Commit | Line | Data |
---|---|---|
f71d20e9 | 1 | /* |
1da177e4 | 2 | Copyright (C) 2002 Richard Henderson |
51f3d0f4 | 3 | Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM. |
1da177e4 LT |
4 | |
5 | This program is free software; you can redistribute it and/or modify | |
6 | it under the terms of the GNU General Public License as published by | |
7 | the Free Software Foundation; either version 2 of the License, or | |
8 | (at your option) any later version. | |
9 | ||
10 | This program is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | GNU General Public License for more details. | |
14 | ||
15 | You should have received a copy of the GNU General Public License | |
16 | along with this program; if not, write to the Free Software | |
17 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | */ | |
9984de1a | 19 | #include <linux/export.h> |
1da177e4 | 20 | #include <linux/moduleloader.h> |
af658dca | 21 | #include <linux/trace_events.h> |
1da177e4 | 22 | #include <linux/init.h> |
ae84e324 | 23 | #include <linux/kallsyms.h> |
34e1169d | 24 | #include <linux/file.h> |
3b5d5c6b | 25 | #include <linux/fs.h> |
6d760133 | 26 | #include <linux/sysfs.h> |
9f158333 | 27 | #include <linux/kernel.h> |
1da177e4 LT |
28 | #include <linux/slab.h> |
29 | #include <linux/vmalloc.h> | |
30 | #include <linux/elf.h> | |
3b5d5c6b | 31 | #include <linux/proc_fs.h> |
2e72d51b | 32 | #include <linux/security.h> |
1da177e4 LT |
33 | #include <linux/seq_file.h> |
34 | #include <linux/syscalls.h> | |
35 | #include <linux/fcntl.h> | |
36 | #include <linux/rcupdate.h> | |
c59ede7b | 37 | #include <linux/capability.h> |
1da177e4 LT |
38 | #include <linux/cpu.h> |
39 | #include <linux/moduleparam.h> | |
40 | #include <linux/errno.h> | |
41 | #include <linux/err.h> | |
42 | #include <linux/vermagic.h> | |
43 | #include <linux/notifier.h> | |
f6a57033 | 44 | #include <linux/sched.h> |
1da177e4 | 45 | #include <linux/device.h> |
c988d2b2 | 46 | #include <linux/string.h> |
97d1f15b | 47 | #include <linux/mutex.h> |
d72b3751 | 48 | #include <linux/rculist.h> |
7c0f6ba6 | 49 | #include <linux/uaccess.h> |
1da177e4 | 50 | #include <asm/cacheflush.h> |
eb8cdec4 | 51 | #include <asm/mmu_context.h> |
b817f6fe | 52 | #include <linux/license.h> |
6d762394 | 53 | #include <asm/sections.h> |
97e1c18e | 54 | #include <linux/tracepoint.h> |
90d595fe | 55 | #include <linux/ftrace.h> |
7e545d6e | 56 | #include <linux/livepatch.h> |
22a9d645 | 57 | #include <linux/async.h> |
fbf59bc9 | 58 | #include <linux/percpu.h> |
4f2294b6 | 59 | #include <linux/kmemleak.h> |
bf5438fc | 60 | #include <linux/jump_label.h> |
84e1c6bb | 61 | #include <linux/pfn.h> |
403ed278 | 62 | #include <linux/bsearch.h> |
9d5059c9 | 63 | #include <linux/dynamic_debug.h> |
2f3238ae | 64 | #include <uapi/linux/module.h> |
106a4ee2 | 65 | #include "module-internal.h" |
1da177e4 | 66 | |
7ead8b83 LZ |
67 | #define CREATE_TRACE_POINTS |
68 | #include <trace/events/module.h> | |
69 | ||
1da177e4 LT |
70 | #ifndef ARCH_SHF_SMALL |
71 | #define ARCH_SHF_SMALL 0 | |
72 | #endif | |
73 | ||
84e1c6bb MC |
74 | /* |
75 | * Modules' sections will be aligned on page boundaries | |
76 | * to ensure complete separation of code and data, but | |
77 | * only when CONFIG_DEBUG_SET_MODULE_RONX=y | |
78 | */ | |
79 | #ifdef CONFIG_DEBUG_SET_MODULE_RONX | |
80 | # define debug_align(X) ALIGN(X, PAGE_SIZE) | |
81 | #else | |
82 | # define debug_align(X) (X) | |
83 | #endif | |
84 | ||
1da177e4 LT |
85 | /* If this is set, the section belongs in the init part of the module */ |
86 | #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) | |
87 | ||
75676500 RR |
88 | /* |
89 | * Mutex protects: | |
90 | * 1) List of modules (also safely readable with preempt_disable), | |
91 | * 2) module_use links, | |
92 | * 3) module_addr_min/module_addr_max. | |
e513cc1c | 93 | * (delete and add uses RCU list operations). */ |
c6b37801 TA |
94 | DEFINE_MUTEX(module_mutex); |
95 | EXPORT_SYMBOL_GPL(module_mutex); | |
1da177e4 | 96 | static LIST_HEAD(modules); |
67fc4e0c | 97 | |
6c9692e2 | 98 | #ifdef CONFIG_MODULES_TREE_LOOKUP |
106a4ee2 | 99 | |
93c2e105 PZ |
100 | /* |
101 | * Use a latched RB-tree for __module_address(); this allows us to use | |
102 | * RCU-sched lookups of the address from any context. | |
103 | * | |
6c9692e2 PZ |
104 | * This is conditional on PERF_EVENTS || TRACING because those can really hit |
105 | * __module_address() hard by doing a lot of stack unwinding; potentially from | |
106 | * NMI context. | |
93c2e105 PZ |
107 | */ |
108 | ||
109 | static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n) | |
106a4ee2 | 110 | { |
7523e4dc | 111 | struct module_layout *layout = container_of(n, struct module_layout, mtn.node); |
106a4ee2 | 112 | |
7523e4dc | 113 | return (unsigned long)layout->base; |
93c2e105 PZ |
114 | } |
115 | ||
116 | static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n) | |
117 | { | |
7523e4dc | 118 | struct module_layout *layout = container_of(n, struct module_layout, mtn.node); |
93c2e105 | 119 | |
7523e4dc | 120 | return (unsigned long)layout->size; |
93c2e105 PZ |
121 | } |
122 | ||
123 | static __always_inline bool | |
124 | mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b) | |
125 | { | |
126 | return __mod_tree_val(a) < __mod_tree_val(b); | |
127 | } | |
128 | ||
129 | static __always_inline int | |
130 | mod_tree_comp(void *key, struct latch_tree_node *n) | |
131 | { | |
132 | unsigned long val = (unsigned long)key; | |
133 | unsigned long start, end; | |
134 | ||
135 | start = __mod_tree_val(n); | |
136 | if (val < start) | |
137 | return -1; | |
138 | ||
139 | end = start + __mod_tree_size(n); | |
140 | if (val >= end) | |
141 | return 1; | |
106a4ee2 | 142 | |
106a4ee2 RR |
143 | return 0; |
144 | } | |
145 | ||
93c2e105 PZ |
146 | static const struct latch_tree_ops mod_tree_ops = { |
147 | .less = mod_tree_less, | |
148 | .comp = mod_tree_comp, | |
149 | }; | |
150 | ||
4f666546 PZ |
151 | static struct mod_tree_root { |
152 | struct latch_tree_root root; | |
153 | unsigned long addr_min; | |
154 | unsigned long addr_max; | |
155 | } mod_tree __cacheline_aligned = { | |
156 | .addr_min = -1UL, | |
106a4ee2 | 157 | }; |
106a4ee2 | 158 | |
4f666546 PZ |
159 | #define module_addr_min mod_tree.addr_min |
160 | #define module_addr_max mod_tree.addr_max | |
161 | ||
162 | static noinline void __mod_tree_insert(struct mod_tree_node *node) | |
163 | { | |
164 | latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops); | |
165 | } | |
166 | ||
167 | static void __mod_tree_remove(struct mod_tree_node *node) | |
168 | { | |
169 | latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops); | |
170 | } | |
93c2e105 PZ |
171 | |
172 | /* | |
173 | * These modifications: insert, remove_init and remove; are serialized by the | |
174 | * module_mutex. | |
175 | */ | |
176 | static void mod_tree_insert(struct module *mod) | |
177 | { | |
7523e4dc RR |
178 | mod->core_layout.mtn.mod = mod; |
179 | mod->init_layout.mtn.mod = mod; | |
93c2e105 | 180 | |
7523e4dc RR |
181 | __mod_tree_insert(&mod->core_layout.mtn); |
182 | if (mod->init_layout.size) | |
183 | __mod_tree_insert(&mod->init_layout.mtn); | |
93c2e105 PZ |
184 | } |
185 | ||
186 | static void mod_tree_remove_init(struct module *mod) | |
187 | { | |
7523e4dc RR |
188 | if (mod->init_layout.size) |
189 | __mod_tree_remove(&mod->init_layout.mtn); | |
93c2e105 PZ |
190 | } |
191 | ||
192 | static void mod_tree_remove(struct module *mod) | |
193 | { | |
7523e4dc | 194 | __mod_tree_remove(&mod->core_layout.mtn); |
93c2e105 PZ |
195 | mod_tree_remove_init(mod); |
196 | } | |
197 | ||
6c9692e2 | 198 | static struct module *mod_find(unsigned long addr) |
93c2e105 PZ |
199 | { |
200 | struct latch_tree_node *ltn; | |
201 | ||
4f666546 | 202 | ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops); |
93c2e105 PZ |
203 | if (!ltn) |
204 | return NULL; | |
205 | ||
206 | return container_of(ltn, struct mod_tree_node, node)->mod; | |
207 | } | |
208 | ||
6c9692e2 PZ |
209 | #else /* MODULES_TREE_LOOKUP */ |
210 | ||
4f666546 PZ |
211 | static unsigned long module_addr_min = -1UL, module_addr_max = 0; |
212 | ||
6c9692e2 PZ |
213 | static void mod_tree_insert(struct module *mod) { } |
214 | static void mod_tree_remove_init(struct module *mod) { } | |
215 | static void mod_tree_remove(struct module *mod) { } | |
216 | ||
217 | static struct module *mod_find(unsigned long addr) | |
218 | { | |
219 | struct module *mod; | |
220 | ||
221 | list_for_each_entry_rcu(mod, &modules, list) { | |
222 | if (within_module(addr, mod)) | |
223 | return mod; | |
224 | } | |
225 | ||
226 | return NULL; | |
227 | } | |
228 | ||
229 | #endif /* MODULES_TREE_LOOKUP */ | |
230 | ||
4f666546 PZ |
231 | /* |
232 | * Bounds of module text, for speeding up __module_address. | |
233 | * Protected by module_mutex. | |
234 | */ | |
235 | static void __mod_update_bounds(void *base, unsigned int size) | |
236 | { | |
237 | unsigned long min = (unsigned long)base; | |
238 | unsigned long max = min + size; | |
239 | ||
240 | if (min < module_addr_min) | |
241 | module_addr_min = min; | |
242 | if (max > module_addr_max) | |
243 | module_addr_max = max; | |
244 | } | |
245 | ||
246 | static void mod_update_bounds(struct module *mod) | |
247 | { | |
7523e4dc RR |
248 | __mod_update_bounds(mod->core_layout.base, mod->core_layout.size); |
249 | if (mod->init_layout.size) | |
250 | __mod_update_bounds(mod->init_layout.base, mod->init_layout.size); | |
4f666546 PZ |
251 | } |
252 | ||
67fc4e0c JW |
253 | #ifdef CONFIG_KGDB_KDB |
254 | struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ | |
255 | #endif /* CONFIG_KGDB_KDB */ | |
256 | ||
0be964be PZ |
257 | static void module_assert_mutex(void) |
258 | { | |
259 | lockdep_assert_held(&module_mutex); | |
260 | } | |
261 | ||
262 | static void module_assert_mutex_or_preempt(void) | |
263 | { | |
264 | #ifdef CONFIG_LOCKDEP | |
265 | if (unlikely(!debug_locks)) | |
266 | return; | |
267 | ||
9502514f | 268 | WARN_ON_ONCE(!rcu_read_lock_sched_held() && |
0be964be PZ |
269 | !lockdep_is_held(&module_mutex)); |
270 | #endif | |
271 | } | |
272 | ||
6727bb9c LR |
273 | static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE); |
274 | #ifndef CONFIG_MODULE_SIG_FORCE | |
106a4ee2 RR |
275 | module_param(sig_enforce, bool_enable_only, 0644); |
276 | #endif /* !CONFIG_MODULE_SIG_FORCE */ | |
1da177e4 | 277 | |
19e4529e SR |
278 | /* Block module loading/unloading? */ |
279 | int modules_disabled = 0; | |
02608bef | 280 | core_param(nomodule, modules_disabled, bint, 0); |
19e4529e | 281 | |
c9a3ba55 RR |
282 | /* Waiting for a module to finish initializing? */ |
283 | static DECLARE_WAIT_QUEUE_HEAD(module_wq); | |
284 | ||
e041c683 | 285 | static BLOCKING_NOTIFIER_HEAD(module_notify_list); |
1da177e4 | 286 | |
6da0b565 | 287 | int register_module_notifier(struct notifier_block *nb) |
1da177e4 | 288 | { |
e041c683 | 289 | return blocking_notifier_chain_register(&module_notify_list, nb); |
1da177e4 LT |
290 | } |
291 | EXPORT_SYMBOL(register_module_notifier); | |
292 | ||
6da0b565 | 293 | int unregister_module_notifier(struct notifier_block *nb) |
1da177e4 | 294 | { |
e041c683 | 295 | return blocking_notifier_chain_unregister(&module_notify_list, nb); |
1da177e4 LT |
296 | } |
297 | EXPORT_SYMBOL(unregister_module_notifier); | |
298 | ||
eded41c1 RR |
299 | struct load_info { |
300 | Elf_Ehdr *hdr; | |
301 | unsigned long len; | |
302 | Elf_Shdr *sechdrs; | |
6526c534 | 303 | char *secstrings, *strtab; |
d913188c | 304 | unsigned long symoffs, stroffs; |
811d66a0 RR |
305 | struct _ddebug *debug; |
306 | unsigned int num_debug; | |
106a4ee2 | 307 | bool sig_ok; |
8244062e RR |
308 | #ifdef CONFIG_KALLSYMS |
309 | unsigned long mod_kallsyms_init_off; | |
310 | #endif | |
eded41c1 RR |
311 | struct { |
312 | unsigned int sym, str, mod, vers, info, pcpu; | |
313 | } index; | |
314 | }; | |
315 | ||
71d9f507 MB |
316 | /* |
317 | * We require a truly strong try_module_get(): 0 means success. | |
318 | * Otherwise an error is returned due to ongoing or failed | |
319 | * initialization etc. | |
320 | */ | |
1da177e4 LT |
321 | static inline int strong_try_module_get(struct module *mod) |
322 | { | |
0d21b0e3 | 323 | BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED); |
1da177e4 | 324 | if (mod && mod->state == MODULE_STATE_COMING) |
c9a3ba55 RR |
325 | return -EBUSY; |
326 | if (try_module_get(mod)) | |
1da177e4 | 327 | return 0; |
c9a3ba55 RR |
328 | else |
329 | return -ENOENT; | |
1da177e4 LT |
330 | } |
331 | ||
373d4d09 RR |
332 | static inline void add_taint_module(struct module *mod, unsigned flag, |
333 | enum lockdep_ok lockdep_ok) | |
fa3ba2e8 | 334 | { |
373d4d09 | 335 | add_taint(flag, lockdep_ok); |
7fd8329b | 336 | set_bit(flag, &mod->taints); |
fa3ba2e8 FM |
337 | } |
338 | ||
02a3e59a RD |
339 | /* |
340 | * A thread that wants to hold a reference to a module only while it | |
341 | * is running can call this to safely exit. nfsd and lockd use this. | |
1da177e4 | 342 | */ |
bf262dce | 343 | void __noreturn __module_put_and_exit(struct module *mod, long code) |
1da177e4 LT |
344 | { |
345 | module_put(mod); | |
