93c2e105 PZ |
147 | static const struct latch_tree_ops mod_tree_ops = { |
148 | .less = mod_tree_less, | |
149 | .comp = mod_tree_comp, | |
150 | }; | |
151 | ||
4f666546 PZ |
152 | static struct mod_tree_root { |
153 | struct latch_tree_root root; | |
154 | unsigned long addr_min; | |
155 | unsigned long addr_max; | |
156 | } mod_tree __cacheline_aligned = { | |
157 | .addr_min = -1UL, | |
106a4ee2 | 158 | }; |
106a4ee2 | 159 | |
4f666546 PZ |
160 | #define module_addr_min mod_tree.addr_min |
161 | #define module_addr_max mod_tree.addr_max | |
162 | ||
163 | static noinline void __mod_tree_insert(struct mod_tree_node *node) | |
164 | { | |
165 | latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops); | |
166 | } | |
167 | ||
168 | static void __mod_tree_remove(struct mod_tree_node *node) | |
169 | { | |
170 | latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops); | |
171 | } | |
93c2e105 PZ |
172 | |
173 | /* | |
174 | * These modifications: insert, remove_init and remove; are serialized by the | |
175 | * module_mutex. | |
176 | */ | |
177 | static void mod_tree_insert(struct module *mod) | |
178 | { | |
7523e4dc RR |
179 | mod->core_layout.mtn.mod = mod; |
180 | mod->init_layout.mtn.mod = mod; | |
93c2e105 | 181 | |
7523e4dc RR |
182 | __mod_tree_insert(&mod->core_layout.mtn); |
183 | if (mod->init_layout.size) | |
184 | __mod_tree_insert(&mod->init_layout.mtn); | |
93c2e105 PZ |
185 | } |
186 | ||
187 | static void mod_tree_remove_init(struct module *mod) | |
188 | { | |
7523e4dc RR |
189 | if (mod->init_layout.size) |
190 | __mod_tree_remove(&mod->init_layout.mtn); | |
93c2e105 PZ |
191 | } |
192 | ||
193 | static void mod_tree_remove(struct module *mod) | |
194 | { | |
7523e4dc | 195 | __mod_tree_remove(&mod->core_layout.mtn); |
93c2e105 PZ |
196 | mod_tree_remove_init(mod); |
197 | } | |
198 | ||
6c9692e2 | 199 | static struct module *mod_find(unsigned long addr) |
93c2e105 PZ |
200 | { |
201 | struct latch_tree_node *ltn; | |
202 | ||
4f666546 | 203 | ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops); |
93c2e105 PZ |
204 | if (!ltn) |
205 | return NULL; | |
206 | ||
207 | return container_of(ltn, struct mod_tree_node, node)->mod; | |
208 | } | |
209 | ||
6c9692e2 PZ |
210 | #else /* MODULES_TREE_LOOKUP */ |
211 | ||
4f666546 PZ |
212 | static unsigned long module_addr_min = -1UL, module_addr_max = 0; |
213 | ||
6c9692e2 PZ |
214 | static void mod_tree_insert(struct module *mod) { } |
215 | static void mod_tree_remove_init(struct module *mod) { } | |
216 | static void mod_tree_remove(struct module *mod) { } | |
217 | ||
218 | static struct module *mod_find(unsigned long addr) | |
219 | { | |
220 | struct module *mod; | |
221 | ||
bf08949c MH |
222 | list_for_each_entry_rcu(mod, &modules, list, |
223 | lockdep_is_held(&module_mutex)) { | |
6c9692e2 PZ |
224 | if (within_module(addr, mod)) |
225 | return mod; | |
226 | } | |
227 | ||
228 | return NULL; | |
229 | } | |
230 | ||
231 | #endif /* MODULES_TREE_LOOKUP */ | |
232 | ||
4f666546 PZ |
233 | /* |
234 | * Bounds of module text, for speeding up __module_address. | |
235 | * Protected by module_mutex. | |
236 | */ | |
237 | static void __mod_update_bounds(void *base, unsigned int size) | |
238 | { | |
239 | unsigned long min = (unsigned long)base; | |
240 | unsigned long max = min + size; | |
241 | ||
242 | if (min < module_addr_min) | |
243 | module_addr_min = min; | |
244 | if (max > module_addr_max) | |
245 | module_addr_max = max; | |
246 | } | |
247 | ||
248 | static void mod_update_bounds(struct module *mod) | |
249 | { | |
7523e4dc RR |
250 | __mod_update_bounds(mod->core_layout.base, mod->core_layout.size); |
251 | if (mod->init_layout.size) | |
252 | __mod_update_bounds(mod->init_layout.base, mod->init_layout.size); | |
4f666546 PZ |
253 | } |
254 | ||
67fc4e0c JW |
255 | #ifdef CONFIG_KGDB_KDB |
256 | struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ | |
257 | #endif /* CONFIG_KGDB_KDB */ | |
258 | ||
0be964be PZ |
259 | static void module_assert_mutex_or_preempt(void) |
260 | { | |
261 | #ifdef CONFIG_LOCKDEP | |
262 | if (unlikely(!debug_locks)) | |
263 | return; | |
264 | ||
9502514f | 265 | WARN_ON_ONCE(!rcu_read_lock_sched_held() && |
0be964be PZ |
266 | !lockdep_is_held(&module_mutex)); |
267 | #endif | |
268 | } | |
269 | ||
0c18f29a | 270 | #ifdef CONFIG_MODULE_SIG |
6727bb9c | 271 | static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE); |
106a4ee2 | 272 | module_param(sig_enforce, bool_enable_only, 0644); |
1da177e4 | 273 | |
0c18f29a MZ |
274 | void set_module_sig_enforced(void) |
275 | { | |
276 | sig_enforce = true; | |
277 | } | |
278 | #else | |
279 | #define sig_enforce false | |
280 | #endif | |
281 | ||
fda784e5 BM |
282 | /* |
283 | * Export sig_enforce kernel cmdline parameter to allow other subsystems rely | |
284 | * on that instead of directly to CONFIG_MODULE_SIG_FORCE config. | |
285 | */ | |
286 | bool is_module_sig_enforced(void) | |
287 | { | |
288 | return sig_enforce; | |
289 | } | |
290 | EXPORT_SYMBOL(is_module_sig_enforced); | |
291 | ||
19e4529e SR |
292 | /* Block module loading/unloading? */ |
293 | int modules_disabled = 0; | |
02608bef | 294 | core_param(nomodule, modules_disabled, bint, 0); |
19e4529e | 295 | |
c9a3ba55 RR |
296 | /* Waiting for a module to finish initializing? */ |
297 | static DECLARE_WAIT_QUEUE_HEAD(module_wq); | |
298 | ||
e041c683 | 299 | static BLOCKING_NOTIFIER_HEAD(module_notify_list); |
1da177e4 | 300 | |
6da0b565 | 301 | int register_module_notifier(struct notifier_block *nb) |
1da177e4 | 302 | { |
e041c683 | 303 | return blocking_notifier_chain_register(&module_notify_list, nb); |
1da177e4 LT |
304 | } |
305 | EXPORT_SYMBOL(register_module_notifier); | |
306 | ||
6da0b565 | 307 | int unregister_module_notifier(struct notifier_block *nb) |
1da177e4 | 308 | { |
e041c683 | 309 | return blocking_notifier_chain_unregister(&module_notify_list, nb); |
1da177e4 LT |
310 | } |
311 | EXPORT_SYMBOL(unregister_module_notifier); | |
312 | ||
71d9f507 MB |
313 | /* |
314 | * We require a truly strong try_module_get(): 0 means success. | |
315 | * Otherwise an error is returned due to ongoing or failed | |
316 | * initialization etc. | |
317 | */ | |
1da177e4 LT |
318 | static inline int strong_try_module_get(struct module *mod) |
319 | { | |
0d21b0e3 | 320 | BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED); |
1da177e4 | 321 | if (mod && mod->state == MODULE_STATE_COMING) |
c9a3ba55 RR |
322 | return -EBUSY; |
323 | if (try_module_get(mod)) | |
1da177e4 | 324 | return 0; |
c9a3ba55 RR |
325 | else |
326 | return -ENOENT; | |
1da177e4 LT |
327 | } |
328 | ||
373d4d09 RR |
329 | static inline void add_taint_module(struct module *mod, unsigned flag, |
330 | enum lockdep_ok lockdep_ok) | |
fa3ba2e8 | 331 | { |
373d4d09 | 332 | add_taint(flag, lockdep_ok); |
7fd8329b | 333 | set_bit(flag, &mod->taints); |
fa3ba2e8 FM |
334 | } |
335 | ||
02a3e59a RD |
336 | /* |
337 | * A thread that wants to hold a reference to a module only while it | |
338 | * is running can call this to safely exit. nfsd and lockd use this. | |
1da177e4 | 339 | */ |
bf262dce | 340 | void __noreturn __module_put_and_exit(struct module *mod, long code) |
1da177e4 LT |
341 | { |
342 | module_put(mod); | |
343 | do_exit(code); | |
344 | } | |
345 | EXPORT_SYMBOL(__module_put_and_exit); | |
22a8bdeb | 346 | |
1da177e4 | 347 | /* Find a module section: 0 means not found. */ |
49668688 | 348 | static unsigned int find_sec(const struct load_info *info, const char *name) |
1da177e4 LT |
349 | { |
350 | unsigned int i; | |
351 | ||
49668688 RR |
352 | for (i = 1; i < info->hdr->e_shnum; i++) { |
353 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
1da177e4 | 354 | /* Alloc bit cleared means "ignore it." */ |
49668688 RR |
355 | if ((shdr->sh_flags & SHF_ALLOC) |
356 | && strcmp(info->secstrings + shdr->sh_name, name) == 0) | |
1da177e4 | 357 | return i; |
49668688 | 358 | } |
1da177e4 LT |
359 | return 0; |
360 | } | |
361 | ||
5e458cc0 | 362 | /* Find a module section, or NULL. */ |
49668688 | 363 | static void *section_addr(const struct load_info *info, const char *name) |
5e458cc0 RR |
364 | { |
365 | /* Section 0 has sh_addr 0. */ | |
49668688 | 366 | return (void *)info->sechdrs[find_sec(info, name)].sh_addr; |
5e458cc0 RR |
367 | } |
368 | ||
369 | /* Find a module section, or NULL. Fill in number of "objects" in section. */ | |
49668688 | 370 | static void *section_objs(const struct load_info *info, |
5e458cc0 RR |
371 | const char *name, |
372 | size_t object_size, | |
373 | unsigned int *num) | |
374 | { | |
49668688 | 375 | unsigned int sec = find_sec(info, name); |
5e458cc0 RR |
376 | |
377 | /* Section 0 has sh_addr 0 and sh_size 0. */ | |
49668688 RR |
378 | *num = info->sechdrs[sec].sh_size / object_size; |
379 | return (void *)info->sechdrs[sec].sh_addr; | |
5e458cc0 RR |
380 | } |
381 | ||
36e68442 AN |
382 | /* Find a module section: 0 means not found. Ignores SHF_ALLOC flag. */ |
383 | static unsigned int find_any_sec(const struct load_info *info, const char *name) | |
384 | { | |
385 | unsigned int i; | |
386 | ||
387 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
388 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
389 | if (strcmp(info->secstrings + shdr->sh_name, name) == 0) | |
390 | return i; | |
391 | } | |
392 | return 0; | |
393 | } | |
394 | ||
395 | /* | |
396 | * Find a module section, or NULL. Fill in number of "objects" in section. | |
397 | * Ignores SHF_ALLOC flag. | |
398 | */ | |
399 | static __maybe_unused void *any_section_objs(const struct load_info *info, | |
400 | const char *name, | |
401 | size_t object_size, | |
402 | unsigned int *num) | |
403 | { | |
404 | unsigned int sec = find_any_sec(info, name); | |
405 | ||
406 | /* Section 0 has sh_addr 0 and sh_size 0. */ | |
407 | *num = info->sechdrs[sec].sh_size / object_size; | |
408 | return (void *)info->sechdrs[sec].sh_addr; | |
409 | } | |
410 | ||
1da177e4 LT |
411 | /* Provided by the linker */ |
412 | extern const struct kernel_symbol __start___ksymtab[]; | |
413 | extern const struct kernel_symbol __stop___ksymtab[]; | |
414 | extern const struct kernel_symbol __start___ksymtab_gpl[]; | |
415 | extern const struct kernel_symbol __stop___ksymtab_gpl[]; | |
71810db2 AB |
416 | extern const s32 __start___kcrctab[]; |
417 | extern const s32 __start___kcrctab_gpl[]; | |
1da177e4 LT |
418 | |
419 | #ifndef CONFIG_MODVERSIONS | |
420 | #define symversion(base, idx) NULL | |
421 | #else | |
f83ca9fe | 422 | #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL) |
1da177e4 LT |
423 | #endif |
424 | ||
00cc2c1c CH |
425 | struct symsearch { |
426 | const struct kernel_symbol *start, *stop; | |
427 | const s32 *crcs; | |
428 | enum mod_license { | |
429 | NOT_GPL_ONLY, | |
430 | GPL_ONLY, | |
00cc2c1c | 431 | } license; |
00cc2c1c CH |
432 | }; |
433 | ||
dafd0940 RR |
434 | struct find_symbol_arg { |
435 | /* Input */ | |
436 | const char *name; | |
437 | bool gplok; | |
438 | bool warn; | |
439 | ||
440 | /* Output */ | |
441 | struct module *owner; | |
71810db2 | 442 | const s32 *crc; |
414fd31b | 443 | const struct kernel_symbol *sym; |
ef1dac60 | 444 | enum mod_license license; |
dafd0940 RR |
445 | }; |
446 | ||
2d25bc55 JY |
447 | static bool check_exported_symbol(const struct symsearch *syms, |
448 | struct module *owner, | |
449 | unsigned int symnum, void *data) | |
dafd0940 RR |
450 | { |
451 | struct find_symbol_arg *fsa = data; | |
452 | ||
f1c3d73e CH |
453 | if (!fsa->gplok && syms->license == GPL_ONLY) |
454 | return false; | |
dafd0940 RR |
455 | fsa->owner = owner; |
456 | fsa->crc = symversion(syms->crcs, symnum); | |
414fd31b | 457 | fsa->sym = &syms->start[symnum]; |
ef1dac60 | 458 | fsa->license = syms->license; |
dafd0940 RR |
459 | return true; |
460 | } | |
461 | ||
7290d580 AB |
462 | static unsigned long kernel_symbol_value(const struct kernel_symbol *sym) |
463 | { | |
464 | #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS | |
465 | return (unsigned long)offset_to_ptr(&sym->value_offset); | |
466 | #else | |
467 | return sym->value; | |
468 | #endif | |
469 | } | |
470 | ||
471 | static const char *kernel_symbol_name(const struct kernel_symbol *sym) | |
472 | { | |
473 | #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS | |
474 | return offset_to_ptr(&sym->name_offset); | |
475 | #else | |
476 | return sym->name; | |
477 | #endif | |
478 | } | |
479 | ||
8651ec01 MM |
480 | static const char *kernel_symbol_namespace(const struct kernel_symbol *sym) |
481 | { | |
482 | #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS | |
069e1c07 WD |
483 | if (!sym->namespace_offset) |
484 | return NULL; | |
8651ec01 MM |
485 | return offset_to_ptr(&sym->namespace_offset); |
486 | #else | |
487 | return sym->namespace; | |
488 | #endif | |
489 | } | |
490 | ||
b605be65 | 491 | static int cmp_name(const void *name, const void *sym) |
403ed278 | 492 | { |
b605be65 | 493 | return strcmp(name, kernel_symbol_name(sym)); |
403ed278 AIB |
494 | } |
495 | ||
2d25bc55 JY |
496 | static bool find_exported_symbol_in_section(const struct symsearch *syms, |
497 | struct module *owner, | |
498 | void *data) | |
de4d8d53 RR |
499 | { |
500 | struct find_symbol_arg *fsa = data; | |
403ed278 AIB |
501 | struct kernel_symbol *sym; |
502 | ||
503 | sym = bsearch(fsa->name, syms->start, syms->stop - syms->start, | |
504 | sizeof(struct kernel_symbol), cmp_name); | |
505 | ||
2d25bc55 JY |
506 | if (sym != NULL && check_exported_symbol(syms, owner, |
507 | sym - syms->start, data)) | |
403ed278 | 508 | return true; |
de4d8d53 | 509 | |
de4d8d53 RR |
510 | return false; |
511 | } | |
512 | ||
24b9f0d2 SS |
513 | /* |
514 | * Find an exported symbol and return it, along with, (optional) crc and | |
515 | * (optional) module which owns it. Needs preempt disabled or module_mutex. | |
516 | */ | |
0b96615c | 517 | static bool find_symbol(struct find_symbol_arg *fsa) |
dafd0940 | 518 | { |
71e4b309 CH |
519 | static const struct symsearch arr[] = { |
520 | { __start___ksymtab, __stop___ksymtab, __start___kcrctab, | |
36794822 | 521 | NOT_GPL_ONLY }, |
71e4b309 CH |
522 | { __start___ksymtab_gpl, __stop___ksymtab_gpl, |
523 | __start___kcrctab_gpl, | |
36794822 | 524 | GPL_ONLY }, |
71e4b309 | 525 | }; |
71e4b309 CH |
526 | struct module *mod; |
527 | unsigned int i; | |
dafd0940 | 528 | |
71e4b309 | 529 | module_assert_mutex_or_preempt(); |
dafd0940 | 530 | |
71e4b309 | 531 | for (i = 0; i < ARRAY_SIZE(arr); i++) |
0b96615c CH |
532 | if (find_exported_symbol_in_section(&arr[i], NULL, fsa)) |
533 | return true; | |
71e4b309 CH |
534 | |
535 | list_for_each_entry_rcu(mod, &modules, list, | |
536 | lockdep_is_held(&module_mutex)) { | |
537 | struct symsearch arr[] = { | |
538 | { mod->syms, mod->syms + mod->num_syms, mod->crcs, | |
36794822 | 539 | NOT_GPL_ONLY }, |
71e4b309 CH |
540 | { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, |
541 | mod->gpl_crcs, | |
36794822 | 542 | GPL_ONLY }, |
71e4b309 CH |
543 | }; |
544 | ||
545 | if (mod->state == MODULE_STATE_UNFORMED) | |
546 | continue; | |
547 | ||
548 | for (i = 0; i < ARRAY_SIZE(arr); i++) | |
0b96615c CH |
549 | if (find_exported_symbol_in_section(&arr[i], mod, fsa)) |
550 | return true; | |
dafd0940 RR |
551 | } |
552 | ||
0b96615c CH |
553 | pr_debug("Failed to find symbol %s\n", fsa->name); |
554 | return false; | |
1da177e4 LT |
555 | } |
556 | ||
fe0d34d2 RR |
557 | /* |
558 | * Search for module by name: must hold module_mutex (or preempt disabled | |
559 | * for read-only access). | |
560 | */ | |
4f6de4d5 | 561 | static struct module *find_module_all(const char *name, size_t len, |
0d21b0e3 | 562 | bool even_unformed) |
1da177e4 LT |
563 | { |
564 | struct module *mod; | |
565 | ||
fe0d34d2 | 566 | module_assert_mutex_or_preempt(); |
0be964be | 567 | |
bf08949c MH |
568 | list_for_each_entry_rcu(mod, &modules, list, |
569 | lockdep_is_held(&module_mutex)) { | |
0d21b0e3 RR |
570 | if (!even_unformed && mod->state == MODULE_STATE_UNFORMED) |
571 | continue; | |
4f6de4d5 | 572 | if (strlen(mod->name) == len && !memcmp(mod->name, name, len)) |
1da177e4 LT |
573 | return mod; |
574 | } | |
575 | return NULL; | |
576 | } | |
0d21b0e3 RR |
577 | |
578 | struct module *find_module(const char *name) | |
579 | { | |
4f6de4d5 | 580 | return find_module_all(name, strlen(name), false); |
0d21b0e3 | 581 | } |
1da177e4 LT |
582 | |
583 | #ifdef CONFIG_SMP | |
fbf59bc9 | 584 | |
259354de | 585 | static inline void __percpu *mod_percpu(struct module *mod) |
fbf59bc9 | 586 | { |
259354de TH |
587 | return mod->percpu; |
588 | } | |
fbf59bc9 | 589 | |
9eb76d77 | 590 | static int percpu_modalloc(struct module *mod, struct load_info *info) |
259354de | 591 | { |
9eb76d77 RR |
592 | Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu]; |
593 | unsigned long align = pcpusec->sh_addralign; | |
594 | ||
595 | if (!pcpusec->sh_size) | |
596 | return 0; | |
597 | ||
fbf59bc9 | 598 | if (align > PAGE_SIZE) { |
bddb12b3 AM |
599 | pr_warn("%s: per-cpu alignment %li > %li\n", |
600 | mod->name, align, PAGE_SIZE); | |
fbf59bc9 TH |
601 | align = PAGE_SIZE; |
602 | } | |
603 | ||
9eb76d77 | 604 | mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align); |
259354de | 605 | if (!mod->percpu) { |
bddb12b3 AM |
606 | pr_warn("%s: Could not allocate %lu bytes percpu data\n", |
607 | mod->name, (unsigned long)pcpusec->sh_size); | |
259354de TH |
608 | return -ENOMEM; |
609 | } | |
9eb76d77 | 610 | mod->percpu_size = pcpusec->sh_size; |
259354de | 611 | return 0; |
fbf59bc9 TH |
612 | } |
613 | ||
259354de | 614 | static void percpu_modfree(struct module *mod) |
fbf59bc9 | 615 | { |
259354de | 616 | free_percpu(mod->percpu); |
fbf59bc9 TH |
617 | } |
618 | ||
49668688 | 619 | static unsigned int find_pcpusec(struct load_info *info) |
6b588c18 | 620 | { |
49668688 | 621 | return find_sec(info, ".data..percpu"); |
6b588c18 TH |
622 | } |
623 | ||
259354de TH |
624 | static void percpu_modcopy(struct module *mod, |
625 | const void *from, unsigned long size) | |
6b588c18 TH |
626 | { |
627 | int cpu; | |
628 | ||
629 | for_each_possible_cpu(cpu) | |
259354de | 630 | memcpy(per_cpu_ptr(mod->percpu, cpu), from, size); |
6b588c18 TH |
631 | } |
632 | ||
383776fa | 633 | bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr) |
10fad5e4 TH |
634 | { |
635 | struct module *mod; | |
636 | unsigned int cpu; | |
637 | ||
638 | preempt_disable(); | |
639 | ||
640 | list_for_each_entry_rcu(mod, &modules, list) { | |
0d21b0e3 RR |
641 | if (mod->state == MODULE_STATE_UNFORMED) |
642 | continue; | |
10fad5e4 TH |
643 | if (!mod->percpu_size) |
644 | continue; | |
645 | for_each_possible_cpu(cpu) { | |
646 | void *start = per_cpu_ptr(mod->percpu, cpu); | |
383776fa | 647 | void *va = (void *)addr; |
10fad5e4 | 648 | |
383776fa | 649 | if (va >= start && va < start + mod->percpu_size) { |
8ce371f9 | 650 | if (can_addr) { |
383776fa | 651 | *can_addr = (unsigned long) (va - start); |
8ce371f9 PZ |
652 | *can_addr += (unsigned long) |
653 | per_cpu_ptr(mod->percpu, | |
654 | get_boot_cpu_id()); | |
655 | } | |
10fad5e4 TH |
656 | preempt_enable(); |
657 | return true; | |
658 | } | |
659 | } | |
660 | } | |
661 | ||
662 | preempt_enable(); | |
663 | return false; | |
6b588c18 TH |
664 | } |
665 | ||
383776fa | 666 | /** |
24389b61 | 667 | * is_module_percpu_address() - test whether address is from module static percpu |
383776fa TG |
668 | * @addr: address to test |
669 | * | |
670 | * Test whether @addr belongs to module static percpu area. | |
671 | * | |
24389b61 | 672 | * Return: %true if @addr is from module static percpu area |
383776fa TG |
673 | */ |
674 | bool is_module_percpu_address(unsigned long addr) | |
675 | { | |
676 | return __is_module_percpu_address(addr, NULL); | |
677 | } | |
678 | ||
1da177e4 | 679 | #else /* ... !CONFIG_SMP */ |
6b588c18 | 680 | |
259354de | 681 | static inline void __percpu *mod_percpu(struct module *mod) |
1da177e4 LT |
682 | { |
683 | return NULL; | |
684 | } | |
9eb76d77 | 685 | static int percpu_modalloc(struct module *mod, struct load_info *info) |
259354de | 686 | { |
9eb76d77 RR |
687 | /* UP modules shouldn't have this section: ENOMEM isn't quite right */ |
688 | if (info->sechdrs[info->index.pcpu].sh_size != 0) | |
689 | return -ENOMEM; | |
690 | return 0; | |
259354de TH |
691 | } |
692 | static inline void percpu_modfree(struct module *mod) | |
1da177e4 | 693 | { |
1da177e4 | 694 | } |
49668688 | 695 | static unsigned int find_pcpusec(struct load_info *info) |
1da177e4 LT |
696 | { |
697 | return 0; | |
698 | } | |
259354de TH |
699 | static inline void percpu_modcopy(struct module *mod, |
700 | const void *from, unsigned long size) | |
1da177e4 LT |
701 | { |
702 | /* pcpusec should be 0, and size of that section should be 0. */ | |
703 | BUG_ON(size != 0); | |
704 | } | |
10fad5e4 TH |
705 | bool is_module_percpu_address(unsigned long addr) |
706 | { | |
707 | return false; | |
708 | } | |
6b588c18 | 709 | |
383776fa TG |
710 | bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr) |
711 | { | |
712 | return false; | |
713 | } | |
714 | ||
1da177e4 LT |
715 | #endif /* CONFIG_SMP */ |
716 | ||
c988d2b2 MD |
717 | #define MODINFO_ATTR(field) \ |
718 | static void setup_modinfo_##field(struct module *mod, const char *s) \ | |
719 | { \ | |
720 | mod->field = kstrdup(s, GFP_KERNEL); \ | |
721 | } \ | |
722 | static ssize_t show_modinfo_##field(struct module_attribute *mattr, \ | |
4befb026 | 723 | struct module_kobject *mk, char *buffer) \ |
c988d2b2 | 724 | { \ |
cc56ded3 | 725 | return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \ |
c988d2b2 MD |
726 | } \ |
727 | static int modinfo_##field##_exists(struct module *mod) \ | |
728 | { \ | |
729 | return mod->field != NULL; \ | |
730 | } \ | |
731 | static void free_modinfo_##field(struct module *mod) \ | |
732 | { \ | |
22a8bdeb DW |
733 | kfree(mod->field); \ |
734 | mod->field = NULL; \ | |
c988d2b2 MD |
735 | } \ |
736 | static struct module_attribute modinfo_##field = { \ | |
7b595756 | 737 | .attr = { .name = __stringify(field), .mode = 0444 }, \ |
c988d2b2 MD |
738 | .show = show_modinfo_##field, \ |
739 | .setup = setup_modinfo_##field, \ | |
740 | .test = modinfo_##field##_exists, \ | |
741 | .free = free_modinfo_##field, \ | |
742 | }; | |
743 | ||
744 | MODINFO_ATTR(version); | |
745 | MODINFO_ATTR(srcversion); | |
746 | ||
e14af7ee AV |
747 | static char last_unloaded_module[MODULE_NAME_LEN+1]; |
748 | ||
03e88ae1 | 749 | #ifdef CONFIG_MODULE_UNLOAD |
eb0c5377 SR |
750 | |
751 | EXPORT_TRACEPOINT_SYMBOL(module_get); | |
752 | ||