346 | do_exit(code); | |
347 | } | |
348 | EXPORT_SYMBOL(__module_put_and_exit); | |
22a8bdeb | 349 | |
1da177e4 | 350 | /* Find a module section: 0 means not found. */ |
49668688 | 351 | static unsigned int find_sec(const struct load_info *info, const char *name) |
1da177e4 LT |
352 | { |
353 | unsigned int i; | |
354 | ||
49668688 RR |
355 | for (i = 1; i < info->hdr->e_shnum; i++) { |
356 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
1da177e4 | 357 | /* Alloc bit cleared means "ignore it." */ |
49668688 RR |
358 | if ((shdr->sh_flags & SHF_ALLOC) |
359 | && strcmp(info->secstrings + shdr->sh_name, name) == 0) | |
1da177e4 | 360 | return i; |
49668688 | 361 | } |
1da177e4 LT |
362 | return 0; |
363 | } | |
364 | ||
5e458cc0 | 365 | /* Find a module section, or NULL. */ |
49668688 | 366 | static void *section_addr(const struct load_info *info, const char *name) |
5e458cc0 RR |
367 | { |
368 | /* Section 0 has sh_addr 0. */ | |
49668688 | 369 | return (void *)info->sechdrs[find_sec(info, name)].sh_addr; |
5e458cc0 RR |
370 | } |
371 | ||
372 | /* Find a module section, or NULL. Fill in number of "objects" in section. */ | |
49668688 | 373 | static void *section_objs(const struct load_info *info, |
5e458cc0 RR |
374 | const char *name, |
375 | size_t object_size, | |
376 | unsigned int *num) | |
377 | { | |
49668688 | 378 | unsigned int sec = find_sec(info, name); |
5e458cc0 RR |
379 | |
380 | /* Section 0 has sh_addr 0 and sh_size 0. */ | |
49668688 RR |
381 | *num = info->sechdrs[sec].sh_size / object_size; |
382 | return (void *)info->sechdrs[sec].sh_addr; | |
5e458cc0 RR |
383 | } |
384 | ||
1da177e4 LT |
385 | /* Provided by the linker */ |
386 | extern const struct kernel_symbol __start___ksymtab[]; | |
387 | extern const struct kernel_symbol __stop___ksymtab[]; | |
388 | extern const struct kernel_symbol __start___ksymtab_gpl[]; | |
389 | extern const struct kernel_symbol __stop___ksymtab_gpl[]; | |
9f28bb7e GKH |
390 | extern const struct kernel_symbol __start___ksymtab_gpl_future[]; |
391 | extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; | |
1da177e4 LT |
392 | extern const unsigned long __start___kcrctab[]; |
393 | extern const unsigned long __start___kcrctab_gpl[]; | |
9f28bb7e | 394 | extern const unsigned long __start___kcrctab_gpl_future[]; |
f7f5b675 DV |
395 | #ifdef CONFIG_UNUSED_SYMBOLS |
396 | extern const struct kernel_symbol __start___ksymtab_unused[]; | |
397 | extern const struct kernel_symbol __stop___ksymtab_unused[]; | |
398 | extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; | |
399 | extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; | |
f71d20e9 AV |
400 | extern const unsigned long __start___kcrctab_unused[]; |
401 | extern const unsigned long __start___kcrctab_unused_gpl[]; | |
f7f5b675 | 402 | #endif |
1da177e4 LT |
403 | |
404 | #ifndef CONFIG_MODVERSIONS | |
405 | #define symversion(base, idx) NULL | |
406 | #else | |
f83ca9fe | 407 | #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL) |
1da177e4 LT |
408 | #endif |
409 | ||
dafd0940 RR |
410 | static bool each_symbol_in_section(const struct symsearch *arr, |
411 | unsigned int arrsize, | |
412 | struct module *owner, | |
413 | bool (*fn)(const struct symsearch *syms, | |
414 | struct module *owner, | |
de4d8d53 | 415 | void *data), |
dafd0940 | 416 | void *data) |
ad9546c9 | 417 | { |
de4d8d53 | 418 | unsigned int j; |
ad9546c9 | 419 | |
dafd0940 | 420 | for (j = 0; j < arrsize; j++) { |
de4d8d53 RR |
421 | if (fn(&arr[j], owner, data)) |
422 | return true; | |
f71d20e9 | 423 | } |
dafd0940 RR |
424 | |
425 | return false; | |
ad9546c9 RR |
426 | } |
427 | ||
dafd0940 | 428 | /* Returns true as soon as fn returns true, otherwise false. */ |
de4d8d53 RR |
429 | bool each_symbol_section(bool (*fn)(const struct symsearch *arr, |
430 | struct module *owner, | |
431 | void *data), | |
432 | void *data) | |
ad9546c9 RR |
433 | { |
434 | struct module *mod; | |
44032e63 | 435 | static const struct symsearch arr[] = { |
ad9546c9 | 436 | { __start___ksymtab, __stop___ksymtab, __start___kcrctab, |
dafd0940 | 437 | NOT_GPL_ONLY, false }, |
ad9546c9 | 438 | { __start___ksymtab_gpl, __stop___ksymtab_gpl, |
dafd0940 RR |
439 | __start___kcrctab_gpl, |
440 | GPL_ONLY, false }, | |
ad9546c9 | 441 | { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future, |
dafd0940 RR |
442 | __start___kcrctab_gpl_future, |
443 | WILL_BE_GPL_ONLY, false }, | |
f7f5b675 | 444 | #ifdef CONFIG_UNUSED_SYMBOLS |
ad9546c9 | 445 | { __start___ksymtab_unused, __stop___ksymtab_unused, |
dafd0940 RR |
446 | __start___kcrctab_unused, |
447 | NOT_GPL_ONLY, true }, | |
ad9546c9 | 448 | { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl, |
dafd0940 RR |
449 | __start___kcrctab_unused_gpl, |
450 | GPL_ONLY, true }, | |
f7f5b675 | 451 | #endif |
ad9546c9 | 452 | }; |
f71d20e9 | 453 | |
0be964be PZ |
454 | module_assert_mutex_or_preempt(); |
455 | ||
dafd0940 RR |
456 | if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data)) |
457 | return true; | |
f71d20e9 | 458 | |
d72b3751 | 459 | list_for_each_entry_rcu(mod, &modules, list) { |
ad9546c9 RR |
460 | struct symsearch arr[] = { |
461 | { mod->syms, mod->syms + mod->num_syms, mod->crcs, | |
dafd0940 | 462 | NOT_GPL_ONLY, false }, |
ad9546c9 | 463 | { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, |
dafd0940 RR |
464 | mod->gpl_crcs, |
465 | GPL_ONLY, false }, | |
ad9546c9 RR |
466 | { mod->gpl_future_syms, |
467 | mod->gpl_future_syms + mod->num_gpl_future_syms, | |
dafd0940 RR |
468 | mod->gpl_future_crcs, |
469 | WILL_BE_GPL_ONLY, false }, | |
f7f5b675 | 470 | #ifdef CONFIG_UNUSED_SYMBOLS |
ad9546c9 RR |
471 | { mod->unused_syms, |
472 | mod->unused_syms + mod->num_unused_syms, | |
dafd0940 RR |
473 | mod->unused_crcs, |
474 | NOT_GPL_ONLY, true }, | |
ad9546c9 RR |
475 | { mod->unused_gpl_syms, |
476 | mod->unused_gpl_syms + mod->num_unused_gpl_syms, | |
dafd0940 RR |
477 | mod->unused_gpl_crcs, |
478 | GPL_ONLY, true }, | |
f7f5b675 | 479 | #endif |
ad9546c9 RR |
480 | }; |
481 | ||
0d21b0e3 RR |
482 | if (mod->state == MODULE_STATE_UNFORMED) |
483 | continue; | |
484 | ||
dafd0940 RR |
485 | if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data)) |
486 | return true; | |
487 | } | |
488 | return false; | |
489 | } | |
de4d8d53 | 490 | EXPORT_SYMBOL_GPL(each_symbol_section); |
dafd0940 RR |
491 | |
492 | struct find_symbol_arg { | |
493 | /* Input */ | |
494 | const char *name; | |
495 | bool gplok; | |
496 | bool warn; | |
497 | ||
498 | /* Output */ | |
499 | struct module *owner; | |
500 | const unsigned long *crc; | |
414fd31b | 501 | const struct kernel_symbol *sym; |
dafd0940 RR |
502 | }; |
503 | ||
de4d8d53 RR |
504 | static bool check_symbol(const struct symsearch *syms, |
505 | struct module *owner, | |
506 | unsigned int symnum, void *data) | |
dafd0940 RR |
507 | { |
508 | struct find_symbol_arg *fsa = data; | |
509 | ||
dafd0940 RR |
510 | if (!fsa->gplok) { |
511 | if (syms->licence == GPL_ONLY) | |
512 | return false; | |
513 | if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) { | |
bddb12b3 AM |
514 | pr_warn("Symbol %s is being used by a non-GPL module, " |
515 | "which will not be allowed in the future\n", | |
516 | fsa->name); | |
9f28bb7e | 517 | } |
1da177e4 | 518 | } |
ad9546c9 | 519 | |
f7f5b675 | 520 | #ifdef CONFIG_UNUSED_SYMBOLS |
dafd0940 | 521 | if (syms->unused && fsa->warn) { |
bddb12b3 AM |
522 | pr_warn("Symbol %s is marked as UNUSED, however this module is " |
523 | "using it.\n", fsa->name); | |
524 | pr_warn("This symbol will go away in the future.\n"); | |
7b63c3ab YG |
525 | pr_warn("Please evaluate if this is the right api to use and " |
526 | "if it really is, submit a report to the linux kernel " | |
527 | "mailing list together with submitting your code for " | |
bddb12b3 | 528 | "inclusion.\n"); |
dafd0940 | 529 | } |
f7f5b675 | 530 | #endif |
dafd0940 RR |
531 | |
532 | fsa->owner = owner; | |
533 | fsa->crc = symversion(syms->crcs, symnum); | |
414fd31b | 534 | fsa->sym = &syms->start[symnum]; |
dafd0940 RR |
535 | return true; |
536 | } | |
537 | ||
403ed278 AIB |
538 | static int cmp_name(const void *va, const void *vb) |
539 | { | |
540 | const char *a; | |
541 | const struct kernel_symbol *b; | |
542 | a = va; b = vb; | |
543 | return strcmp(a, b->name); | |
544 | } | |
545 | ||
de4d8d53 RR |
546 | static bool find_symbol_in_section(const struct symsearch *syms, |
547 | struct module *owner, | |
548 | void *data) | |
549 | { | |
550 | struct find_symbol_arg *fsa = data; | |
403ed278 AIB |
551 | struct kernel_symbol *sym; |
552 | ||
553 | sym = bsearch(fsa->name, syms->start, syms->stop - syms->start, | |
554 | sizeof(struct kernel_symbol), cmp_name); | |
555 | ||
556 | if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data)) | |
557 | return true; | |
de4d8d53 | 558 | |
de4d8d53 RR |
559 | return false; |
560 | } | |
561 | ||
414fd31b | 562 | /* Find a symbol and return it, along with, (optional) crc and |
75676500 | 563 | * (optional) module which owns it. Needs preempt disabled or module_mutex. */ |
c6b37801 TA |
564 | const struct kernel_symbol *find_symbol(const char *name, |
565 | struct module **owner, | |
566 | const unsigned long **crc, | |
567 | bool gplok, | |
568 | bool warn) | |
dafd0940 RR |
569 | { |
570 | struct find_symbol_arg fsa; | |
571 | ||
572 | fsa.name = name; | |
573 | fsa.gplok = gplok; | |
574 | fsa.warn = warn; | |
575 | ||
de4d8d53 | 576 | if (each_symbol_section(find_symbol_in_section, &fsa)) { |
dafd0940 RR |
577 | if (owner) |
578 | *owner = fsa.owner; | |
579 | if (crc) | |
580 | *crc = fsa.crc; | |
414fd31b | 581 | return fsa.sym; |
dafd0940 RR |
582 | } |
583 | ||
5e124169 | 584 | pr_debug("Failed to find symbol %s\n", name); |
414fd31b | 585 | return NULL; |
1da177e4 | 586 | } |
c6b37801 | 587 | EXPORT_SYMBOL_GPL(find_symbol); |
1da177e4 | 588 | |
fe0d34d2 RR |
589 | /* |
590 | * Search for module by name: must hold module_mutex (or preempt disabled | |
591 | * for read-only access). | |
592 | */ | |
4f6de4d5 | 593 | static struct module *find_module_all(const char *name, size_t len, |
0d21b0e3 | 594 | bool even_unformed) |
1da177e4 LT |
595 | { |
596 | struct module *mod; | |
597 | ||
fe0d34d2 | 598 | module_assert_mutex_or_preempt(); |
0be964be | 599 | |
1da177e4 | 600 | list_for_each_entry(mod, &modules, list) { |
0d21b0e3 RR |
601 | if (!even_unformed && mod->state == MODULE_STATE_UNFORMED) |
602 | continue; | |
4f6de4d5 | 603 | if (strlen(mod->name) == len && !memcmp(mod->name, name, len)) |
1da177e4 LT |
604 | return mod; |
605 | } | |
606 | return NULL; | |
607 | } | |
0d21b0e3 RR |
608 | |
609 | struct module *find_module(const char *name) | |
610 | { | |
fe0d34d2 | 611 | module_assert_mutex(); |
4f6de4d5 | 612 | return find_module_all(name, strlen(name), false); |
0d21b0e3 | 613 | } |
c6b37801 | 614 | EXPORT_SYMBOL_GPL(find_module); |
1da177e4 LT |
615 | |
616 | #ifdef CONFIG_SMP | |
fbf59bc9 | 617 | |
259354de | 618 | static inline void __percpu *mod_percpu(struct module *mod) |
fbf59bc9 | 619 | { |
259354de TH |
620 | return mod->percpu; |
621 | } | |
fbf59bc9 | 622 | |
9eb76d77 | 623 | static int percpu_modalloc(struct module *mod, struct load_info *info) |
259354de | 624 | { |
9eb76d77 RR |
625 | Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu]; |
626 | unsigned long align = pcpusec->sh_addralign; | |
627 | ||
628 | if (!pcpusec->sh_size) | |
629 | return 0; | |
630 | ||
fbf59bc9 | 631 | if (align > PAGE_SIZE) { |
bddb12b3 AM |
632 | pr_warn("%s: per-cpu alignment %li > %li\n", |
633 | mod->name, align, PAGE_SIZE); | |
fbf59bc9 TH |
634 | align = PAGE_SIZE; |
635 | } | |
636 | ||
9eb76d77 | 637 | mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align); |
259354de | 638 | if (!mod->percpu) { |
bddb12b3 AM |
639 | pr_warn("%s: Could not allocate %lu bytes percpu data\n", |
640 | mod->name, (unsigned long)pcpusec->sh_size); | |
259354de TH |
641 | return -ENOMEM; |
642 | } | |
9eb76d77 | 643 | mod->percpu_size = pcpusec->sh_size; |
259354de | 644 | return 0; |
fbf59bc9 TH |
645 | } |
646 | ||
259354de | 647 | static void percpu_modfree(struct module *mod) |
fbf59bc9 | 648 | { |
259354de | 649 | free_percpu(mod->percpu); |
fbf59bc9 TH |
650 | } |
651 | ||
49668688 | 652 | static unsigned int find_pcpusec(struct load_info *info) |
6b588c18 | 653 | { |
49668688 | 654 | return find_sec(info, ".data..percpu"); |
6b588c18 TH |
655 | } |
656 | ||
259354de TH |
657 | static void percpu_modcopy(struct module *mod, |
658 | const void *from, unsigned long size) | |
6b588c18 TH |
659 | { |
660 | int cpu; | |
661 | ||
662 | for_each_possible_cpu(cpu) | |
259354de | 663 | memcpy(per_cpu_ptr(mod->percpu, cpu), from, size); |
6b588c18 TH |
664 | } |
665 | ||
10fad5e4 TH |
666 | /** |
667 | * is_module_percpu_address - test whether address is from module static percpu | |
668 | * @addr: address to test | |
669 | * | |
670 | * Test whether @addr belongs to module static percpu area. | |
671 | * | |
672 | * RETURNS: | |
673 | * %true if @addr is from module static percpu area | |
674 | */ | |
675 | bool is_module_percpu_address(unsigned long addr) | |
676 | { | |
677 | struct module *mod; | |
678 | unsigned int cpu; | |
679 | ||
680 | preempt_disable(); | |
681 | ||
682 | list_for_each_entry_rcu(mod, &modules, list) { | |
0d21b0e3 RR |
683 | if (mod->state == MODULE_STATE_UNFORMED) |
684 | continue; | |
10fad5e4 TH |
685 | if (!mod->percpu_size) |
686 | continue; | |
687 | for_each_possible_cpu(cpu) { | |
688 | void *start = per_cpu_ptr(mod->percpu, cpu); | |
689 | ||
690 | if ((void *)addr >= start && | |
691 | (void *)addr < start + mod->percpu_size) { | |
692 | preempt_enable(); | |
693 | return true; | |
694 | } | |
695 | } | |
696 | } | |
697 | ||
698 | preempt_enable(); | |
699 | return false; | |
6b588c18 TH |
700 | } |
701 | ||
1da177e4 | 702 | #else /* ... !CONFIG_SMP */ |
6b588c18 | 703 | |
259354de | 704 | static inline void __percpu *mod_percpu(struct module *mod) |
1da177e4 LT |
705 | { |
706 | return NULL; | |
707 | } | |
9eb76d77 | 708 | static int percpu_modalloc(struct module *mod, struct load_info *info) |
259354de | 709 | { |
9eb76d77 RR |
710 | /* UP modules shouldn't have this section: ENOMEM isn't quite right */ |
711 | if (info->sechdrs[info->index.pcpu].sh_size != 0) | |
712 | return -ENOMEM; | |
713 | return 0; | |
259354de TH |
714 | } |
715 | static inline void percpu_modfree(struct module *mod) | |
1da177e4 | 716 | { |
1da177e4 | 717 | } |
49668688 | 718 | static unsigned int find_pcpusec(struct load_info *info) |
1da177e4 LT |
719 | { |
720 | return 0; | |
721 | } | |
259354de TH |
722 | static inline void percpu_modcopy(struct module *mod, |
723 | const void *from, unsigned long size) | |
1da177e4 LT |
724 | { |
725 | /* pcpusec should be 0, and size of that section should be 0. */ | |
726 | BUG_ON(size != 0); | |
727 | } | |
10fad5e4 TH |
728 | bool is_module_percpu_address(unsigned long addr) |
729 | { | |
730 | return false; | |
731 | } | |
6b588c18 | 732 | |
1da177e4 LT |
733 | #endif /* CONFIG_SMP */ |
734 | ||
c988d2b2 MD |
735 | #define MODINFO_ATTR(field) \ |
736 | static void setup_modinfo_##field(struct module *mod, const char *s) \ | |
737 | { \ | |
738 | mod->field = kstrdup(s, GFP_KERNEL); \ | |
739 | } \ | |
740 | static ssize_t show_modinfo_##field(struct module_attribute *mattr, \ | |
4befb026 | 741 | struct module_kobject *mk, char *buffer) \ |
c988d2b2 | 742 | { \ |
cc56ded3 | 743 | return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \ |
c988d2b2 MD |
744 | } \ |
745 | static int modinfo_##field##_exists(struct module *mod) \ | |
746 | { \ | |
747 | return mod->field != NULL; \ | |
748 | } \ | |
749 | static void free_modinfo_##field(struct module *mod) \ | |
750 | { \ | |
22a8bdeb DW |
751 | kfree(mod->field); \ |
752 | mod->field = NULL; \ | |
c988d2b2 MD |
753 | } \ |
754 | static struct module_attribute modinfo_##field = { \ | |
7b595756 | 755 | .attr = { .name = __stringify(field), .mode = 0444 }, \ |
c988d2b2 MD |
756 | .show = show_modinfo_##field, \ |
757 | .setup = setup_modinfo_##field, \ | |
758 | .test = modinfo_##field##_exists, \ | |
759 | .free = free_modinfo_##field, \ | |
760 | }; | |
761 | ||
762 | MODINFO_ATTR(version); | |
763 | MODINFO_ATTR(srcversion); | |
764 | ||
e14af7ee AV |
765 | static char last_unloaded_module[MODULE_NAME_LEN+1]; |
766 | ||
03e88ae1 | 767 | #ifdef CONFIG_MODULE_UNLOAD |
eb0c5377 SR |
768 | |
769 | EXPORT_TRACEPOINT_SYMBOL(module_get); | |
770 | ||
e513cc1c MH |
771 | /* MODULE_REF_BASE is the base reference count by kmodule loader. */ |
772 | #define MODULE_REF_BASE 1 | |
773 | ||
1da177e4 | 774 | /* Init the unload section of the module. */ |
9f85a4bb | 775 | static int module_unload_init(struct module *mod) |
1da177e4 | 776 | { |
e513cc1c MH |
777 | /* |
778 | * Initialize reference counter to MODULE_REF_BASE. | |
779 | * refcnt == 0 means module is going. | |
780 | */ | |
781 | atomic_set(&mod->refcnt, MODULE_REF_BASE); | |
9f85a4bb | 782 | |
2c02dfe7 LT |
783 | INIT_LIST_HEAD(&mod->source_list); |
784 | INIT_LIST_HEAD(&mod->target_list); | |
e1783a24 | 785 | |
1da177e4 | 786 | /* Hold reference count during initialization. */ |
e513cc1c | 787 | atomic_inc(&mod->refcnt); |
9f85a4bb RR |
788 | |
789 | return 0; | |
1da177e4 LT |
790 | } |
791 | ||
1da177e4 LT |
792 | /* Does a already use b? */ |
793 | static int already_uses(struct module *a, struct module *b) | |
794 | { | |
795 | struct module_use *use; | |
796 | ||
2c02dfe7 LT |
797 | list_for_each_entry(use, &b->source_list, source_list) { |
798 | if (use->source == a) { | |
5e124169 | 799 | pr_debug("%s uses %s!\n", a->name, b->name); |
1da177e4 LT |
800 | return 1; |
801 | } | |
802 | } | |
5e124169 | 803 | pr_debug("%s does not use %s!\n", a->name, b->name); |
1da177e4 LT |
804 | return 0; |
805 | } | |
806 | ||
2c02dfe7 LT |
807 | /* |
808 | * Module a uses b | |
809 | * - we add 'a' as a "source", 'b' as a "target" of module use | |
810 | * - the module_use is added to the list of 'b' sources (so | |
811 | * 'b' can walk the list to see who sourced them), and of 'a' | |
812 | * targets (so 'a' can see what modules it targets). | |
813 | */ | |
814 | static int add_module_usage(struct module *a, struct module *b) | |
815 | { | |
2c02dfe7 LT |
816 | struct module_use *use; |
817 | ||
5e124169 | 818 | pr_debug("Allocating new usage for %s.\n", a->name); |
2c02dfe7 LT |
819 | use = kmalloc(sizeof(*use), GFP_ATOMIC); |
820 | if (!use) { | |
bddb12b3 | 821 | pr_warn("%s: out of memory loading\n", a->name); |
2c02dfe7 LT |
822 | return -ENOMEM; |
823 | } | |
824 | ||
825 | use->source = a; | |
826 | use->target = b; | |
827 | list_add(&use->source_list, &b->source_list); | |
828 | list_add(&use->target_list, &a->target_list); | |
2c02dfe7 LT |
829 | return 0; |
830 | } | |
831 | ||
75676500 | 832 | /* Module a uses b: caller needs module_mutex() */ |
9bea7f23 | 833 | int ref_module(struct module *a, struct module *b) |
1da177e4 | 834 | { |
c8e21ced | 835 | int err; |
270a6c4c | 836 | |
9bea7f23 | 837 | if (b == NULL || already_uses(a, b)) |
218ce735 | 838 | return 0; |
218ce735 | 839 | |
9bea7f23 RR |
840 | /* If module isn't available, we fail. */ |
841 | err = strong_try_module_get(b); | |
c9a3ba55 | 842 | if (err) |
9bea7f23 | 843 | return err; |
1da177e4 | 844 | |
2c02dfe7 LT |
845 | err = add_module_usage(a, b); |
846 | if (err) { | |
1da177e4 | 847 | module_put(b); |
9bea7f23 | 848 | return err; |
1da177e4 | 849 | } |
9bea7f23 | 850 | return 0; |
1da177e4 | 851 | } |
9bea7f23 | 852 | EXPORT_SYMBOL_GPL(ref_module); |
1da177e4 LT |
853 | |
854 | /* Clear the unload stuff of the module. */ | |
855 | static void module_unload_free(struct module *mod) | |
856 | { | |
2c02dfe7 | 857 | struct module_use *use, *tmp; |
1da177e4 | 858 | |
75676500 | 859 | mutex_lock(&module_mutex); |
2c02dfe7 LT |
860 | list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) { |
861 | struct module *i = use->target; | |
5e124169 | 862 | pr_debug("%s unusing %s\n", mod->name, i->name); |
2c02dfe7 LT |
863 | module_put(i); |
864 | list_del(&use->source_list); | |
865 | list_del(&use->target_list); | |
866 | kfree(use); | |
1da177e4 | 867 | } |
75676500 | 868 | mutex_unlock(&module_mutex); |
1da177e4 LT |
869 | } |
870 | ||
871 | #ifdef CONFIG_MODULE_FORCE_UNLOAD | |
fb169793 | 872 | static inline int try_force_unload(unsigned int flags) |
1da177e4 LT |
873 | { |
874 | int ret = (flags & O_TRUNC); | |
875 | if (ret) | |
373d4d09 | 876 | add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE); |
1da177e4 LT |
877 | return ret; |
878 | } | |
879 | #else | |
fb169793 | 880 | static inline int try_force_unload(unsigned int flags) |
1da177e4 LT |
881 | { |
882 | return 0; | |
883 | } | |
884 | #endif /* CONFIG_MODULE_FORCE_UNLOAD */ | |
885 | ||
e513cc1c MH |
886 | /* Try to release refcount of module, 0 means success. */ |
887 | static int try_release_module_ref(struct module *mod) | |
1da177e4 | 888 | { |
e513cc1c | 889 | int ret; |
1da177e4 | 890 | |
e513cc1c MH |
891 | /* Try to decrement refcnt which we set at loading */ |
892 | ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt); | |
893 | BUG_ON(ret < 0); | |
894 | if (ret) | |
895 | /* Someone can put this right now, recover with checking */ | |
896 | ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0); | |
1da177e4 | 897 | |
e513cc1c MH |
898 | return ret; |
899 | } | |
1da177e4 | 900 | |
e513cc1c MH |
901 | static int try_stop_module(struct module *mod, int flags, int *forced) |
902 | { | |
da39ba5e | 903 | /* If it's not unused, quit unless we're forcing. */ |
e513cc1c MH |
904 | if (try_release_module_ref(mod) != 0) { |
905 | *forced = try_force_unload(flags); | |
906 | if (!(*forced)) | |
1da177e4 LT |
907 | return -EWOULDBLOCK; |
908 | } | |
909 | ||
910 | /* Mark it as dying. */ | |
e513cc1c | 911 | mod->state = MODULE_STATE_GOING; |
1da177e4 | 912 | |
e513cc1c | 913 | return 0; |
1da177e4 LT |
914 | } |
915 | ||
d5db139a RR |
916 | /** |
917 | * module_refcount - return the refcount or -1 if unloading | |
918 | * | |
919 | * @mod: the module we're checking | |
920 | * | |
921 | * Returns: | |
922 | * -1 if the module is in the process of unloading | |
923 | * otherwise the number of references in the kernel to the module | |
924 | */ | |
925 | int module_refcount(struct module *mod) | |
1da177e4 | 926 | { |
d5db139a | 927 | return atomic_read(&mod->refcnt) - MODULE_REF_BASE; |
1da177e4 LT |
928 | } |
929 | EXPORT_SYMBOL(module_refcount); | |
930 | ||
931 | /* This exists whether we can unload or not */ | |
932 | static void free_module(struct module *mod); | |
933 | ||
17da2bd9 HC |
934 | SYSCALL_DEFINE2(delete_module, const char __user *, name_user, |
935 | unsigned int, flags) | |
1da177e4 LT |
936 | { |
937 | struct module *mod; | |
dfff0a06 | 938 | char name[MODULE_NAME_LEN]; |
1da177e4 LT |
939 | int ret, forced = 0; |
940 | ||
3d43321b | 941 | if (!capable(CAP_SYS_MODULE) || modules_disabled) |
dfff0a06 GKH |
942 | return -EPERM; |
943 | ||
944 | if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) | |
945 | return -EFAULT; | |
946 | name[MODULE_NAME_LEN-1] = '\0'; | |
947 | ||
3fc1f1e2 TH |
948 | if (mutex_lock_interruptible(&module_mutex) != 0) |
949 | return -EINTR; | |
1da177e4 LT |
950 | |
951 | mod = find_module(name); | |
952 | if (!mod) { | |
953 | ret = -ENOENT; | |
954 | goto out; | |
955 | } | |
956 | ||
2c02dfe7 | 957 | if (!list_empty(&mod->source_list)) { |
1da177e4 LT |
958 | /* Other modules depend on us: get rid of them first. */ |
959 | ret = -EWOULDBLOCK; | |
960 | goto out; | |
961 | } | |
962 | ||
963 | /* Doing init or already dying? */ | |
964 | if (mod->state != MODULE_STATE_LIVE) { | |
3f2b9c9c | 965 | /* FIXME: if (force), slam module count damn the torpedoes */ |
5e124169 | 966 | pr_debug("%s already dying\n", mod->name); |
1da177e4 LT |
967 | ret = -EBUSY; |
968 | goto out; | |
969 | } | |
970 | ||
971 | /* If it has an init func, it must have an exit func to unload */ | |
af49d924 | 972 | if (mod->init && !mod->exit) { |
fb169793 | 973 | forced = try_force_unload(flags); |
1da177e4 LT |
974 | if (!forced) { |
975 | /* This module can't be removed */ | |
976 | ret = -EBUSY; | |
977 | goto out; | |
978 | } | |
979 | } | |
980 | ||
1da177e4 LT |
981 | /* Stop the machine so refcounts can't move and disable module. */ |
982 | ret = try_stop_module(mod, flags, &forced); | |
983 | if (ret != 0) | |
984 | goto out; | |
985 | ||
df4b565e | 986 | mutex_unlock(&module_mutex); |
25985edc | 987 | /* Final destruction now no one is using it. */ |
df4b565e | 988 | if (mod->exit != NULL) |
1da177e4 | 989 | mod->exit(); |
df4b565e PO |
990 | blocking_notifier_call_chain(&module_notify_list, |
991 | MODULE_STATE_GOING, mod); | |
7e545d6e | 992 | klp_module_going(mod); |
7dcd182b JY |
993 | ftrace_release_mod(mod); |
994 | ||
22a9d645 | 995 | async_synchronize_full(); |
75676500 | 996 | |
e14af7ee | 997 | /* Store the name of the last unloaded module for diagnostic purposes */ |
efa5345e | 998 | strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); |
1da177e4 | 999 | |
75676500 RR |
1000 | free_module(mod); |
1001 | return 0; | |
1002 | out: | |
6389a385 | 1003 | mutex_unlock(&module_mutex); |
1da177e4 LT |
1004 | return ret; |
1005 | } | |
1006 | ||
d1e99d7a | 1007 | static inline void print_unload_info(struct seq_file *m, struct module *mod) |
1da177e4 LT |
1008 | { |
1009 | struct module_use *use; | |
1010 | int printed_something = 0; | |
1011 | ||
d5db139a | 1012 | seq_printf(m, " %i ", module_refcount(mod)); |
1da177e4 | 1013 | |
6da0b565 IA |
1014 | /* |
1015 | * Always include a trailing , so userspace can differentiate | |
1016 | * between this and the old multi-field proc format. | |
1017 | */ | |
2c02dfe7 | 1018 | list_for_each_entry(use, &mod->source_list, source_list) { |
1da177e4 | 1019 | printed_something = 1; |
2c02dfe7 | 1020 | seq_printf(m, "%s,", use->source->name); |
1da177e4 LT |
1021 | } |
1022 | ||
1da177e4 LT |
1023 | if (mod->init != NULL && mod->exit == NULL) { |
1024 | printed_something = 1; | |
6da0b565 | 1025 | seq_puts(m, "[permanent],"); |
1da177e4 LT |
1026 | } |
1027 | ||
1028 | if (!printed_something) | |
6da0b565 | 1029 | seq_puts(m, "-"); |
1da177e4 LT |
1030 | } |
1031 | ||
1032 | void __symbol_put(const char *symbol) | |
1033 | { | |
1034 | struct module *owner; | |
1da177e4 | 1035 | |