e513cc1c MH |
753 | /* MODULE_REF_BASE is the base reference count by kmodule loader. */ |
754 | #define MODULE_REF_BASE 1 | |
755 | ||
1da177e4 | 756 | /* Init the unload section of the module. */ |
9f85a4bb | 757 | static int module_unload_init(struct module *mod) |
1da177e4 | 758 | { |
e513cc1c MH |
759 | /* |
760 | * Initialize reference counter to MODULE_REF_BASE. | |
761 | * refcnt == 0 means module is going. | |
762 | */ | |
763 | atomic_set(&mod->refcnt, MODULE_REF_BASE); | |
9f85a4bb | 764 | |
2c02dfe7 LT |
765 | INIT_LIST_HEAD(&mod->source_list); |
766 | INIT_LIST_HEAD(&mod->target_list); | |
e1783a24 | 767 | |
1da177e4 | 768 | /* Hold reference count during initialization. */ |
e513cc1c | 769 | atomic_inc(&mod->refcnt); |
9f85a4bb RR |
770 | |
771 | return 0; | |
1da177e4 LT |
772 | } |
773 | ||
1da177e4 LT |
774 | /* Does a already use b? */ |
775 | static int already_uses(struct module *a, struct module *b) | |
776 | { | |
777 | struct module_use *use; | |
778 | ||
2c02dfe7 LT |
779 | list_for_each_entry(use, &b->source_list, source_list) { |
780 | if (use->source == a) { | |
5e124169 | 781 | pr_debug("%s uses %s!\n", a->name, b->name); |
1da177e4 LT |
782 | return 1; |
783 | } | |
784 | } | |
5e124169 | 785 | pr_debug("%s does not use %s!\n", a->name, b->name); |
1da177e4 LT |
786 | return 0; |
787 | } | |
788 | ||
2c02dfe7 LT |
789 | /* |
790 | * Module a uses b | |
791 | * - we add 'a' as a "source", 'b' as a "target" of module use | |
792 | * - the module_use is added to the list of 'b' sources (so | |
793 | * 'b' can walk the list to see who sourced them), and of 'a' | |
794 | * targets (so 'a' can see what modules it targets). | |
795 | */ | |
796 | static int add_module_usage(struct module *a, struct module *b) | |
797 | { | |
2c02dfe7 LT |
798 | struct module_use *use; |
799 | ||
5e124169 | 800 | pr_debug("Allocating new usage for %s.\n", a->name); |
2c02dfe7 | 801 | use = kmalloc(sizeof(*use), GFP_ATOMIC); |
9ad04574 | 802 | if (!use) |
2c02dfe7 | 803 | return -ENOMEM; |
2c02dfe7 LT |
804 | |
805 | use->source = a; | |
806 | use->target = b; | |
807 | list_add(&use->source_list, &b->source_list); | |
808 | list_add(&use->target_list, &a->target_list); | |
2c02dfe7 LT |
809 | return 0; |
810 | } | |
811 | ||
75676500 | 812 | /* Module a uses b: caller needs module_mutex() */ |
7ef5264d | 813 | static int ref_module(struct module *a, struct module *b) |
1da177e4 | 814 | { |
c8e21ced | 815 | int err; |
270a6c4c | 816 | |
9bea7f23 | 817 | if (b == NULL || already_uses(a, b)) |
218ce735 | 818 | return 0; |
218ce735 | 819 | |
9bea7f23 RR |
820 | /* If module isn't available, we fail. */ |
821 | err = strong_try_module_get(b); | |
c9a3ba55 | 822 | if (err) |
9bea7f23 | 823 | return err; |
1da177e4 | 824 | |
2c02dfe7 LT |
825 | err = add_module_usage(a, b); |
826 | if (err) { | |
1da177e4 | 827 | module_put(b); |
9bea7f23 | 828 | return err; |
1da177e4 | 829 | } |
9bea7f23 | 830 | return 0; |
1da177e4 LT |
831 | } |
832 | ||
833 | /* Clear the unload stuff of the module. */ | |
834 | static void module_unload_free(struct module *mod) | |
835 | { | |
2c02dfe7 | 836 | struct module_use *use, *tmp; |
1da177e4 | 837 | |
75676500 | 838 | mutex_lock(&module_mutex); |
2c02dfe7 LT |
839 | list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) { |
840 | struct module *i = use->target; | |
5e124169 | 841 | pr_debug("%s unusing %s\n", mod->name, i->name); |
2c02dfe7 LT |
842 | module_put(i); |
843 | list_del(&use->source_list); | |
844 | list_del(&use->target_list); | |
845 | kfree(use); | |
1da177e4 | 846 | } |
75676500 | 847 | mutex_unlock(&module_mutex); |
1da177e4 LT |
848 | } |
849 | ||
850 | #ifdef CONFIG_MODULE_FORCE_UNLOAD | |
fb169793 | 851 | static inline int try_force_unload(unsigned int flags) |
1da177e4 LT |
852 | { |
853 | int ret = (flags & O_TRUNC); | |
854 | if (ret) | |
373d4d09 | 855 | add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE); |
1da177e4 LT |
856 | return ret; |
857 | } | |
858 | #else | |
fb169793 | 859 | static inline int try_force_unload(unsigned int flags) |
1da177e4 LT |
860 | { |
861 | return 0; | |
862 | } | |
863 | #endif /* CONFIG_MODULE_FORCE_UNLOAD */ | |
864 | ||
e513cc1c MH |
865 | /* Try to release refcount of module, 0 means success. */ |
866 | static int try_release_module_ref(struct module *mod) | |
1da177e4 | 867 | { |
e513cc1c | 868 | int ret; |
1da177e4 | 869 | |
e513cc1c MH |
870 | /* Try to decrement refcnt which we set at loading */ |
871 | ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt); | |
872 | BUG_ON(ret < 0); | |
873 | if (ret) | |
874 | /* Someone can put this right now, recover with checking */ | |
875 | ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0); | |
1da177e4 | 876 | |
e513cc1c MH |
877 | return ret; |
878 | } | |
1da177e4 | 879 | |
e513cc1c MH |
880 | static int try_stop_module(struct module *mod, int flags, int *forced) |
881 | { | |
da39ba5e | 882 | /* If it's not unused, quit unless we're forcing. */ |
e513cc1c MH |
883 | if (try_release_module_ref(mod) != 0) { |
884 | *forced = try_force_unload(flags); | |
885 | if (!(*forced)) | |
1da177e4 LT |
886 | return -EWOULDBLOCK; |
887 | } | |
888 | ||
889 | /* Mark it as dying. */ | |
e513cc1c | 890 | mod->state = MODULE_STATE_GOING; |
1da177e4 | 891 | |
e513cc1c | 892 | return 0; |
1da177e4 LT |
893 | } |
894 | ||
d5db139a | 895 | /** |
24389b61 | 896 | * module_refcount() - return the refcount or -1 if unloading |
d5db139a RR |
897 | * @mod: the module we're checking |
898 | * | |
24389b61 | 899 | * Return: |
d5db139a RR |
900 | * -1 if the module is in the process of unloading |
901 | * otherwise the number of references in the kernel to the module | |
902 | */ | |
903 | int module_refcount(struct module *mod) | |
1da177e4 | 904 | { |
d5db139a | 905 | return atomic_read(&mod->refcnt) - MODULE_REF_BASE; |
1da177e4 LT |
906 | } |
907 | EXPORT_SYMBOL(module_refcount); | |
908 | ||
909 | /* This exists whether we can unload or not */ | |
910 | static void free_module(struct module *mod); | |
911 | ||
17da2bd9 HC |
912 | SYSCALL_DEFINE2(delete_module, const char __user *, name_user, |
913 | unsigned int, flags) | |
1da177e4 LT |
914 | { |
915 | struct module *mod; | |
dfff0a06 | 916 | char name[MODULE_NAME_LEN]; |
1da177e4 LT |
917 | int ret, forced = 0; |
918 | ||
3d43321b | 919 | if (!capable(CAP_SYS_MODULE) || modules_disabled) |
dfff0a06 GKH |
920 | return -EPERM; |
921 | ||
922 | if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) | |
923 | return -EFAULT; | |
924 | name[MODULE_NAME_LEN-1] = '\0'; | |
925 | ||
f6276ac9 RGB |
926 | audit_log_kern_module(name); |
927 | ||
3fc1f1e2 TH |
928 | if (mutex_lock_interruptible(&module_mutex) != 0) |
929 | return -EINTR; | |
1da177e4 LT |
930 | |
931 | mod = find_module(name); | |
932 | if (!mod) { | |
933 | ret = -ENOENT; | |
934 | goto out; | |
935 | } | |
936 | ||
2c02dfe7 | 937 | if (!list_empty(&mod->source_list)) { |
1da177e4 LT |
938 | /* Other modules depend on us: get rid of them first. */ |
939 | ret = -EWOULDBLOCK; | |
940 | goto out; | |
941 | } | |
942 | ||
943 | /* Doing init or already dying? */ | |
944 | if (mod->state != MODULE_STATE_LIVE) { | |
3f2b9c9c | 945 | /* FIXME: if (force), slam module count damn the torpedoes */ |
5e124169 | 946 | pr_debug("%s already dying\n", mod->name); |
1da177e4 LT |
947 | ret = -EBUSY; |
948 | goto out; | |
949 | } | |
950 | ||
951 | /* If it has an init func, it must have an exit func to unload */ | |
af49d924 | 952 | if (mod->init && !mod->exit) { |
fb169793 | 953 | forced = try_force_unload(flags); |
1da177e4 LT |
954 | if (!forced) { |
955 | /* This module can't be removed */ | |
956 | ret = -EBUSY; | |
957 | goto out; | |
958 | } | |
959 | } | |
960 | ||
1da177e4 LT |
961 | /* Stop the machine so refcounts can't move and disable module. */ |
962 | ret = try_stop_module(mod, flags, &forced); | |
963 | if (ret != 0) | |
964 | goto out; | |
965 | ||
df4b565e | 966 | mutex_unlock(&module_mutex); |
25985edc | 967 | /* Final destruction now no one is using it. */ |
df4b565e | 968 | if (mod->exit != NULL) |
1da177e4 | 969 | mod->exit(); |
df4b565e PO |
970 | blocking_notifier_call_chain(&module_notify_list, |
971 | MODULE_STATE_GOING, mod); | |
7e545d6e | 972 | klp_module_going(mod); |
7dcd182b JY |
973 | ftrace_release_mod(mod); |
974 | ||
22a9d645 | 975 | async_synchronize_full(); |
75676500 | 976 | |
e14af7ee | 977 | /* Store the name of the last unloaded module for diagnostic purposes */ |
efa5345e | 978 | strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); |
1da177e4 | 979 | |
75676500 | 980 | free_module(mod); |
5d603311 KK |
981 | /* someone could wait for the module in add_unformed_module() */ |
982 | wake_up_all(&module_wq); | |
75676500 RR |
983 | return 0; |
984 | out: | |
6389a385 | 985 | mutex_unlock(&module_mutex); |
1da177e4 LT |
986 | return ret; |
987 | } | |
988 | ||
d1e99d7a | 989 | static inline void print_unload_info(struct seq_file *m, struct module *mod) |
1da177e4 LT |
990 | { |
991 | struct module_use *use; | |
992 | int printed_something = 0; | |
993 | ||
d5db139a | 994 | seq_printf(m, " %i ", module_refcount(mod)); |
1da177e4 | 995 | |
6da0b565 IA |
996 | /* |
997 | * Always include a trailing , so userspace can differentiate | |
998 | * between this and the old multi-field proc format. | |
999 | */ | |
2c02dfe7 | 1000 | list_for_each_entry(use, &mod->source_list, source_list) { |
1da177e4 | 1001 | printed_something = 1; |
2c02dfe7 | 1002 | seq_printf(m, "%s,", use->source->name); |
1da177e4 LT |
1003 | } |
1004 | ||
1da177e4 LT |
1005 | if (mod->init != NULL && mod->exit == NULL) { |
1006 | printed_something = 1; | |
6da0b565 | 1007 | seq_puts(m, "[permanent],"); |
1da177e4 LT |
1008 | } |
1009 | ||
1010 | if (!printed_something) | |
6da0b565 | 1011 | seq_puts(m, "-"); |
1da177e4 LT |
1012 | } |
1013 | ||
1014 | void __symbol_put(const char *symbol) | |
1015 | { | |
0b96615c CH |
1016 | struct find_symbol_arg fsa = { |
1017 | .name = symbol, | |
1018 | .gplok = true, | |
1019 | }; | |
1da177e4 | 1020 | |
24da1cbf | 1021 | preempt_disable(); |
02b2fb45 | 1022 | BUG_ON(!find_symbol(&fsa)); |
0b96615c | 1023 | module_put(fsa.owner); |
24da1cbf | 1024 | preempt_enable(); |
1da177e4 LT |
1025 | } |
1026 | EXPORT_SYMBOL(__symbol_put); | |
1027 | ||
7d1d16e4 | 1028 | /* Note this assumes addr is a function, which it currently always is. */ |
1da177e4 LT |
1029 | void symbol_put_addr(void *addr) |
1030 | { | |
5e376613 | 1031 | struct module *modaddr; |
7d1d16e4 | 1032 | unsigned long a = (unsigned long)dereference_function_descriptor(addr); |
1da177e4 | 1033 | |
7d1d16e4 | 1034 | if (core_kernel_text(a)) |
5e376613 | 1035 | return; |
1da177e4 | 1036 | |
275d7d44 PZ |
1037 | /* |
1038 | * Even though we hold a reference on the module; we still need to | |
1039 | * disable preemption in order to safely traverse the data structure. | |
1040 | */ | |
1041 | preempt_disable(); | |
7d1d16e4 | 1042 | modaddr = __module_text_address(a); |
a6e6abd5 | 1043 | BUG_ON(!modaddr); |
5e376613 | 1044 | module_put(modaddr); |
275d7d44 | 1045 | preempt_enable(); |
1da177e4 LT |
1046 | } |
1047 | EXPORT_SYMBOL_GPL(symbol_put_addr); | |
1048 | ||
1049 | static ssize_t show_refcnt(struct module_attribute *mattr, | |
4befb026 | 1050 | struct module_kobject *mk, char *buffer) |
1da177e4 | 1051 | { |
d5db139a | 1052 | return sprintf(buffer, "%i\n", module_refcount(mk->mod)); |
1da177e4 LT |
1053 | } |
1054 | ||
cca3e707 KS |
1055 | static struct module_attribute modinfo_refcnt = |
1056 | __ATTR(refcnt, 0444, show_refcnt, NULL); | |
1da177e4 | 1057 | |
d53799be SR |
1058 | void __module_get(struct module *module) |
1059 | { | |
1060 | if (module) { | |
1061 | preempt_disable(); | |
2f35c41f | 1062 | atomic_inc(&module->refcnt); |
d53799be SR |
1063 | trace_module_get(module, _RET_IP_); |
1064 | preempt_enable(); | |
1065 | } | |
1066 | } | |
1067 | EXPORT_SYMBOL(__module_get); | |
1068 | ||
1069 | bool try_module_get(struct module *module) | |
1070 | { | |
1071 | bool ret = true; | |
1072 | ||
1073 | if (module) { | |
1074 | preempt_disable(); | |
e513cc1c MH |
1075 | /* Note: here, we can fail to get a reference */ |
1076 | if (likely(module_is_live(module) && | |
1077 | atomic_inc_not_zero(&module->refcnt) != 0)) | |
d53799be | 1078 | trace_module_get(module, _RET_IP_); |
e513cc1c | 1079 | else |
d53799be SR |
1080 | ret = false; |
1081 | ||
1082 | preempt_enable(); | |
1083 | } | |
1084 | return ret; | |
1085 | } | |
1086 | EXPORT_SYMBOL(try_module_get); | |
1087 | ||
f6a57033 AV |
1088 | void module_put(struct module *module) |
1089 | { | |
e513cc1c MH |
1090 | int ret; |
1091 | ||
f6a57033 | 1092 | if (module) { |
e1783a24 | 1093 | preempt_disable(); |
e513cc1c MH |
1094 | ret = atomic_dec_if_positive(&module->refcnt); |
1095 | WARN_ON(ret < 0); /* Failed to put refcount */ | |
ae832d1e | 1096 | trace_module_put(module, _RET_IP_); |
e1783a24 | 1097 | preempt_enable(); |
f6a57033 AV |
1098 | } |
1099 | } | |
1100 | EXPORT_SYMBOL(module_put); | |
1101 | ||
1da177e4 | 1102 | #else /* !CONFIG_MODULE_UNLOAD */ |
d1e99d7a | 1103 | static inline void print_unload_info(struct seq_file *m, struct module *mod) |
1da177e4 LT |
1104 | { |
1105 | /* We don't know the usage count, or what modules are using. */ | |
6da0b565 | 1106 | seq_puts(m, " - -"); |
1da177e4 LT |
1107 | } |
1108 | ||
1109 | static inline void module_unload_free(struct module *mod) | |
1110 | { | |
1111 | } | |
1112 | ||
7ef5264d | 1113 | static int ref_module(struct module *a, struct module *b) |
1da177e4 | 1114 | { |
9bea7f23 | 1115 | return strong_try_module_get(b); |
1da177e4 LT |
1116 | } |
1117 | ||
9f85a4bb | 1118 | static inline int module_unload_init(struct module *mod) |
1da177e4 | 1119 | { |
9f85a4bb | 1120 | return 0; |
1da177e4 LT |
1121 | } |
1122 | #endif /* CONFIG_MODULE_UNLOAD */ | |
1123 | ||
53999bf3 KW |
1124 | static size_t module_flags_taint(struct module *mod, char *buf) |
1125 | { | |
1126 | size_t l = 0; | |
7fd8329b PM |
1127 | int i; |
1128 | ||
1129 | for (i = 0; i < TAINT_FLAGS_COUNT; i++) { | |
1130 | if (taint_flags[i].module && test_bit(i, &mod->taints)) | |
5eb7c0d0 | 1131 | buf[l++] = taint_flags[i].c_true; |
7fd8329b | 1132 | } |
53999bf3 | 1133 | |
53999bf3 KW |
1134 | return l; |
1135 | } | |
1136 | ||
1f71740a | 1137 | static ssize_t show_initstate(struct module_attribute *mattr, |
4befb026 | 1138 | struct module_kobject *mk, char *buffer) |
1f71740a KS |
1139 | { |
1140 | const char *state = "unknown"; | |
1141 | ||
4befb026 | 1142 | switch (mk->mod->state) { |
1f71740a KS |
1143 | case MODULE_STATE_LIVE: |
1144 | state = "live"; | |
1145 | break; | |
1146 | case MODULE_STATE_COMING: | |
1147 | state = "coming"; | |
1148 | break; | |
1149 | case MODULE_STATE_GOING: | |
1150 | state = "going"; | |
1151 | break; | |
0d21b0e3 RR |
1152 | default: |
1153 | BUG(); | |
1f71740a KS |
1154 | } |
1155 | return sprintf(buffer, "%s\n", state); | |
1156 | } | |
1157 | ||
cca3e707 KS |
1158 | static struct module_attribute modinfo_initstate = |
1159 | __ATTR(initstate, 0444, show_initstate, NULL); | |
1f71740a | 1160 | |
88bfa324 KS |
1161 | static ssize_t store_uevent(struct module_attribute *mattr, |
1162 | struct module_kobject *mk, | |
1163 | const char *buffer, size_t count) | |
1164 | { | |
df44b479 PR |
1165 | int rc; |
1166 | ||
1167 | rc = kobject_synth_uevent(&mk->kobj, buffer, count); | |
1168 | return rc ? rc : count; | |
88bfa324 KS |
1169 | } |
1170 | ||
cca3e707 KS |
1171 | struct module_attribute module_uevent = |
1172 | __ATTR(uevent, 0200, NULL, store_uevent); | |
1173 | ||
1174 | static ssize_t show_coresize(struct module_attribute *mattr, | |
1175 | struct module_kobject *mk, char *buffer) | |
1176 | { | |
7523e4dc | 1177 | return sprintf(buffer, "%u\n", mk->mod->core_layout.size); |
cca3e707 KS |
1178 | } |
1179 | ||
1180 | static struct module_attribute modinfo_coresize = | |
1181 | __ATTR(coresize, 0444, show_coresize, NULL); | |
1182 | ||
1183 | static ssize_t show_initsize(struct module_attribute *mattr, | |
1184 | struct module_kobject *mk, char *buffer) | |
1185 | { | |
7523e4dc | 1186 | return sprintf(buffer, "%u\n", mk->mod->init_layout.size); |
cca3e707 KS |
1187 | } |
1188 | ||
1189 | static struct module_attribute modinfo_initsize = | |
1190 | __ATTR(initsize, 0444, show_initsize, NULL); | |
1191 | ||
1192 | static ssize_t show_taint(struct module_attribute *mattr, | |
1193 | struct module_kobject *mk, char *buffer) | |
1194 | { | |
1195 | size_t l; | |
1196 | ||
1197 | l = module_flags_taint(mk->mod, buffer); | |
1198 | buffer[l++] = '\n'; | |
1199 | return l; | |
1200 | } | |
1201 | ||
1202 | static struct module_attribute modinfo_taint = | |
1203 | __ATTR(taint, 0444, show_taint, NULL); | |
88bfa324 | 1204 | |
03e88ae1 | 1205 | static struct module_attribute *modinfo_attrs[] = { |
cca3e707 | 1206 | &module_uevent, |
03e88ae1 GKH |
1207 | &modinfo_version, |
1208 | &modinfo_srcversion, | |
cca3e707 KS |
1209 | &modinfo_initstate, |
1210 | &modinfo_coresize, | |
1211 | &modinfo_initsize, | |
1212 | &modinfo_taint, | |
03e88ae1 | 1213 | #ifdef CONFIG_MODULE_UNLOAD |
cca3e707 | 1214 | &modinfo_refcnt, |
03e88ae1 GKH |
1215 | #endif |
1216 | NULL, | |
1217 | }; | |
1218 | ||
1da177e4 LT |
1219 | static const char vermagic[] = VERMAGIC_STRING; |
1220 | ||
c6e665c8 | 1221 | static int try_to_force_load(struct module *mod, const char *reason) |
826e4506 LT |
1222 | { |
1223 | #ifdef CONFIG_MODULE_FORCE_LOAD | |
25ddbb18 | 1224 | if (!test_taint(TAINT_FORCED_MODULE)) |
bddb12b3 | 1225 | pr_warn("%s: %s: kernel tainted.\n", mod->name, reason); |
373d4d09 | 1226 | add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE); |
826e4506 LT |
1227 | return 0; |
1228 | #else | |
1229 | return -ENOEXEC; | |
1230 | #endif | |
1231 | } | |
1232 | ||
1da177e4 | 1233 | #ifdef CONFIG_MODVERSIONS |
71810db2 AB |
1234 | |
1235 | static u32 resolve_rel_crc(const s32 *crc) | |
d4703aef | 1236 | { |
71810db2 | 1237 | return *(u32 *)((void *)crc + *crc); |
d4703aef RR |
1238 | } |
1239 | ||
49019426 | 1240 | static int check_version(const struct load_info *info, |
1da177e4 | 1241 | const char *symname, |
6da0b565 | 1242 | struct module *mod, |
71810db2 | 1243 | const s32 *crc) |
1da177e4 | 1244 | { |
49019426 KC |
1245 | Elf_Shdr *sechdrs = info->sechdrs; |
1246 | unsigned int versindex = info->index.vers; | |
1da177e4 LT |
1247 | unsigned int i, num_versions; |
1248 | struct modversion_info *versions; | |
1249 | ||
1250 | /* Exporting module didn't supply crcs? OK, we're already tainted. */ | |
1251 | if (!crc) | |
1252 | return 1; | |
1253 | ||
a5dd6970 RR |
1254 | /* No versions at all? modprobe --force does this. */ |
1255 | if (versindex == 0) | |
1256 | return try_to_force_load(mod, symname) == 0; | |
1257 | ||
1da177e4 LT |
1258 | versions = (void *) sechdrs[versindex].sh_addr; |
1259 | num_versions = sechdrs[versindex].sh_size | |
1260 | / sizeof(struct modversion_info); | |
1261 | ||
1262 | for (i = 0; i < num_versions; i++) { | |
71810db2 AB |
1263 | u32 crcval; |
1264 | ||
1da177e4 LT |
1265 | if (strcmp(versions[i].name, symname) != 0) |
1266 | continue; | |
1267 | ||
71810db2 AB |
1268 | if (IS_ENABLED(CONFIG_MODULE_REL_CRCS)) |
1269 | crcval = resolve_rel_crc(crc); | |
1270 | else | |
1271 | crcval = *crc; | |
1272 | if (versions[i].crc == crcval) | |
1da177e4 | 1273 | return 1; |
71810db2 AB |
1274 | pr_debug("Found checksum %X vs module %lX\n", |
1275 | crcval, versions[i].crc); | |
826e4506 | 1276 | goto bad_version; |
1da177e4 | 1277 | } |
826e4506 | 1278 | |
faaae2a5 | 1279 | /* Broken toolchain. Warn once, then let it go.. */ |
3e2e857f | 1280 | pr_warn_once("%s: no symbol version for %s\n", info->name, symname); |
faaae2a5 | 1281 | return 1; |
826e4506 LT |
1282 | |
1283 | bad_version: | |
6da0b565 | 1284 | pr_warn("%s: disagrees about version of symbol %s\n", |
3e2e857f | 1285 | info->name, symname); |
826e4506 | 1286 | return 0; |
1da177e4 LT |
1287 | } |
1288 | ||
49019426 | 1289 | static inline int check_modstruct_version(const struct load_info *info, |
1da177e4 LT |
1290 | struct module *mod) |
1291 | { | |
0b96615c CH |
1292 | struct find_symbol_arg fsa = { |
1293 | .name = "module_layout", | |
1294 | .gplok = true, | |
1295 | }; | |
1da177e4 | 1296 | |
926a59b1 PZ |
1297 | /* |
1298 | * Since this should be found in kernel (which can't be removed), no | |
1299 | * locking is necessary -- use preempt_disable() to placate lockdep. | |
1300 | */ | |
1301 | preempt_disable(); | |
0b96615c | 1302 | if (!find_symbol(&fsa)) { |
926a59b1 | 1303 | preempt_enable(); |
1da177e4 | 1304 | BUG(); |
926a59b1 PZ |
1305 | } |
1306 | preempt_enable(); | |
0b96615c | 1307 | return check_version(info, "module_layout", mod, fsa.crc); |
1da177e4 LT |
1308 | } |
1309 | ||
91e37a79 RR |
1310 | /* First part is kernel version, which we ignore if module has crcs. */ |
1311 | static inline int same_magic(const char *amagic, const char *bmagic, | |
1312 | bool has_crcs) | |
1da177e4 | 1313 | { |
91e37a79 RR |
1314 | if (has_crcs) { |
1315 | amagic += strcspn(amagic, " "); | |
1316 | bmagic += strcspn(bmagic, " "); | |
1317 | } | |
1da177e4 LT |
1318 | return strcmp(amagic, bmagic) == 0; |
1319 | } | |
1320 | #else | |
49019426 | 1321 | static inline int check_version(const struct load_info *info, |
1da177e4 | 1322 | const char *symname, |
6da0b565 | 1323 | struct module *mod, |
71810db2 | 1324 | const s32 *crc) |
1da177e4 LT |
1325 | { |
1326 | return 1; | |
1327 | } | |
1328 | ||
49019426 | 1329 | static inline int check_modstruct_version(const struct load_info *info, |
1da177e4 LT |
1330 | struct module *mod) |
1331 | { | |
1332 | return 1; | |
1333 | } | |
1334 | ||
91e37a79 RR |
1335 | static inline int same_magic(const char *amagic, const char *bmagic, |
1336 | bool has_crcs) | |
1da177e4 LT |
1337 | { |
1338 | return strcmp(amagic, bmagic) == 0; | |
1339 | } | |
1340 | #endif /* CONFIG_MODVERSIONS */ | |
1341 | ||
8651ec01 MM |
1342 | static char *get_modinfo(const struct load_info *info, const char *tag); |
1343 | static char *get_next_modinfo(const struct load_info *info, const char *tag, | |
1344 | char *prev); | |
1345 | ||
1346 | static int verify_namespace_is_imported(const struct load_info *info, | |
1347 | const struct kernel_symbol *sym, | |
1348 | struct module *mod) | |
1349 | { | |
1350 | const char *namespace; | |
1351 | char *imported_namespace; | |
1352 | ||
1353 | namespace = kernel_symbol_namespace(sym); | |
c3a6cf19 | 1354 | if (namespace && namespace[0]) { |
8651ec01 MM |
1355 | imported_namespace = get_modinfo(info, "import_ns"); |