24da1cbf | 1036 | preempt_disable(); |
414fd31b | 1037 | if (!find_symbol(symbol, &owner, NULL, true, false)) |
1da177e4 LT |
1038 | BUG(); |
1039 | module_put(owner); | |
24da1cbf | 1040 | preempt_enable(); |
1da177e4 LT |
1041 | } |
1042 | EXPORT_SYMBOL(__symbol_put); | |
1043 | ||
7d1d16e4 | 1044 | /* Note this assumes addr is a function, which it currently always is. */ |
1da177e4 LT |
1045 | void symbol_put_addr(void *addr) |
1046 | { | |
5e376613 | 1047 | struct module *modaddr; |
7d1d16e4 | 1048 | unsigned long a = (unsigned long)dereference_function_descriptor(addr); |
1da177e4 | 1049 | |
7d1d16e4 | 1050 | if (core_kernel_text(a)) |
5e376613 | 1051 | return; |
1da177e4 | 1052 | |
275d7d44 PZ |
1053 | /* |
1054 | * Even though we hold a reference on the module; we still need to | |
1055 | * disable preemption in order to safely traverse the data structure. | |
1056 | */ | |
1057 | preempt_disable(); | |
7d1d16e4 | 1058 | modaddr = __module_text_address(a); |
a6e6abd5 | 1059 | BUG_ON(!modaddr); |
5e376613 | 1060 | module_put(modaddr); |
275d7d44 | 1061 | preempt_enable(); |
1da177e4 LT |
1062 | } |
1063 | EXPORT_SYMBOL_GPL(symbol_put_addr); | |
1064 | ||
1065 | static ssize_t show_refcnt(struct module_attribute *mattr, | |
4befb026 | 1066 | struct module_kobject *mk, char *buffer) |
1da177e4 | 1067 | { |
d5db139a | 1068 | return sprintf(buffer, "%i\n", module_refcount(mk->mod)); |
1da177e4 LT |
1069 | } |
1070 | ||
cca3e707 KS |
1071 | static struct module_attribute modinfo_refcnt = |
1072 | __ATTR(refcnt, 0444, show_refcnt, NULL); | |
1da177e4 | 1073 | |
d53799be SR |
1074 | void __module_get(struct module *module) |
1075 | { | |
1076 | if (module) { | |
1077 | preempt_disable(); | |
2f35c41f | 1078 | atomic_inc(&module->refcnt); |
d53799be SR |
1079 | trace_module_get(module, _RET_IP_); |
1080 | preempt_enable(); | |
1081 | } | |
1082 | } | |
1083 | EXPORT_SYMBOL(__module_get); | |
1084 | ||
1085 | bool try_module_get(struct module *module) | |
1086 | { | |
1087 | bool ret = true; | |
1088 | ||
1089 | if (module) { | |
1090 | preempt_disable(); | |
e513cc1c MH |
1091 | /* Note: here, we can fail to get a reference */ |
1092 | if (likely(module_is_live(module) && | |
1093 | atomic_inc_not_zero(&module->refcnt) != 0)) | |
d53799be | 1094 | trace_module_get(module, _RET_IP_); |
e513cc1c | 1095 | else |
d53799be SR |
1096 | ret = false; |
1097 | ||
1098 | preempt_enable(); | |
1099 | } | |
1100 | return ret; | |
1101 | } | |
1102 | EXPORT_SYMBOL(try_module_get); | |
1103 | ||
f6a57033 AV |
1104 | void module_put(struct module *module) |
1105 | { | |
e513cc1c MH |
1106 | int ret; |
1107 | ||
f6a57033 | 1108 | if (module) { |
e1783a24 | 1109 | preempt_disable(); |
e513cc1c MH |
1110 | ret = atomic_dec_if_positive(&module->refcnt); |
1111 | WARN_ON(ret < 0); /* Failed to put refcount */ | |
ae832d1e | 1112 | trace_module_put(module, _RET_IP_); |
e1783a24 | 1113 | preempt_enable(); |
f6a57033 AV |
1114 | } |
1115 | } | |
1116 | EXPORT_SYMBOL(module_put); | |
1117 | ||
1da177e4 | 1118 | #else /* !CONFIG_MODULE_UNLOAD */ |
d1e99d7a | 1119 | static inline void print_unload_info(struct seq_file *m, struct module *mod) |
1da177e4 LT |
1120 | { |
1121 | /* We don't know the usage count, or what modules are using. */ | |
6da0b565 | 1122 | seq_puts(m, " - -"); |
1da177e4 LT |
1123 | } |
1124 | ||
1125 | static inline void module_unload_free(struct module *mod) | |
1126 | { | |
1127 | } | |
1128 | ||
9bea7f23 | 1129 | int ref_module(struct module *a, struct module *b) |
1da177e4 | 1130 | { |
9bea7f23 | 1131 | return strong_try_module_get(b); |
1da177e4 | 1132 | } |
9bea7f23 | 1133 | EXPORT_SYMBOL_GPL(ref_module); |
1da177e4 | 1134 | |
9f85a4bb | 1135 | static inline int module_unload_init(struct module *mod) |
1da177e4 | 1136 | { |
9f85a4bb | 1137 | return 0; |
1da177e4 LT |
1138 | } |
1139 | #endif /* CONFIG_MODULE_UNLOAD */ | |
1140 | ||
53999bf3 KW |
1141 | static size_t module_flags_taint(struct module *mod, char *buf) |
1142 | { | |
1143 | size_t l = 0; | |
7fd8329b PM |
1144 | int i; |
1145 | ||
1146 | for (i = 0; i < TAINT_FLAGS_COUNT; i++) { | |
1147 | if (taint_flags[i].module && test_bit(i, &mod->taints)) | |
1148 | buf[l++] = taint_flags[i].true; | |
1149 | } | |
53999bf3 | 1150 | |
53999bf3 KW |
1151 | return l; |
1152 | } | |
1153 | ||
1f71740a | 1154 | static ssize_t show_initstate(struct module_attribute *mattr, |
4befb026 | 1155 | struct module_kobject *mk, char *buffer) |
1f71740a KS |
1156 | { |
1157 | const char *state = "unknown"; | |
1158 | ||
4befb026 | 1159 | switch (mk->mod->state) { |
1f71740a KS |
1160 | case MODULE_STATE_LIVE: |
1161 | state = "live"; | |
1162 | break; | |
1163 | case MODULE_STATE_COMING: | |
1164 | state = "coming"; | |
1165 | break; | |
1166 | case MODULE_STATE_GOING: | |
1167 | state = "going"; | |
1168 | break; | |
0d21b0e3 RR |
1169 | default: |
1170 | BUG(); | |
1f71740a KS |
1171 | } |
1172 | return sprintf(buffer, "%s\n", state); | |
1173 | } | |
1174 | ||
cca3e707 KS |
1175 | static struct module_attribute modinfo_initstate = |
1176 | __ATTR(initstate, 0444, show_initstate, NULL); | |
1f71740a | 1177 | |
88bfa324 KS |
1178 | static ssize_t store_uevent(struct module_attribute *mattr, |
1179 | struct module_kobject *mk, | |
1180 | const char *buffer, size_t count) | |
1181 | { | |
1182 | enum kobject_action action; | |
1183 | ||
1184 | if (kobject_action_type(buffer, count, &action) == 0) | |
1185 | kobject_uevent(&mk->kobj, action); | |
1186 | return count; | |
1187 | } | |
1188 | ||
cca3e707 KS |
1189 | struct module_attribute module_uevent = |
1190 | __ATTR(uevent, 0200, NULL, store_uevent); | |
1191 | ||
1192 | static ssize_t show_coresize(struct module_attribute *mattr, | |
1193 | struct module_kobject *mk, char *buffer) | |
1194 | { | |
7523e4dc | 1195 | return sprintf(buffer, "%u\n", mk->mod->core_layout.size); |
cca3e707 KS |
1196 | } |
1197 | ||
1198 | static struct module_attribute modinfo_coresize = | |
1199 | __ATTR(coresize, 0444, show_coresize, NULL); | |
1200 | ||
1201 | static ssize_t show_initsize(struct module_attribute *mattr, | |
1202 | struct module_kobject *mk, char *buffer) | |
1203 | { | |
7523e4dc | 1204 | return sprintf(buffer, "%u\n", mk->mod->init_layout.size); |
cca3e707 KS |
1205 | } |
1206 | ||
1207 | static struct module_attribute modinfo_initsize = | |
1208 | __ATTR(initsize, 0444, show_initsize, NULL); | |
1209 | ||
1210 | static ssize_t show_taint(struct module_attribute *mattr, | |
1211 | struct module_kobject *mk, char *buffer) | |
1212 | { | |
1213 | size_t l; | |
1214 | ||
1215 | l = module_flags_taint(mk->mod, buffer); | |
1216 | buffer[l++] = '\n'; | |
1217 | return l; | |
1218 | } | |
1219 | ||
1220 | static struct module_attribute modinfo_taint = | |
1221 | __ATTR(taint, 0444, show_taint, NULL); | |
88bfa324 | 1222 | |
03e88ae1 | 1223 | static struct module_attribute *modinfo_attrs[] = { |
cca3e707 | 1224 | &module_uevent, |
03e88ae1 GKH |
1225 | &modinfo_version, |
1226 | &modinfo_srcversion, | |
cca3e707 KS |
1227 | &modinfo_initstate, |
1228 | &modinfo_coresize, | |
1229 | &modinfo_initsize, | |
1230 | &modinfo_taint, | |
03e88ae1 | 1231 | #ifdef CONFIG_MODULE_UNLOAD |
cca3e707 | 1232 | &modinfo_refcnt, |
03e88ae1 GKH |
1233 | #endif |
1234 | NULL, | |
1235 | }; | |
1236 | ||
1da177e4 LT |
1237 | static const char vermagic[] = VERMAGIC_STRING; |
1238 | ||
c6e665c8 | 1239 | static int try_to_force_load(struct module *mod, const char *reason) |
826e4506 LT |
1240 | { |
1241 | #ifdef CONFIG_MODULE_FORCE_LOAD | |
25ddbb18 | 1242 | if (!test_taint(TAINT_FORCED_MODULE)) |
bddb12b3 | 1243 | pr_warn("%s: %s: kernel tainted.\n", mod->name, reason); |
373d4d09 | 1244 | add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE); |
826e4506 LT |
1245 | return 0; |
1246 | #else | |
1247 | return -ENOEXEC; | |
1248 | #endif | |
1249 | } | |
1250 | ||
1da177e4 | 1251 | #ifdef CONFIG_MODVERSIONS |
d4703aef RR |
1252 | /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */ |
1253 | static unsigned long maybe_relocated(unsigned long crc, | |
1254 | const struct module *crc_owner) | |
1255 | { | |
1256 | #ifdef ARCH_RELOCATES_KCRCTAB | |
1257 | if (crc_owner == NULL) | |
1258 | return crc - (unsigned long)reloc_start; | |
1259 | #endif | |
1260 | return crc; | |
1261 | } | |
1262 | ||
1da177e4 LT |
1263 | static int check_version(Elf_Shdr *sechdrs, |
1264 | unsigned int versindex, | |
1265 | const char *symname, | |
6da0b565 | 1266 | struct module *mod, |
d4703aef RR |
1267 | const unsigned long *crc, |
1268 | const struct module *crc_owner) | |
1da177e4 LT |
1269 | { |
1270 | unsigned int i, num_versions; | |
1271 | struct modversion_info *versions; | |
1272 | ||
1273 | /* Exporting module didn't supply crcs? OK, we're already tainted. */ | |
1274 | if (!crc) | |
1275 | return 1; | |
1276 | ||
a5dd6970 RR |
1277 | /* No versions at all? modprobe --force does this. */ |
1278 | if (versindex == 0) | |
1279 | return try_to_force_load(mod, symname) == 0; | |
1280 | ||
1da177e4 LT |
1281 | versions = (void *) sechdrs[versindex].sh_addr; |
1282 | num_versions = sechdrs[versindex].sh_size | |
1283 | / sizeof(struct modversion_info); | |
1284 | ||
1285 | for (i = 0; i < num_versions; i++) { | |
1286 | if (strcmp(versions[i].name, symname) != 0) | |
1287 | continue; | |
1288 | ||
d4703aef | 1289 | if (versions[i].crc == maybe_relocated(*crc, crc_owner)) |
1da177e4 | 1290 | return 1; |
5e124169 | 1291 | pr_debug("Found checksum %lX vs module %lX\n", |
d4703aef | 1292 | maybe_relocated(*crc, crc_owner), versions[i].crc); |
826e4506 | 1293 | goto bad_version; |
1da177e4 | 1294 | } |
826e4506 | 1295 | |
faaae2a5 LT |
1296 | /* Broken toolchain. Warn once, then let it go.. */ |
1297 | pr_warn_once("%s: no symbol version for %s\n", mod->name, symname); | |
1298 | return 1; | |
826e4506 LT |
1299 | |
1300 | bad_version: | |
6da0b565 | 1301 | pr_warn("%s: disagrees about version of symbol %s\n", |
826e4506 LT |
1302 | mod->name, symname); |
1303 | return 0; | |
1da177e4 LT |
1304 | } |
1305 | ||
1306 | static inline int check_modstruct_version(Elf_Shdr *sechdrs, | |
1307 | unsigned int versindex, | |
1308 | struct module *mod) | |
1309 | { | |
1310 | const unsigned long *crc; | |
1da177e4 | 1311 | |
926a59b1 PZ |
1312 | /* |
1313 | * Since this should be found in kernel (which can't be removed), no | |
1314 | * locking is necessary -- use preempt_disable() to placate lockdep. | |
1315 | */ | |
1316 | preempt_disable(); | |
b92021b0 | 1317 | if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL, |
926a59b1 PZ |
1318 | &crc, true, false)) { |
1319 | preempt_enable(); | |
1da177e4 | 1320 | BUG(); |
926a59b1 PZ |
1321 | } |
1322 | preempt_enable(); | |
a4b6a77b JH |
1323 | return check_version(sechdrs, versindex, |
1324 | VMLINUX_SYMBOL_STR(module_layout), mod, crc, | |
d4703aef | 1325 | NULL); |
1da177e4 LT |
1326 | } |
1327 | ||
91e37a79 RR |
1328 | /* First part is kernel version, which we ignore if module has crcs. */ |
1329 | static inline int same_magic(const char *amagic, const char *bmagic, | |
1330 | bool has_crcs) | |
1da177e4 | 1331 | { |
91e37a79 RR |
1332 | if (has_crcs) { |
1333 | amagic += strcspn(amagic, " "); | |
1334 | bmagic += strcspn(bmagic, " "); | |
1335 | } | |
1da177e4 LT |
1336 | return strcmp(amagic, bmagic) == 0; |
1337 | } | |
1338 | #else | |
1339 | static inline int check_version(Elf_Shdr *sechdrs, | |
1340 | unsigned int versindex, | |
1341 | const char *symname, | |
6da0b565 | 1342 | struct module *mod, |
d4703aef RR |
1343 | const unsigned long *crc, |
1344 | const struct module *crc_owner) | |
1da177e4 LT |
1345 | { |
1346 | return 1; | |
1347 | } | |
1348 | ||
1349 | static inline int check_modstruct_version(Elf_Shdr *sechdrs, | |
1350 | unsigned int versindex, | |
1351 | struct module *mod) | |
1352 | { | |
1353 | return 1; | |
1354 | } | |
1355 | ||
91e37a79 RR |
1356 | static inline int same_magic(const char *amagic, const char *bmagic, |
1357 | bool has_crcs) | |
1da177e4 LT |
1358 | { |
1359 | return strcmp(amagic, bmagic) == 0; | |
1360 | } | |
1361 | #endif /* CONFIG_MODVERSIONS */ | |
1362 | ||
75676500 | 1363 | /* Resolve a symbol for this module. I.e. if we find one, record usage. */ |
49668688 RR |
1364 | static const struct kernel_symbol *resolve_symbol(struct module *mod, |
1365 | const struct load_info *info, | |
414fd31b | 1366 | const char *name, |
9bea7f23 | 1367 | char ownername[]) |
1da177e4 LT |
1368 | { |
1369 | struct module *owner; | |
414fd31b | 1370 | const struct kernel_symbol *sym; |
1da177e4 | 1371 | const unsigned long *crc; |
9bea7f23 | 1372 | int err; |
1da177e4 | 1373 | |
d64810f5 PZ |
1374 | /* |
1375 | * The module_mutex should not be a heavily contended lock; | |
1376 | * if we get the occasional sleep here, we'll go an extra iteration | |
1377 | * in the wait_event_interruptible(), which is harmless. | |
1378 | */ | |
1379 | sched_annotate_sleep(); | |
75676500 | 1380 | mutex_lock(&module_mutex); |
414fd31b | 1381 | sym = find_symbol(name, &owner, &crc, |
25ddbb18 | 1382 | !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true); |
9bea7f23 RR |
1383 | if (!sym) |
1384 | goto unlock; | |
1385 | ||
49668688 RR |