1356 | while (imported_namespace) { | |
1357 | if (strcmp(namespace, imported_namespace) == 0) | |
1358 | return 0; | |
1359 | imported_namespace = get_next_modinfo( | |
1360 | info, "import_ns", imported_namespace); | |
1361 | } | |
3d52ec5e MM |
1362 | #ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS |
1363 | pr_warn( | |
1364 | #else | |
1365 | pr_err( | |
1366 | #endif | |
1367 | "%s: module uses symbol (%s) from namespace %s, but does not import it.\n", | |
1368 | mod->name, kernel_symbol_name(sym), namespace); | |
1369 | #ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS | |
8651ec01 | 1370 | return -EINVAL; |
3d52ec5e | 1371 | #endif |
8651ec01 MM |
1372 | } |
1373 | return 0; | |
1374 | } | |
1375 | ||
262e6ae7 CH |
1376 | static bool inherit_taint(struct module *mod, struct module *owner) |
1377 | { | |
1378 | if (!owner || !test_bit(TAINT_PROPRIETARY_MODULE, &owner->taints)) | |
1379 | return true; | |
1380 | ||
1381 | if (mod->using_gplonly_symbols) { | |
1382 | pr_err("%s: module using GPL-only symbols uses symbols from proprietary module %s.\n", | |
1383 | mod->name, owner->name); | |
1384 | return false; | |
1385 | } | |
1386 | ||
1387 | if (!test_bit(TAINT_PROPRIETARY_MODULE, &mod->taints)) { | |
1388 | pr_warn("%s: module uses symbols from proprietary module %s, inheriting taint.\n", | |
1389 | mod->name, owner->name); | |
1390 | set_bit(TAINT_PROPRIETARY_MODULE, &mod->taints); | |
1391 | } | |
1392 | return true; | |
1393 | } | |
8651ec01 | 1394 | |
75676500 | 1395 | /* Resolve a symbol for this module. I.e. if we find one, record usage. */ |
49668688 RR |
1396 | static const struct kernel_symbol *resolve_symbol(struct module *mod, |
1397 | const struct load_info *info, | |
414fd31b | 1398 | const char *name, |
9bea7f23 | 1399 | char ownername[]) |
1da177e4 | 1400 | { |
0b96615c CH |
1401 | struct find_symbol_arg fsa = { |
1402 | .name = name, | |
1403 | .gplok = !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), | |
1404 | .warn = true, | |
1405 | }; | |
9bea7f23 | 1406 | int err; |
1da177e4 | 1407 | |
d64810f5 PZ |
1408 | /* |
1409 | * The module_mutex should not be a heavily contended lock; | |
1410 | * if we get the occasional sleep here, we'll go an extra iteration | |
1411 | * in the wait_event_interruptible(), which is harmless. | |
1412 | */ | |
1413 | sched_annotate_sleep(); | |
75676500 | 1414 | mutex_lock(&module_mutex); |
0b96615c | 1415 | if (!find_symbol(&fsa)) |
9bea7f23 RR |
1416 | goto unlock; |
1417 | ||
0b96615c | 1418 | if (fsa.license == GPL_ONLY) |
262e6ae7 CH |
1419 | mod->using_gplonly_symbols = true; |
1420 | ||
0b96615c CH |
1421 | if (!inherit_taint(mod, fsa.owner)) { |
1422 | fsa.sym = NULL; | |
262e6ae7 CH |
1423 | goto getname; |
1424 | } | |
1425 | ||
0b96615c CH |
1426 | if (!check_version(info, name, mod, fsa.crc)) { |
1427 | fsa.sym = ERR_PTR(-EINVAL); | |
9bea7f23 | 1428 | goto getname; |
1da177e4 | 1429 | } |
9bea7f23 | 1430 | |
0b96615c | 1431 | err = verify_namespace_is_imported(info, fsa.sym, mod); |
8651ec01 | 1432 | if (err) { |
0b96615c | 1433 | fsa.sym = ERR_PTR(err); |
8651ec01 MM |
1434 | goto getname; |
1435 | } | |
1436 | ||
0b96615c | 1437 | err = ref_module(mod, fsa.owner); |
9bea7f23 | 1438 | if (err) { |
0b96615c | 1439 | fsa.sym = ERR_PTR(err); |
9bea7f23 RR |
1440 | goto getname; |
1441 | } | |
1442 | ||
1443 | getname: | |
1444 | /* We must make copy under the lock if we failed to get ref. */ | |
0b96615c | 1445 | strncpy(ownername, module_name(fsa.owner), MODULE_NAME_LEN); |
9bea7f23 | 1446 | unlock: |
75676500 | 1447 | mutex_unlock(&module_mutex); |
0b96615c | 1448 | return fsa.sym; |
1da177e4 LT |
1449 | } |
1450 | ||
49668688 RR |
1451 | static const struct kernel_symbol * |
1452 | resolve_symbol_wait(struct module *mod, | |
1453 | const struct load_info *info, | |
1454 | const char *name) | |
9bea7f23 RR |
1455 | { |
1456 | const struct kernel_symbol *ksym; | |
49668688 | 1457 | char owner[MODULE_NAME_LEN]; |
9bea7f23 RR |
1458 | |
1459 | if (wait_event_interruptible_timeout(module_wq, | |
49668688 RR |
1460 | !IS_ERR(ksym = resolve_symbol(mod, info, name, owner)) |
1461 | || PTR_ERR(ksym) != -EBUSY, | |
9bea7f23 | 1462 | 30 * HZ) <= 0) { |
bddb12b3 AM |
1463 | pr_warn("%s: gave up waiting for init of module %s.\n", |
1464 | mod->name, owner); | |
9bea7f23 RR |
1465 | } |
1466 | return ksym; | |
1467 | } | |
1468 | ||
9294523e SB |
1469 | #ifdef CONFIG_KALLSYMS |
1470 | static inline bool sect_empty(const Elf_Shdr *sect) | |
1471 | { | |
1472 | return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0; | |
1473 | } | |
1474 | #endif | |
1475 | ||
1da177e4 LT |
1476 | /* |
1477 | * /sys/module/foo/sections stuff | |
1478 | * J. Corbet <corbet@lwn.net> | |
1479 | */ | |
8f6d0378 | 1480 | #ifdef CONFIG_SYSFS |
10b465aa | 1481 | |
8f6d0378 | 1482 | #ifdef CONFIG_KALLSYMS |
6da0b565 | 1483 | struct module_sect_attr { |
ed66f991 | 1484 | struct bin_attribute battr; |
a58730c4 RR |
1485 | unsigned long address; |
1486 | }; | |
1487 | ||
6da0b565 | 1488 | struct module_sect_attrs { |
a58730c4 RR |
1489 | struct attribute_group grp; |
1490 | unsigned int nsections; | |
0f742266 | 1491 | struct module_sect_attr attrs[]; |
a58730c4 RR |
1492 | }; |
1493 | ||
11990a5b | 1494 | #define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4)) |
ed66f991 KC |
1495 | static ssize_t module_sect_read(struct file *file, struct kobject *kobj, |
1496 | struct bin_attribute *battr, | |
1497 | char *buf, loff_t pos, size_t count) | |
1da177e4 LT |
1498 | { |
1499 | struct module_sect_attr *sattr = | |
ed66f991 | 1500 | container_of(battr, struct module_sect_attr, battr); |
11990a5b KC |
1501 | char bounce[MODULE_SECT_READ_SIZE + 1]; |
1502 | size_t wrote; | |
ed66f991 KC |
1503 | |
1504 | if (pos != 0) | |
1505 | return -EINVAL; | |
1506 | ||
11990a5b KC |
1507 | /* |
1508 | * Since we're a binary read handler, we must account for the | |
1509 | * trailing NUL byte that sprintf will write: if "buf" is | |
1510 | * too small to hold the NUL, or the NUL is exactly the last | |
1511 | * byte, the read will look like it got truncated by one byte. | |
1512 | * Since there is no way to ask sprintf nicely to not write | |
1513 | * the NUL, we have to use a bounce buffer. | |
1514 | */ | |
1515 | wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n", | |
1516 | kallsyms_show_value(file->f_cred) | |
1517 | ? (void *)sattr->address : NULL); | |
1518 | count = min(count, wrote); | |
1519 | memcpy(buf, bounce, count); | |
1520 | ||
1521 | return count; | |
1da177e4 LT |
1522 | } |
1523 | ||
04b1db9f IN |
1524 | static void free_sect_attrs(struct module_sect_attrs *sect_attrs) |
1525 | { | |
a58730c4 | 1526 | unsigned int section; |
04b1db9f IN |
1527 | |
1528 | for (section = 0; section < sect_attrs->nsections; section++) | |
ed66f991 | 1529 | kfree(sect_attrs->attrs[section].battr.attr.name); |
04b1db9f IN |
1530 | kfree(sect_attrs); |
1531 | } | |
1532 | ||
8f6d0378 | 1533 | static void add_sect_attrs(struct module *mod, const struct load_info *info) |
1da177e4 LT |
1534 | { |
1535 | unsigned int nloaded = 0, i, size[2]; | |
1536 | struct module_sect_attrs *sect_attrs; | |
1537 | struct module_sect_attr *sattr; | |
ed66f991 | 1538 | struct bin_attribute **gattr; |
22a8bdeb | 1539 | |
1da177e4 | 1540 | /* Count loaded sections and allocate structures */ |
8f6d0378 RR |
1541 | for (i = 0; i < info->hdr->e_shnum; i++) |
1542 | if (!sect_empty(&info->sechdrs[i])) | |
1da177e4 | 1543 | nloaded++; |
8d1b73dd | 1544 | size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded), |
ed66f991 KC |
1545 | sizeof(sect_attrs->grp.bin_attrs[0])); |
1546 | size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]); | |
04b1db9f IN |
1547 | sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); |
1548 | if (sect_attrs == NULL) | |
1da177e4 LT |
1549 | return; |
1550 | ||
1551 | /* Setup section attributes. */ | |
1552 | sect_attrs->grp.name = "sections"; | |
ed66f991 | 1553 | sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0]; |
1da177e4 | 1554 | |
04b1db9f | 1555 | sect_attrs->nsections = 0; |
1da177e4 | 1556 | sattr = §_attrs->attrs[0]; |
ed66f991 | 1557 | gattr = §_attrs->grp.bin_attrs[0]; |
8f6d0378 RR |
1558 | for (i = 0; i < info->hdr->e_shnum; i++) { |
1559 | Elf_Shdr *sec = &info->sechdrs[i]; | |
1560 | if (sect_empty(sec)) | |
35dead42 | 1561 | continue; |
ed66f991 | 1562 | sysfs_bin_attr_init(&sattr->battr); |
8f6d0378 | 1563 | sattr->address = sec->sh_addr; |
ed66f991 KC |
1564 | sattr->battr.attr.name = |
1565 | kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL); | |
1566 | if (sattr->battr.attr.name == NULL) | |
04b1db9f IN |
1567 | goto out; |
1568 | sect_attrs->nsections++; | |
ed66f991 | 1569 | sattr->battr.read = module_sect_read; |
11990a5b | 1570 | sattr->battr.size = MODULE_SECT_READ_SIZE; |
ed66f991 KC |
1571 | sattr->battr.attr.mode = 0400; |
1572 | *(gattr++) = &(sattr++)->battr; | |
1da177e4 LT |
1573 | } |
1574 | *gattr = NULL; | |
1575 | ||
1576 | if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) | |
1577 | goto out; | |
1578 | ||
1579 | mod->sect_attrs = sect_attrs; | |
1580 | return; | |
1581 | out: | |
04b1db9f | 1582 | free_sect_attrs(sect_attrs); |
1da177e4 LT |
1583 | } |
1584 | ||
1585 | static void remove_sect_attrs(struct module *mod) | |
1586 | { | |
1587 | if (mod->sect_attrs) { | |
1588 | sysfs_remove_group(&mod->mkobj.kobj, | |
1589 | &mod->sect_attrs->grp); | |
24b9f0d2 SS |
1590 | /* |
1591 | * We are positive that no one is using any sect attrs | |
1592 | * at this point. Deallocate immediately. | |
1593 | */ | |
04b1db9f | 1594 | free_sect_attrs(mod->sect_attrs); |
1da177e4 LT |
1595 | mod->sect_attrs = NULL; |
1596 | } | |
1597 | } | |
1598 | ||
6d760133 RM |
1599 | /* |
1600 | * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. | |
1601 | */ | |
1602 | ||
1603 | struct module_notes_attrs { | |
1604 | struct kobject *dir; | |
1605 | unsigned int notes; | |
0f742266 | 1606 | struct bin_attribute attrs[]; |
6d760133 RM |
1607 | }; |
1608 | ||
2c3c8bea | 1609 | static ssize_t module_notes_read(struct file *filp, struct kobject *kobj, |
6d760133 RM |
1610 | struct bin_attribute *bin_attr, |
1611 | char *buf, loff_t pos, size_t count) | |
1612 | { | |
1613 | /* | |
1614 | * The caller checked the pos and count against our size. | |
1615 | */ | |
1616 | memcpy(buf, bin_attr->private + pos, count); | |
1617 | return count; | |
1618 | } | |
1619 | ||
1620 | static void free_notes_attrs(struct module_notes_attrs *notes_attrs, | |
1621 | unsigned int i) | |
1622 | { | |
1623 | if (notes_attrs->dir) { | |
1624 | while (i-- > 0) | |
1625 | sysfs_remove_bin_file(notes_attrs->dir, | |
1626 | ¬es_attrs->attrs[i]); | |
e9432093 | 1627 | kobject_put(notes_attrs->dir); |
6d760133 RM |
1628 | } |
1629 | kfree(notes_attrs); | |
1630 | } | |
1631 | ||
8f6d0378 | 1632 | static void add_notes_attrs(struct module *mod, const struct load_info *info) |
6d760133 RM |
1633 | { |
1634 | unsigned int notes, loaded, i; | |
1635 | struct module_notes_attrs *notes_attrs; | |
1636 | struct bin_attribute *nattr; | |
1637 | ||
ea6bff36 IM |
1638 | /* failed to create section attributes, so can't create notes */ |
1639 | if (!mod->sect_attrs) | |
1640 | return; | |
1641 | ||
6d760133 RM |
1642 | /* Count notes sections and allocate structures. */ |
1643 | notes = 0; | |
8f6d0378 RR |
1644 | for (i = 0; i < info->hdr->e_shnum; i++) |
1645 | if (!sect_empty(&info->sechdrs[i]) && | |
1646 | (info->sechdrs[i].sh_type == SHT_NOTE)) | |
6d760133 RM |
1647 | ++notes; |
1648 | ||
1649 | if (notes == 0) | |
1650 | return; | |
1651 | ||
acafe7e3 | 1652 | notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes), |
6d760133 RM |
1653 | GFP_KERNEL); |
1654 | if (notes_attrs == NULL) | |
1655 | return; | |
1656 | ||
1657 | notes_attrs->notes = notes; | |
1658 | nattr = ¬es_attrs->attrs[0]; | |
8f6d0378 RR |
1659 | for (loaded = i = 0; i < info->hdr->e_shnum; ++i) { |
1660 | if (sect_empty(&info->sechdrs[i])) | |
6d760133 | 1661 | continue; |
8f6d0378 | 1662 | if (info->sechdrs[i].sh_type == SHT_NOTE) { |
361795b1 | 1663 | sysfs_bin_attr_init(nattr); |
ed66f991 | 1664 | nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name; |
6d760133 | 1665 | nattr->attr.mode = S_IRUGO; |
8f6d0378 RR |
1666 | nattr->size = info->sechdrs[i].sh_size; |
1667 | nattr->private = (void *) info->sechdrs[i].sh_addr; | |
6d760133 RM |
1668 | nattr->read = module_notes_read; |
1669 | ++nattr; | |
1670 | } | |
1671 | ++loaded; | |
1672 | } | |
1673 | ||
4ff6abff | 1674 | notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); |
6d760133 RM |
1675 | if (!notes_attrs->dir) |
1676 | goto out; | |
1677 | ||
1678 | for (i = 0; i < notes; ++i) | |
1679 | if (sysfs_create_bin_file(notes_attrs->dir, | |
1680 | ¬es_attrs->attrs[i])) | |
1681 | goto out; | |
1682 | ||
1683 | mod->notes_attrs = notes_attrs; | |
1684 | return; | |
1685 | ||
1686 | out: | |
1687 | free_notes_attrs(notes_attrs, i); | |
1688 | } | |
1689 | ||
1690 | static void remove_notes_attrs(struct module *mod) | |
1691 | { | |
1692 | if (mod->notes_attrs) | |
1693 | free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); | |
1694 | } | |
1695 | ||
1da177e4 | 1696 | #else |
04b1db9f | 1697 | |
8f6d0378 RR |
1698 | static inline void add_sect_attrs(struct module *mod, |
1699 | const struct load_info *info) | |
1da177e4 LT |
1700 | { |
1701 | } | |
1702 | ||
1703 | static inline void remove_sect_attrs(struct module *mod) | |
1704 | { | |
1705 | } | |
6d760133 | 1706 | |
8f6d0378 RR |
1707 | static inline void add_notes_attrs(struct module *mod, |
1708 | const struct load_info *info) | |
6d760133 RM |
1709 | { |
1710 | } | |
1711 | ||
1712 | static inline void remove_notes_attrs(struct module *mod) | |
1713 | { | |
1714 | } | |
8f6d0378 | 1715 | #endif /* CONFIG_KALLSYMS */ |
1da177e4 | 1716 | |
1ba5c08b | 1717 | static void del_usage_links(struct module *mod) |
80a3d1bb RR |
1718 | { |
1719 | #ifdef CONFIG_MODULE_UNLOAD | |
1720 | struct module_use *use; | |
80a3d1bb | 1721 | |
75676500 | 1722 | mutex_lock(&module_mutex); |
1ba5c08b CL |
1723 | list_for_each_entry(use, &mod->target_list, target_list) |
1724 | sysfs_remove_link(use->target->holders_dir, mod->name); | |
75676500 | 1725 | mutex_unlock(&module_mutex); |
80a3d1bb RR |
1726 | #endif |
1727 | } | |
1728 | ||
1ba5c08b | 1729 | static int add_usage_links(struct module *mod) |
80a3d1bb | 1730 | { |
1ba5c08b | 1731 | int ret = 0; |
80a3d1bb RR |
1732 | #ifdef CONFIG_MODULE_UNLOAD |
1733 | struct module_use *use; | |
1734 | ||
75676500 | 1735 | mutex_lock(&module_mutex); |
1ba5c08b CL |
1736 | list_for_each_entry(use, &mod->target_list, target_list) { |
1737 | ret = sysfs_create_link(use->target->holders_dir, | |
1738 | &mod->mkobj.kobj, mod->name); | |
1739 | if (ret) | |
1740 | break; | |
1741 | } | |
75676500 | 1742 | mutex_unlock(&module_mutex); |
1ba5c08b CL |
1743 | if (ret) |
1744 | del_usage_links(mod); | |
80a3d1bb | 1745 | #endif |
1ba5c08b | 1746 | return ret; |
80a3d1bb RR |
1747 | } |
1748 | ||
bc6f2a75 Y |
1749 | static void module_remove_modinfo_attrs(struct module *mod, int end); |
1750 | ||
6407ebb2 | 1751 | static int module_add_modinfo_attrs(struct module *mod) |
c988d2b2 MD |
1752 | { |
1753 | struct module_attribute *attr; | |
03e88ae1 | 1754 | struct module_attribute *temp_attr; |
c988d2b2 MD |
1755 | int error = 0; |
1756 | int i; | |
1757 | ||
03e88ae1 GKH |
1758 | mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * |
1759 | (ARRAY_SIZE(modinfo_attrs) + 1)), | |
1760 | GFP_KERNEL); | |
1761 | if (!mod->modinfo_attrs) | |
1762 | return -ENOMEM; | |
1763 | ||
1764 | temp_attr = mod->modinfo_attrs; | |
bc6f2a75 | 1765 | for (i = 0; (attr = modinfo_attrs[i]); i++) { |
c75b590d | 1766 | if (!attr->test || attr->test(mod)) { |
03e88ae1 | 1767 | memcpy(temp_attr, attr, sizeof(*temp_attr)); |
361795b1 | 1768 | sysfs_attr_init(&temp_attr->attr); |
6da0b565 IA |
1769 | error = sysfs_create_file(&mod->mkobj.kobj, |
1770 | &temp_attr->attr); | |
bc6f2a75 Y |
1771 | if (error) |
1772 | goto error_out; | |
03e88ae1 GKH |
1773 | ++temp_attr; |
1774 | } | |
c988d2b2 | 1775 | } |
bc6f2a75 Y |
1776 | |
1777 | return 0; | |
1778 | ||
1779 | error_out: | |
1780 | if (i > 0) | |
1781 | module_remove_modinfo_attrs(mod, --i); | |
f6d061d6 Y |
1782 | else |
1783 | kfree(mod->modinfo_attrs); | |
c988d2b2 MD |
1784 | return error; |
1785 | } | |
1786 | ||
bc6f2a75 | 1787 | static void module_remove_modinfo_attrs(struct module *mod, int end) |
c988d2b2 MD |
1788 | { |
1789 | struct module_attribute *attr; | |
1790 | int i; | |
1791 | ||
03e88ae1 | 1792 | for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { |
bc6f2a75 Y |
1793 | if (end >= 0 && i > end) |
1794 | break; | |
03e88ae1 GKH |
1795 | /* pick a field to test for end of list */ |
1796 | if (!attr->attr.name) | |
1797 | break; | |
6da0b565 | 1798 | sysfs_remove_file(&mod->mkobj.kobj, &attr->attr); |
03e88ae1 GKH |
1799 | if (attr->free) |
1800 | attr->free(mod); | |
c988d2b2 | 1801 | } |
03e88ae1 | 1802 | kfree(mod->modinfo_attrs); |
c988d2b2 | 1803 | } |
1da177e4 | 1804 | |
942e4431 LZ |
1805 | static void mod_kobject_put(struct module *mod) |
1806 | { | |
1807 | DECLARE_COMPLETION_ONSTACK(c); | |
1808 | mod->mkobj.kobj_completion = &c; | |
1809 | kobject_put(&mod->mkobj.kobj); | |
1810 | wait_for_completion(&c); | |
1811 | } | |
1812 | ||
6407ebb2 | 1813 | static int mod_sysfs_init(struct module *mod) |
1da177e4 LT |
1814 | { |
1815 | int err; | |
6494a93d | 1816 | struct kobject *kobj; |
1da177e4 | 1817 | |
823bccfc | 1818 | if (!module_sysfs_initialized) { |
bddb12b3 | 1819 | pr_err("%s: module sysfs not initialized\n", mod->name); |
1cc5f714 ES |
1820 | err = -EINVAL; |
1821 | goto out; | |
1822 | } | |
6494a93d GKH |
1823 | |
1824 | kobj = kset_find_obj(module_kset, mod->name); | |
1825 | if (kobj) { | |
bddb12b3 | 1826 | pr_err("%s: module is already loaded\n", mod->name); |
6494a93d GKH |
1827 | kobject_put(kobj); |
1828 | err = -EINVAL; | |
1829 | goto out; | |
1830 | } | |
1831 | ||
1da177e4 | 1832 | mod->mkobj.mod = mod; |
e17e0f51 | 1833 | |
ac3c8141 GKH |
1834 | memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); |
1835 | mod->mkobj.kobj.kset = module_kset; | |
1836 | err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, | |
1837 | "%s", mod->name); | |
1838 | if (err) | |
942e4431 | 1839 | mod_kobject_put(mod); |
270a6c4c KS |
1840 | |
1841 | out: | |
1842 | return err; | |
1843 | } | |
1844 | ||
6407ebb2 | 1845 | static int mod_sysfs_setup(struct module *mod, |
8f6d0378 | 1846 | const struct load_info *info, |
270a6c4c KS |
1847 | struct kernel_param *kparam, |
1848 | unsigned int num_params) | |
1849 | { | |
1850 | int err; | |
1851 | ||
80a3d1bb RR |
1852 | err = mod_sysfs_init(mod); |
1853 | if (err) | |
1854 | goto out; | |
1855 | ||
4ff6abff | 1856 | mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); |
240936e1 AM |
1857 | if (!mod->holders_dir) { |
1858 | err = -ENOMEM; | |
270a6c4c | 1859 | goto out_unreg; |
240936e1 | 1860 | } |
270a6c4c | 1861 | |
1da177e4 LT |
1862 | err = module_param_sysfs_setup(mod, kparam, num_params); |
1863 | if (err) | |
270a6c4c | 1864 | goto out_unreg_holders; |
1da177e4 | 1865 | |
c988d2b2 MD |
1866 | err = module_add_modinfo_attrs(mod); |
1867 | if (err) | |
e17e0f51 | 1868 | goto out_unreg_param; |
c988d2b2 | 1869 | |
1ba5c08b CL |
1870 | err = add_usage_links(mod); |
1871 | if (err) | |
1872 | goto out_unreg_modinfo_attrs; | |
1873 | ||
8f6d0378 RR |
1874 | add_sect_attrs(mod, info); |
1875 | add_notes_attrs(mod, info); | |
80a3d1bb | 1876 | |
1da177e4 LT |
1877 | return 0; |
1878 | ||
1ba5c08b | 1879 | out_unreg_modinfo_attrs: |
bc6f2a75 | 1880 | module_remove_modinfo_attrs(mod, -1); |
e17e0f51 KS |
1881 | out_unreg_param: |
1882 | module_param_sysfs_remove(mod); | |
270a6c4c | 1883 | out_unreg_holders: |
78a2d906 | 1884 | kobject_put(mod->holders_dir); |
270a6c4c | 1885 | out_unreg: |
942e4431 | 1886 | mod_kobject_put(mod); |
80a3d1bb | 1887 | out: |
1da177e4 LT |
1888 | return err; |
1889 | } | |
34e4e2fe DL |
1890 | |
1891 | static void mod_sysfs_fini(struct module *mod) | |
1892 | { | |
8f6d0378 RR |
1893 | remove_notes_attrs(mod); |
1894 | remove_sect_attrs(mod); | |
942e4431 | 1895 | mod_kobject_put(mod); |
34e4e2fe DL |
1896 | } |
1897 | ||
cf2fde7b RR |
1898 | static void init_param_lock(struct module *mod) |
1899 | { | |
1900 | mutex_init(&mod->param_lock); | |
1901 | } | |
8f6d0378 | 1902 | #else /* !CONFIG_SYSFS */ |
34e4e2fe | 1903 | |
8f6d0378 RR |
1904 | static int mod_sysfs_setup(struct module *mod, |
1905 | const struct load_info *info, | |
6407ebb2 RR |
1906 | struct kernel_param *kparam, |
1907 | unsigned int num_params) | |
1908 | { | |
1909 | return 0; | |
1910 | } | |
1911 | ||
34e4e2fe DL |
1912 | static void mod_sysfs_fini(struct module *mod) |
1913 | { | |
1914 | } | |
1915 | ||
bc6f2a75 | 1916 | static void module_remove_modinfo_attrs(struct module *mod, int end) |
36b0360d RR |
1917 | { |
1918 | } | |
1919 | ||
80a3d1bb RR |
1920 | static void del_usage_links(struct module *mod) |
1921 | { | |
1922 | } | |
1923 | ||
cf2fde7b RR |
1924 | static void init_param_lock(struct module *mod) |
1925 | { | |
1926 | } | |
34e4e2fe | 1927 | #endif /* CONFIG_SYSFS */ |
1da177e4 | 1928 | |
36b0360d | 1929 | static void mod_sysfs_teardown(struct module *mod) |
1da177e4 | 1930 | { |
80a3d1bb | 1931 | del_usage_links(mod); |
bc6f2a75 | 1932 | module_remove_modinfo_attrs(mod, -1); |
1da177e4 | 1933 | module_param_sysfs_remove(mod); |
78a2d906 GKH |
1934 | kobject_put(mod->mkobj.drivers_dir); |
1935 | kobject_put(mod->holders_dir); | |
34e4e2fe | 1936 | mod_sysfs_fini(mod); |
1da177e4 LT |
1937 | } |
1938 | ||
84e1c6bb MC |
1939 | /* |
1940 | * LKM RO/NX protection: protect module's text/ro-data | |
1941 | * from modification and any data from execution. | |
85c898db RR |
1942 | * |
1943 | * General layout of module is: | |
444d13ff JY |
1944 | * [text] [read-only-data] [ro-after-init] [writable data] |
1945 | * text_size -----^ ^ ^ ^ | |
1946 | * ro_size ------------------------| | | | |
1947 | * ro_after_init_size -----------------------------| | | |
1948 | * size -----------------------------------------------------------| | |
85c898db RR |
1949 | * |
1950 | * These values are always page-aligned (as is base) | |
84e1c6bb | 1951 | */ |
db991af0 JY |
1952 | |
1953 | /* | |
1954 | * Since some arches are moving towards PAGE_KERNEL module allocations instead | |
1955 | * of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() outside of the | |
1956 | * CONFIG_STRICT_MODULE_RWX block below because they are needed regardless of | |
1957 | * whether we are strict. | |
1958 | */ | |
1959 | #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX | |
85c898db RR |
1960 | static void frob_text(const struct module_layout *layout, |
1961 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 1962 | { |
85c898db RR |
1963 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
1964 | BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1)); | |
1965 | set_memory((unsigned long)layout->base, | |
1966 | layout->text_size >> PAGE_SHIFT); | |
84e1c6bb | 1967 | } |
84e1c6bb | 1968 | |
db991af0 JY |
1969 | static void module_enable_x(const struct module *mod) |
1970 | { | |
1971 | frob_text(&mod->core_layout, set_memory_x); | |
1972 | frob_text(&mod->init_layout, set_memory_x); | |
1973 | } | |
1974 | #else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */ | |
1975 | static void module_enable_x(const struct module *mod) { } | |
1976 | #endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */ | |
1977 | ||
93651f80 | 1978 | #ifdef CONFIG_STRICT_MODULE_RWX |
85c898db RR |
1979 | static void frob_rodata(const struct module_layout *layout, |
1980 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 1981 | { |
85c898db RR |
1982 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
1983 | BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1)); | |
1984 | BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1)); | |
1985 | set_memory((unsigned long)layout->base + layout->text_size, | |
1986 | (layout->ro_size - layout->text_size) >> PAGE_SHIFT); | |
84e1c6bb MC |
1987 | } |
1988 | ||
444d13ff JY |
1989 | static void frob_ro_after_init(const struct module_layout *layout, |
1990 | int (*set_memory)(unsigned long start, int num_pages)) | |
1991 | { | |
1992 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); | |
1993 | BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1)); | |
1994 | BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1)); | |
1995 | set_memory((unsigned long)layout->base + layout->ro_size, | |
1996 | (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT); | |
1997 | } | |
1998 | ||
85c898db RR |
1999 | static void frob_writable_data(const struct module_layout *layout, |
2000 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 2001 | { |
85c898db | 2002 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
444d13ff | 2003 | BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1)); |
85c898db | 2004 | BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1)); |
444d13ff JY |
2005 | set_memory((unsigned long)layout->base + layout->ro_after_init_size, |
2006 | (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT); | |
84e1c6bb | 2007 | } |
84e1c6bb | 2008 | |
e6eff437 | 2009 | static void module_enable_ro(const struct module *mod, bool after_init) |
01526ed0 | 2010 | { |
39290b38 AT |
2011 | if (!rodata_enabled) |
2012 | return; | |
2013 | ||
1a7b7d92 RE |
2014 | set_vm_flush_reset_perms(mod->core_layout.base); |
2015 | set_vm_flush_reset_perms(mod->init_layout.base); | |
85c898db | 2016 | frob_text(&mod->core_layout, set_memory_ro); |
f2c65fb3 | 2017 | |
85c898db RR |
2018 | frob_rodata(&mod->core_layout, set_memory_ro); |
2019 | frob_text(&mod->init_layout, set_memory_ro); | |
2020 | frob_rodata(&mod->init_layout, set_memory_ro); | |
444d13ff JY |
2021 | |
2022 | if (after_init) | |
2023 | frob_ro_after_init(&mod->core_layout, set_memory_ro); | |
84e1c6bb MC |
2024 | } |
2025 | ||
85c898db | 2026 | static void module_enable_nx(const struct module *mod) |
01526ed0 | 2027 | { |
85c898db | 2028 | frob_rodata(&mod->core_layout, set_memory_nx); |
444d13ff | 2029 | frob_ro_after_init(&mod->core_layout, set_memory_nx); |
85c898db RR |
2030 | frob_writable_data(&mod->core_layout, set_memory_nx); |
2031 | frob_rodata(&mod->init_layout, set_memory_nx); | |
2032 | frob_writable_data(&mod->init_layout, set_memory_nx); | |
01526ed0 JG |
2033 | } |
2034 | ||
5c3a7db0 PZ |
2035 | static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, |
2036 | char *secstrings, struct module *mod) | |
2037 | { | |
2038 | const unsigned long shf_wx = SHF_WRITE|SHF_EXECINSTR; | |
2039 | int i; | |
2040 | ||
2041 | for (i = 0; i < hdr->e_shnum; i++) { | |
14721add QW |
2042 | if ((sechdrs[i].sh_flags & shf_wx) == shf_wx) { |
2043 | pr_err("%s: section %s (index %d) has invalid WRITE|EXEC flags\n", | |
2044 | mod->name, secstrings + sechdrs[i].sh_name, i); | |
5c3a7db0 | 2045 | return -ENOEXEC; |
14721add | 2046 | } |
5c3a7db0 PZ |
2047 | } |
2048 | ||
2049 | return 0; | |
2050 | } | |
2051 | ||
93651f80 | 2052 | #else /* !CONFIG_STRICT_MODULE_RWX */ |
85c898db | 2053 | static void module_enable_nx(const struct module *mod) { } |
e6eff437 | 2054 | static void module_enable_ro(const struct module *mod, bool after_init) {} |
5c3a7db0 PZ |
2055 | static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, |
2056 | char *secstrings, struct module *mod) | |
2eef1399 | 2057 | { |
5c3a7db0 | 2058 | return 0; |
2eef1399 | 2059 | } |
93651f80 | 2060 | #endif /* CONFIG_STRICT_MODULE_RWX */ |
84e1c6bb | 2061 | |
1ce15ef4 JY |
2062 | #ifdef CONFIG_LIVEPATCH |
2063 | /* | |
2064 | * Persist Elf information about a module. Copy the Elf header, | |
2065 | * section header table, section string table, and symtab section | |
2066 | * index from info to mod->klp_info. | |
2067 | */ | |
2068 | static int copy_module_elf(struct module *mod, struct load_info *info) | |
2069 | { | |
2070 | unsigned int size, symndx; | |
2071 | int ret; | |
2072 | ||
2073 | size = sizeof(*mod->klp_info); | |
2074 | mod->klp_info = kmalloc(size, GFP_KERNEL); | |
2075 | if (mod->klp_info == NULL) | |
2076 | return -ENOMEM; | |
2077 | ||
2078 | /* Elf header */ | |
2079 | size = sizeof(mod->klp_info->hdr); | |
2080 | memcpy(&mod->klp_info->hdr, info->hdr, size); | |
2081 | ||
2082 | /* Elf section header table */ | |
2083 | size = sizeof(*info->sechdrs) * info->hdr->e_shnum; | |
9be936f4 | 2084 | mod->klp_info->sechdrs = kmemdup(info->sechdrs, size, GFP_KERNEL); |
1ce15ef4 JY |
2085 | if (mod->klp_info->sechdrs == NULL) { |
2086 | ret = -ENOMEM; | |
2087 | goto free_info; | |
2088 | } | |
1ce15ef4 JY |
2089 | |
2090 | /* Elf section name string table */ | |
2091 | size = info->sechdrs[info->hdr->e_shstrndx].sh_size; | |
9be936f4 | 2092 | mod->klp_info->secstrings = kmemdup(info->secstrings, size, GFP_KERNEL); |
1ce15ef4 JY |
2093 | if (mod->klp_info->secstrings == NULL) { |
2094 | ret = -ENOMEM; | |
2095 | goto free_sechdrs; | |
2096 | } | |
1ce15ef4 JY |
2097 | |
2098 | /* Elf symbol section index */ | |
2099 | symndx = info->index.sym; | |
2100 | mod->klp_info->symndx = symndx; | |
2101 | ||
2102 | /* | |
2103 | * For livepatch modules, core_kallsyms.symtab is a complete | |
2104 | * copy of the original symbol table. Adjust sh_addr to point | |
2105 | * to core_kallsyms.symtab since the copy of the symtab in module | |
2106 | * init memory is freed at the end of do_init_module(). | |
2107 | */ | |
2108 | mod->klp_info->sechdrs[symndx].sh_addr = \ | |
2109 | (unsigned long) mod->core_kallsyms.symtab; | |
2110 | ||
2111 | return 0; | |
2112 | ||
2113 | free_sechdrs: | |
2114 | kfree(mod->klp_info->sechdrs); | |
2115 | free_info: | |
2116 | kfree(mod->klp_info); | |
2117 | return ret; | |
2118 | } | |
2119 | ||
2120 | static void free_module_elf(struct module *mod) | |
2121 | { | |
2122 | kfree(mod->klp_info->sechdrs); | |
2123 | kfree(mod->klp_info->secstrings); | |
2124 | kfree(mod->klp_info); | |
2125 | } | |
2126 | #else /* !CONFIG_LIVEPATCH */ | |
2127 | static int copy_module_elf(struct module *mod, struct load_info *info) | |
2128 | { | |
2129 | return 0; | |
2130 | } | |
2131 | ||
2132 | static void free_module_elf(struct module *mod) | |
2133 | { | |
2134 | } | |
2135 | #endif /* CONFIG_LIVEPATCH */ | |
2136 | ||
be1f221c | 2137 | void __weak module_memfree(void *module_region) |
74e08fcf | 2138 | { |
1a7b7d92 RE |
2139 | /* |
2140 | * This memory may be RO, and freeing RO memory in an interrupt is not | |
2141 | * supported by vmalloc. | |
2142 | */ | |
2143 | WARN_ON(in_interrupt()); | |
74e08fcf JB |
2144 | vfree(module_region); |
2145 | } | |
2146 | ||
2147 | void __weak module_arch_cleanup(struct module *mod) | |
2148 | { | |
2149 | } | |
2150 | ||
d453cded RR |
2151 | void __weak module_arch_freeing_init(struct module *mod) |
2152 | { | |
2153 | } | |
2154 | ||
cf68fffb ST |
2155 | static void cfi_cleanup(struct module *mod); |
2156 | ||
75676500 | 2157 | /* Free a module, remove from lists, etc. */ |
1da177e4 LT |
2158 | static void free_module(struct module *mod) |
2159 | { | |
7ead8b83 LZ |
2160 | trace_module_free(mod); |
2161 | ||
36b0360d | 2162 | mod_sysfs_teardown(mod); |
1da177e4 | 2163 | |
24b9f0d2 SS |
2164 | /* |
2165 | * We leave it in list to prevent duplicate loads, but make sure | |
2166 | * that noone uses it while it's being deconstructed. | |
2167 | */ | |
d3051b48 | 2168 | mutex_lock(&module_mutex); |
944a1fa0 | 2169 | mod->state = MODULE_STATE_UNFORMED; |
d3051b48 | 2170 | mutex_unlock(&module_mutex); |
944a1fa0 | 2171 | |
b82bab4b JB |
2172 | /* Remove dynamic debug info */ |
2173 | ddebug_remove_module(mod->name); | |
2174 | ||
1da177e4 LT |
2175 | /* Arch-specific cleanup. */ |
2176 | module_arch_cleanup(mod); | |
2177 | ||
2178 | /* Module unload stuff */ | |
2179 | module_unload_free(mod); | |
2180 | ||
e180a6b7 RR |
2181 | /* Free any allocated parameters. */ |
2182 | destroy_params(mod->kp, mod->num_kp); | |
2183 | ||
1ce15ef4 JY |
2184 | if (is_livepatch_module(mod)) |
2185 | free_module_elf(mod); | |
2186 | ||
944a1fa0 RR |
2187 | /* Now we can delete it from the lists */ |
2188 | mutex_lock(&module_mutex); | |
461e34ae MH |
2189 | /* Unlink carefully: kallsyms could be walking list. */ |
2190 | list_del_rcu(&mod->list); | |
93c2e105 | 2191 | mod_tree_remove(mod); |
0286b5ea | 2192 | /* Remove this module from bug list, this uses list_del_rcu */ |
461e34ae | 2193 | module_bug_cleanup(mod); |
0be964be | 2194 | /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */ |
cb2f5536 | 2195 | synchronize_rcu(); |
944a1fa0 RR |
2196 | mutex_unlock(&module_mutex); |
2197 | ||
cf68fffb ST |
2198 | /* Clean up CFI for the module. */ |
2199 | cfi_cleanup(mod); | |
2200 | ||
85c898db | 2201 | /* This may be empty, but that's OK */ |
d453cded | 2202 | module_arch_freeing_init(mod); |
7523e4dc | 2203 | module_memfree(mod->init_layout.base); |
1da177e4 | 2204 | kfree(mod->args); |
259354de | 2205 | percpu_modfree(mod); |
9f85a4bb | 2206 | |
35a9393c | 2207 | /* Free lock-classes; relies on the preceding sync_rcu(). */ |
7523e4dc | 2208 | lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size); |
fbb9ce95 | 2209 | |
1da177e4 | 2210 | /* Finally, free the core (containing the module structure) */ |
7523e4dc | 2211 | module_memfree(mod->core_layout.base); |
1da177e4 LT |
2212 | } |
2213 | ||
2214 | void *__symbol_get(const char *symbol) | |
2215 | { | |
0b96615c CH |
2216 | struct find_symbol_arg fsa = { |
2217 | .name = symbol, | |
2218 | .gplok = true, | |
2219 | .warn = true, | |
2220 | }; | |
1da177e4 | 2221 | |
24da1cbf | 2222 | preempt_disable(); |
0b96615c CH |
2223 | if (!find_symbol(&fsa) || strong_try_module_get(fsa.owner)) { |
2224 | preempt_enable(); | |
2225 | return NULL; | |
2226 | } | |
24da1cbf | 2227 | preempt_enable(); |
0b96615c | 2228 | return (void *)kernel_symbol_value(fsa.sym); |
1da177e4 LT |
2229 | } |
2230 | EXPORT_SYMBOL_GPL(__symbol_get); | |
2231 | ||
eea8b54d AN |
2232 | /* |
2233 | * Ensure that an exported symbol [global namespace] does not already exist | |
02a3e59a | 2234 | * in the kernel or in some other module's exported symbol table. |
be593f4c RR |
2235 | * |
2236 | * You must hold the module_mutex. | |
eea8b54d | 2237 | */ |
2d25bc55 | 2238 | static int verify_exported_symbols(struct module *mod) |
eea8b54d | 2239 | { |
b211104d | 2240 | unsigned int i; |
b211104d RR |
2241 | const struct kernel_symbol *s; |
2242 | struct { | |
2243 | const struct kernel_symbol *sym; | |
2244 | unsigned int num; | |
2245 | } arr[] = { | |
2246 | { mod->syms, mod->num_syms }, | |
2247 | { mod->gpl_syms, mod->num_gpl_syms }, | |
b211104d | 2248 | }; |
eea8b54d | 2249 | |
b211104d RR |
2250 | for (i = 0; i < ARRAY_SIZE(arr); i++) { |
2251 | for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) { | |
0b96615c CH |
2252 | struct find_symbol_arg fsa = { |
2253 | .name = kernel_symbol_name(s), | |
2254 | .gplok = true, | |
2255 | }; | |
2256 | if (find_symbol(&fsa)) { | |
bddb12b3 | 2257 | pr_err("%s: exports duplicate symbol %s" |
b211104d | 2258 | " (owned by %s)\n", |
7290d580 | 2259 | mod->name, kernel_symbol_name(s), |
0b96615c | 2260 | module_name(fsa.owner)); |
b211104d RR |
2261 | return -ENOEXEC; |
2262 | } | |
eea8b54d | 2263 | } |
b211104d RR |
2264 | } |
2265 | return 0; | |
eea8b54d AN |
2266 | } |
2267 | ||
ebfac7b7 FS |
2268 | static bool ignore_undef_symbol(Elf_Half emachine, const char *name) |
2269 | { | |
2270 | /* | |
2271 | * On x86, PIC code and Clang non-PIC code may have call foo@PLT. GNU as | |
2272 | * before 2.37 produces an unreferenced _GLOBAL_OFFSET_TABLE_ on x86-64. | |
2273 | * i386 has a similar problem but may not deserve a fix. | |
2274 | * | |
2275 | * If we ever have to ignore many symbols, consider refactoring the code to | |
2276 | * only warn if referenced by a relocation. | |
2277 | */ | |
2278 | if (emachine == EM_386 || emachine == EM_X86_64) | |
2279 | return !strcmp(name, "_GLOBAL_OFFSET_TABLE_"); | |
2280 | return false; | |
2281 | } | |
2282 | ||
9a4b9708 | 2283 | /* Change all symbols so that st_value encodes the pointer directly. */ |
49668688 RR |
2284 | static int simplify_symbols(struct module *mod, const struct load_info *info) |
2285 | { | |
2286 | Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; | |
2287 | Elf_Sym *sym = (void *)symsec->sh_addr; | |
1da177e4 | 2288 | unsigned long secbase; |
49668688 | 2289 | unsigned int i; |
1da177e4 | 2290 | int ret = 0; |
414fd31b | 2291 | const struct kernel_symbol *ksym; |
1da177e4 | 2292 | |
49668688 RR |
2293 | for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) { |
2294 | const char *name = info->strtab + sym[i].st_name; | |
2295 | ||
1da177e4 LT |
2296 | switch (sym[i].st_shndx) { |
2297 | case SHN_COMMON: | |
80375980 JM |
2298 | /* Ignore common symbols */ |
2299 | if (!strncmp(name, "__gnu_lto", 9)) | |
2300 | break; | |
2301 | ||
24b9f0d2 SS |
2302 | /* |
2303 | * We compiled with -fno-common. These are not | |
2304 | * supposed to happen. | |
2305 | */ | |
5e124169 | 2306 | pr_debug("Common symbol: %s\n", name); |
6da0b565 | 2307 | pr_warn("%s: please compile with -fno-common\n", |
1da177e4 LT |
2308 | mod->name); |
2309 | ret = -ENOEXEC; | |
2310 | break; | |
2311 | ||
2312 | case SHN_ABS: | |
2313 | /* Don't need to do anything */ | |
5e124169 | 2314 | pr_debug("Absolute symbol: 0x%08lx\n", |
1da177e4 LT |
2315 | (long)sym[i].st_value); |
2316 | break; | |
2317 | ||
1ce15ef4 JY |
2318 | case SHN_LIVEPATCH: |
2319 | /* Livepatch symbols are resolved by livepatch */ | |
2320 | break; | |
2321 | ||
1da177e4 | 2322 | case SHN_UNDEF: |
49668688 | 2323 | ksym = resolve_symbol_wait(mod, info, name); |
1da177e4 | 2324 | /* Ok if resolved. */ |
9bea7f23 | 2325 | if (ksym && !IS_ERR(ksym)) { |
7290d580 | 2326 | sym[i].st_value = kernel_symbol_value(ksym); |
1da177e4 | 2327 | break; |
414fd31b TA |
2328 | } |
2329 | ||
ebfac7b7 FS |
2330 | /* Ok if weak or ignored. */ |
2331 | if (!ksym && | |
2332 | (ELF_ST_BIND(sym[i].st_info) == STB_WEAK || | |
2333 | ignore_undef_symbol(info->hdr->e_machine, name))) | |
1da177e4 LT |
2334 | break; |
2335 | ||
9bea7f23 | 2336 | ret = PTR_ERR(ksym) ?: -ENOENT; |
62267e0e JD |
2337 | pr_warn("%s: Unknown symbol %s (err %d)\n", |
2338 | mod->name, name, ret); | |
1da177e4 LT |
2339 | break; |
2340 | ||
2341 | default: | |
2342 | /* Divert to percpu allocation if a percpu var. */ | |
49668688 | 2343 | if (sym[i].st_shndx == info->index.pcpu) |
259354de | 2344 | secbase = (unsigned long)mod_percpu(mod); |
1da177e4 | 2345 | else |
49668688 | 2346 | secbase = info->sechdrs[sym[i].st_shndx].sh_addr; |
1da177e4 LT |
2347 | sym[i].st_value += secbase; |
2348 | break; | |
2349 | } | |
2350 | } | |
2351 | ||
2352 | return ret; | |
2353 | } | |
2354 | ||
49668688 | 2355 | static int apply_relocations(struct module *mod, const struct load_info *info) |
22e268eb RR |
2356 | { |
2357 | unsigned int i; | |
2358 | int err = 0; | |
2359 | ||
2360 | /* Now do relocations. */ | |
49668688 RR |
2361 | for (i = 1; i < info->hdr->e_shnum; i++) { |
2362 | unsigned int infosec = info->sechdrs[i].sh_info; | |
22e268eb RR |
2363 | |
2364 | /* Not a valid relocation section? */ | |
49668688 | 2365 | if (infosec >= info->hdr->e_shnum) |
22e268eb RR |
2366 | continue; |
2367 | ||
2368 | /* Don't bother with non-allocated sections */ | |
49668688 | 2369 | if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC)) |
22e268eb RR |
2370 | continue; |
2371 | ||
1ce15ef4 | 2372 | if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH) |
7c8e2bdd JP |
2373 | err = klp_apply_section_relocs(mod, info->sechdrs, |
2374 | info->secstrings, | |
2375 | info->strtab, | |
2376 | info->index.sym, i, | |
2377 | NULL); | |
2378 | else if (info->sechdrs[i].sh_type == SHT_REL) | |
49668688 RR |
2379 | err = apply_relocate(info->sechdrs, info->strtab, |
2380 | info->index.sym, i, mod); | |
2381 | else if (info->sechdrs[i].sh_type == SHT_RELA) | |
2382 | err = apply_relocate_add(info->sechdrs, info->strtab, | |
2383 | info->index.sym, i, mod); | |
22e268eb RR |
2384 | if (err < 0) |
2385 | break; | |
2386 | } | |
2387 | return err; | |
2388 | } | |
2389 | ||
088af9a6 HD |
2390 | /* Additional bytes needed by arch in front of individual sections */ |
2391 | unsigned int __weak arch_mod_section_prepend(struct module *mod, | |
2392 | unsigned int section) | |
2393 | { | |
2394 | /* default implementation just returns zero */ | |
2395 | return 0; | |
2396 | } | |
2397 | ||
1da177e4 | 2398 | /* Update size with this section: return offset. */ |
088af9a6 HD |
2399 | static long get_offset(struct module *mod, unsigned int *size, |
2400 | Elf_Shdr *sechdr, unsigned int section) | |
1da177e4 LT |
2401 | { |
2402 | long ret; | |
2403 | ||
088af9a6 | 2404 | *size += arch_mod_section_prepend(mod, section); |
1da177e4 LT |
2405 | ret = ALIGN(*size, sechdr->sh_addralign ?: 1); |
2406 | *size = ret + sechdr->sh_size; | |
2407 | return ret; | |
2408 | } | |
2409 | ||
055f23b7 JY |
2410 | static bool module_init_layout_section(const char *sname) |
2411 | { | |
2412 | #ifndef CONFIG_MODULE_UNLOAD | |
2413 | if (module_exit_section(sname)) | |
2414 | return true; | |
2415 | #endif | |
2416 | return module_init_section(sname); | |
2417 | } | |
2418 | ||
24b9f0d2 SS |
2419 | /* |
2420 | * Lay out the SHF_ALLOC sections in a way not dissimilar to how ld | |
2421 | * might -- code, read-only data, read-write data, small data. Tally | |
2422 | * sizes, and place the offsets into sh_entsize fields: high bit means it | |
2423 | * belongs in init. | |
2424 | */ | |
49668688 | 2425 | static void layout_sections(struct module *mod, struct load_info *info) |
1da177e4 LT |
2426 | { |
2427 | static unsigned long const masks[][2] = { | |
24b9f0d2 SS |
2428 | /* |
2429 | * NOTE: all executable code must be the first section | |
1da177e4 | 2430 | * in this array; otherwise modify the text_size |
24b9f0d2 SS |
2431 | * finder in the two loops below |
2432 | */ | |
1da177e4 LT |
2433 | { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL }, |
2434 | { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL }, | |
444d13ff | 2435 | { SHF_RO_AFTER_INIT | SHF_ALLOC, ARCH_SHF_SMALL }, |
1da177e4 LT |
2436 | { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL }, |
2437 | { ARCH_SHF_SMALL | SHF_ALLOC, 0 } | |
2438 | }; | |
2439 | unsigned int m, i; | |
2440 | ||
49668688 RR |
2441 | for (i = 0; i < info->hdr->e_shnum; i++) |
2442 | info->sechdrs[i].sh_entsize = ~0UL; | |
1da177e4 | 2443 | |
5e124169 | 2444 | pr_debug("Core section allocation order:\n"); |
1da177e4 | 2445 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { |
49668688 RR |
2446 | for (i = 0; i < info->hdr->e_shnum; ++i) { |
2447 | Elf_Shdr *s = &info->sechdrs[i]; | |
2448 | const char *sname = info->secstrings + s->sh_name; | |
1da177e4 LT |
2449 | |
2450 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
2451 | || (s->sh_flags & masks[m][1]) | |
2452 | || s->sh_entsize != ~0UL | |
055f23b7 | 2453 | || module_init_layout_section(sname)) |
1da177e4 | 2454 | continue; |
7523e4dc | 2455 | s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i); |
5e124169 | 2456 | pr_debug("\t%s\n", sname); |
1da177e4 | 2457 | } |
84e1c6bb MC |
2458 | switch (m) { |
2459 | case 0: /* executable */ | |
7523e4dc RR |
2460 | mod->core_layout.size = debug_align(mod->core_layout.size); |
2461 | mod->core_layout.text_size = mod->core_layout.size; | |
84e1c6bb MC |
2462 | break; |
2463 | case 1: /* RO: text and ro-data */ | |
7523e4dc RR |
2464 | mod->core_layout.size = debug_align(mod->core_layout.size); |
2465 | mod->core_layout.ro_size = mod->core_layout.size; | |
84e1c6bb | 2466 | break; |
444d13ff JY |
2467 | case 2: /* RO after init */ |
2468 | mod->core_layout.size = debug_align(mod->core_layout.size); | |
2469 | mod->core_layout.ro_after_init_size = mod->core_layout.size; | |
2470 | break; | |
2471 | case 4: /* whole core */ | |
7523e4dc | 2472 | mod->core_layout.size = debug_align(mod->core_layout.size); |
84e1c6bb MC |
2473 | break; |
2474 | } | |
1da177e4 LT |
2475 | } |
2476 | ||
5e124169 | 2477 | pr_debug("Init section allocation order:\n"); |
1da177e4 | 2478 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { |
49668688 RR |
2479 | for (i = 0; i < info->hdr->e_shnum; ++i) { |
2480 | Elf_Shdr *s = &info->sechdrs[i]; | |
2481 | const char *sname = info->secstrings + s->sh_name; | |
1da177e4 LT |
2482 | |
2483 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
2484 | || (s->sh_flags & masks[m][1]) | |
2485 | || s->sh_entsize != ~0UL | |
055f23b7 | 2486 | || !module_init_layout_section(sname)) |
1da177e4 | 2487 | continue; |
7523e4dc | 2488 | s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i) |
1da177e4 | 2489 | | INIT_OFFSET_MASK); |
5e124169 | 2490 | pr_debug("\t%s\n", sname); |
1da177e4 | 2491 | } |
84e1c6bb MC |
2492 | switch (m) { |
2493 | case 0: /* executable */ | |
7523e4dc RR |
2494 | mod->init_layout.size = debug_align(mod->init_layout.size); |
2495 | mod->init_layout.text_size = mod->init_layout.size; | |
84e1c6bb MC |
2496 | break; |
2497 | case 1: /* RO: text and ro-data */ | |