1386 | if (!check_version(info->sechdrs, info->index.vers, name, mod, crc, |
1387 | owner)) { | |
9bea7f23 RR |
1388 | sym = ERR_PTR(-EINVAL); |
1389 | goto getname; | |
1da177e4 | 1390 | } |
9bea7f23 RR |
1391 | |
1392 | err = ref_module(mod, owner); | |
1393 | if (err) { | |
1394 | sym = ERR_PTR(err); | |
1395 | goto getname; | |
1396 | } | |
1397 | ||
1398 | getname: | |
1399 | /* We must make copy under the lock if we failed to get ref. */ | |
1400 | strncpy(ownername, module_name(owner), MODULE_NAME_LEN); | |
1401 | unlock: | |
75676500 | 1402 | mutex_unlock(&module_mutex); |
218ce735 | 1403 | return sym; |
1da177e4 LT |
1404 | } |
1405 | ||
49668688 RR |
1406 | static const struct kernel_symbol * |
1407 | resolve_symbol_wait(struct module *mod, | |
1408 | const struct load_info *info, | |
1409 | const char *name) | |
9bea7f23 RR |
1410 | { |
1411 | const struct kernel_symbol *ksym; | |
49668688 | 1412 | char owner[MODULE_NAME_LEN]; |
9bea7f23 RR |
1413 | |
1414 | if (wait_event_interruptible_timeout(module_wq, | |
49668688 RR |
1415 | !IS_ERR(ksym = resolve_symbol(mod, info, name, owner)) |
1416 | || PTR_ERR(ksym) != -EBUSY, | |
9bea7f23 | 1417 | 30 * HZ) <= 0) { |
bddb12b3 AM |
1418 | pr_warn("%s: gave up waiting for init of module %s.\n", |
1419 | mod->name, owner); | |
9bea7f23 RR |
1420 | } |
1421 | return ksym; | |
1422 | } | |
1423 | ||
1da177e4 LT |
1424 | /* |
1425 | * /sys/module/foo/sections stuff | |
1426 | * J. Corbet <corbet@lwn.net> | |
1427 | */ | |
8f6d0378 | 1428 | #ifdef CONFIG_SYSFS |
10b465aa | 1429 | |
8f6d0378 | 1430 | #ifdef CONFIG_KALLSYMS |
10b465aa BH |
1431 | static inline bool sect_empty(const Elf_Shdr *sect) |
1432 | { | |
1433 | return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0; | |
1434 | } | |
1435 | ||
6da0b565 | 1436 | struct module_sect_attr { |
a58730c4 RR |
1437 | struct module_attribute mattr; |
1438 | char *name; | |
1439 | unsigned long address; | |
1440 | }; | |
1441 | ||
6da0b565 | 1442 | struct module_sect_attrs { |
a58730c4 RR |
1443 | struct attribute_group grp; |
1444 | unsigned int nsections; | |
1445 | struct module_sect_attr attrs[0]; | |
1446 | }; | |
1447 | ||
1da177e4 | 1448 | static ssize_t module_sect_show(struct module_attribute *mattr, |
4befb026 | 1449 | struct module_kobject *mk, char *buf) |
1da177e4 LT |
1450 | { |
1451 | struct module_sect_attr *sattr = | |
1452 | container_of(mattr, struct module_sect_attr, mattr); | |
9f36e2c4 | 1453 | return sprintf(buf, "0x%pK\n", (void *)sattr->address); |
1da177e4 LT |
1454 | } |
1455 | ||
04b1db9f IN |
1456 | static void free_sect_attrs(struct module_sect_attrs *sect_attrs) |
1457 | { | |
a58730c4 | 1458 | unsigned int section; |
04b1db9f IN |
1459 | |
1460 | for (section = 0; section < sect_attrs->nsections; section++) | |
1461 | kfree(sect_attrs->attrs[section].name); | |
1462 | kfree(sect_attrs); | |
1463 | } | |
1464 | ||
8f6d0378 | 1465 | static void add_sect_attrs(struct module *mod, const struct load_info *info) |
1da177e4 LT |
1466 | { |
1467 | unsigned int nloaded = 0, i, size[2]; | |
1468 | struct module_sect_attrs *sect_attrs; | |
1469 | struct module_sect_attr *sattr; | |
1470 | struct attribute **gattr; | |
22a8bdeb | 1471 | |
1da177e4 | 1472 | /* Count loaded sections and allocate structures */ |
8f6d0378 RR |
1473 | for (i = 0; i < info->hdr->e_shnum; i++) |
1474 | if (!sect_empty(&info->sechdrs[i])) | |
1da177e4 LT |
1475 | nloaded++; |
1476 | size[0] = ALIGN(sizeof(*sect_attrs) | |
1477 | + nloaded * sizeof(sect_attrs->attrs[0]), | |
1478 | sizeof(sect_attrs->grp.attrs[0])); | |
1479 | size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]); | |
04b1db9f IN |
1480 | sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); |
1481 | if (sect_attrs == NULL) | |
1da177e4 LT |
1482 | return; |
1483 | ||
1484 | /* Setup section attributes. */ | |
1485 | sect_attrs->grp.name = "sections"; | |
1486 | sect_attrs->grp.attrs = (void *)sect_attrs + size[0]; | |
1487 | ||
04b1db9f | 1488 | sect_attrs->nsections = 0; |
1da177e4 LT |
1489 | sattr = §_attrs->attrs[0]; |
1490 | gattr = §_attrs->grp.attrs[0]; | |
8f6d0378 RR |
1491 | for (i = 0; i < info->hdr->e_shnum; i++) { |
1492 | Elf_Shdr *sec = &info->sechdrs[i]; | |
1493 | if (sect_empty(sec)) | |
35dead42 | 1494 | continue; |
8f6d0378 RR |
1495 | sattr->address = sec->sh_addr; |
1496 | sattr->name = kstrdup(info->secstrings + sec->sh_name, | |
04b1db9f IN |
1497 | GFP_KERNEL); |
1498 | if (sattr->name == NULL) | |
1499 | goto out; | |
1500 | sect_attrs->nsections++; | |
361795b1 | 1501 | sysfs_attr_init(&sattr->mattr.attr); |
1da177e4 LT |
1502 | sattr->mattr.show = module_sect_show; |
1503 | sattr->mattr.store = NULL; | |
1504 | sattr->mattr.attr.name = sattr->name; | |
1da177e4 LT |
1505 | sattr->mattr.attr.mode = S_IRUGO; |
1506 | *(gattr++) = &(sattr++)->mattr.attr; | |
1507 | } | |
1508 | *gattr = NULL; | |
1509 | ||
1510 | if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) | |
1511 | goto out; | |
1512 | ||
1513 | mod->sect_attrs = sect_attrs; | |
1514 | return; | |
1515 | out: | |
04b1db9f | 1516 | free_sect_attrs(sect_attrs); |
1da177e4 LT |
1517 | } |
1518 | ||
1519 | static void remove_sect_attrs(struct module *mod) | |
1520 | { | |
1521 | if (mod->sect_attrs) { | |
1522 | sysfs_remove_group(&mod->mkobj.kobj, | |
1523 | &mod->sect_attrs->grp); | |
1524 | /* We are positive that no one is using any sect attrs | |
1525 | * at this point. Deallocate immediately. */ | |
04b1db9f | 1526 | free_sect_attrs(mod->sect_attrs); |
1da177e4 LT |
1527 | mod->sect_attrs = NULL; |
1528 | } | |
1529 | } | |
1530 | ||
6d760133 RM |
1531 | /* |
1532 | * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. | |
1533 | */ | |
1534 | ||
1535 | struct module_notes_attrs { | |
1536 | struct kobject *dir; | |
1537 | unsigned int notes; | |
1538 | struct bin_attribute attrs[0]; | |
1539 | }; | |
1540 | ||
2c3c8bea | 1541 | static ssize_t module_notes_read(struct file *filp, struct kobject *kobj, |
6d760133 RM |
1542 | struct bin_attribute *bin_attr, |
1543 | char *buf, loff_t pos, size_t count) | |
1544 | { | |
1545 | /* | |
1546 | * The caller checked the pos and count against our size. | |
1547 | */ | |
1548 | memcpy(buf, bin_attr->private + pos, count); | |
1549 | return count; | |
1550 | } | |
1551 | ||
1552 | static void free_notes_attrs(struct module_notes_attrs *notes_attrs, | |
1553 | unsigned int i) | |
1554 | { | |
1555 | if (notes_attrs->dir) { | |
1556 | while (i-- > 0) | |
1557 | sysfs_remove_bin_file(notes_attrs->dir, | |
1558 | ¬es_attrs->attrs[i]); | |
e9432093 | 1559 | kobject_put(notes_attrs->dir); |
6d760133 RM |
1560 | } |
1561 | kfree(notes_attrs); | |
1562 | } | |
1563 | ||
8f6d0378 | 1564 | static void add_notes_attrs(struct module *mod, const struct load_info *info) |
6d760133 RM |
1565 | { |
1566 | unsigned int notes, loaded, i; | |
1567 | struct module_notes_attrs *notes_attrs; | |
1568 | struct bin_attribute *nattr; | |
1569 | ||
ea6bff36 IM |
1570 | /* failed to create section attributes, so can't create notes */ |
1571 | if (!mod->sect_attrs) | |
1572 | return; | |
1573 | ||
6d760133 RM |
1574 | /* Count notes sections and allocate structures. */ |
1575 | notes = 0; | |
8f6d0378 RR |
1576 | for (i = 0; i < info->hdr->e_shnum; i++) |
1577 | if (!sect_empty(&info->sechdrs[i]) && | |
1578 | (info->sechdrs[i].sh_type == SHT_NOTE)) | |
6d760133 RM |
1579 | ++notes; |
1580 | ||
1581 | if (notes == 0) | |
1582 | return; | |
1583 | ||
1584 | notes_attrs = kzalloc(sizeof(*notes_attrs) | |
1585 | + notes * sizeof(notes_attrs->attrs[0]), | |
1586 | GFP_KERNEL); | |
1587 | if (notes_attrs == NULL) | |
1588 | return; | |
1589 | ||
1590 | notes_attrs->notes = notes; | |
1591 | nattr = ¬es_attrs->attrs[0]; | |
8f6d0378 RR |
1592 | for (loaded = i = 0; i < info->hdr->e_shnum; ++i) { |
1593 | if (sect_empty(&info->sechdrs[i])) | |
6d760133 | 1594 | continue; |
8f6d0378 | 1595 | if (info->sechdrs[i].sh_type == SHT_NOTE) { |
361795b1 | 1596 | sysfs_bin_attr_init(nattr); |
6d760133 RM |
1597 | nattr->attr.name = mod->sect_attrs->attrs[loaded].name; |
1598 | nattr->attr.mode = S_IRUGO; | |
8f6d0378 RR |
1599 | nattr->size = info->sechdrs[i].sh_size; |
1600 | nattr->private = (void *) info->sechdrs[i].sh_addr; | |
6d760133 RM |
1601 | nattr->read = module_notes_read; |
1602 | ++nattr; | |
1603 | } | |
1604 | ++loaded; | |
1605 | } | |
1606 | ||
4ff6abff | 1607 | notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); |
6d760133 RM |
1608 | if (!notes_attrs->dir) |
1609 | goto out; | |
1610 | ||
1611 | for (i = 0; i < notes; ++i) | |
1612 | if (sysfs_create_bin_file(notes_attrs->dir, | |
1613 | ¬es_attrs->attrs[i])) | |
1614 | goto out; | |
1615 | ||
1616 | mod->notes_attrs = notes_attrs; | |
1617 | return; | |
1618 | ||
1619 | out: | |
1620 | free_notes_attrs(notes_attrs, i); | |
1621 | } | |
1622 | ||
1623 | static void remove_notes_attrs(struct module *mod) | |
1624 | { | |
1625 | if (mod->notes_attrs) | |
1626 | free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); | |
1627 | } | |
1628 | ||
1da177e4 | 1629 | #else |
04b1db9f | 1630 | |
8f6d0378 RR |
1631 | static inline void add_sect_attrs(struct module *mod, |
1632 | const struct load_info *info) | |
1da177e4 LT |
1633 | { |
1634 | } | |
1635 | ||
1636 | static inline void remove_sect_attrs(struct module *mod) | |
1637 | { | |
1638 | } | |
6d760133 | 1639 | |
8f6d0378 RR |
1640 | static inline void add_notes_attrs(struct module *mod, |
1641 | const struct load_info *info) | |
6d760133 RM |
1642 | { |
1643 | } | |
1644 | ||
1645 | static inline void remove_notes_attrs(struct module *mod) | |
1646 | { | |
1647 | } | |
8f6d0378 | 1648 | #endif /* CONFIG_KALLSYMS */ |
1da177e4 | 1649 | |
80a3d1bb RR |
1650 | static void add_usage_links(struct module *mod) |
1651 | { | |
1652 | #ifdef CONFIG_MODULE_UNLOAD | |
1653 | struct module_use *use; | |
1654 | int nowarn; | |
1655 | ||
75676500 | 1656 | mutex_lock(&module_mutex); |
80a3d1bb RR |
1657 | list_for_each_entry(use, &mod->target_list, target_list) { |
1658 | nowarn = sysfs_create_link(use->target->holders_dir, | |
1659 | &mod->mkobj.kobj, mod->name); | |
1660 | } | |
75676500 | 1661 | mutex_unlock(&module_mutex); |
80a3d1bb RR |
1662 | #endif |
1663 | } | |
1664 | ||
1665 | static void del_usage_links(struct module *mod) | |
1666 | { | |
1667 | #ifdef CONFIG_MODULE_UNLOAD | |
1668 | struct module_use *use; | |
1669 | ||
75676500 | 1670 | mutex_lock(&module_mutex); |
80a3d1bb RR |
1671 | list_for_each_entry(use, &mod->target_list, target_list) |
1672 | sysfs_remove_link(use->target->holders_dir, mod->name); | |
75676500 | 1673 | mutex_unlock(&module_mutex); |
80a3d1bb RR |
1674 | #endif |
1675 | } | |
1676 | ||
6407ebb2 | 1677 | static int module_add_modinfo_attrs(struct module *mod) |
c988d2b2 MD |
1678 | { |
1679 | struct module_attribute *attr; | |
03e88ae1 | 1680 | struct module_attribute *temp_attr; |
c988d2b2 MD |
1681 | int error = 0; |
1682 | int i; | |
1683 | ||
03e88ae1 GKH |
1684 | mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * |
1685 | (ARRAY_SIZE(modinfo_attrs) + 1)), | |
1686 | GFP_KERNEL); | |
1687 | if (!mod->modinfo_attrs) | |
1688 | return -ENOMEM; | |
1689 | ||
1690 | temp_attr = mod->modinfo_attrs; | |
c988d2b2 | 1691 | for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) { |
c75b590d | 1692 | if (!attr->test || attr->test(mod)) { |
03e88ae1 | 1693 | memcpy(temp_attr, attr, sizeof(*temp_attr)); |
361795b1 | 1694 | sysfs_attr_init(&temp_attr->attr); |
6da0b565 IA |
1695 | error = sysfs_create_file(&mod->mkobj.kobj, |
1696 | &temp_attr->attr); | |
03e88ae1 GKH |
1697 | ++temp_attr; |
1698 | } | |
c988d2b2 MD |
1699 | } |
1700 | return error; | |
1701 | } | |
1702 | ||
6407ebb2 | 1703 | static void module_remove_modinfo_attrs(struct module *mod) |
c988d2b2 MD |
1704 | { |
1705 | struct module_attribute *attr; | |
1706 | int i; | |
1707 | ||
03e88ae1 GKH |
1708 | for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { |
1709 | /* pick a field to test for end of list */ | |
1710 | if (!attr->attr.name) | |
1711 | break; | |
6da0b565 | 1712 | sysfs_remove_file(&mod->mkobj.kobj, &attr->attr); |
03e88ae1 GKH |
1713 | if (attr->free) |
1714 | attr->free(mod); | |
c988d2b2 | 1715 | } |
03e88ae1 | 1716 | kfree(mod->modinfo_attrs); |
c988d2b2 | 1717 | } |
1da177e4 | 1718 | |
942e4431 LZ |
1719 | static void mod_kobject_put(struct module *mod) |
1720 | { | |
1721 | DECLARE_COMPLETION_ONSTACK(c); | |
1722 | mod->mkobj.kobj_completion = &c; | |
1723 | kobject_put(&mod->mkobj.kobj); | |
1724 | wait_for_completion(&c); | |
1725 | } | |
1726 | ||
6407ebb2 | 1727 | static int mod_sysfs_init(struct module *mod) |
1da177e4 LT |
1728 | { |
1729 | int err; | |
6494a93d | 1730 | struct kobject *kobj; |
1da177e4 | 1731 | |
823bccfc | 1732 | if (!module_sysfs_initialized) { |
bddb12b3 | 1733 | pr_err("%s: module sysfs not initialized\n", mod->name); |
1cc5f714 ES |
1734 | err = -EINVAL; |
1735 | goto out; | |
1736 | } | |
6494a93d GKH |
1737 | |
1738 | kobj = kset_find_obj(module_kset, mod->name); | |
1739 | if (kobj) { | |
bddb12b3 | 1740 | pr_err("%s: module is already loaded\n", mod->name); |
6494a93d GKH |
1741 | kobject_put(kobj); |
1742 | err = -EINVAL; | |
1743 | goto out; | |
1744 | } | |
1745 | ||