7523e4dc RR |
2498 | mod->init_layout.size = debug_align(mod->init_layout.size); |
2499 | mod->init_layout.ro_size = mod->init_layout.size; | |
84e1c6bb | 2500 | break; |
444d13ff JY |
2501 | case 2: |
2502 | /* | |
2503 | * RO after init doesn't apply to init_layout (only | |
2504 | * core_layout), so it just takes the value of ro_size. | |
2505 | */ | |
2506 | mod->init_layout.ro_after_init_size = mod->init_layout.ro_size; | |
2507 | break; | |
2508 | case 4: /* whole init */ | |
7523e4dc | 2509 | mod->init_layout.size = debug_align(mod->init_layout.size); |
84e1c6bb MC |
2510 | break; |
2511 | } | |
1da177e4 LT |
2512 | } |
2513 | } | |
2514 | ||
1da177e4 LT |
2515 | static void set_license(struct module *mod, const char *license) |
2516 | { | |
2517 | if (!license) | |
2518 | license = "unspecified"; | |
2519 | ||
fa3ba2e8 | 2520 | if (!license_is_gpl_compatible(license)) { |
25ddbb18 | 2521 | if (!test_taint(TAINT_PROPRIETARY_MODULE)) |
bddb12b3 AM |
2522 | pr_warn("%s: module license '%s' taints kernel.\n", |
2523 | mod->name, license); | |
373d4d09 RR |
2524 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
2525 | LOCKDEP_NOW_UNRELIABLE); | |
1da177e4 LT |
2526 | } |
2527 | } | |
2528 | ||
2529 | /* Parse tag=value strings from .modinfo section */ | |
2530 | static char *next_string(char *string, unsigned long *secsize) | |
2531 | { | |
2532 | /* Skip non-zero chars */ | |
2533 | while (string[0]) { | |
2534 | string++; | |
2535 | if ((*secsize)-- <= 1) | |
2536 | return NULL; | |
2537 | } | |
2538 | ||
2539 | /* Skip any zero padding. */ | |
2540 | while (!string[0]) { | |
2541 | string++; | |
2542 | if ((*secsize)-- <= 1) | |
2543 | return NULL; | |
2544 | } | |
2545 | return string; | |
2546 | } | |
2547 | ||
c5e4a062 MM |
2548 | static char *get_next_modinfo(const struct load_info *info, const char *tag, |
2549 | char *prev) | |
1da177e4 LT |
2550 | { |
2551 | char *p; | |
2552 | unsigned int taglen = strlen(tag); | |
49668688 RR |
2553 | Elf_Shdr *infosec = &info->sechdrs[info->index.info]; |
2554 | unsigned long size = infosec->sh_size; | |
1da177e4 | 2555 | |
5fdc7db6 JY |
2556 | /* |
2557 | * get_modinfo() calls made before rewrite_section_headers() | |
2558 | * must use sh_offset, as sh_addr isn't set! | |
2559 | */ | |
c5e4a062 MM |
2560 | char *modinfo = (char *)info->hdr + infosec->sh_offset; |
2561 | ||
2562 | if (prev) { | |
2563 | size -= prev - modinfo; | |
2564 | modinfo = next_string(prev, &size); | |
2565 | } | |
2566 | ||
2567 | for (p = modinfo; p; p = next_string(p, &size)) { | |
1da177e4 LT |
2568 | if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') |
2569 | return p + taglen + 1; | |
2570 | } | |
2571 | return NULL; | |
2572 | } | |
2573 | ||
c5e4a062 MM |
2574 | static char *get_modinfo(const struct load_info *info, const char *tag) |
2575 | { | |
2576 | return get_next_modinfo(info, tag, NULL); | |
2577 | } | |
2578 | ||
49668688 | 2579 | static void setup_modinfo(struct module *mod, struct load_info *info) |
c988d2b2 MD |
2580 | { |
2581 | struct module_attribute *attr; | |
2582 | int i; | |
2583 | ||
2584 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
2585 | if (attr->setup) | |
49668688 | 2586 | attr->setup(mod, get_modinfo(info, attr->attr.name)); |
c988d2b2 MD |
2587 | } |
2588 | } | |
c988d2b2 | 2589 | |
a263f776 RR |
2590 | static void free_modinfo(struct module *mod) |
2591 | { | |
2592 | struct module_attribute *attr; | |
2593 | int i; | |
2594 | ||
2595 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
2596 | if (attr->free) | |
2597 | attr->free(mod); | |
2598 | } | |
2599 | } | |
2600 | ||
1da177e4 | 2601 | #ifdef CONFIG_KALLSYMS |
15bba37d | 2602 | |
2d25bc55 JY |
2603 | /* Lookup exported symbol in given range of kernel_symbols */ |
2604 | static const struct kernel_symbol *lookup_exported_symbol(const char *name, | |
2605 | const struct kernel_symbol *start, | |
2606 | const struct kernel_symbol *stop) | |
15bba37d | 2607 | { |
9d63487f AIB |
2608 | return bsearch(name, start, stop - start, |
2609 | sizeof(struct kernel_symbol), cmp_name); | |
15bba37d WC |
2610 | } |
2611 | ||
ca4787b7 TA |
2612 | static int is_exported(const char *name, unsigned long value, |
2613 | const struct module *mod) | |
1da177e4 | 2614 | { |
ca4787b7 TA |
2615 | const struct kernel_symbol *ks; |
2616 | if (!mod) | |
2d25bc55 | 2617 | ks = lookup_exported_symbol(name, __start___ksymtab, __stop___ksymtab); |
3fd6805f | 2618 | else |
2d25bc55 JY |
2619 | ks = lookup_exported_symbol(name, mod->syms, mod->syms + mod->num_syms); |
2620 | ||
7290d580 | 2621 | return ks != NULL && kernel_symbol_value(ks) == value; |
1da177e4 LT |
2622 | } |
2623 | ||
2624 | /* As per nm */ | |
eded41c1 | 2625 | static char elf_type(const Elf_Sym *sym, const struct load_info *info) |
1da177e4 | 2626 | { |
eded41c1 RR |
2627 | const Elf_Shdr *sechdrs = info->sechdrs; |
2628 | ||
1da177e4 LT |
2629 | if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { |
2630 | if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) | |
2631 | return 'v'; | |
2632 | else | |
2633 | return 'w'; | |
2634 | } | |
2635 | if (sym->st_shndx == SHN_UNDEF) | |
2636 | return 'U'; | |
e0224418 | 2637 | if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu) |
1da177e4 LT |
2638 | return 'a'; |
2639 | if (sym->st_shndx >= SHN_LORESERVE) | |
2640 | return '?'; | |
2641 | if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) | |
2642 | return 't'; | |
2643 | if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC | |
2644 | && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { | |
2645 | if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) | |
2646 | return 'r'; | |
2647 | else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
2648 | return 'g'; | |
2649 | else | |
2650 | return 'd'; | |
2651 | } | |
2652 | if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { | |
2653 | if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
2654 | return 's'; | |
2655 | else | |
2656 | return 'b'; | |
2657 | } | |
eded41c1 RR |
2658 | if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name, |
2659 | ".debug")) { | |
1da177e4 | 2660 | return 'n'; |
eded41c1 | 2661 | } |
1da177e4 LT |
2662 | return '?'; |
2663 | } | |
2664 | ||
4a496226 | 2665 | static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs, |
e0224418 | 2666 | unsigned int shnum, unsigned int pcpundx) |
4a496226 JB |
2667 | { |
2668 | const Elf_Shdr *sec; | |
2669 | ||
2670 | if (src->st_shndx == SHN_UNDEF | |
2671 | || src->st_shndx >= shnum | |
2672 | || !src->st_name) | |
2673 | return false; | |
2674 | ||
e0224418 MB |
2675 | #ifdef CONFIG_KALLSYMS_ALL |
2676 | if (src->st_shndx == pcpundx) | |
2677 | return true; | |
2678 | #endif | |
2679 | ||
4a496226 JB |
2680 | sec = sechdrs + src->st_shndx; |
2681 | if (!(sec->sh_flags & SHF_ALLOC) | |
2682 | #ifndef CONFIG_KALLSYMS_ALL | |
2683 | || !(sec->sh_flags & SHF_EXECINSTR) | |
2684 | #endif | |
2685 | || (sec->sh_entsize & INIT_OFFSET_MASK)) | |
2686 | return false; | |
2687 | ||
2688 | return true; | |
2689 | } | |
2690 | ||
48fd1188 KC |
2691 | /* |
2692 | * We only allocate and copy the strings needed by the parts of symtab | |
2693 | * we keep. This is simple, but has the effect of making multiple | |
2694 | * copies of duplicates. We could be more sophisticated, see | |
2695 | * linux-kernel thread starting with | |
2696 | * <73defb5e4bca04a6431392cc341112b1@localhost>. | |
2697 | */ | |
49668688 | 2698 | static void layout_symtab(struct module *mod, struct load_info *info) |
4a496226 | 2699 | { |
49668688 RR |
2700 | Elf_Shdr *symsect = info->sechdrs + info->index.sym; |
2701 | Elf_Shdr *strsect = info->sechdrs + info->index.str; | |
4a496226 | 2702 | const Elf_Sym *src; |
54523ec7 | 2703 | unsigned int i, nsrc, ndst, strtab_size = 0; |
4a496226 JB |
2704 | |
2705 | /* Put symbol section at end of init part of module. */ | |
2706 | symsect->sh_flags |= SHF_ALLOC; | |
7523e4dc | 2707 | symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect, |
49668688 | 2708 | info->index.sym) | INIT_OFFSET_MASK; |
5e124169 | 2709 | pr_debug("\t%s\n", info->secstrings + symsect->sh_name); |
4a496226 | 2710 | |
49668688 | 2711 | src = (void *)info->hdr + symsect->sh_offset; |
4a496226 | 2712 | nsrc = symsect->sh_size / sizeof(*src); |
70b1e916 | 2713 | |
48fd1188 | 2714 | /* Compute total space required for the core symbols' strtab. */ |
59ef28b1 | 2715 | for (ndst = i = 0; i < nsrc; i++) { |
1ce15ef4 | 2716 | if (i == 0 || is_livepatch_module(mod) || |
e0224418 MB |
2717 | is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, |
2718 | info->index.pcpu)) { | |
59ef28b1 | 2719 | strtab_size += strlen(&info->strtab[src[i].st_name])+1; |
48fd1188 | 2720 | ndst++; |
554bdfe5 | 2721 | } |
59ef28b1 | 2722 | } |
4a496226 JB |
2723 | |
2724 | /* Append room for core symbols at end of core part. */ | |
7523e4dc RR |
2725 | info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1); |
2726 | info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym); | |
2727 | mod->core_layout.size += strtab_size; | |
1c7651f4 EL |
2728 | info->core_typeoffs = mod->core_layout.size; |
2729 | mod->core_layout.size += ndst * sizeof(char); | |
7523e4dc | 2730 | mod->core_layout.size = debug_align(mod->core_layout.size); |
4a496226 | 2731 | |
554bdfe5 JB |
2732 | /* Put string table section at end of init part of module. */ |
2733 | strsect->sh_flags |= SHF_ALLOC; | |
7523e4dc | 2734 | strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect, |
49668688 | 2735 | info->index.str) | INIT_OFFSET_MASK; |
5e124169 | 2736 | pr_debug("\t%s\n", info->secstrings + strsect->sh_name); |
8244062e RR |
2737 | |
2738 | /* We'll tack temporary mod_kallsyms on the end. */ | |
2739 | mod->init_layout.size = ALIGN(mod->init_layout.size, | |
2740 | __alignof__(struct mod_kallsyms)); | |
2741 | info->mod_kallsyms_init_off = mod->init_layout.size; | |
2742 | mod->init_layout.size += sizeof(struct mod_kallsyms); | |
1c7651f4 EL |
2743 | info->init_typeoffs = mod->init_layout.size; |
2744 | mod->init_layout.size += nsrc * sizeof(char); | |
8244062e | 2745 | mod->init_layout.size = debug_align(mod->init_layout.size); |
4a496226 JB |
2746 | } |
2747 | ||
8244062e RR |
2748 | /* |
2749 | * We use the full symtab and strtab which layout_symtab arranged to | |
2750 | * be appended to the init section. Later we switch to the cut-down | |
2751 | * core-only ones. | |
2752 | */ | |
811d66a0 | 2753 | static void add_kallsyms(struct module *mod, const struct load_info *info) |
1da177e4 | 2754 | { |
4a496226 JB |
2755 | unsigned int i, ndst; |
2756 | const Elf_Sym *src; | |
2757 | Elf_Sym *dst; | |
554bdfe5 | 2758 | char *s; |
eded41c1 | 2759 | Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; |
1da177e4 | 2760 | |
8244062e RR |
2761 | /* Set up to point into init section. */ |
2762 | mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off; | |
2763 | ||
2764 | mod->kallsyms->symtab = (void *)symsec->sh_addr; | |
2765 | mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym); | |
511ca6ae | 2766 | /* Make sure we get permanent strtab: don't use info->strtab. */ |
8244062e | 2767 | mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr; |
1c7651f4 | 2768 | mod->kallsyms->typetab = mod->init_layout.base + info->init_typeoffs; |
1da177e4 | 2769 | |
1c7651f4 EL |
2770 | /* |
2771 | * Now populate the cut down core kallsyms for after init | |
2772 | * and set types up while we still have access to sections. | |
2773 | */ | |
8244062e RR |
2774 | mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs; |
2775 | mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs; | |
1c7651f4 | 2776 | mod->core_kallsyms.typetab = mod->core_layout.base + info->core_typeoffs; |
8244062e RR |
2777 | src = mod->kallsyms->symtab; |
2778 | for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) { | |
1c7651f4 | 2779 | mod->kallsyms->typetab[i] = elf_type(src + i, info); |
1ce15ef4 | 2780 | if (i == 0 || is_livepatch_module(mod) || |
e0224418 MB |
2781 | is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, |
2782 | info->index.pcpu)) { | |
1c7651f4 EL |
2783 | mod->core_kallsyms.typetab[ndst] = |
2784 | mod->kallsyms->typetab[i]; | |
59ef28b1 | 2785 | dst[ndst] = src[i]; |
8244062e RR |
2786 | dst[ndst++].st_name = s - mod->core_kallsyms.strtab; |
2787 | s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name], | |
59ef28b1 RR |
2788 | KSYM_NAME_LEN) + 1; |
2789 | } | |
4a496226 | 2790 | } |
8244062e | 2791 | mod->core_kallsyms.num_symtab = ndst; |
1da177e4 LT |
2792 | } |
2793 | #else | |
49668688 | 2794 | static inline void layout_symtab(struct module *mod, struct load_info *info) |
4a496226 JB |
2795 | { |
2796 | } | |
3ae91c21 | 2797 | |
abbce906 | 2798 | static void add_kallsyms(struct module *mod, const struct load_info *info) |
1da177e4 LT |
2799 | { |
2800 | } | |
2801 | #endif /* CONFIG_KALLSYMS */ | |
2802 | ||
9294523e SB |
2803 | #if IS_ENABLED(CONFIG_KALLSYMS) && IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) |
2804 | static void init_build_id(struct module *mod, const struct load_info *info) | |
2805 | { | |
2806 | const Elf_Shdr *sechdr; | |
2807 | unsigned int i; | |
2808 | ||
2809 | for (i = 0; i < info->hdr->e_shnum; i++) { | |
2810 | sechdr = &info->sechdrs[i]; | |
2811 | if (!sect_empty(sechdr) && sechdr->sh_type == SHT_NOTE && | |
2812 | !build_id_parse_buf((void *)sechdr->sh_addr, mod->build_id, | |
2813 | sechdr->sh_size)) | |
2814 | break; | |
2815 | } | |
2816 | } | |
2817 | #else | |
2818 | static void init_build_id(struct module *mod, const struct load_info *info) | |
2819 | { | |
2820 | } | |
2821 | #endif | |
2822 | ||
52796312 | 2823 | static void dynamic_debug_setup(struct module *mod, struct _ddebug *debug, unsigned int num) |
346e15be | 2824 | { |
811d66a0 RR |
2825 | if (!debug) |
2826 | return; | |
513770f5 | 2827 | ddebug_add_module(debug, num, mod->name); |
5e458cc0 | 2828 | } |
346e15be | 2829 | |
52796312 | 2830 | static void dynamic_debug_remove(struct module *mod, struct _ddebug *debug) |
ff49d74a YS |
2831 | { |
2832 | if (debug) | |
52796312 | 2833 | ddebug_remove_module(mod->name); |
ff49d74a YS |
2834 | } |
2835 | ||
74e08fcf JB |
2836 | void * __weak module_alloc(unsigned long size) |
2837 | { | |
7a0e27b2 CH |
2838 | return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END, |
2839 | GFP_KERNEL, PAGE_KERNEL_EXEC, VM_FLUSH_RESET_PERMS, | |
a3a66c38 | 2840 | NUMA_NO_NODE, __builtin_return_address(0)); |
74e08fcf JB |
2841 | } |
2842 | ||
23189766 VW |
2843 | bool __weak module_init_section(const char *name) |
2844 | { | |
2845 | return strstarts(name, ".init"); | |
2846 | } | |
2847 | ||
38b37d63 MS |
2848 | bool __weak module_exit_section(const char *name) |
2849 | { | |
2850 | return strstarts(name, ".exit"); | |
2851 | } | |
2852 | ||
4f2294b6 | 2853 | #ifdef CONFIG_DEBUG_KMEMLEAK |
49668688 RR |
2854 | static void kmemleak_load_module(const struct module *mod, |
2855 | const struct load_info *info) | |
4f2294b6 CM |
2856 | { |
2857 | unsigned int i; | |
2858 | ||
2859 | /* only scan the sections containing data */ | |
c017b4be | 2860 | kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL); |
4f2294b6 | 2861 | |
49668688 | 2862 | for (i = 1; i < info->hdr->e_shnum; i++) { |
06c9494c SR |
2863 | /* Scan all writable sections that's not executable */ |
2864 | if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) || | |
2865 | !(info->sechdrs[i].sh_flags & SHF_WRITE) || | |
2866 | (info->sechdrs[i].sh_flags & SHF_EXECINSTR)) | |
4f2294b6 CM |
2867 | continue; |
2868 | ||
49668688 RR |
2869 | kmemleak_scan_area((void *)info->sechdrs[i].sh_addr, |
2870 | info->sechdrs[i].sh_size, GFP_KERNEL); | |
4f2294b6 CM |
2871 | } |
2872 | } | |
2873 | #else | |
49668688 RR |
2874 | static inline void kmemleak_load_module(const struct module *mod, |
2875 | const struct load_info *info) | |
4f2294b6 CM |
2876 | { |
2877 | } | |
2878 | #endif | |
2879 | ||
106a4ee2 | 2880 | #ifdef CONFIG_MODULE_SIG |
bca014ca | 2881 | static int module_sig_check(struct load_info *info, int flags) |
106a4ee2 | 2882 | { |
49fcf732 | 2883 | int err = -ENODATA; |
34e1169d | 2884 | const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; |
49fcf732 | 2885 | const char *reason; |
34e1169d | 2886 | const void *mod = info->hdr; |
caabe240 | 2887 | |
bca014ca BH |
2888 | /* |
2889 | * Require flags == 0, as a module with version information | |
2890 | * removed is no longer the module that was signed | |
2891 | */ | |
2892 | if (flags == 0 && | |
2893 | info->len > markerlen && | |
34e1169d | 2894 | memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) { |
caabe240 | 2895 | /* We truncate the module to discard the signature */ |
34e1169d | 2896 | info->len -= markerlen; |
f314dfea | 2897 | err = mod_verify_sig(mod, info); |
076aa52e SS |
2898 | if (!err) { |
2899 | info->sig_ok = true; | |
2900 | return 0; | |
2901 | } | |
106a4ee2 RR |
2902 | } |
2903 | ||
076aa52e SS |
2904 | /* |
2905 | * We don't permit modules to be loaded into the trusted kernels | |
2906 | * without a valid signature on them, but if we're not enforcing, | |
2907 | * certain errors are non-fatal. | |
2908 | */ | |
49fcf732 | 2909 | switch (err) { |
49fcf732 | 2910 | case -ENODATA: |
705e9195 | 2911 | reason = "unsigned module"; |
10ccd1ab | 2912 | break; |
49fcf732 | 2913 | case -ENOPKG: |
705e9195 | 2914 | reason = "module with unsupported crypto"; |
10ccd1ab | 2915 | break; |
49fcf732 | 2916 | case -ENOKEY: |
705e9195 | 2917 | reason = "module with unavailable key"; |
10ccd1ab | 2918 | break; |
49fcf732 | 2919 | |
49fcf732 | 2920 | default: |
076aa52e SS |
2921 | /* |
2922 | * All other errors are fatal, including lack of memory, | |
2923 | * unparseable signatures, and signature check failures -- | |
2924 | * even if signatures aren't required. | |
2925 | */ | |
49fcf732 DH |
2926 | return err; |
2927 | } | |
10ccd1ab SS |
2928 | |
2929 | if (is_module_sig_enforced()) { | |
ec2a2959 | 2930 | pr_notice("Loading of %s is rejected\n", reason); |
10ccd1ab SS |
2931 | return -EKEYREJECTED; |
2932 | } | |
2933 | ||
2934 | return security_locked_down(LOCKDOWN_MODULE_SIGNATURE); | |
106a4ee2 RR |
2935 | } |
2936 | #else /* !CONFIG_MODULE_SIG */ | |
bca014ca | 2937 | static int module_sig_check(struct load_info *info, int flags) |
106a4ee2 RR |
2938 | { |
2939 | return 0; | |
2940 | } | |
2941 | #endif /* !CONFIG_MODULE_SIG */ | |
2942 | ||
ec2a2959 | 2943 | static int validate_section_offset(struct load_info *info, Elf_Shdr *shdr) |
40dd2560 | 2944 | { |
ec2a2959 FL |
2945 | unsigned long secend; |
2946 | ||
2947 | /* | |
2948 | * Check for both overflow and offset/size being | |
2949 | * too large. | |
2950 | */ | |
2951 | secend = shdr->sh_offset + shdr->sh_size; | |
2952 | if (secend < shdr->sh_offset || secend > info->len) | |
2953 | return -ENOEXEC; | |
2954 | ||
2955 | return 0; | |
2956 | } | |
2957 | ||
2958 | /* | |
2959 | * Sanity checks against invalid binaries, wrong arch, weird elf version. | |
2960 | * | |
2961 | * Also do basic validity checks against section offsets and sizes, the | |
2962 | * section name string table, and the indices used for it (sh_name). | |
2963 | */ | |
2964 | static int elf_validity_check(struct load_info *info) | |
2965 | { | |
2966 | unsigned int i; | |
2967 | Elf_Shdr *shdr, *strhdr; | |
2968 | int err; | |
2969 | ||
34e1169d KC |
2970 | if (info->len < sizeof(*(info->hdr))) |
2971 | return -ENOEXEC; | |
2972 | ||
2973 | if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0 | |
2974 | || info->hdr->e_type != ET_REL | |
2975 | || !elf_check_arch(info->hdr) | |
2976 | || info->hdr->e_shentsize != sizeof(Elf_Shdr)) | |
2977 | return -ENOEXEC; | |
2978 | ||
ec2a2959 FL |
2979 | /* |
2980 | * e_shnum is 16 bits, and sizeof(Elf_Shdr) is | |
2981 | * known and small. So e_shnum * sizeof(Elf_Shdr) | |
2982 | * will not overflow unsigned long on any platform. | |
2983 | */ | |
34e1169d KC |
2984 | if (info->hdr->e_shoff >= info->len |
2985 | || (info->hdr->e_shnum * sizeof(Elf_Shdr) > | |
2986 | info->len - info->hdr->e_shoff)) | |
2987 | return -ENOEXEC; | |
40dd2560 | 2988 | |
ec2a2959 FL |
2989 | info->sechdrs = (void *)info->hdr + info->hdr->e_shoff; |
2990 | ||
2991 | /* | |
2992 | * Verify if the section name table index is valid. | |
2993 | */ | |
2994 | if (info->hdr->e_shstrndx == SHN_UNDEF | |
2995 | || info->hdr->e_shstrndx >= info->hdr->e_shnum) | |
2996 | return -ENOEXEC; | |
2997 | ||
2998 | strhdr = &info->sechdrs[info->hdr->e_shstrndx]; | |
2999 | err = validate_section_offset(info, strhdr); | |
3000 | if (err < 0) | |
3001 | return err; | |
3002 | ||
3003 | /* | |
3004 | * The section name table must be NUL-terminated, as required | |
3005 | * by the spec. This makes strcmp and pr_* calls that access | |
3006 | * strings in the section safe. | |
3007 | */ | |
3008 | info->secstrings = (void *)info->hdr + strhdr->sh_offset; | |
3009 | if (info->secstrings[strhdr->sh_size - 1] != '\0') | |
3010 | return -ENOEXEC; | |
3011 | ||
3012 | /* | |
3013 | * The code assumes that section 0 has a length of zero and | |
3014 | * an addr of zero, so check for it. | |
3015 | */ | |
3016 | if (info->sechdrs[0].sh_type != SHT_NULL | |
3017 | || info->sechdrs[0].sh_size != 0 | |
3018 | || info->sechdrs[0].sh_addr != 0) | |
3019 | return -ENOEXEC; | |
3020 | ||
3021 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
3022 | shdr = &info->sechdrs[i]; | |
3023 | switch (shdr->sh_type) { | |
3024 | case SHT_NULL: | |
3025 | case SHT_NOBITS: | |
3026 | continue; | |
3027 | case SHT_SYMTAB: | |
3028 | if (shdr->sh_link == SHN_UNDEF | |
3029 | || shdr->sh_link >= info->hdr->e_shnum) | |
3030 | return -ENOEXEC; | |
3031 | fallthrough; | |
3032 | default: | |
3033 | err = validate_section_offset(info, shdr); | |
3034 | if (err < 0) { | |
3035 | pr_err("Invalid ELF section in module (section %u type %u)\n", | |
3036 | i, shdr->sh_type); | |
3037 | return err; | |
3038 | } | |
3039 | ||
3040 | if (shdr->sh_flags & SHF_ALLOC) { | |
3041 | if (shdr->sh_name >= strhdr->sh_size) { | |
3042 | pr_err("Invalid ELF section name in module (section %u type %u)\n", | |
3043 | i, shdr->sh_type); | |
3044 | return -ENOEXEC; | |
3045 | } | |
3046 | } | |
3047 | break; | |
3048 | } | |
3049 | } | |
3050 | ||
34e1169d KC |
3051 | return 0; |
3052 | } | |
3053 | ||
3afe9f84 LT |
3054 | #define COPY_CHUNK_SIZE (16*PAGE_SIZE) |
3055 | ||
3056 | static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len) | |
3057 | { | |
3058 | do { | |
3059 | unsigned long n = min(len, COPY_CHUNK_SIZE); | |
3060 | ||
3061 | if (copy_from_user(dst, usrc, n) != 0) | |
3062 | return -EFAULT; | |
3063 | cond_resched(); | |
3064 | dst += n; | |
3065 | usrc += n; | |
3066 | len -= n; | |
3067 | } while (len); | |
3068 | return 0; | |
3069 | } | |
3070 | ||
1ce15ef4 | 3071 | #ifdef CONFIG_LIVEPATCH |
2992ef29 | 3072 | static int check_modinfo_livepatch(struct module *mod, struct load_info *info) |
1ce15ef4 | 3073 | { |
2992ef29 JP |
3074 | if (get_modinfo(info, "livepatch")) { |
3075 | mod->klp = true; | |
3076 | add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK); | |
7598d167 JL |
3077 | pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n", |
3078 | mod->name); | |
2992ef29 | 3079 | } |
1ce15ef4 JY |
3080 | |
3081 | return 0; | |
3082 | } | |
3083 | #else /* !CONFIG_LIVEPATCH */ | |
2992ef29 | 3084 | static int check_modinfo_livepatch(struct module *mod, struct load_info *info) |
1ce15ef4 JY |
3085 | { |
3086 | if (get_modinfo(info, "livepatch")) { | |
3087 | pr_err("%s: module is marked as livepatch module, but livepatch support is disabled", | |
3088 | mod->name); | |
3089 | return -ENOEXEC; | |
3090 | } | |
3091 | ||
3092 | return 0; | |
3093 | } | |
3094 | #endif /* CONFIG_LIVEPATCH */ | |
3095 | ||
caf7501a AK |
3096 | static void check_modinfo_retpoline(struct module *mod, struct load_info *info) |
3097 | { | |
3098 | if (retpoline_module_ok(get_modinfo(info, "retpoline"))) | |
3099 | return; | |
3100 | ||
3101 | pr_warn("%s: loading module not compiled with retpoline compiler.\n", | |
3102 | mod->name); | |
3103 | } | |
3104 | ||
34e1169d KC |
3105 | /* Sets info->hdr and info->len. */ |
3106 | static int copy_module_from_user(const void __user *umod, unsigned long len, | |
3107 | struct load_info *info) | |
40dd2560 RR |
3108 | { |
3109 | int err; | |
40dd2560 | 3110 | |
34e1169d KC |
3111 | info->len = len; |
3112 | if (info->len < sizeof(*(info->hdr))) | |
40dd2560 RR |
3113 | return -ENOEXEC; |
3114 | ||
38f90173 | 3115 | err = security_kernel_load_data(LOADING_MODULE, true); |
2e72d51b KC |
3116 | if (err) |
3117 | return err; | |
3118 | ||
40dd2560 | 3119 | /* Suck in entire file: we'll want most of it. */ |
88dca4ca | 3120 | info->hdr = __vmalloc(info->len, GFP_KERNEL | __GFP_NOWARN); |
34e1169d | 3121 | if (!info->hdr) |
40dd2560 RR |
3122 | return -ENOMEM; |
3123 | ||
3afe9f84 | 3124 | if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) { |
38f90173 KC |
3125 | err = -EFAULT; |
3126 | goto out; | |
40dd2560 RR |
3127 | } |
3128 | ||
38f90173 KC |
3129 | err = security_kernel_post_load_data((char *)info->hdr, info->len, |
3130 | LOADING_MODULE, "init_module"); | |
3131 | out: | |
3132 | if (err) | |
3133 | vfree(info->hdr); | |
3134 | ||
3135 | return err; | |
34e1169d KC |
3136 | } |
3137 | ||
d913188c RR |
3138 | static void free_copy(struct load_info *info) |
3139 | { | |
d913188c RR |
3140 | vfree(info->hdr); |
3141 | } | |
3142 | ||
2f3238ae | 3143 | static int rewrite_section_headers(struct load_info *info, int flags) |
8b5f61a7 RR |
3144 | { |
3145 | unsigned int i; | |
3146 | ||
3147 | /* This should always be true, but let's be sure. */ | |
3148 | info->sechdrs[0].sh_addr = 0; | |
3149 | ||
3150 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
3151 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
8b5f61a7 | 3152 | |
24b9f0d2 SS |
3153 | /* |
3154 | * Mark all sections sh_addr with their address in the | |
3155 | * temporary image. | |
3156 | */ | |
8b5f61a7 RR |
3157 | shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset; |
3158 | ||
8b5f61a7 | 3159 | } |
d6df72a0 RR |
3160 | |
3161 | /* Track but don't keep modinfo and version sections. */ | |
3e2e857f | 3162 | info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC; |
d6df72a0 | 3163 | info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC; |
3e2e857f | 3164 | |
8b5f61a7 RR |
3165 | return 0; |
3166 | } | |
3167 | ||
3264d3f9 LT |
3168 | /* |
3169 | * Set up our basic convenience variables (pointers to section headers, | |
3170 | * search for module section index etc), and do some basic section | |
3171 | * verification. | |
3172 | * | |
81a0abd9 JY |
3173 | * Set info->mod to the temporary copy of the module in info->hdr. The final one |
3174 | * will be allocated in move_module(). | |
3264d3f9 | 3175 | */ |
81a0abd9 | 3176 | static int setup_load_info(struct load_info *info, int flags) |
3264d3f9 LT |
3177 | { |
3178 | unsigned int i; | |
3264d3f9 | 3179 | |
5fdc7db6 JY |
3180 | /* Try to find a name early so we can log errors with a module name */ |
3181 | info->index.info = find_sec(info, ".modinfo"); | |
708e0ada | 3182 | if (info->index.info) |
5fdc7db6 | 3183 | info->name = get_modinfo(info, "name"); |
3264d3f9 | 3184 | |
8b5f61a7 RR |
3185 | /* Find internal symbols and strings. */ |
3186 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
3264d3f9 LT |
3187 | if (info->sechdrs[i].sh_type == SHT_SYMTAB) { |
3188 | info->index.sym = i; | |
3189 | info->index.str = info->sechdrs[i].sh_link; | |
8b5f61a7 RR |
3190 | info->strtab = (char *)info->hdr |
3191 | + info->sechdrs[info->index.str].sh_offset; | |
3192 | break; | |
3264d3f9 | 3193 | } |
3264d3f9 LT |
3194 | } |
3195 | ||
5fdc7db6 | 3196 | if (info->index.sym == 0) { |
708e0ada JY |
3197 | pr_warn("%s: module has no symbols (stripped?)\n", |
3198 | info->name ?: "(missing .modinfo section or name field)"); | |
5fdc7db6 JY |
3199 | return -ENOEXEC; |
3200 | } | |
3201 | ||
49668688 | 3202 | info->index.mod = find_sec(info, ".gnu.linkonce.this_module"); |
3264d3f9 | 3203 | if (!info->index.mod) { |
3e2e857f | 3204 | pr_warn("%s: No module found in object\n", |
708e0ada | 3205 | info->name ?: "(missing .modinfo section or name field)"); |
81a0abd9 | 3206 | return -ENOEXEC; |
3264d3f9 LT |
3207 | } |
3208 | /* This is temporary: point mod into copy of data. */ | |
5fdc7db6 | 3209 | info->mod = (void *)info->hdr + info->sechdrs[info->index.mod].sh_offset; |
3264d3f9 | 3210 | |
3e2e857f | 3211 | /* |
5fdc7db6 | 3212 | * If we didn't load the .modinfo 'name' field earlier, fall back to |
3e2e857f KC |
3213 | * on-disk struct mod 'name' field. |
3214 | */ | |
3215 | if (!info->name) | |
81a0abd9 | 3216 | info->name = info->mod->name; |
3e2e857f | 3217 | |
5fdc7db6 JY |
3218 | if (flags & MODULE_INIT_IGNORE_MODVERSIONS) |
3219 | info->index.vers = 0; /* Pretend no __versions section! */ | |
3220 | else | |
3221 | info->index.vers = find_sec(info, "__versions"); | |
3264d3f9 | 3222 | |
49668688 | 3223 | info->index.pcpu = find_pcpusec(info); |
3264d3f9 | 3224 | |
81a0abd9 | 3225 | return 0; |
3264d3f9 LT |
3226 | } |
3227 | ||
2f3238ae | 3228 | static int check_modinfo(struct module *mod, struct load_info *info, int flags) |
40dd2560 | 3229 | { |
49668688 | 3230 | const char *modmagic = get_modinfo(info, "vermagic"); |
40dd2560 RR |
3231 | int err; |
3232 | ||
2f3238ae RR |
3233 | if (flags & MODULE_INIT_IGNORE_VERMAGIC) |
3234 | modmagic = NULL; | |
3235 | ||
40dd2560 RR |
3236 | /* This is allowed: modprobe --force will invalidate it. */ |
3237 | if (!modmagic) { | |
3238 | err = try_to_force_load(mod, "bad vermagic"); | |
3239 | if (err) | |
3240 | return err; | |
49668688 | 3241 | } else if (!same_magic(modmagic, vermagic, info->index.vers)) { |
bddb12b3 | 3242 | pr_err("%s: version magic '%s' should be '%s'\n", |
3e2e857f | 3243 | info->name, modmagic, vermagic); |
40dd2560 RR |
3244 | return -ENOEXEC; |
3245 | } | |
3246 | ||
3205c36c LP |
3247 | if (!get_modinfo(info, "intree")) { |
3248 | if (!test_taint(TAINT_OOT_MODULE)) | |
3249 | pr_warn("%s: loading out-of-tree module taints kernel.\n", | |
3250 | mod->name); | |
373d4d09 | 3251 | add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK); |
3205c36c | 3252 | } |
2449b8ba | 3253 | |
caf7501a AK |
3254 | check_modinfo_retpoline(mod, info); |
3255 | ||
49668688 | 3256 | if (get_modinfo(info, "staging")) { |
373d4d09 | 3257 | add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK); |
bddb12b3 AM |
3258 | pr_warn("%s: module is from the staging directory, the quality " |
3259 | "is unknown, you have been warned.\n", mod->name); | |
40dd2560 | 3260 | } |
22e268eb | 3261 | |
2992ef29 | 3262 | err = check_modinfo_livepatch(mod, info); |
1ce15ef4 JY |
3263 | if (err) |
3264 | return err; | |
3265 | ||
22e268eb | 3266 | /* Set up license info based on the info section */ |
49668688 | 3267 | set_license(mod, get_modinfo(info, "license")); |
22e268eb | 3268 | |
40dd2560 RR |
3269 | return 0; |
3270 | } | |
3271 | ||
eb3057df | 3272 | static int find_module_sections(struct module *mod, struct load_info *info) |
f91a13bb | 3273 | { |
49668688 | 3274 | mod->kp = section_objs(info, "__param", |
f91a13bb | 3275 | sizeof(*mod->kp), &mod->num_kp); |
49668688 | 3276 | mod->syms = section_objs(info, "__ksymtab", |
f91a13bb | 3277 | sizeof(*mod->syms), &mod->num_syms); |
49668688 RR |
3278 | mod->crcs = section_addr(info, "__kcrctab"); |
3279 | mod->gpl_syms = section_objs(info, "__ksymtab_gpl", | |
f91a13bb LT |
3280 | sizeof(*mod->gpl_syms), |
3281 | &mod->num_gpl_syms); | |
49668688 | 3282 | mod->gpl_crcs = section_addr(info, "__kcrctab_gpl"); |
f91a13bb | 3283 | |
f91a13bb | 3284 | #ifdef CONFIG_CONSTRUCTORS |
49668688 | 3285 | mod->ctors = section_objs(info, ".ctors", |
f91a13bb | 3286 | sizeof(*mod->ctors), &mod->num_ctors); |
eb3057df FH |
3287 | if (!mod->ctors) |
3288 | mod->ctors = section_objs(info, ".init_array", | |
3289 | sizeof(*mod->ctors), &mod->num_ctors); | |
3290 | else if (find_sec(info, ".init_array")) { | |
3291 | /* | |
3292 | * This shouldn't happen with same compiler and binutils | |
3293 | * building all parts of the module. | |
3294 | */ | |
6da0b565 | 3295 | pr_warn("%s: has both .ctors and .init_array.\n", |
eb3057df FH |
3296 | mod->name); |
3297 | return -EINVAL; | |
3298 | } | |
f91a13bb LT |
3299 | #endif |
3300 | ||
66e9b071 TG |
3301 | mod->noinstr_text_start = section_objs(info, ".noinstr.text", 1, |
3302 | &mod->noinstr_text_size); | |
3303 | ||
f91a13bb | 3304 | #ifdef CONFIG_TRACEPOINTS |
65498646 MD |
3305 | mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs", |
3306 | sizeof(*mod->tracepoints_ptrs), | |
3307 | &mod->num_tracepoints); | |
f91a13bb | 3308 | #endif |
fe15b50c PM |
3309 | #ifdef CONFIG_TREE_SRCU |
3310 | mod->srcu_struct_ptrs = section_objs(info, "___srcu_struct_ptrs", | |
3311 | sizeof(*mod->srcu_struct_ptrs), | |
3312 | &mod->num_srcu_structs); | |
3313 | #endif | |
a38d1107 MM |
3314 | #ifdef CONFIG_BPF_EVENTS |
3315 | mod->bpf_raw_events = section_objs(info, "__bpf_raw_tp_map", | |
3316 | sizeof(*mod->bpf_raw_events), | |
3317 | &mod->num_bpf_raw_events); | |
3318 | #endif | |
36e68442 AN |
3319 | #ifdef CONFIG_DEBUG_INFO_BTF_MODULES |
3320 | mod->btf_data = any_section_objs(info, ".BTF", 1, &mod->btf_data_size); | |
3321 | #endif | |
e9666d10 | 3322 | #ifdef CONFIG_JUMP_LABEL |
bf5438fc JB |
3323 | mod->jump_entries = section_objs(info, "__jump_table", |
3324 | sizeof(*mod->jump_entries), | |
3325 | &mod->num_jump_entries); | |
3326 | #endif | |
f91a13bb | 3327 | #ifdef CONFIG_EVENT_TRACING |
49668688 | 3328 | mod->trace_events = section_objs(info, "_ftrace_events", |
f91a13bb LT |
3329 | sizeof(*mod->trace_events), |
3330 | &mod->num_trace_events); | |
99be647c JL |
3331 | mod->trace_evals = section_objs(info, "_ftrace_eval_map", |
3332 | sizeof(*mod->trace_evals), | |
3333 | &mod->num_trace_evals); | |
f91a13bb | 3334 | #endif |
13b9b6e7 SR |
3335 | #ifdef CONFIG_TRACING |
3336 | mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt", | |
3337 | sizeof(*mod->trace_bprintk_fmt_start), | |
3338 | &mod->num_trace_bprintk_fmt); | |
13b9b6e7 | 3339 | #endif |
f91a13bb LT |
3340 | #ifdef CONFIG_FTRACE_MCOUNT_RECORD |
3341 | /* sechdrs[0].sh_size is always zero */ | |
a1326b17 | 3342 | mod->ftrace_callsites = section_objs(info, FTRACE_CALLSITE_SECTION, |
f91a13bb LT |
3343 | sizeof(*mod->ftrace_callsites), |
3344 | &mod->num_ftrace_callsites); | |
3345 | #endif | |
540adea3 MH |
3346 | #ifdef CONFIG_FUNCTION_ERROR_INJECTION |
3347 | mod->ei_funcs = section_objs(info, "_error_injection_whitelist", | |
3348 | sizeof(*mod->ei_funcs), | |
3349 | &mod->num_ei_funcs); | |
1e6769b0 MH |
3350 | #endif |
3351 | #ifdef CONFIG_KPROBES | |
3352 | mod->kprobes_text_start = section_objs(info, ".kprobes.text", 1, | |
3353 | &mod->kprobes_text_size); | |
16db6264 MH |
3354 | mod->kprobe_blacklist = section_objs(info, "_kprobe_blacklist", |
3355 | sizeof(unsigned long), | |
3356 | &mod->num_kprobe_blacklist); | |
9183c3f9 JP |
3357 | #endif |
3358 | #ifdef CONFIG_HAVE_STATIC_CALL_INLINE | |
3359 | mod->static_call_sites = section_objs(info, ".static_call_sites", | |
3360 | sizeof(*mod->static_call_sites), | |
3361 | &mod->num_static_call_sites); | |
92ace999 | 3362 | #endif |
811d66a0 RR |
3363 | mod->extable = section_objs(info, "__ex_table", |
3364 | sizeof(*mod->extable), &mod->num_exentries); | |
3365 | ||
49668688 | 3366 | if (section_addr(info, "__obsparm")) |
bddb12b3 | 3367 | pr_warn("%s: Ignoring obsolete parameters\n", mod->name); |
811d66a0 | 3368 | |
e5ebffe1 | 3369 | info->debug = section_objs(info, "__dyndbg", |
811d66a0 | 3370 | sizeof(*info->debug), &info->num_debug); |
eb3057df FH |
3371 | |
3372 | return 0; | |
f91a13bb LT |
3373 | } |
3374 | ||
49668688 | 3375 | static int move_module(struct module *mod, struct load_info *info) |
65b8a9b4 LT |
3376 | { |
3377 | int i; | |
3378 | void *ptr; | |
3379 | ||
3380 | /* Do the allocs. */ | |
7523e4dc | 3381 | ptr = module_alloc(mod->core_layout.size); |
65b8a9b4 LT |
3382 | /* |
3383 | * The pointer to this block is stored in the module structure | |
3384 | * which is inside the block. Just mark it as not being a | |
3385 | * leak. | |
3386 | */ | |
3387 | kmemleak_not_leak(ptr); | |
3388 | if (!ptr) | |
d913188c | 3389 | return -ENOMEM; |
65b8a9b4 | 3390 | |
7523e4dc RR |
3391 | memset(ptr, 0, mod->core_layout.size); |
3392 | mod->core_layout.base = ptr; | |
65b8a9b4 | 3393 | |
7523e4dc RR |
3394 | if (mod->init_layout.size) { |
3395 | ptr = module_alloc(mod->init_layout.size); | |
82fab442 RR |
3396 | /* |
3397 | * The pointer to this block is stored in the module structure | |
3398 | * which is inside the block. This block doesn't need to be | |
3399 | * scanned as it contains data and code that will be freed | |
3400 | * after the module is initialized. | |
3401 | */ | |
3402 | kmemleak_ignore(ptr); | |
3403 | if (!ptr) { | |
7523e4dc | 3404 | module_memfree(mod->core_layout.base); |
82fab442 RR |
3405 | return -ENOMEM; |
3406 | } | |
7523e4dc RR |
3407 | memset(ptr, 0, mod->init_layout.size); |
3408 | mod->init_layout.base = ptr; | |
82fab442 | 3409 | } else |
7523e4dc | 3410 | mod->init_layout.base = NULL; |
65b8a9b4 LT |
3411 | |
3412 | /* Transfer each section which specifies SHF_ALLOC */ | |
5e124169 | 3413 | pr_debug("final section addresses:\n"); |
49668688 | 3414 | for (i = 0; i < info->hdr->e_shnum; i++) { |
65b8a9b4 | 3415 | void *dest; |
49668688 | 3416 | Elf_Shdr *shdr = &info->sechdrs[i]; |
65b8a9b4 | 3417 | |
49668688 | 3418 | if (!(shdr->sh_flags & SHF_ALLOC)) |
65b8a9b4 LT |
3419 | continue; |
3420 | ||
49668688 | 3421 | if (shdr->sh_entsize & INIT_OFFSET_MASK) |
7523e4dc | 3422 | dest = mod->init_layout.base |
49668688 | 3423 | + (shdr->sh_entsize & ~INIT_OFFSET_MASK); |
65b8a9b4 | 3424 | else |
7523e4dc | 3425 | dest = mod->core_layout.base + shdr->sh_entsize; |
65b8a9b4 | 3426 | |
49668688 RR |
3427 | if (shdr->sh_type != SHT_NOBITS) |
3428 | memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size); | |
65b8a9b4 | 3429 | /* Update sh_addr to point to copy in image. */ |
49668688 | 3430 | shdr->sh_addr = (unsigned long)dest; |
5e124169 JC |
3431 | pr_debug("\t0x%lx %s\n", |
3432 | (long)shdr->sh_addr, info->secstrings + shdr->sh_name); | |
65b8a9b4 | 3433 | } |
d913188c RR |
3434 | |
3435 | return 0; | |
65b8a9b4 LT |
3436 | } |
3437 | ||
49668688 | 3438 | static int check_module_license_and_versions(struct module *mod) |
22e268eb | 3439 | { |
3205c36c LP |
3440 | int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE); |
3441 | ||
22e268eb RR |
3442 | /* |
3443 | * ndiswrapper is under GPL by itself, but loads proprietary modules. | |
3444 | * Don't use add_taint_module(), as it would prevent ndiswrapper from | |
3445 | * using GPL-only symbols it needs. | |
3446 | */ | |
3447 | if (strcmp(mod->name, "ndiswrapper") == 0) | |
373d4d09 | 3448 | add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE); |
22e268eb RR |
3449 | |
3450 | /* driverloader was caught wrongly pretending to be under GPL */ | |
3451 | if (strcmp(mod->name, "driverloader") == 0) | |
373d4d09 RR |
3452 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
3453 | LOCKDEP_NOW_UNRELIABLE); | |
22e268eb | 3454 | |
c99af375 MG |
3455 | /* lve claims to be GPL but upstream won't provide source */ |
3456 | if (strcmp(mod->name, "lve") == 0) | |
373d4d09 RR |
3457 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
3458 | LOCKDEP_NOW_UNRELIABLE); | |
c99af375 | 3459 | |
3205c36c LP |
3460 | if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE)) |
3461 | pr_warn("%s: module license taints kernel.\n", mod->name); | |
3462 | ||
22e268eb | 3463 | #ifdef CONFIG_MODVERSIONS |
36794822 CH |
3464 | if ((mod->num_syms && !mod->crcs) || |
3465 | (mod->num_gpl_syms && !mod->gpl_crcs)) { | |
22e268eb RR |
3466 | return try_to_force_load(mod, |
3467 | "no versions for exported symbols"); | |
3468 | } | |
3469 | #endif | |
3470 | return 0; | |
3471 | } | |
3472 | ||
3473 | static void flush_module_icache(const struct module *mod) | |
3474 | { | |
22e268eb RR |
3475 | /* |
3476 | * Flush the instruction cache, since we've played with text. | |
3477 | * Do it before processing of module parameters, so the module | |
3478 | * can provide parameter accessor functions of its own. | |
3479 | */ | |
7523e4dc RR |
3480 | if (mod->init_layout.base) |
3481 | flush_icache_range((unsigned long)mod->init_layout.base, | |
3482 | (unsigned long)mod->init_layout.base | |
3483 | + mod->init_layout.size); | |
3484 | flush_icache_range((unsigned long)mod->core_layout.base, | |
3485 | (unsigned long)mod->core_layout.base + mod->core_layout.size); | |
22e268eb RR |
3486 | } |
3487 | ||
74e08fcf JB |
3488 | int __weak module_frob_arch_sections(Elf_Ehdr *hdr, |
3489 | Elf_Shdr *sechdrs, | |
3490 | char *secstrings, | |
3491 | struct module *mod) | |
3492 | { | |
3493 | return 0; | |
3494 | } | |
3495 | ||
be7de5f9 PB |
3496 | /* module_blacklist is a comma-separated list of module names */ |
3497 | static char *module_blacklist; | |
96b5b194 | 3498 | static bool blacklisted(const char *module_name) |
be7de5f9 PB |
3499 | { |
3500 | const char *p; | |
3501 | size_t len; | |
3502 | ||
3503 | if (!module_blacklist) | |
3504 | return false; | |
3505 | ||
3506 | for (p = module_blacklist; *p; p += len) { | |
3507 | len = strcspn(p, ","); | |
3508 | if (strlen(module_name) == len && !memcmp(module_name, p, len)) | |
3509 | return true; | |
3510 | if (p[len] == ',') | |
3511 | len++; | |
3512 | } | |
3513 | return false; | |
3514 | } | |
3515 | core_param(module_blacklist, module_blacklist, charp, 0400); | |
3516 | ||
2f3238ae | 3517 | static struct module *layout_and_allocate(struct load_info *info, int flags) |
1da177e4 | 3518 | { |
1da177e4 | 3519 | struct module *mod; |
444d13ff | 3520 | unsigned int ndx; |
d913188c | 3521 | int err; |
3ae91c21 | 3522 | |
81a0abd9 | 3523 | err = check_modinfo(info->mod, info, flags); |
40dd2560 RR |
3524 | if (err) |
3525 | return ERR_PTR(err); | |
1da177e4 | 3526 | |
1da177e4 | 3527 | /* Allow arches to frob section contents and sizes. */ |
49668688 | 3528 | err = module_frob_arch_sections(info->hdr, info->sechdrs, |
81a0abd9 | 3529 | info->secstrings, info->mod); |
1da177e4 | 3530 | if (err < 0) |
8d8022e8 | 3531 | return ERR_PTR(err); |
1da177e4 | 3532 | |
5c3a7db0 PZ |
3533 | err = module_enforce_rwx_sections(info->hdr, info->sechdrs, |
3534 | info->secstrings, info->mod); | |
3535 | if (err < 0) | |
3536 | return ERR_PTR(err); | |
3537 | ||
8d8022e8 RR |
3538 | /* We will do a special allocation for per-cpu sections later. */ |
3539 | info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
1da177e4 | 3540 | |
444d13ff JY |
3541 | /* |
3542 | * Mark ro_after_init section with SHF_RO_AFTER_INIT so that | |
3543 | * layout_sections() can put it in the right place. | |
3544 | * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set. | |
3545 | */ | |
3546 | ndx = find_sec(info, ".data..ro_after_init"); | |
e872267b AB |
3547 | if (ndx) |
3548 | info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT; | |
3549 | /* | |
3550 | * Mark the __jump_table section as ro_after_init as well: these data | |
3551 | * structures are never modified, with the exception of entries that | |
3552 | * refer to code in the __init section, which are annotated as such | |
3553 | * at module load time. | |
3554 | */ | |
3555 | ndx = find_sec(info, "__jump_table"); | |
444d13ff JY |
3556 | if (ndx) |
3557 | info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT; | |
3558 | ||
24b9f0d2 SS |
3559 | /* |
3560 | * Determine total sizes, and put offsets in sh_entsize. For now | |
3561 | * this is done generically; there doesn't appear to be any | |
3562 | * special cases for the architectures. | |
3563 | */ | |
81a0abd9 JY |
3564 | layout_sections(info->mod, info); |
3565 | layout_symtab(info->mod, info); | |
1da177e4 | 3566 | |
65b8a9b4 | 3567 | /* Allocate and move to the final place */ |
81a0abd9 | 3568 | err = move_module(info->mod, info); |
d913188c | 3569 | if (err) |
8d8022e8 | 3570 | return ERR_PTR(err); |
d913188c RR |
3571 | |
3572 | /* Module has been copied to its final place now: return it. */ | |
3573 | mod = (void *)info->sechdrs[info->index.mod].sh_addr; | |
49668688 | 3574 | kmemleak_load_module(mod, info); |
d913188c | 3575 | return mod; |
d913188c RR |
3576 | } |
3577 | ||
3578 | /* mod is no longer valid after this! */ | |
3579 | static void module_deallocate(struct module *mod, struct load_info *info) | |
3580 | { | |
d913188c | 3581 | percpu_modfree(mod); |
d453cded | 3582 | module_arch_freeing_init(mod); |
7523e4dc RR |
3583 | module_memfree(mod->init_layout.base); |
3584 | module_memfree(mod->core_layout.base); | |
d913188c RR |
3585 | } |
3586 | ||
74e08fcf JB |
3587 | int __weak module_finalize(const Elf_Ehdr *hdr, |
3588 | const Elf_Shdr *sechdrs, | |
3589 | struct module *me) | |
3590 | { | |
3591 | return 0; | |
3592 | } | |
3593 | ||
811d66a0 RR |
3594 | static int post_relocation(struct module *mod, const struct load_info *info) |
3595 | { | |
51f3d0f4 | 3596 | /* Sort exception table now relocations are done. */ |
811d66a0 RR |