1da177e4 | 1746 | mod->mkobj.mod = mod; |
e17e0f51 | 1747 | |
ac3c8141 GKH |
1748 | memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); |
1749 | mod->mkobj.kobj.kset = module_kset; | |
1750 | err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, | |
1751 | "%s", mod->name); | |
1752 | if (err) | |
942e4431 | 1753 | mod_kobject_put(mod); |
270a6c4c | 1754 | |
97c146ef | 1755 | /* delay uevent until full sysfs population */ |
270a6c4c KS |
1756 | out: |
1757 | return err; | |
1758 | } | |
1759 | ||
6407ebb2 | 1760 | static int mod_sysfs_setup(struct module *mod, |
8f6d0378 | 1761 | const struct load_info *info, |
270a6c4c KS |
1762 | struct kernel_param *kparam, |
1763 | unsigned int num_params) | |
1764 | { | |
1765 | int err; | |
1766 | ||
80a3d1bb RR |
1767 | err = mod_sysfs_init(mod); |
1768 | if (err) | |
1769 | goto out; | |
1770 | ||
4ff6abff | 1771 | mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); |
240936e1 AM |
1772 | if (!mod->holders_dir) { |
1773 | err = -ENOMEM; | |
270a6c4c | 1774 | goto out_unreg; |
240936e1 | 1775 | } |
270a6c4c | 1776 | |
1da177e4 LT |
1777 | err = module_param_sysfs_setup(mod, kparam, num_params); |
1778 | if (err) | |
270a6c4c | 1779 | goto out_unreg_holders; |
1da177e4 | 1780 | |
c988d2b2 MD |
1781 | err = module_add_modinfo_attrs(mod); |
1782 | if (err) | |
e17e0f51 | 1783 | goto out_unreg_param; |
c988d2b2 | 1784 | |
80a3d1bb | 1785 | add_usage_links(mod); |
8f6d0378 RR |
1786 | add_sect_attrs(mod, info); |
1787 | add_notes_attrs(mod, info); | |
80a3d1bb | 1788 | |
e17e0f51 | 1789 | kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD); |
1da177e4 LT |
1790 | return 0; |
1791 | ||
e17e0f51 KS |
1792 | out_unreg_param: |
1793 | module_param_sysfs_remove(mod); | |
270a6c4c | 1794 | out_unreg_holders: |
78a2d906 | 1795 | kobject_put(mod->holders_dir); |
270a6c4c | 1796 | out_unreg: |
942e4431 | 1797 | mod_kobject_put(mod); |
80a3d1bb | 1798 | out: |
1da177e4 LT |
1799 | return err; |
1800 | } | |
34e4e2fe DL |
1801 | |
1802 | static void mod_sysfs_fini(struct module *mod) | |
1803 | { | |
8f6d0378 RR |
1804 | remove_notes_attrs(mod); |
1805 | remove_sect_attrs(mod); | |
942e4431 | 1806 | mod_kobject_put(mod); |
34e4e2fe DL |
1807 | } |
1808 | ||
cf2fde7b RR |
1809 | static void init_param_lock(struct module *mod) |
1810 | { | |
1811 | mutex_init(&mod->param_lock); | |
1812 | } | |
8f6d0378 | 1813 | #else /* !CONFIG_SYSFS */ |
34e4e2fe | 1814 | |
8f6d0378 RR |
1815 | static int mod_sysfs_setup(struct module *mod, |
1816 | const struct load_info *info, | |
6407ebb2 RR |
1817 | struct kernel_param *kparam, |
1818 | unsigned int num_params) | |
1819 | { | |
1820 | return 0; | |
1821 | } | |
1822 | ||
34e4e2fe DL |
1823 | static void mod_sysfs_fini(struct module *mod) |
1824 | { | |
1825 | } | |
1826 | ||
36b0360d RR |
1827 | static void module_remove_modinfo_attrs(struct module *mod) |
1828 | { | |
1829 | } | |
1830 | ||
80a3d1bb RR |
1831 | static void del_usage_links(struct module *mod) |
1832 | { | |
1833 | } | |
1834 | ||
cf2fde7b RR |
1835 | static void init_param_lock(struct module *mod) |
1836 | { | |
1837 | } | |
34e4e2fe | 1838 | #endif /* CONFIG_SYSFS */ |
1da177e4 | 1839 | |
36b0360d | 1840 | static void mod_sysfs_teardown(struct module *mod) |
1da177e4 | 1841 | { |
80a3d1bb | 1842 | del_usage_links(mod); |
c988d2b2 | 1843 | module_remove_modinfo_attrs(mod); |
1da177e4 | 1844 | module_param_sysfs_remove(mod); |
78a2d906 GKH |
1845 | kobject_put(mod->mkobj.drivers_dir); |
1846 | kobject_put(mod->holders_dir); | |
34e4e2fe | 1847 | mod_sysfs_fini(mod); |
1da177e4 LT |
1848 | } |
1849 | ||
84e1c6bb MC |
1850 | #ifdef CONFIG_DEBUG_SET_MODULE_RONX |
1851 | /* | |
1852 | * LKM RO/NX protection: protect module's text/ro-data | |
1853 | * from modification and any data from execution. | |
85c898db RR |
1854 | * |
1855 | * General layout of module is: | |
444d13ff JY |
1856 | * [text] [read-only-data] [ro-after-init] [writable data] |
1857 | * text_size -----^ ^ ^ ^ | |
1858 | * ro_size ------------------------| | | | |
1859 | * ro_after_init_size -----------------------------| | | |
1860 | * size -----------------------------------------------------------| | |
85c898db RR |
1861 | * |
1862 | * These values are always page-aligned (as is base) | |
84e1c6bb | 1863 | */ |
85c898db RR |
1864 | static void frob_text(const struct module_layout *layout, |
1865 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 1866 | { |
85c898db RR |
1867 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
1868 | BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1)); | |
1869 | set_memory((unsigned long)layout->base, | |
1870 | layout->text_size >> PAGE_SHIFT); | |
84e1c6bb | 1871 | } |
84e1c6bb | 1872 | |
85c898db RR |
1873 | static void frob_rodata(const struct module_layout *layout, |
1874 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 1875 | { |
85c898db RR |
1876 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
1877 | BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1)); | |
1878 | BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1)); | |
1879 | set_memory((unsigned long)layout->base + layout->text_size, | |
1880 | (layout->ro_size - layout->text_size) >> PAGE_SHIFT); | |
84e1c6bb MC |
1881 | } |
1882 | ||
444d13ff JY |
1883 | static void frob_ro_after_init(const struct module_layout *layout, |
1884 | int (*set_memory)(unsigned long start, int num_pages)) | |
1885 | { | |
1886 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); | |
1887 | BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1)); | |
1888 | BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1)); | |
1889 | set_memory((unsigned long)layout->base + layout->ro_size, | |
1890 | (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT); | |
1891 | } | |
1892 | ||
85c898db RR |
1893 | static void frob_writable_data(const struct module_layout *layout, |
1894 | int (*set_memory)(unsigned long start, int num_pages)) | |
84e1c6bb | 1895 | { |
85c898db | 1896 | BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1)); |
444d13ff | 1897 | BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1)); |
85c898db | 1898 | BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1)); |
444d13ff JY |
1899 | set_memory((unsigned long)layout->base + layout->ro_after_init_size, |
1900 | (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT); | |
84e1c6bb | 1901 | } |
84e1c6bb | 1902 | |
85c898db RR |
1903 | /* livepatching wants to disable read-only so it can frob module. */ |
1904 | void module_disable_ro(const struct module *mod) | |
20ef10c1 | 1905 | { |
39290b38 AT |
1906 | if (!rodata_enabled) |
1907 | return; | |
1908 | ||
85c898db RR |
1909 | frob_text(&mod->core_layout, set_memory_rw); |
1910 | frob_rodata(&mod->core_layout, set_memory_rw); | |
444d13ff | 1911 | frob_ro_after_init(&mod->core_layout, set_memory_rw); |
85c898db RR |
1912 | frob_text(&mod->init_layout, set_memory_rw); |
1913 | frob_rodata(&mod->init_layout, set_memory_rw); | |
20ef10c1 | 1914 | } |
84e1c6bb | 1915 | |
444d13ff | 1916 | void module_enable_ro(const struct module *mod, bool after_init) |
01526ed0 | 1917 | { |
39290b38 AT |
1918 | if (!rodata_enabled) |
1919 | return; | |
1920 | ||
85c898db RR |
1921 | frob_text(&mod->core_layout, set_memory_ro); |
1922 | frob_rodata(&mod->core_layout, set_memory_ro); | |
1923 | frob_text(&mod->init_layout, set_memory_ro); | |
1924 | frob_rodata(&mod->init_layout, set_memory_ro); | |
444d13ff JY |
1925 | |
1926 | if (after_init) | |
1927 | frob_ro_after_init(&mod->core_layout, set_memory_ro); | |
84e1c6bb MC |
1928 | } |
1929 | ||
85c898db | 1930 | static void module_enable_nx(const struct module *mod) |
01526ed0 | 1931 | { |
85c898db | 1932 | frob_rodata(&mod->core_layout, set_memory_nx); |
444d13ff | 1933 | frob_ro_after_init(&mod->core_layout, set_memory_nx); |
85c898db RR |
1934 | frob_writable_data(&mod->core_layout, set_memory_nx); |
1935 | frob_rodata(&mod->init_layout, set_memory_nx); | |
1936 | frob_writable_data(&mod->init_layout, set_memory_nx); | |
01526ed0 JG |
1937 | } |
1938 | ||
85c898db | 1939 | static void module_disable_nx(const struct module *mod) |
01526ed0 | 1940 | { |
85c898db | 1941 | frob_rodata(&mod->core_layout, set_memory_x); |
444d13ff | 1942 | frob_ro_after_init(&mod->core_layout, set_memory_x); |
85c898db RR |
1943 | frob_writable_data(&mod->core_layout, set_memory_x); |
1944 | frob_rodata(&mod->init_layout, set_memory_x); | |
1945 | frob_writable_data(&mod->init_layout, set_memory_x); | |
84e1c6bb MC |
1946 | } |
1947 | ||
1948 | /* Iterate through all modules and set each module's text as RW */ | |
5d05c708 | 1949 | void set_all_modules_text_rw(void) |
84e1c6bb MC |
1950 | { |
1951 | struct module *mod; | |
1952 | ||
39290b38 AT |
1953 | if (!rodata_enabled) |
1954 | return; | |
1955 | ||
84e1c6bb MC |
1956 | mutex_lock(&module_mutex); |
1957 | list_for_each_entry_rcu(mod, &modules, list) { | |
0d21b0e3 RR |
1958 | if (mod->state == MODULE_STATE_UNFORMED) |
1959 | continue; | |
85c898db RR |
1960 | |
1961 | frob_text(&mod->core_layout, set_memory_rw); | |
1962 | frob_text(&mod->init_layout, set_memory_rw); | |
84e1c6bb MC |
1963 | } |
1964 | mutex_unlock(&module_mutex); | |
1965 | } | |
1966 | ||
1967 | /* Iterate through all modules and set each module's text as RO */ | |
5d05c708 | 1968 | void set_all_modules_text_ro(void) |
84e1c6bb MC |
1969 | { |
1970 | struct module *mod; | |
1971 | ||
39290b38 AT |
1972 | if (!rodata_enabled) |
1973 | return; | |
1974 | ||
84e1c6bb MC |
1975 | mutex_lock(&module_mutex); |
1976 | list_for_each_entry_rcu(mod, &modules, list) { | |
905dd707 AT |
1977 | /* |
1978 | * Ignore going modules since it's possible that ro | |
1979 | * protection has already been disabled, otherwise we'll | |
1980 | * run into protection faults at module deallocation. | |
1981 | */ | |
1982 | if (mod->state == MODULE_STATE_UNFORMED || | |
1983 | mod->state == MODULE_STATE_GOING) | |
0d21b0e3 | 1984 | continue; |
85c898db RR |
1985 | |
1986 | frob_text(&mod->core_layout, set_memory_ro); | |
1987 | frob_text(&mod->init_layout, set_memory_ro); | |
84e1c6bb MC |
1988 | } |
1989 | mutex_unlock(&module_mutex); | |
1990 | } | |
85c898db RR |
1991 | |
1992 | static void disable_ro_nx(const struct module_layout *layout) | |
1993 | { | |
39290b38 AT |
1994 | if (rodata_enabled) { |
1995 | frob_text(layout, set_memory_rw); | |
1996 | frob_rodata(layout, set_memory_rw); | |
1997 | frob_ro_after_init(layout, set_memory_rw); | |
1998 | } | |
85c898db | 1999 | frob_rodata(layout, set_memory_x); |
444d13ff | 2000 | frob_ro_after_init(layout, set_memory_x); |
85c898db RR |
2001 | frob_writable_data(layout, set_memory_x); |
2002 | } | |
2003 | ||
84e1c6bb | 2004 | #else |
85c898db RR |
2005 | static void disable_ro_nx(const struct module_layout *layout) { } |
2006 | static void module_enable_nx(const struct module *mod) { } | |
2007 | static void module_disable_nx(const struct module *mod) { } | |
84e1c6bb MC |
2008 | #endif |
2009 | ||
1ce15ef4 JY |
2010 | #ifdef CONFIG_LIVEPATCH |
2011 | /* | |
2012 | * Persist Elf information about a module. Copy the Elf header, | |
2013 | * section header table, section string table, and symtab section | |
2014 | * index from info to mod->klp_info. | |
2015 | */ | |
2016 | static int copy_module_elf(struct module *mod, struct load_info *info) | |
2017 | { | |
2018 | unsigned int size, symndx; | |
2019 | int ret; | |
2020 | ||
2021 | size = sizeof(*mod->klp_info); | |
2022 | mod->klp_info = kmalloc(size, GFP_KERNEL); | |
2023 | if (mod->klp_info == NULL) | |
2024 | return -ENOMEM; | |
2025 | ||
2026 | /* Elf header */ | |
2027 | size = sizeof(mod->klp_info->hdr); | |
2028 | memcpy(&mod->klp_info->hdr, info->hdr, size); | |
2029 | ||
2030 | /* Elf section header table */ | |
2031 | size = sizeof(*info->sechdrs) * info->hdr->e_shnum; | |
2032 | mod->klp_info->sechdrs = kmalloc(size, GFP_KERNEL); | |
2033 | if (mod->klp_info->sechdrs == NULL) { | |
2034 | ret = -ENOMEM; | |
2035 | goto free_info; | |
2036 | } | |
2037 | memcpy(mod->klp_info->sechdrs, info->sechdrs, size); | |
2038 | ||
2039 | /* Elf section name string table */ | |
2040 | size = info->sechdrs[info->hdr->e_shstrndx].sh_size; | |
2041 | mod->klp_info->secstrings = kmalloc(size, GFP_KERNEL); | |
2042 | if (mod->klp_info->secstrings == NULL) { | |
2043 | ret = -ENOMEM; | |
2044 | goto free_sechdrs; | |
2045 | } | |
2046 | memcpy(mod->klp_info->secstrings, info->secstrings, size); | |
2047 | ||
2048 | /* Elf symbol section index */ | |
2049 | symndx = info->index.sym; | |
2050 | mod->klp_info->symndx = symndx; | |
2051 | ||
2052 | /* | |
2053 | * For livepatch modules, core_kallsyms.symtab is a complete | |
2054 | * copy of the original symbol table. Adjust sh_addr to point | |
2055 | * to core_kallsyms.symtab since the copy of the symtab in module | |
2056 | * init memory is freed at the end of do_init_module(). | |
2057 | */ | |
2058 | mod->klp_info->sechdrs[symndx].sh_addr = \ | |
2059 | (unsigned long) mod->core_kallsyms.symtab; | |
2060 | ||
2061 | return 0; | |
2062 | ||
2063 | free_sechdrs: | |
2064 | kfree(mod->klp_info->sechdrs); | |
2065 | free_info: | |
2066 | kfree(mod->klp_info); | |