3597 | sort_extable(mod->extable, mod->extable + mod->num_exentries); |
3598 | ||
3599 | /* Copy relocated percpu area over. */ | |
3600 | percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr, | |
3601 | info->sechdrs[info->index.pcpu].sh_size); | |
3602 | ||
51f3d0f4 | 3603 | /* Setup kallsyms-specific fields. */ |
811d66a0 RR |
3604 | add_kallsyms(mod, info); |
3605 | ||
3606 | /* Arch-specific module finalizing. */ | |
3607 | return module_finalize(info->hdr, info->sechdrs, mod); | |
3608 | } | |
3609 | ||
9bb9c3be RR |
3610 | /* Is this module of this name done loading? No locks held. */ |
3611 | static bool finished_loading(const char *name) | |
3612 | { | |
3613 | struct module *mod; | |
3614 | bool ret; | |
3615 | ||
9cc019b8 PZ |
3616 | /* |
3617 | * The module_mutex should not be a heavily contended lock; | |
3618 | * if we get the occasional sleep here, we'll go an extra iteration | |
3619 | * in the wait_event_interruptible(), which is harmless. | |
3620 | */ | |
3621 | sched_annotate_sleep(); | |
9bb9c3be | 3622 | mutex_lock(&module_mutex); |
4f6de4d5 | 3623 | mod = find_module_all(name, strlen(name), true); |
6e6de3de | 3624 | ret = !mod || mod->state == MODULE_STATE_LIVE; |
9bb9c3be RR |
3625 | mutex_unlock(&module_mutex); |
3626 | ||
3627 | return ret; | |
3628 | } | |
3629 | ||
34e1169d KC |
3630 | /* Call module constructors. */ |
3631 | static void do_mod_ctors(struct module *mod) | |
3632 | { | |
3633 | #ifdef CONFIG_CONSTRUCTORS | |
3634 | unsigned long i; | |
3635 | ||
3636 | for (i = 0; i < mod->num_ctors; i++) | |
3637 | mod->ctors[i](); | |
3638 | #endif | |
3639 | } | |
3640 | ||
c7496379 RR |
3641 | /* For freeing module_init on success, in case kallsyms traversing */ |
3642 | struct mod_initfree { | |
1a7b7d92 | 3643 | struct llist_node node; |
c7496379 RR |
3644 | void *module_init; |
3645 | }; | |
3646 | ||
1a7b7d92 | 3647 | static void do_free_init(struct work_struct *w) |
c7496379 | 3648 | { |
1a7b7d92 RE |
3649 | struct llist_node *pos, *n, *list; |
3650 | struct mod_initfree *initfree; | |
3651 | ||
3652 | list = llist_del_all(&init_free_list); | |
3653 | ||
3654 | synchronize_rcu(); | |
3655 | ||
3656 | llist_for_each_safe(pos, n, list) { | |
3657 | initfree = container_of(pos, struct mod_initfree, node); | |
3658 | module_memfree(initfree->module_init); | |
3659 | kfree(initfree); | |
3660 | } | |
c7496379 RR |
3661 | } |
3662 | ||
be02a186 JK |
3663 | /* |
3664 | * This is where the real work happens. | |
3665 | * | |
3666 | * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb | |
3667 | * helper command 'lx-symbols'. | |
3668 | */ | |
3669 | static noinline int do_init_module(struct module *mod) | |
34e1169d KC |
3670 | { |
3671 | int ret = 0; | |
c7496379 RR |
3672 | struct mod_initfree *freeinit; |
3673 | ||
3674 | freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL); | |
3675 | if (!freeinit) { | |
3676 | ret = -ENOMEM; | |
3677 | goto fail; | |
3678 | } | |
7523e4dc | 3679 | freeinit->module_init = mod->init_layout.base; |
34e1169d | 3680 | |
774a1221 TH |
3681 | /* |
3682 | * We want to find out whether @mod uses async during init. Clear | |
3683 | * PF_USED_ASYNC. async_schedule*() will set it. | |
3684 | */ | |
3685 | current->flags &= ~PF_USED_ASYNC; | |
3686 | ||
34e1169d KC |
3687 | do_mod_ctors(mod); |
3688 | /* Start the module */ | |
3689 | if (mod->init != NULL) | |
3690 | ret = do_one_initcall(mod->init); | |
3691 | if (ret < 0) { | |
c7496379 | 3692 | goto fail_free_freeinit; |
34e1169d KC |
3693 | } |
3694 | if (ret > 0) { | |
bddb12b3 AM |
3695 | pr_warn("%s: '%s'->init suspiciously returned %d, it should " |
3696 | "follow 0/-E convention\n" | |
3697 | "%s: loading module anyway...\n", | |
3698 | __func__, mod->name, ret, __func__); | |
34e1169d KC |
3699 | dump_stack(); |
3700 | } | |
3701 | ||
3702 | /* Now it's a first class citizen! */ | |
3703 | mod->state = MODULE_STATE_LIVE; | |
3704 | blocking_notifier_call_chain(&module_notify_list, | |
3705 | MODULE_STATE_LIVE, mod); | |
3706 | ||
38dc717e JY |
3707 | /* Delay uevent until module has finished its init routine */ |
3708 | kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD); | |
3709 | ||
774a1221 TH |
3710 | /* |
3711 | * We need to finish all async code before the module init sequence | |
3712 | * is done. This has potential to deadlock. For example, a newly | |
3713 | * detected block device can trigger request_module() of the | |
3714 | * default iosched from async probing task. Once userland helper | |
3715 | * reaches here, async_synchronize_full() will wait on the async | |
3716 | * task waiting on request_module() and deadlock. | |
3717 | * | |
3718 | * This deadlock is avoided by perfomring async_synchronize_full() | |
3719 | * iff module init queued any async jobs. This isn't a full | |
3720 | * solution as it will deadlock the same if module loading from | |
3721 | * async jobs nests more than once; however, due to the various | |
3722 | * constraints, this hack seems to be the best option for now. | |
3723 | * Please refer to the following thread for details. | |
3724 | * | |
3725 | * http://thread.gmane.org/gmane.linux.kernel/1420814 | |
3726 | */ | |
f2411da7 | 3727 | if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC)) |
774a1221 | 3728 | async_synchronize_full(); |
34e1169d | 3729 | |
aba4b5c2 | 3730 | ftrace_free_mem(mod, mod->init_layout.base, mod->init_layout.base + |
3e234289 | 3731 | mod->init_layout.size); |
34e1169d KC |
3732 | mutex_lock(&module_mutex); |
3733 | /* Drop initial reference. */ | |
3734 | module_put(mod); | |
3735 | trim_init_extable(mod); | |
3736 | #ifdef CONFIG_KALLSYMS | |
8244062e RR |
3737 | /* Switch to core kallsyms now init is done: kallsyms may be walking! */ |
3738 | rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms); | |
34e1169d | 3739 | #endif |
444d13ff | 3740 | module_enable_ro(mod, true); |
93c2e105 | 3741 | mod_tree_remove_init(mod); |
d453cded | 3742 | module_arch_freeing_init(mod); |
7523e4dc RR |
3743 | mod->init_layout.base = NULL; |
3744 | mod->init_layout.size = 0; | |
3745 | mod->init_layout.ro_size = 0; | |
444d13ff | 3746 | mod->init_layout.ro_after_init_size = 0; |
7523e4dc | 3747 | mod->init_layout.text_size = 0; |
607c543f AN |
3748 | #ifdef CONFIG_DEBUG_INFO_BTF_MODULES |
3749 | /* .BTF is not SHF_ALLOC and will get removed, so sanitize pointer */ | |
3750 | mod->btf_data = NULL; | |
607c543f | 3751 | #endif |
c7496379 RR |
3752 | /* |
3753 | * We want to free module_init, but be aware that kallsyms may be | |
0be964be | 3754 | * walking this with preempt disabled. In all the failure paths, we |
cb2f5536 | 3755 | * call synchronize_rcu(), but we don't want to slow down the success |
1a7b7d92 RE |
3756 | * path. module_memfree() cannot be called in an interrupt, so do the |
3757 | * work and call synchronize_rcu() in a work queue. | |
3758 | * | |
ae646f0b JH |
3759 | * Note that module_alloc() on most architectures creates W+X page |
3760 | * mappings which won't be cleaned up until do_free_init() runs. Any | |
3761 | * code such as mark_rodata_ro() which depends on those mappings to | |
3762 | * be cleaned up needs to sync with the queued work - ie | |
cb2f5536 | 3763 | * rcu_barrier() |
c7496379 | 3764 | */ |
1a7b7d92 RE |
3765 | if (llist_add(&freeinit->node, &init_free_list)) |
3766 | schedule_work(&init_free_wq); | |
3767 | ||
34e1169d KC |
3768 | mutex_unlock(&module_mutex); |
3769 | wake_up_all(&module_wq); | |
3770 | ||
3771 | return 0; | |
c7496379 RR |
3772 | |
3773 | fail_free_freeinit: | |
3774 | kfree(freeinit); | |
3775 | fail: | |
3776 | /* Try to protect us from buggy refcounters. */ | |
3777 | mod->state = MODULE_STATE_GOING; | |
cb2f5536 | 3778 | synchronize_rcu(); |
c7496379 RR |
3779 | module_put(mod); |
3780 | blocking_notifier_call_chain(&module_notify_list, | |
3781 | MODULE_STATE_GOING, mod); | |
7e545d6e | 3782 | klp_module_going(mod); |
7dcd182b | 3783 | ftrace_release_mod(mod); |
c7496379 RR |
3784 | free_module(mod); |
3785 | wake_up_all(&module_wq); | |
3786 | return ret; | |
34e1169d KC |
3787 | } |
3788 | ||
3789 | static int may_init_module(void) | |
3790 | { | |
3791 | if (!capable(CAP_SYS_MODULE) || modules_disabled) | |
3792 | return -EPERM; | |
3793 | ||
3794 | return 0; | |
3795 | } | |
3796 | ||
a3535c7e RR |
3797 | /* |
3798 | * We try to place it in the list now to make sure it's unique before | |
3799 | * we dedicate too many resources. In particular, temporary percpu | |
3800 | * memory exhaustion. | |
3801 | */ | |
3802 | static int add_unformed_module(struct module *mod) | |
3803 | { | |
3804 | int err; | |
3805 | struct module *old; | |
3806 | ||
3807 | mod->state = MODULE_STATE_UNFORMED; | |
3808 | ||
3809 | again: | |
3810 | mutex_lock(&module_mutex); | |
4f6de4d5 MK |
3811 | old = find_module_all(mod->name, strlen(mod->name), true); |
3812 | if (old != NULL) { | |
6e6de3de | 3813 | if (old->state != MODULE_STATE_LIVE) { |
a3535c7e RR |
3814 | /* Wait in case it fails to load. */ |
3815 | mutex_unlock(&module_mutex); | |
9cc019b8 PZ |
3816 | err = wait_event_interruptible(module_wq, |
3817 | finished_loading(mod->name)); | |
a3535c7e RR |
3818 | if (err) |
3819 | goto out_unlocked; | |
3820 | goto again; | |
3821 | } | |
3822 | err = -EEXIST; | |
3823 | goto out; | |
3824 | } | |
4f666546 | 3825 | mod_update_bounds(mod); |
a3535c7e | 3826 | list_add_rcu(&mod->list, &modules); |
93c2e105 | 3827 | mod_tree_insert(mod); |
a3535c7e RR |
3828 | err = 0; |
3829 | ||
3830 | out: | |
3831 | mutex_unlock(&module_mutex); | |
3832 | out_unlocked: | |
3833 | return err; | |
3834 | } | |
3835 | ||
3836 | static int complete_formation(struct module *mod, struct load_info *info) | |
3837 | { | |
3838 | int err; | |
3839 | ||
3840 | mutex_lock(&module_mutex); | |
3841 | ||
3842 | /* Find duplicate symbols (must be called under lock). */ | |
2d25bc55 | 3843 | err = verify_exported_symbols(mod); |
a3535c7e RR |
3844 | if (err < 0) |
3845 | goto out; | |
3846 | ||
3847 | /* This relies on module_mutex for list integrity. */ | |
3848 | module_bug_finalize(info->hdr, info->sechdrs, mod); | |
3849 | ||
444d13ff | 3850 | module_enable_ro(mod, false); |
85c898db | 3851 | module_enable_nx(mod); |
af742623 | 3852 | module_enable_x(mod); |
4982223e | 3853 | |
24b9f0d2 SS |
3854 | /* |
3855 | * Mark state as coming so strong_try_module_get() ignores us, | |
3856 | * but kallsyms etc. can see us. | |
3857 | */ | |
a3535c7e | 3858 | mod->state = MODULE_STATE_COMING; |
4982223e RR |
3859 | mutex_unlock(&module_mutex); |
3860 | ||
4982223e | 3861 | return 0; |
a3535c7e RR |
3862 | |
3863 | out: | |
3864 | mutex_unlock(&module_mutex); | |
3865 | return err; | |
3866 | } | |
3867 | ||
4c973d16 JY |
3868 | static int prepare_coming_module(struct module *mod) |
3869 | { | |
7e545d6e JY |
3870 | int err; |
3871 | ||
4c973d16 | 3872 | ftrace_module_enable(mod); |
7e545d6e JY |
3873 | err = klp_module_coming(mod); |
3874 | if (err) | |
3875 | return err; | |
3876 | ||
59cc8e0a PZ |
3877 | err = blocking_notifier_call_chain_robust(&module_notify_list, |
3878 | MODULE_STATE_COMING, MODULE_STATE_GOING, mod); | |
3879 | err = notifier_to_errno(err); | |
3880 | if (err) | |
3881 | klp_module_going(mod); | |
3882 | ||
3883 | return err; | |
4c973d16 JY |
3884 | } |
3885 | ||
ecc86170 LR |
3886 | static int unknown_module_param_cb(char *param, char *val, const char *modname, |
3887 | void *arg) | |
54041d8a | 3888 | { |
f2411da7 LR |
3889 | struct module *mod = arg; |
3890 | int ret; | |
3891 | ||
3892 | if (strcmp(param, "async_probe") == 0) { | |
3893 | mod->async_probe_requested = true; | |
3894 | return 0; | |
3895 | } | |
3896 | ||
6da0b565 | 3897 | /* Check for magic 'dyndbg' arg */ |
f2411da7 | 3898 | ret = ddebug_dyndbg_module_param_cb(param, val, modname); |
bddb12b3 AM |
3899 | if (ret != 0) |
3900 | pr_warn("%s: unknown parameter '%s' ignored\n", modname, param); | |
54041d8a RR |
3901 | return 0; |
3902 | } | |
3903 | ||
cf68fffb ST |
3904 | static void cfi_init(struct module *mod); |
3905 | ||
24b9f0d2 SS |
3906 | /* |
3907 | * Allocate and load the module: note that size of section 0 is always | |
3908 | * zero, and we rely on this for optional sections. | |
3909 | */ | |
2f3238ae RR |
3910 | static int load_module(struct load_info *info, const char __user *uargs, |
3911 | int flags) | |
d913188c | 3912 | { |
a3535c7e | 3913 | struct module *mod; |
5fdc7db6 | 3914 | long err = 0; |
51e158c1 | 3915 | char *after_dashes; |
d913188c | 3916 | |
ec2a2959 FL |
3917 | /* |
3918 | * Do the signature check (if any) first. All that | |
3919 | * the signature check needs is info->len, it does | |
3920 | * not need any of the section info. That can be | |
3921 | * set up later. This will minimize the chances | |
3922 | * of a corrupt module causing problems before | |
3923 | * we even get to the signature check. | |
3924 | * | |
3925 | * The check will also adjust info->len by stripping | |
3926 | * off the sig length at the end of the module, making | |
3927 | * checks against info->len more correct. | |
3928 | */ | |
3929 | err = module_sig_check(info, flags); | |
3930 | if (err) | |
3931 | goto free_copy; | |
3932 | ||
3933 | /* | |
3934 | * Do basic sanity checks against the ELF header and | |
3935 | * sections. | |
3936 | */ | |
3937 | err = elf_validity_check(info); | |
14721add | 3938 | if (err) { |
ec2a2959 | 3939 | pr_err("Module has invalid ELF structures\n"); |
5fdc7db6 | 3940 | goto free_copy; |
14721add | 3941 | } |
5fdc7db6 | 3942 | |
ec2a2959 FL |
3943 | /* |
3944 | * Everything checks out, so set up the section info | |
3945 | * in the info structure. | |
3946 | */ | |
5fdc7db6 JY |
3947 | err = setup_load_info(info, flags); |
3948 | if (err) | |
3949 | goto free_copy; | |
3950 | ||
ec2a2959 FL |
3951 | /* |
3952 | * Now that we know we have the correct module name, check | |
3953 | * if it's blacklisted. | |
3954 | */ | |
5fdc7db6 JY |
3955 | if (blacklisted(info->name)) { |
3956 | err = -EPERM; | |
14721add | 3957 | pr_err("Module %s is blacklisted\n", info->name); |
5fdc7db6 JY |
3958 | goto free_copy; |
3959 | } | |
3960 | ||
5fdc7db6 | 3961 | err = rewrite_section_headers(info, flags); |
d913188c | 3962 | if (err) |
34e1169d | 3963 | goto free_copy; |
d913188c | 3964 | |
5fdc7db6 JY |
3965 | /* Check module struct version now, before we try to use module. */ |
3966 | if (!check_modstruct_version(info, info->mod)) { | |
3967 | err = -ENOEXEC; | |
3968 | goto free_copy; | |
3969 | } | |
3970 | ||
d913188c | 3971 | /* Figure out module layout, and allocate all the memory. */ |
2f3238ae | 3972 | mod = layout_and_allocate(info, flags); |
65b8a9b4 LT |
3973 | if (IS_ERR(mod)) { |
3974 | err = PTR_ERR(mod); | |
d913188c | 3975 | goto free_copy; |
1da177e4 | 3976 | } |
1da177e4 | 3977 | |
ca86cad7 RGB |
3978 | audit_log_kern_module(mod->name); |
3979 | ||
a3535c7e RR |
3980 | /* Reserve our place in the list. */ |
3981 | err = add_unformed_module(mod); | |
3982 | if (err) | |
1fb9341a | 3983 | goto free_module; |
1fb9341a | 3984 | |
106a4ee2 | 3985 | #ifdef CONFIG_MODULE_SIG |
34e1169d | 3986 | mod->sig_ok = info->sig_ok; |
64748a2c | 3987 | if (!mod->sig_ok) { |
bddb12b3 | 3988 | pr_notice_once("%s: module verification failed: signature " |
ab92ebbb | 3989 | "and/or required key missing - tainting " |
bddb12b3 | 3990 | "kernel\n", mod->name); |
66cc69e3 | 3991 | add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK); |
64748a2c | 3992 | } |
106a4ee2 RR |
3993 | #endif |
3994 | ||
8d8022e8 | 3995 | /* To avoid stressing percpu allocator, do this once we're unique. */ |
9eb76d77 | 3996 | err = percpu_modalloc(mod, info); |
8d8022e8 RR |
3997 | if (err) |
3998 | goto unlink_mod; | |
3999 | ||
49668688 | 4000 | /* Now module is in final location, initialize linked lists, etc. */ |
9f85a4bb RR |
4001 | err = module_unload_init(mod); |
4002 | if (err) | |
1fb9341a | 4003 | goto unlink_mod; |
1da177e4 | 4004 | |
cf2fde7b | 4005 | init_param_lock(mod); |
b51d23e4 | 4006 | |
24b9f0d2 SS |
4007 | /* |
4008 | * Now we've got everything in the final locations, we can | |
4009 | * find optional sections. | |
4010 | */ | |
eb3057df FH |
4011 | err = find_module_sections(mod, info); |
4012 | if (err) | |
4013 | goto free_unload; | |
9b37ccfc | 4014 | |
49668688 | 4015 | err = check_module_license_and_versions(mod); |
22e268eb RR |
4016 | if (err) |
4017 | goto free_unload; | |
9841d61d | 4018 | |
c988d2b2 | 4019 | /* Set up MODINFO_ATTR fields */ |
34e1169d | 4020 | setup_modinfo(mod, info); |
c988d2b2 | 4021 | |
1da177e4 | 4022 | /* Fix up syms, so that st_value is a pointer to location. */ |
34e1169d | 4023 | err = simplify_symbols(mod, info); |
1da177e4 | 4024 | if (err < 0) |
d913188c | 4025 | goto free_modinfo; |
1da177e4 | 4026 | |
34e1169d | 4027 | err = apply_relocations(mod, info); |
22e268eb | 4028 | if (err < 0) |
d913188c | 4029 | goto free_modinfo; |
1da177e4 | 4030 | |
34e1169d | 4031 | err = post_relocation(mod, info); |
1da177e4 | 4032 | if (err < 0) |
d913188c | 4033 | goto free_modinfo; |
1da177e4 | 4034 | |
22e268eb | 4035 | flush_module_icache(mod); |
378bac82 | 4036 | |
cf68fffb ST |
4037 | /* Setup CFI for the module. */ |
4038 | cfi_init(mod); | |
4039 | ||
6526c534 RR |
4040 | /* Now copy in args */ |
4041 | mod->args = strndup_user(uargs, ~0UL >> 1); | |
4042 | if (IS_ERR(mod->args)) { | |
4043 | err = PTR_ERR(mod->args); | |
4044 | goto free_arch_cleanup; | |
4045 | } | |
8d3b33f6 | 4046 | |
9294523e | 4047 | init_build_id(mod, info); |
52796312 | 4048 | dynamic_debug_setup(mod, info->debug, info->num_debug); |
ff49d74a | 4049 | |
a949ae56 SRRH |
4050 | /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */ |
4051 | ftrace_module_init(mod); | |
4052 | ||
a3535c7e RR |
4053 | /* Finally it's fully formed, ready to start executing. */ |
4054 | err = complete_formation(mod, info); | |
4055 | if (err) | |
1fb9341a | 4056 | goto ddebug_cleanup; |
be593f4c | 4057 | |
4c973d16 JY |
4058 | err = prepare_coming_module(mod); |
4059 | if (err) | |
4060 | goto bug_cleanup; | |
4061 | ||
51f3d0f4 | 4062 | /* Module is ready to execute: parsing args may do that. */ |
51e158c1 | 4063 | after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, |
4355efbd | 4064 | -32768, 32767, mod, |
ecc86170 | 4065 | unknown_module_param_cb); |
51e158c1 RR |
4066 | if (IS_ERR(after_dashes)) { |
4067 | err = PTR_ERR(after_dashes); | |
4c973d16 | 4068 | goto coming_cleanup; |
51e158c1 RR |
4069 | } else if (after_dashes) { |
4070 | pr_warn("%s: parameters '%s' after `--' ignored\n", | |
4071 | mod->name, after_dashes); | |
4072 | } | |
1da177e4 | 4073 | |
ca86cad7 | 4074 | /* Link in to sysfs. */ |
34e1169d | 4075 | err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp); |
1da177e4 | 4076 | if (err < 0) |
4c973d16 | 4077 | goto coming_cleanup; |
80a3d1bb | 4078 | |
1ce15ef4 JY |
4079 | if (is_livepatch_module(mod)) { |
4080 | err = copy_module_elf(mod, info); | |
4081 | if (err < 0) | |
4082 | goto sysfs_cleanup; | |
4083 | } | |
4084 | ||
48fd1188 | 4085 | /* Get rid of temporary copy. */ |
34e1169d | 4086 | free_copy(info); |
1da177e4 LT |
4087 | |
4088 | /* Done! */ | |
51f3d0f4 | 4089 | trace_module_load(mod); |
34e1169d KC |
4090 | |
4091 | return do_init_module(mod); | |
1da177e4 | 4092 | |
1ce15ef4 JY |
4093 | sysfs_cleanup: |
4094 | mod_sysfs_teardown(mod); | |
4c973d16 | 4095 | coming_cleanup: |
885a78d4 | 4096 | mod->state = MODULE_STATE_GOING; |
a5544880 | 4097 | destroy_params(mod->kp, mod->num_kp); |
4c973d16 JY |
4098 | blocking_notifier_call_chain(&module_notify_list, |
4099 | MODULE_STATE_GOING, mod); | |
7e545d6e | 4100 | klp_module_going(mod); |
1fb9341a | 4101 | bug_cleanup: |
5e8ed280 | 4102 | mod->state = MODULE_STATE_GOING; |
1fb9341a | 4103 | /* module_bug_cleanup needs module_mutex protection */ |
75676500 | 4104 | mutex_lock(&module_mutex); |
5336377d | 4105 | module_bug_cleanup(mod); |
ee61abb3 | 4106 | mutex_unlock(&module_mutex); |
ff7e0055 | 4107 | |
a3535c7e | 4108 | ddebug_cleanup: |
1323eac7 | 4109 | ftrace_release_mod(mod); |
52796312 | 4110 | dynamic_debug_remove(mod, info->debug); |
cb2f5536 | 4111 | synchronize_rcu(); |
6526c534 RR |
4112 | kfree(mod->args); |
4113 | free_arch_cleanup: | |
cf68fffb | 4114 | cfi_cleanup(mod); |
1da177e4 | 4115 | module_arch_cleanup(mod); |
d913188c | 4116 | free_modinfo: |
a263f776 | 4117 | free_modinfo(mod); |
22e268eb | 4118 | free_unload: |
1da177e4 | 4119 | module_unload_free(mod); |
1fb9341a RR |
4120 | unlink_mod: |
4121 | mutex_lock(&module_mutex); | |
4122 | /* Unlink carefully: kallsyms could be walking list. */ | |
4123 | list_del_rcu(&mod->list); | |
758556bd | 4124 | mod_tree_remove(mod); |
1fb9341a | 4125 | wake_up_all(&module_wq); |
0be964be | 4126 | /* Wait for RCU-sched synchronizing before releasing mod->list. */ |
cb2f5536 | 4127 | synchronize_rcu(); |
1fb9341a | 4128 | mutex_unlock(&module_mutex); |
d913188c | 4129 | free_module: |
35a9393c | 4130 | /* Free lock-classes; relies on the preceding sync_rcu() */ |
7523e4dc | 4131 | lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size); |
35a9393c | 4132 | |
34e1169d | 4133 | module_deallocate(mod, info); |
d913188c | 4134 | free_copy: |
34e1169d KC |
4135 | free_copy(info); |
4136 | return err; | |
b99b87f7 PO |
4137 | } |
4138 | ||
17da2bd9 HC |
4139 | SYSCALL_DEFINE3(init_module, void __user *, umod, |
4140 | unsigned long, len, const char __user *, uargs) | |
1da177e4 | 4141 | { |
34e1169d KC |
4142 | int err; |
4143 | struct load_info info = { }; | |
1da177e4 | 4144 | |
34e1169d KC |
4145 | err = may_init_module(); |
4146 | if (err) | |
4147 | return err; | |
1da177e4 | 4148 | |
34e1169d KC |
4149 | pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n", |
4150 | umod, len, uargs); | |
1da177e4 | 4151 | |
34e1169d KC |
4152 | err = copy_module_from_user(umod, len, &info); |
4153 | if (err) | |
4154 | return err; | |
1da177e4 | 4155 | |
2f3238ae | 4156 | return load_module(&info, uargs, 0); |
34e1169d | 4157 | } |
94462ad3 | 4158 | |
2f3238ae | 4159 | SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) |
34e1169d | 4160 | { |
34e1169d | 4161 | struct load_info info = { }; |
c307459b | 4162 | void *hdr = NULL; |
a1db7420 | 4163 | int err; |
94462ad3 | 4164 | |
34e1169d KC |
4165 | err = may_init_module(); |
4166 | if (err) | |
4167 | return err; | |
1da177e4 | 4168 | |
2f3238ae | 4169 | pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags); |
6c5db22d | 4170 | |
2f3238ae RR |
4171 | if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS |
4172 | |MODULE_INIT_IGNORE_VERMAGIC)) | |
4173 | return -EINVAL; | |
d6de2c80 | 4174 | |