2067 | return ret; | |
2068 | } | |
2069 | ||
2070 | static void free_module_elf(struct module *mod) | |
2071 | { | |
2072 | kfree(mod->klp_info->sechdrs); | |
2073 | kfree(mod->klp_info->secstrings); | |
2074 | kfree(mod->klp_info); | |
2075 | } | |
2076 | #else /* !CONFIG_LIVEPATCH */ | |
2077 | static int copy_module_elf(struct module *mod, struct load_info *info) | |
2078 | { | |
2079 | return 0; | |
2080 | } | |
2081 | ||
2082 | static void free_module_elf(struct module *mod) | |
2083 | { | |
2084 | } | |
2085 | #endif /* CONFIG_LIVEPATCH */ | |
2086 | ||
be1f221c | 2087 | void __weak module_memfree(void *module_region) |
74e08fcf JB |
2088 | { |
2089 | vfree(module_region); | |
2090 | } | |
2091 | ||
2092 | void __weak module_arch_cleanup(struct module *mod) | |
2093 | { | |
2094 | } | |
2095 | ||
d453cded RR |
2096 | void __weak module_arch_freeing_init(struct module *mod) |
2097 | { | |
2098 | } | |
2099 | ||
75676500 | 2100 | /* Free a module, remove from lists, etc. */ |
1da177e4 LT |
2101 | static void free_module(struct module *mod) |
2102 | { | |
7ead8b83 LZ |
2103 | trace_module_free(mod); |
2104 | ||
36b0360d | 2105 | mod_sysfs_teardown(mod); |
1da177e4 | 2106 | |
944a1fa0 RR |
2107 | /* We leave it in list to prevent duplicate loads, but make sure |
2108 | * that noone uses it while it's being deconstructed. */ | |
d3051b48 | 2109 | mutex_lock(&module_mutex); |
944a1fa0 | 2110 | mod->state = MODULE_STATE_UNFORMED; |
d3051b48 | 2111 | mutex_unlock(&module_mutex); |
944a1fa0 | 2112 | |
b82bab4b JB |
2113 | /* Remove dynamic debug info */ |
2114 | ddebug_remove_module(mod->name); | |
2115 | ||
1da177e4 LT |
2116 | /* Arch-specific cleanup. */ |
2117 | module_arch_cleanup(mod); | |
2118 | ||
2119 | /* Module unload stuff */ | |
2120 | module_unload_free(mod); | |
2121 | ||
e180a6b7 RR |
2122 | /* Free any allocated parameters. */ |
2123 | destroy_params(mod->kp, mod->num_kp); | |
2124 | ||
1ce15ef4 JY |
2125 | if (is_livepatch_module(mod)) |
2126 | free_module_elf(mod); | |
2127 | ||
944a1fa0 RR |
2128 | /* Now we can delete it from the lists */ |
2129 | mutex_lock(&module_mutex); | |
461e34ae MH |
2130 | /* Unlink carefully: kallsyms could be walking list. */ |
2131 | list_del_rcu(&mod->list); | |
93c2e105 | 2132 | mod_tree_remove(mod); |
0286b5ea | 2133 | /* Remove this module from bug list, this uses list_del_rcu */ |
461e34ae | 2134 | module_bug_cleanup(mod); |
0be964be PZ |
2135 | /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */ |
2136 | synchronize_sched(); | |
944a1fa0 RR |
2137 | mutex_unlock(&module_mutex); |
2138 | ||
85c898db RR |
2139 | /* This may be empty, but that's OK */ |
2140 | disable_ro_nx(&mod->init_layout); | |
d453cded | 2141 | module_arch_freeing_init(mod); |
7523e4dc | 2142 | module_memfree(mod->init_layout.base); |
1da177e4 | 2143 | kfree(mod->args); |
259354de | 2144 | percpu_modfree(mod); |
9f85a4bb | 2145 | |
35a9393c | 2146 | /* Free lock-classes; relies on the preceding sync_rcu(). */ |
7523e4dc | 2147 | lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size); |
fbb9ce95 | 2148 | |
1da177e4 | 2149 | /* Finally, free the core (containing the module structure) */ |
85c898db | 2150 | disable_ro_nx(&mod->core_layout); |
7523e4dc | 2151 | module_memfree(mod->core_layout.base); |
eb8cdec4 BS |
2152 | |
2153 | #ifdef CONFIG_MPU | |
2154 | update_protections(current->mm); | |
2155 | #endif | |
1da177e4 LT |
2156 | } |
2157 | ||
2158 | void *__symbol_get(const char *symbol) | |
2159 | { | |
2160 | struct module *owner; | |
414fd31b | 2161 | const struct kernel_symbol *sym; |
1da177e4 | 2162 | |
24da1cbf | 2163 | preempt_disable(); |
414fd31b TA |
2164 | sym = find_symbol(symbol, &owner, NULL, true, true); |
2165 | if (sym && strong_try_module_get(owner)) | |
2166 | sym = NULL; | |
24da1cbf | 2167 | preempt_enable(); |
1da177e4 | 2168 | |
414fd31b | 2169 | return sym ? (void *)sym->value : NULL; |
1da177e4 LT |
2170 | } |
2171 | EXPORT_SYMBOL_GPL(__symbol_get); | |
2172 | ||
eea8b54d AN |
2173 | /* |
2174 | * Ensure that an exported symbol [global namespace] does not already exist | |
02a3e59a | 2175 | * in the kernel or in some other module's exported symbol table. |
be593f4c RR |
2176 | * |
2177 | * You must hold the module_mutex. | |
eea8b54d AN |
2178 | */ |
2179 | static int verify_export_symbols(struct module *mod) | |
2180 | { | |
b211104d | 2181 | unsigned int i; |
eea8b54d | 2182 | struct module *owner; |
b211104d RR |
2183 | const struct kernel_symbol *s; |
2184 | struct { | |
2185 | const struct kernel_symbol *sym; | |
2186 | unsigned int num; | |
2187 | } arr[] = { | |
2188 | { mod->syms, mod->num_syms }, | |
2189 | { mod->gpl_syms, mod->num_gpl_syms }, | |
2190 | { mod->gpl_future_syms, mod->num_gpl_future_syms }, | |
f7f5b675 | 2191 | #ifdef CONFIG_UNUSED_SYMBOLS |
b211104d RR |
2192 | { mod->unused_syms, mod->num_unused_syms }, |
2193 | { mod->unused_gpl_syms, mod->num_unused_gpl_syms }, | |
f7f5b675 | 2194 | #endif |
b211104d | 2195 | }; |
eea8b54d | 2196 | |
b211104d RR |
2197 | for (i = 0; i < ARRAY_SIZE(arr); i++) { |
2198 | for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) { | |
be593f4c | 2199 | if (find_symbol(s->name, &owner, NULL, true, false)) { |
bddb12b3 | 2200 | pr_err("%s: exports duplicate symbol %s" |
b211104d RR |
2201 | " (owned by %s)\n", |
2202 | mod->name, s->name, module_name(owner)); | |
2203 | return -ENOEXEC; | |
2204 | } | |
eea8b54d | 2205 | } |
b211104d RR |
2206 | } |
2207 | return 0; | |
eea8b54d AN |
2208 | } |
2209 | ||
9a4b9708 | 2210 | /* Change all symbols so that st_value encodes the pointer directly. */ |
49668688 RR |
2211 | static int simplify_symbols(struct module *mod, const struct load_info *info) |
2212 | { | |
2213 | Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; | |
2214 | Elf_Sym *sym = (void *)symsec->sh_addr; | |
1da177e4 | 2215 | unsigned long secbase; |
49668688 | 2216 | unsigned int i; |
1da177e4 | 2217 | int ret = 0; |
414fd31b | 2218 | const struct kernel_symbol *ksym; |
1da177e4 | 2219 | |
49668688 RR |
2220 | for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) { |
2221 | const char *name = info->strtab + sym[i].st_name; | |
2222 | ||
1da177e4 LT |
2223 | switch (sym[i].st_shndx) { |
2224 | case SHN_COMMON: | |
80375980 JM |
2225 | /* Ignore common symbols */ |
2226 | if (!strncmp(name, "__gnu_lto", 9)) | |
2227 | break; | |
2228 | ||
1da177e4 LT |
2229 | /* We compiled with -fno-common. These are not |
2230 | supposed to happen. */ | |
5e124169 | 2231 | pr_debug("Common symbol: %s\n", name); |
6da0b565 | 2232 | pr_warn("%s: please compile with -fno-common\n", |
1da177e4 LT |
2233 | mod->name); |
2234 | ret = -ENOEXEC; | |
2235 | break; | |
2236 | ||
2237 | case SHN_ABS: | |
2238 | /* Don't need to do anything */ | |
5e124169 | 2239 | pr_debug("Absolute symbol: 0x%08lx\n", |
1da177e4 LT |
2240 | (long)sym[i].st_value); |
2241 | break; | |
2242 | ||
1ce15ef4 JY |
2243 | case SHN_LIVEPATCH: |
2244 | /* Livepatch symbols are resolved by livepatch */ | |
2245 | break; | |
2246 | ||
1da177e4 | 2247 | case SHN_UNDEF: |
49668688 | 2248 | ksym = resolve_symbol_wait(mod, info, name); |
1da177e4 | 2249 | /* Ok if resolved. */ |
9bea7f23 | 2250 | if (ksym && !IS_ERR(ksym)) { |
414fd31b | 2251 | sym[i].st_value = ksym->value; |
1da177e4 | 2252 | break; |
414fd31b TA |
2253 | } |
2254 | ||
1da177e4 | 2255 | /* Ok if weak. */ |
9bea7f23 | 2256 | if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK) |
1da177e4 LT |
2257 | break; |
2258 | ||
bddb12b3 AM |
2259 | pr_warn("%s: Unknown symbol %s (err %li)\n", |
2260 | mod->name, name, PTR_ERR(ksym)); | |
9bea7f23 | 2261 | ret = PTR_ERR(ksym) ?: -ENOENT; |
1da177e4 LT |
2262 | break; |
2263 | ||
2264 | default: | |
2265 | /* Divert to percpu allocation if a percpu var. */ | |
49668688 | 2266 | if (sym[i].st_shndx == info->index.pcpu) |
259354de | 2267 | secbase = (unsigned long)mod_percpu(mod); |
1da177e4 | 2268 | else |
49668688 | 2269 | secbase = info->sechdrs[sym[i].st_shndx].sh_addr; |
1da177e4 LT |
2270 | sym[i].st_value += secbase; |
2271 | break; | |
2272 | } | |
2273 | } | |
2274 | ||
2275 | return ret; | |
2276 | } | |
2277 | ||
49668688 | 2278 | static int apply_relocations(struct module *mod, const struct load_info *info) |
22e268eb RR |
2279 | { |
2280 | unsigned int i; | |
2281 | int err = 0; | |
2282 | ||
2283 | /* Now do relocations. */ | |
49668688 RR |
2284 | for (i = 1; i < info->hdr->e_shnum; i++) { |
2285 | unsigned int infosec = info->sechdrs[i].sh_info; | |
22e268eb RR |
2286 | |
2287 | /* Not a valid relocation section? */ | |
49668688 | 2288 | if (infosec >= info->hdr->e_shnum) |
22e268eb RR |
2289 | continue; |
2290 | ||
2291 | /* Don't bother with non-allocated sections */ | |
49668688 | 2292 | if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC)) |
22e268eb RR |
2293 | continue; |
2294 | ||
1ce15ef4 JY |
2295 | /* Livepatch relocation sections are applied by livepatch */ |
2296 | if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH) | |
2297 | continue; | |
2298 | ||
49668688 RR |
2299 | if (info->sechdrs[i].sh_type == SHT_REL) |
2300 | err = apply_relocate(info->sechdrs, info->strtab, | |
2301 | info->index.sym, i, mod); | |
2302 | else if (info->sechdrs[i].sh_type == SHT_RELA) | |
2303 | err = apply_relocate_add(info->sechdrs, info->strtab, | |
2304 | info->index.sym, i, mod); | |
22e268eb RR |
2305 | if (err < 0) |
2306 | break; | |
2307 | } | |
2308 | return err; | |
2309 | } | |
2310 | ||
088af9a6 HD |
2311 | /* Additional bytes needed by arch in front of individual sections */ |
2312 | unsigned int __weak arch_mod_section_prepend(struct module *mod, | |
2313 | unsigned int section) | |
2314 | { | |
2315 | /* default implementation just returns zero */ | |
2316 | return 0; | |
2317 | } | |
2318 | ||
1da177e4 | 2319 | /* Update size with this section: return offset. */ |
088af9a6 HD |
2320 | static long get_offset(struct module *mod, unsigned int *size, |
2321 | Elf_Shdr *sechdr, unsigned int section) | |
1da177e4 LT |
2322 | { |
2323 | long ret; | |
2324 | ||
088af9a6 | 2325 | *size += arch_mod_section_prepend(mod, section); |
1da177e4 LT |
2326 | ret = ALIGN(*size, sechdr->sh_addralign ?: 1); |
2327 | *size = ret + sechdr->sh_size; | |
2328 | return ret; | |
2329 | } | |
2330 | ||
2331 | /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld | |
2332 | might -- code, read-only data, read-write data, small data. Tally | |
2333 | sizes, and place the offsets into sh_entsize fields: high bit means it | |
2334 | belongs in init. */ | |
49668688 | 2335 | static void layout_sections(struct module *mod, struct load_info *info) |
1da177e4 LT |
2336 | { |
2337 | static unsigned long const masks[][2] = { | |
2338 | /* NOTE: all executable code must be the first section | |
2339 | * in this array; otherwise modify the text_size | |
2340 | * finder in the two loops below */ | |
2341 | { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL }, | |
2342 | { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL }, | |
444d13ff | 2343 | { SHF_RO_AFTER_INIT | SHF_ALLOC, ARCH_SHF_SMALL }, |
1da177e4 LT |
2344 | { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL }, |
2345 | { ARCH_SHF_SMALL | SHF_ALLOC, 0 } | |
2346 | }; | |
2347 | unsigned int m, i; | |
2348 | ||
49668688 RR |
2349 | for (i = 0; i < info->hdr->e_shnum; i++) |
2350 | info->sechdrs[i].sh_entsize = ~0UL; | |
1da177e4 | 2351 | |
5e124169 | 2352 | pr_debug("Core section allocation order:\n"); |
1da177e4 | 2353 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { |
49668688 RR |
2354 | for (i = 0; i < info->hdr->e_shnum; ++i) { |
2355 | Elf_Shdr *s = &info->sechdrs[i]; | |
2356 | const char *sname = info->secstrings + s->sh_name; | |
1da177e4 LT |
2357 | |
2358 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
2359 | || (s->sh_flags & masks[m][1]) | |
2360 | || s->sh_entsize != ~0UL | |
49668688 | 2361 | || strstarts(sname, ".init")) |
1da177e4 | 2362 | continue; |
7523e4dc | 2363 | s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i); |
5e124169 | 2364 | pr_debug("\t%s\n", sname); |
1da177e4 | 2365 | } |
84e1c6bb MC |
2366 | switch (m) { |
2367 | case 0: /* executable */ | |
7523e4dc RR |
2368 | mod->core_layout.size = debug_align(mod->core_layout.size); |
2369 | mod->core_layout.text_size = mod->core_layout.size; | |
84e1c6bb MC |
2370 | break; |
2371 | case 1: /* RO: text and ro-data */ | |
7523e4dc RR |
2372 | mod->core_layout.size = debug_align(mod->core_layout.size); |
2373 | mod->core_layout.ro_size = mod->core_layout.size; | |
84e1c6bb | 2374 | break; |
444d13ff JY |
2375 | case 2: /* RO after init */ |
2376 | mod->core_layout.size = debug_align(mod->core_layout.size); | |
2377 | mod->core_layout.ro_after_init_size = mod->core_layout.size; | |
2378 | break; | |
2379 | case 4: /* whole core */ | |
7523e4dc | 2380 | mod->core_layout.size = debug_align(mod->core_layout.size); |
84e1c6bb MC |
2381 | break; |
2382 | } | |
1da177e4 LT |
2383 | } |
2384 | ||
5e124169 | 2385 | pr_debug("Init section allocation order:\n"); |
1da177e4 | 2386 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { |
49668688 RR |
2387 | for (i = 0; i < info->hdr->e_shnum; ++i) { |
2388 | Elf_Shdr *s = &info->sechdrs[i]; | |