0fa8e084 | 4175 | err = kernel_read_file_from_fd(fd, 0, &hdr, INT_MAX, NULL, |
a1db7420 | 4176 | READING_MODULE); |
f7a4f689 | 4177 | if (err < 0) |
34e1169d | 4178 | return err; |
a1db7420 | 4179 | info.hdr = hdr; |
f7a4f689 | 4180 | info.len = err; |
1da177e4 | 4181 | |
2f3238ae | 4182 | return load_module(&info, uargs, flags); |
1da177e4 LT |
4183 | } |
4184 | ||
4185 | static inline int within(unsigned long addr, void *start, unsigned long size) | |
4186 | { | |
4187 | return ((void *)addr >= start && (void *)addr < start + size); | |
4188 | } | |
4189 | ||
4190 | #ifdef CONFIG_KALLSYMS | |
4191 | /* | |
4192 | * This ignores the intensely annoying "mapping symbols" found | |
4193 | * in ARM ELF files: $a, $t and $d. | |
4194 | */ | |
4195 | static inline int is_arm_mapping_symbol(const char *str) | |
4196 | { | |
2e3a10a1 RK |
4197 | if (str[0] == '.' && str[1] == 'L') |
4198 | return true; | |
6c34f1f5 | 4199 | return str[0] == '$' && strchr("axtd", str[1]) |
1da177e4 LT |
4200 | && (str[2] == '\0' || str[2] == '.'); |
4201 | } | |
4202 | ||
2d25bc55 | 4203 | static const char *kallsyms_symbol_name(struct mod_kallsyms *kallsyms, unsigned int symnum) |
2e7bac53 | 4204 | { |
8244062e | 4205 | return kallsyms->strtab + kallsyms->symtab[symnum].st_name; |
2e7bac53 RR |
4206 | } |
4207 | ||
2d25bc55 JY |
4208 | /* |
4209 | * Given a module and address, find the corresponding symbol and return its name | |
4210 | * while providing its size and offset if needed. | |
4211 | */ | |
4212 | static const char *find_kallsyms_symbol(struct module *mod, | |
4213 | unsigned long addr, | |
4214 | unsigned long *size, | |
4215 | unsigned long *offset) | |
1da177e4 LT |
4216 | { |
4217 | unsigned int i, best = 0; | |
93d77e7f | 4218 | unsigned long nextval, bestval; |
8244062e | 4219 | struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); |
1da177e4 LT |
4220 | |
4221 | /* At worse, next value is at end of module */ | |
a06f6211 | 4222 | if (within_module_init(addr, mod)) |
7523e4dc | 4223 | nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size; |
22a8bdeb | 4224 | else |
7523e4dc | 4225 | nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size; |
1da177e4 | 4226 | |
93d77e7f VW |
4227 | bestval = kallsyms_symbol_value(&kallsyms->symtab[best]); |
4228 | ||
24b9f0d2 SS |
4229 | /* |
4230 | * Scan for closest preceding symbol, and next symbol. (ELF | |
4231 | * starts real symbols at 1). | |
4232 | */ | |
8244062e | 4233 | for (i = 1; i < kallsyms->num_symtab; i++) { |
93d77e7f VW |
4234 | const Elf_Sym *sym = &kallsyms->symtab[i]; |
4235 | unsigned long thisval = kallsyms_symbol_value(sym); | |
4236 | ||
4237 | if (sym->st_shndx == SHN_UNDEF) | |
1da177e4 LT |
4238 | continue; |
4239 | ||
24b9f0d2 SS |
4240 | /* |
4241 | * We ignore unnamed symbols: they're uninformative | |
4242 | * and inserted at a whim. | |
4243 | */ | |
2d25bc55 JY |
4244 | if (*kallsyms_symbol_name(kallsyms, i) == '\0' |
4245 | || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms, i))) | |
2e7bac53 RR |
4246 | continue; |
4247 | ||
93d77e7f | 4248 | if (thisval <= addr && thisval > bestval) { |
1da177e4 | 4249 | best = i; |
93d77e7f VW |
4250 | bestval = thisval; |
4251 | } | |
4252 | if (thisval > addr && thisval < nextval) | |
4253 | nextval = thisval; | |
1da177e4 LT |
4254 | } |
4255 | ||
4256 | if (!best) | |
4257 | return NULL; | |
4258 | ||
ffb45122 | 4259 | if (size) |
93d77e7f | 4260 | *size = nextval - bestval; |
ffb45122 | 4261 | if (offset) |
93d77e7f | 4262 | *offset = addr - bestval; |
2d25bc55 JY |
4263 | |
4264 | return kallsyms_symbol_name(kallsyms, best); | |
1da177e4 LT |
4265 | } |
4266 | ||
b865ea64 SS |
4267 | void * __weak dereference_module_function_descriptor(struct module *mod, |
4268 | void *ptr) | |
4269 | { | |
4270 | return ptr; | |
4271 | } | |
4272 | ||
24b9f0d2 SS |
4273 | /* |
4274 | * For kallsyms to ask for address resolution. NULL means not found. Careful | |
4275 | * not to lock to avoid deadlock on oopses, simply disable preemption. | |
4276 | */ | |
92dfc9dc | 4277 | const char *module_address_lookup(unsigned long addr, |
6dd06c9f RR |
4278 | unsigned long *size, |
4279 | unsigned long *offset, | |
4280 | char **modname, | |
9294523e | 4281 | const unsigned char **modbuildid, |
6dd06c9f | 4282 | char *namebuf) |
1da177e4 | 4283 | { |
cb2a5205 | 4284 | const char *ret = NULL; |
b7df4d1b | 4285 | struct module *mod; |
1da177e4 | 4286 | |
cb2a5205 | 4287 | preempt_disable(); |
b7df4d1b PZ |
4288 | mod = __module_address(addr); |
4289 | if (mod) { | |
4290 | if (modname) | |
4291 | *modname = mod->name; | |
9294523e SB |
4292 | if (modbuildid) { |
4293 | #if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) | |
4294 | *modbuildid = mod->build_id; | |
4295 | #else | |
4296 | *modbuildid = NULL; | |
4297 | #endif | |
4298 | } | |
2d25bc55 JY |
4299 | |
4300 | ret = find_kallsyms_symbol(mod, addr, size, offset); | |
1da177e4 | 4301 | } |
6dd06c9f RR |
4302 | /* Make a copy in here where it's safe */ |
4303 | if (ret) { | |
4304 | strncpy(namebuf, ret, KSYM_NAME_LEN - 1); | |
4305 | ret = namebuf; | |
4306 | } | |
cb2a5205 | 4307 | preempt_enable(); |
b7df4d1b | 4308 | |
92dfc9dc | 4309 | return ret; |
1da177e4 LT |
4310 | } |
4311 | ||
9d65cb4a AD |
4312 | int lookup_module_symbol_name(unsigned long addr, char *symname) |
4313 | { | |
4314 | struct module *mod; | |
4315 | ||
cb2a5205 | 4316 | preempt_disable(); |
d72b3751 | 4317 | list_for_each_entry_rcu(mod, &modules, list) { |
0d21b0e3 RR |
4318 | if (mod->state == MODULE_STATE_UNFORMED) |
4319 | continue; | |
9b20a352 | 4320 | if (within_module(addr, mod)) { |
9d65cb4a AD |
4321 | const char *sym; |
4322 | ||
2d25bc55 | 4323 | sym = find_kallsyms_symbol(mod, addr, NULL, NULL); |
9d65cb4a AD |
4324 | if (!sym) |
4325 | goto out; | |
2d25bc55 | 4326 | |
9281acea | 4327 | strlcpy(symname, sym, KSYM_NAME_LEN); |
cb2a5205 | 4328 | preempt_enable(); |
9d65cb4a AD |
4329 | return 0; |
4330 | } | |
4331 | } | |
4332 | out: | |
cb2a5205 | 4333 | preempt_enable(); |
9d65cb4a AD |
4334 | return -ERANGE; |
4335 | } | |
4336 | ||
a5c43dae AD |
4337 | int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, |
4338 | unsigned long *offset, char *modname, char *name) | |
4339 | { | |
4340 | struct module *mod; | |
4341 | ||
cb2a5205 | 4342 | preempt_disable(); |
d72b3751 | 4343 | list_for_each_entry_rcu(mod, &modules, list) { |
0d21b0e3 RR |
4344 | if (mod->state == MODULE_STATE_UNFORMED) |
4345 | continue; | |
9b20a352 | 4346 | if (within_module(addr, mod)) { |
a5c43dae AD |
4347 | const char *sym; |
4348 | ||
2d25bc55 | 4349 | sym = find_kallsyms_symbol(mod, addr, size, offset); |
a5c43dae AD |
4350 | if (!sym) |
4351 | goto out; | |
4352 | if (modname) | |
9281acea | 4353 | strlcpy(modname, mod->name, MODULE_NAME_LEN); |
a5c43dae | 4354 | if (name) |
9281acea | 4355 | strlcpy(name, sym, KSYM_NAME_LEN); |
cb2a5205 | 4356 | preempt_enable(); |
a5c43dae AD |
4357 | return 0; |
4358 | } | |
4359 | } | |
4360 | out: | |
cb2a5205 | 4361 | preempt_enable(); |
a5c43dae AD |
4362 | return -ERANGE; |
4363 | } | |
4364 | ||
ea07890a AD |
4365 | int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, |
4366 | char *name, char *module_name, int *exported) | |
1da177e4 LT |
4367 | { |
4368 | struct module *mod; | |
4369 | ||
cb2a5205 | 4370 | preempt_disable(); |
d72b3751 | 4371 | list_for_each_entry_rcu(mod, &modules, list) { |
8244062e RR |
4372 | struct mod_kallsyms *kallsyms; |
4373 | ||
0d21b0e3 RR |
4374 | if (mod->state == MODULE_STATE_UNFORMED) |
4375 | continue; | |
8244062e RR |
4376 | kallsyms = rcu_dereference_sched(mod->kallsyms); |
4377 | if (symnum < kallsyms->num_symtab) { | |
93d77e7f VW |
4378 | const Elf_Sym *sym = &kallsyms->symtab[symnum]; |
4379 | ||
4380 | *value = kallsyms_symbol_value(sym); | |
1c7651f4 | 4381 | *type = kallsyms->typetab[symnum]; |
2d25bc55 | 4382 | strlcpy(name, kallsyms_symbol_name(kallsyms, symnum), KSYM_NAME_LEN); |
9281acea | 4383 | strlcpy(module_name, mod->name, MODULE_NAME_LEN); |
ca4787b7 | 4384 | *exported = is_exported(name, *value, mod); |
cb2a5205 | 4385 | preempt_enable(); |
ea07890a | 4386 | return 0; |
1da177e4 | 4387 | } |
8244062e | 4388 | symnum -= kallsyms->num_symtab; |
1da177e4 | 4389 | } |
cb2a5205 | 4390 | preempt_enable(); |
ea07890a | 4391 | return -ERANGE; |
1da177e4 LT |
4392 | } |
4393 | ||
2d25bc55 JY |
4394 | /* Given a module and name of symbol, find and return the symbol's value */ |
4395 | static unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name) | |
1da177e4 LT |
4396 | { |
4397 | unsigned int i; | |
8244062e | 4398 | struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); |
1da177e4 | 4399 | |
93d77e7f VW |
4400 | for (i = 0; i < kallsyms->num_symtab; i++) { |
4401 | const Elf_Sym *sym = &kallsyms->symtab[i]; | |
4402 | ||
2d25bc55 | 4403 | if (strcmp(name, kallsyms_symbol_name(kallsyms, i)) == 0 && |
93d77e7f VW |
4404 | sym->st_shndx != SHN_UNDEF) |
4405 | return kallsyms_symbol_value(sym); | |
4406 | } | |
1da177e4 LT |
4407 | return 0; |
4408 | } | |
4409 | ||
4410 | /* Look for this name: can be of form module:name. */ | |
4411 | unsigned long module_kallsyms_lookup_name(const char *name) | |
4412 | { | |
4413 | struct module *mod; | |
4414 | char *colon; | |
4415 | unsigned long ret = 0; | |
4416 | ||
4417 | /* Don't lock: we're in enough trouble already. */ | |
cb2a5205 | 4418 | preempt_disable(); |
17586188 | 4419 | if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) { |
4f6de4d5 | 4420 | if ((mod = find_module_all(name, colon - name, false)) != NULL) |
2d25bc55 | 4421 | ret = find_kallsyms_symbol_value(mod, colon+1); |
1da177e4 | 4422 | } else { |
0d21b0e3 RR |
4423 | list_for_each_entry_rcu(mod, &modules, list) { |
4424 | if (mod->state == MODULE_STATE_UNFORMED) | |
4425 | continue; | |
2d25bc55 | 4426 | if ((ret = find_kallsyms_symbol_value(mod, name)) != 0) |
1da177e4 | 4427 | break; |
0d21b0e3 | 4428 | } |
1da177e4 | 4429 | } |
cb2a5205 | 4430 | preempt_enable(); |
1da177e4 LT |
4431 | return ret; |
4432 | } | |
75a66614 | 4433 | |
3e355205 | 4434 | #ifdef CONFIG_LIVEPATCH |
75a66614 AK |
4435 | int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, |
4436 | struct module *, unsigned long), | |
4437 | void *data) | |
4438 | { | |
4439 | struct module *mod; | |
4440 | unsigned int i; | |
1e80d9cb | 4441 | int ret = 0; |
75a66614 | 4442 | |
013c1667 | 4443 | mutex_lock(&module_mutex); |
75a66614 | 4444 | list_for_each_entry(mod, &modules, list) { |
8244062e RR |
4445 | /* We hold module_mutex: no need for rcu_dereference_sched */ |
4446 | struct mod_kallsyms *kallsyms = mod->kallsyms; | |
4447 | ||
0d21b0e3 RR |
4448 | if (mod->state == MODULE_STATE_UNFORMED) |
4449 | continue; | |
8244062e | 4450 | for (i = 0; i < kallsyms->num_symtab; i++) { |
93d77e7f | 4451 | const Elf_Sym *sym = &kallsyms->symtab[i]; |
9f2d1e68 | 4452 | |
93d77e7f | 4453 | if (sym->st_shndx == SHN_UNDEF) |
9f2d1e68 JY |
4454 | continue; |
4455 | ||
2d25bc55 | 4456 | ret = fn(data, kallsyms_symbol_name(kallsyms, i), |
93d77e7f | 4457 | mod, kallsyms_symbol_value(sym)); |
75a66614 | 4458 | if (ret != 0) |
2c0f0f36 | 4459 | goto out; |
75a66614 AK |
4460 | } |
4461 | } | |
2c0f0f36 | 4462 | out: |
013c1667 CH |
4463 | mutex_unlock(&module_mutex); |
4464 | return ret; | |
75a66614 | 4465 | } |
3e355205 | 4466 | #endif /* CONFIG_LIVEPATCH */ |
1da177e4 LT |
4467 | #endif /* CONFIG_KALLSYMS */ |
4468 | ||
cf68fffb ST |
4469 | static void cfi_init(struct module *mod) |
4470 | { | |
4471 | #ifdef CONFIG_CFI_CLANG | |
4472 | initcall_t *init; | |
4473 | exitcall_t *exit; | |
4474 | ||
4475 | rcu_read_lock_sched(); | |
4476 | mod->cfi_check = (cfi_check_fn) | |
4477 | find_kallsyms_symbol_value(mod, "__cfi_check"); | |
4478 | init = (initcall_t *) | |
4479 | find_kallsyms_symbol_value(mod, "__cfi_jt_init_module"); | |
4480 | exit = (exitcall_t *) | |
4481 | find_kallsyms_symbol_value(mod, "__cfi_jt_cleanup_module"); | |
4482 | rcu_read_unlock_sched(); | |
4483 | ||
4484 | /* Fix init/exit functions to point to the CFI jump table */ | |
4485 | if (init) | |
4486 | mod->init = *init; | |
4487 | if (exit) | |
4488 | mod->exit = *exit; | |
4489 | ||
4490 | cfi_module_add(mod, module_addr_min); | |
4491 | #endif | |
4492 | } | |
4493 | ||
4494 | static void cfi_cleanup(struct module *mod) | |
4495 | { | |
4496 | #ifdef CONFIG_CFI_CLANG | |
4497 | cfi_module_remove(mod, module_addr_min); | |
4498 | #endif | |
4499 | } | |
4500 | ||
7fd8329b PM |
4501 | /* Maximum number of characters written by module_flags() */ |
4502 | #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) | |
4503 | ||
4504 | /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */ | |
21aa9280 | 4505 | static char *module_flags(struct module *mod, char *buf) |
fa3ba2e8 FM |
4506 | { |
4507 | int bx = 0; | |
4508 | ||
0d21b0e3 | 4509 | BUG_ON(mod->state == MODULE_STATE_UNFORMED); |
21aa9280 AV |
4510 | if (mod->taints || |
4511 | mod->state == MODULE_STATE_GOING || | |
4512 | mod->state == MODULE_STATE_COMING) { | |
fa3ba2e8 | 4513 | buf[bx++] = '('; |
cca3e707 | 4514 | bx += module_flags_taint(mod, buf + bx); |
21aa9280 AV |
4515 | /* Show a - for module-is-being-unloaded */ |
4516 | if (mod->state == MODULE_STATE_GOING) | |
4517 | buf[bx++] = '-'; | |
4518 | /* Show a + for module-is-being-loaded */ | |
4519 | if (mod->state == MODULE_STATE_COMING) | |
4520 | buf[bx++] = '+'; | |
fa3ba2e8 FM |
4521 | buf[bx++] = ')'; |
4522 | } | |
4523 | buf[bx] = '\0'; | |
4524 | ||
4525 | return buf; | |
4526 | } | |
4527 | ||
3b5d5c6b AD |
4528 | #ifdef CONFIG_PROC_FS |
4529 | /* Called by the /proc file system to return a list of modules. */ | |
4530 | static void *m_start(struct seq_file *m, loff_t *pos) | |
4531 | { | |
4532 | mutex_lock(&module_mutex); | |
4533 | return seq_list_start(&modules, *pos); | |
4534 | } | |
4535 | ||
4536 | static void *m_next(struct seq_file *m, void *p, loff_t *pos) | |
4537 | { | |
4538 | return seq_list_next(p, &modules, pos); | |
4539 | } | |
4540 | ||
4541 | static void m_stop(struct seq_file *m, void *p) | |
4542 | { | |
4543 | mutex_unlock(&module_mutex); | |
4544 | } | |
4545 | ||
1da177e4 LT |
4546 | static int m_show(struct seq_file *m, void *p) |
4547 | { | |
4548 | struct module *mod = list_entry(p, struct module, list); | |
7fd8329b | 4549 | char buf[MODULE_FLAGS_BUF_SIZE]; |
668533dc | 4550 | void *value; |
fa3ba2e8 | 4551 | |
0d21b0e3 RR |
4552 | /* We always ignore unformed modules. */ |
4553 | if (mod->state == MODULE_STATE_UNFORMED) | |
4554 | return 0; | |
4555 | ||
2f0f2a33 | 4556 | seq_printf(m, "%s %u", |
7523e4dc | 4557 | mod->name, mod->init_layout.size + mod->core_layout.size); |
1da177e4 LT |
4558 | print_unload_info(m, mod); |
4559 | ||
4560 | /* Informative for users. */ | |
4561 | seq_printf(m, " %s", | |
6da0b565 IA |
4562 | mod->state == MODULE_STATE_GOING ? "Unloading" : |
4563 | mod->state == MODULE_STATE_COMING ? "Loading" : | |
1da177e4 LT |
4564 | "Live"); |
4565 | /* Used by oprofile and other similar tools. */ | |
668533dc LT |
4566 | value = m->private ? NULL : mod->core_layout.base; |
4567 | seq_printf(m, " 0x%px", value); | |
1da177e4 | 4568 | |
fa3ba2e8 FM |
4569 | /* Taints info */ |
4570 | if (mod->taints) | |
21aa9280 | 4571 | seq_printf(m, " %s", module_flags(mod, buf)); |
fa3ba2e8 | 4572 | |
6da0b565 | 4573 | seq_puts(m, "\n"); |
1da177e4 LT |
4574 | return 0; |
4575 | } | |
4576 | ||
24b9f0d2 SS |
4577 | /* |
4578 | * Format: modulename size refcount deps address | |
4579 | * | |
4580 | * Where refcount is a number or -, and deps is a comma-separated list | |
4581 | * of depends or -. | |
4582 | */ | |
3b5d5c6b | 4583 | static const struct seq_operations modules_op = { |
1da177e4 LT |
4584 | .start = m_start, |
4585 | .next = m_next, | |
4586 | .stop = m_stop, | |
4587 | .show = m_show | |
4588 | }; | |
4589 | ||
516fb7f2 LT |
4590 | /* |
4591 | * This also sets the "private" pointer to non-NULL if the | |
4592 | * kernel pointers should be hidden (so you can just test | |
4593 | * "m->private" to see if you should keep the values private). | |
4594 | * | |
4595 | * We use the same logic as for /proc/kallsyms. | |
4596 | */ | |
3b5d5c6b AD |
4597 | static int modules_open(struct inode *inode, struct file *file) |
4598 | { | |
516fb7f2 LT |
4599 | int err = seq_open(file, &modules_op); |
4600 | ||
4601 | if (!err) { | |
4602 | struct seq_file *m = file->private_data; | |
b25a7c5a | 4603 | m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul; |
516fb7f2 LT |
4604 | } |
4605 | ||
3f553b30 | 4606 | return err; |
3b5d5c6b AD |
4607 | } |
4608 | ||
97a32539 | 4609 | static const struct proc_ops modules_proc_ops = { |
d919b33d | 4610 | .proc_flags = PROC_ENTRY_PERMANENT, |
97a32539 AD |
4611 | .proc_open = modules_open, |
4612 | .proc_read = seq_read, | |
4613 | .proc_lseek = seq_lseek, | |
4614 | .proc_release = seq_release, | |
3b5d5c6b AD |
4615 | }; |
4616 | ||
4617 | static int __init proc_modules_init(void) | |
4618 | { | |
97a32539 | 4619 | proc_create("modules", 0, NULL, &modules_proc_ops); |
3b5d5c6b AD |
4620 | return 0; |
4621 | } | |
4622 | module_init(proc_modules_init); | |
4623 | #endif | |
4624 | ||
1da177e4 LT |
4625 | /* Given an address, look for it in the module exception tables. */ |
4626 | const struct exception_table_entry *search_module_extables(unsigned long addr) | |
4627 | { | |
1da177e4 LT |
4628 | const struct exception_table_entry *e = NULL; |
4629 | struct module *mod; | |
4630 | ||
24da1cbf | 4631 | preempt_disable(); |
5ff22646 PZ |
4632 | mod = __module_address(addr); |
4633 | if (!mod) | |
4634 | goto out; | |
22a8bdeb | 4635 | |
5ff22646 PZ |
4636 | if (!mod->num_exentries) |
4637 | goto out; | |
4638 | ||
4639 | e = search_extable(mod->extable, | |
a94c33dd | 4640 | mod->num_exentries, |
5ff22646 PZ |
4641 | addr); |
4642 | out: | |
24da1cbf | 4643 | preempt_enable(); |
1da177e4 | 4644 | |
5ff22646 PZ |
4645 | /* |
4646 | * Now, if we found one, we are running inside it now, hence | |
4647 | * we cannot unload the module, hence no refcnt needed. | |
4648 | */ | |
1da177e4 LT |
4649 | return e; |
4650 | } | |
4651 | ||
2541743e SS |
4652 | /** |
4653 | * is_module_address() - is this address inside a module? | |
e610499e RR |
4654 | * @addr: the address to check. |
4655 | * | |
4656 | * See is_module_text_address() if you simply want to see if the address | |
4657 | * is code (not data). | |
4d435f9d | 4658 | */ |
e610499e | 4659 | bool is_module_address(unsigned long addr) |
4d435f9d | 4660 | { |
e610499e | 4661 | bool ret; |
4d435f9d | 4662 | |
24da1cbf | 4663 | preempt_disable(); |
e610499e | 4664 | ret = __module_address(addr) != NULL; |
24da1cbf | 4665 | preempt_enable(); |
4d435f9d | 4666 | |
e610499e | 4667 | return ret; |
4d435f9d IM |
4668 | } |
4669 | ||
2541743e SS |
4670 | /** |
4671 | * __module_address() - get the module which contains an address. | |
e610499e RR |
4672 | * @addr: the address. |
4673 | * | |
4674 | * Must be called with preempt disabled or module mutex held so that | |
4675 | * module doesn't get freed during this. | |
4676 | */ | |
714f83d5 | 4677 | struct module *__module_address(unsigned long addr) |
1da177e4 LT |
4678 | { |
4679 | struct module *mod; | |
4680 | ||
3a642e99 RR |
4681 | if (addr < module_addr_min || addr > module_addr_max) |
4682 | return NULL; | |
4683 | ||
0be964be PZ |
4684 | module_assert_mutex_or_preempt(); |
4685 | ||
6c9692e2 | 4686 | mod = mod_find(addr); |
93c2e105 PZ |
4687 | if (mod) { |
4688 | BUG_ON(!within_module(addr, mod)); | |
0d21b0e3 | 4689 | if (mod->state == MODULE_STATE_UNFORMED) |
93c2e105 | 4690 | mod = NULL; |
0d21b0e3 | 4691 | } |
93c2e105 | 4692 | return mod; |
1da177e4 LT |
4693 | } |
4694 | ||
2541743e SS |
4695 | /** |
4696 | * is_module_text_address() - is this address inside module code? | |
e610499e RR |
4697 | * @addr: the address to check. |
4698 | * | |
4699 | * See is_module_address() if you simply want to see if the address is | |
4700 | * anywhere in a module. See kernel_text_address() for testing if an | |
4701 | * address corresponds to kernel or module code. | |
4702 | */ | |
4703 | bool is_module_text_address(unsigned long addr) | |
4704 | { | |
4705 | bool ret; | |
4706 | ||
4707 | preempt_disable(); | |
4708 | ret = __module_text_address(addr) != NULL; | |
4709 | preempt_enable(); | |
4710 | ||
4711 | return ret; | |
4712 | } | |
4713 | ||
2541743e SS |
4714 | /** |
4715 | * __module_text_address() - get the module whose code contains an address. | |
e610499e RR |
4716 | * @addr: the address. |
4717 | * | |
4718 | * Must be called with preempt disabled or module mutex held so that | |
4719 | * module doesn't get freed during this. | |
4720 | */ | |
4721 | struct module *__module_text_address(unsigned long addr) | |
4722 | { | |
4723 | struct module *mod = __module_address(addr); | |
4724 | if (mod) { | |
4725 | /* Make sure it's within the text section. */ | |
7523e4dc RR |
4726 | if (!within(addr, mod->init_layout.base, mod->init_layout.text_size) |
4727 | && !within(addr, mod->core_layout.base, mod->core_layout.text_size)) | |
e610499e RR |
4728 | mod = NULL; |
4729 | } | |
4730 | return mod; | |
4731 | } | |
4732 | ||
1da177e4 LT |
4733 | /* Don't grab lock, we're oopsing. */ |
4734 | void print_modules(void) | |
4735 | { | |
4736 | struct module *mod; | |
7fd8329b | 4737 | char buf[MODULE_FLAGS_BUF_SIZE]; |
1da177e4 | 4738 | |
b231125a | 4739 | printk(KERN_DEFAULT "Modules linked in:"); |
d72b3751 AK |
4740 | /* Most callers should already have preempt disabled, but make sure */ |
4741 | preempt_disable(); | |
0d21b0e3 RR |
4742 | list_for_each_entry_rcu(mod, &modules, list) { |
4743 | if (mod->state == MODULE_STATE_UNFORMED) | |
4744 | continue; | |
27bba4d6 | 4745 | pr_cont(" %s%s", mod->name, module_flags(mod, buf)); |
0d21b0e3 | 4746 | } |
d72b3751 | 4747 | preempt_enable(); |
e14af7ee | 4748 | if (last_unloaded_module[0]) |
27bba4d6 JS |
4749 | pr_cont(" [last unloaded: %s]", last_unloaded_module); |
4750 | pr_cont("\n"); | |
1da177e4 LT |
4751 | } |
4752 | ||
1da177e4 | 4753 | #ifdef CONFIG_MODVERSIONS |
24b9f0d2 SS |
4754 | /* |
4755 | * Generate the signature for all relevant module structures here. | |
4756 | * If these change, we don't want to try to parse the module. | |
4757 | */ | |
8c8ef42a RR |
4758 | void module_layout(struct module *mod, |
4759 | struct modversion_info *ver, | |
4760 | struct kernel_param *kp, | |
4761 | struct kernel_symbol *ks, | |
65498646 | 4762 | struct tracepoint * const *tp) |
8c8ef42a RR |
4763 | { |
4764 | } | |
4765 | EXPORT_SYMBOL(module_layout); | |
1da177e4 | 4766 | #endif |