2389 | const char *sname = info->secstrings + s->sh_name; | |
1da177e4 LT |
2390 | |
2391 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
2392 | || (s->sh_flags & masks[m][1]) | |
2393 | || s->sh_entsize != ~0UL | |
49668688 | 2394 | || !strstarts(sname, ".init")) |
1da177e4 | 2395 | continue; |
7523e4dc | 2396 | s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i) |
1da177e4 | 2397 | | INIT_OFFSET_MASK); |
5e124169 | 2398 | pr_debug("\t%s\n", sname); |
1da177e4 | 2399 | } |
84e1c6bb MC |
2400 | switch (m) { |
2401 | case 0: /* executable */ | |
7523e4dc RR |
2402 | mod->init_layout.size = debug_align(mod->init_layout.size); |
2403 | mod->init_layout.text_size = mod->init_layout.size; | |
84e1c6bb MC |
2404 | break; |
2405 | case 1: /* RO: text and ro-data */ | |
7523e4dc RR |
2406 | mod->init_layout.size = debug_align(mod->init_layout.size); |
2407 | mod->init_layout.ro_size = mod->init_layout.size; | |
84e1c6bb | 2408 | break; |
444d13ff JY |
2409 | case 2: |
2410 | /* | |
2411 | * RO after init doesn't apply to init_layout (only | |
2412 | * core_layout), so it just takes the value of ro_size. | |
2413 | */ | |
2414 | mod->init_layout.ro_after_init_size = mod->init_layout.ro_size; | |
2415 | break; | |
2416 | case 4: /* whole init */ | |
7523e4dc | 2417 | mod->init_layout.size = debug_align(mod->init_layout.size); |
84e1c6bb MC |
2418 | break; |
2419 | } | |
1da177e4 LT |
2420 | } |
2421 | } | |
2422 | ||
1da177e4 LT |
2423 | static void set_license(struct module *mod, const char *license) |
2424 | { | |
2425 | if (!license) | |
2426 | license = "unspecified"; | |
2427 | ||
fa3ba2e8 | 2428 | if (!license_is_gpl_compatible(license)) { |
25ddbb18 | 2429 | if (!test_taint(TAINT_PROPRIETARY_MODULE)) |
bddb12b3 AM |
2430 | pr_warn("%s: module license '%s' taints kernel.\n", |
2431 | mod->name, license); | |
373d4d09 RR |
2432 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
2433 | LOCKDEP_NOW_UNRELIABLE); | |
1da177e4 LT |
2434 | } |
2435 | } | |
2436 | ||
2437 | /* Parse tag=value strings from .modinfo section */ | |
2438 | static char *next_string(char *string, unsigned long *secsize) | |
2439 | { | |
2440 | /* Skip non-zero chars */ | |
2441 | while (string[0]) { | |
2442 | string++; | |
2443 | if ((*secsize)-- <= 1) | |
2444 | return NULL; | |
2445 | } | |
2446 | ||
2447 | /* Skip any zero padding. */ | |
2448 | while (!string[0]) { | |
2449 | string++; | |
2450 | if ((*secsize)-- <= 1) | |
2451 | return NULL; | |
2452 | } | |
2453 | return string; | |
2454 | } | |
2455 | ||
49668688 | 2456 | static char *get_modinfo(struct load_info *info, const char *tag) |
1da177e4 LT |
2457 | { |
2458 | char *p; | |
2459 | unsigned int taglen = strlen(tag); | |
49668688 RR |
2460 | Elf_Shdr *infosec = &info->sechdrs[info->index.info]; |
2461 | unsigned long size = infosec->sh_size; | |
1da177e4 | 2462 | |
49668688 | 2463 | for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) { |
1da177e4 LT |
2464 | if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') |
2465 | return p + taglen + 1; | |
2466 | } | |
2467 | return NULL; | |
2468 | } | |
2469 | ||
49668688 | 2470 | static void setup_modinfo(struct module *mod, struct load_info *info) |
c988d2b2 MD |
2471 | { |
2472 | struct module_attribute *attr; | |
2473 | int i; | |
2474 | ||
2475 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
2476 | if (attr->setup) | |
49668688 | 2477 | attr->setup(mod, get_modinfo(info, attr->attr.name)); |
c988d2b2 MD |
2478 | } |
2479 | } | |
c988d2b2 | 2480 | |
a263f776 RR |
2481 | static void free_modinfo(struct module *mod) |
2482 | { | |
2483 | struct module_attribute *attr; | |
2484 | int i; | |
2485 | ||
2486 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
2487 | if (attr->free) | |
2488 | attr->free(mod); | |
2489 | } | |
2490 | } | |
2491 | ||
1da177e4 | 2492 | #ifdef CONFIG_KALLSYMS |
15bba37d WC |
2493 | |
2494 | /* lookup symbol in given range of kernel_symbols */ | |
2495 | static const struct kernel_symbol *lookup_symbol(const char *name, | |
2496 | const struct kernel_symbol *start, | |
2497 | const struct kernel_symbol *stop) | |
2498 | { | |
9d63487f AIB |
2499 | return bsearch(name, start, stop - start, |
2500 | sizeof(struct kernel_symbol), cmp_name); | |
15bba37d WC |
2501 | } |
2502 | ||
ca4787b7 TA |
2503 | static int is_exported(const char *name, unsigned long value, |
2504 | const struct module *mod) | |
1da177e4 | 2505 | { |
ca4787b7 TA |
2506 | const struct kernel_symbol *ks; |
2507 | if (!mod) | |
2508 | ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab); | |
3fd6805f | 2509 | else |
ca4787b7 TA |
2510 | ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms); |
2511 | return ks != NULL && ks->value == value; | |
1da177e4 LT |
2512 | } |
2513 | ||
2514 | /* As per nm */ | |
eded41c1 | 2515 | static char elf_type(const Elf_Sym *sym, const struct load_info *info) |
1da177e4 | 2516 | { |
eded41c1 RR |
2517 | const Elf_Shdr *sechdrs = info->sechdrs; |
2518 | ||
1da177e4 LT |
2519 | if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { |
2520 | if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) | |
2521 | return 'v'; | |
2522 | else | |
2523 | return 'w'; | |
2524 | } | |
2525 | if (sym->st_shndx == SHN_UNDEF) | |
2526 | return 'U'; | |
e0224418 | 2527 | if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu) |
1da177e4 LT |
2528 | return 'a'; |
2529 | if (sym->st_shndx >= SHN_LORESERVE) | |
2530 | return '?'; | |
2531 | if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) | |
2532 | return 't'; | |
2533 | if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC | |
2534 | && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { | |
2535 | if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) | |
2536 | return 'r'; | |
2537 | else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
2538 | return 'g'; | |
2539 | else | |
2540 | return 'd'; | |
2541 | } | |
2542 | if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { | |
2543 | if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
2544 | return 's'; | |
2545 | else | |
2546 | return 'b'; | |
2547 | } | |
eded41c1 RR |
2548 | if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name, |
2549 | ".debug")) { | |
1da177e4 | 2550 | return 'n'; |
eded41c1 | 2551 | } |
1da177e4 LT |
2552 | return '?'; |
2553 | } | |
2554 | ||
4a496226 | 2555 | static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs, |
e0224418 | 2556 | unsigned int shnum, unsigned int pcpundx) |
4a496226 JB |
2557 | { |
2558 | const Elf_Shdr *sec; | |
2559 | ||
2560 | if (src->st_shndx == SHN_UNDEF | |
2561 | || src->st_shndx >= shnum | |
2562 | || !src->st_name) | |
2563 | return false; | |
2564 | ||
e0224418 MB |
2565 | #ifdef CONFIG_KALLSYMS_ALL |
2566 | if (src->st_shndx == pcpundx) | |
2567 | return true; | |
2568 | #endif | |
2569 | ||
4a496226 JB |
2570 | sec = sechdrs + src->st_shndx; |
2571 | if (!(sec->sh_flags & SHF_ALLOC) | |
2572 | #ifndef CONFIG_KALLSYMS_ALL | |
2573 | || !(sec->sh_flags & SHF_EXECINSTR) | |
2574 | #endif | |
2575 | || (sec->sh_entsize & INIT_OFFSET_MASK)) | |
2576 | return false; | |
2577 | ||
2578 | return true; | |
2579 | } | |
2580 | ||
48fd1188 KC |
2581 | /* |
2582 | * We only allocate and copy the strings needed by the parts of symtab | |
2583 | * we keep. This is simple, but has the effect of making multiple | |
2584 | * copies of duplicates. We could be more sophisticated, see | |
2585 | * linux-kernel thread starting with | |
2586 | * <73defb5e4bca04a6431392cc341112b1@localhost>. | |
2587 | */ | |
49668688 | 2588 | static void layout_symtab(struct module *mod, struct load_info *info) |
4a496226 | 2589 | { |
49668688 RR |
2590 | Elf_Shdr *symsect = info->sechdrs + info->index.sym; |
2591 | Elf_Shdr *strsect = info->sechdrs + info->index.str; | |
4a496226 | 2592 | const Elf_Sym *src; |
54523ec7 | 2593 | unsigned int i, nsrc, ndst, strtab_size = 0; |
4a496226 JB |
2594 | |
2595 | /* Put symbol section at end of init part of module. */ | |
2596 | symsect->sh_flags |= SHF_ALLOC; | |
7523e4dc | 2597 | symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect, |
49668688 | 2598 | info->index.sym) | INIT_OFFSET_MASK; |
5e124169 | 2599 | pr_debug("\t%s\n", info->secstrings + symsect->sh_name); |
4a496226 | 2600 | |
49668688 | 2601 | src = (void *)info->hdr + symsect->sh_offset; |
4a496226 | 2602 | nsrc = symsect->sh_size / sizeof(*src); |
70b1e916 | 2603 | |
48fd1188 | 2604 | /* Compute total space required for the core symbols' strtab. */ |
59ef28b1 | 2605 | for (ndst = i = 0; i < nsrc; i++) { |
1ce15ef4 | 2606 | if (i == 0 || is_livepatch_module(mod) || |
e0224418 MB |
2607 | is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, |
2608 | info->index.pcpu)) { | |
59ef28b1 | 2609 | strtab_size += strlen(&info->strtab[src[i].st_name])+1; |
48fd1188 | 2610 | ndst++; |
554bdfe5 | 2611 | } |
59ef28b1 | 2612 | } |
4a496226 JB |
2613 | |
2614 | /* Append room for core symbols at end of core part. */ | |
7523e4dc RR |
2615 | info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1); |
2616 | info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym); | |
2617 | mod->core_layout.size += strtab_size; | |
2618 | mod->core_layout.size = debug_align(mod->core_layout.size); | |
4a496226 | 2619 | |
554bdfe5 JB |
2620 | /* Put string table section at end of init part of module. */ |
2621 | strsect->sh_flags |= SHF_ALLOC; | |
7523e4dc | 2622 | strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect, |
49668688 | 2623 | info->index.str) | INIT_OFFSET_MASK; |
5e124169 | 2624 | pr_debug("\t%s\n", info->secstrings + strsect->sh_name); |
8244062e RR |
2625 | |
2626 | /* We'll tack temporary mod_kallsyms on the end. */ | |
2627 | mod->init_layout.size = ALIGN(mod->init_layout.size, | |
2628 | __alignof__(struct mod_kallsyms)); | |
2629 | info->mod_kallsyms_init_off = mod->init_layout.size; | |
2630 | mod->init_layout.size += sizeof(struct mod_kallsyms); | |
2631 | mod->init_layout.size = debug_align(mod->init_layout.size); | |
4a496226 JB |
2632 | } |
2633 | ||
8244062e RR |
2634 | /* |
2635 | * We use the full symtab and strtab which layout_symtab arranged to | |
2636 | * be appended to the init section. Later we switch to the cut-down | |
2637 | * core-only ones. | |
2638 | */ | |
811d66a0 | 2639 | static void add_kallsyms(struct module *mod, const struct load_info *info) |
1da177e4 | 2640 | { |
4a496226 JB |
2641 | unsigned int i, ndst; |
2642 | const Elf_Sym *src; | |
2643 | Elf_Sym *dst; | |
554bdfe5 | 2644 | char *s; |
eded41c1 | 2645 | Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; |
1da177e4 | 2646 | |
8244062e RR |
2647 | /* Set up to point into init section. */ |
2648 | mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off; | |
2649 | ||
2650 | mod->kallsyms->symtab = (void *)symsec->sh_addr; | |
2651 | mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym); | |
511ca6ae | 2652 | /* Make sure we get permanent strtab: don't use info->strtab. */ |
8244062e | 2653 | mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr; |
1da177e4 LT |
2654 | |
2655 | /* Set types up while we still have access to sections. */ | |
8244062e RR |
2656 | for (i = 0; i < mod->kallsyms->num_symtab; i++) |
2657 | mod->kallsyms->symtab[i].st_info | |
2658 | = elf_type(&mod->kallsyms->symtab[i], info); | |
2659 | ||
2660 | /* Now populate the cut down core kallsyms for after init. */ | |
2661 | mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs; | |
2662 | mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs; | |
2663 | src = mod->kallsyms->symtab; | |
2664 | for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) { | |
1ce15ef4 | 2665 | if (i == 0 || is_livepatch_module(mod) || |
e0224418 MB |
2666 | is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, |
2667 | info->index.pcpu)) { | |
59ef28b1 | 2668 | dst[ndst] = src[i]; |
8244062e RR |
2669 | dst[ndst++].st_name = s - mod->core_kallsyms.strtab; |
2670 | s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name], | |
59ef28b1 RR |
2671 | KSYM_NAME_LEN) + 1; |
2672 | } | |
4a496226 | 2673 | } |
8244062e | 2674 | mod->core_kallsyms.num_symtab = ndst; |
1da177e4 LT |
2675 | } |
2676 | #else | |
49668688 | 2677 | static inline void layout_symtab(struct module *mod, struct load_info *info) |
4a496226 JB |
2678 | { |
2679 | } | |
3ae91c21 | 2680 | |
abbce906 | 2681 | static void add_kallsyms(struct module *mod, const struct load_info *info) |
1da177e4 LT |
2682 | { |
2683 | } | |
2684 | #endif /* CONFIG_KALLSYMS */ | |
2685 | ||
e9d376f0 | 2686 | static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num) |
346e15be | 2687 | { |
811d66a0 RR |
2688 | if (!debug) |
2689 | return; | |
e9d376f0 JB |
2690 | #ifdef CONFIG_DYNAMIC_DEBUG |
2691 | if (ddebug_add_module(debug, num, debug->modname)) | |
bddb12b3 AM |
2692 | pr_err("dynamic debug error adding module: %s\n", |
2693 | debug->modname); | |
e9d376f0 | 2694 | #endif |
5e458cc0 | 2695 | } |
346e15be | 2696 | |
ff49d74a YS |
2697 | static void dynamic_debug_remove(struct _ddebug *debug) |
2698 | { | |
2699 | if (debug) | |
2700 | ddebug_remove_module(debug->modname); | |
2701 | } | |
2702 | ||
74e08fcf JB |
2703 | void * __weak module_alloc(unsigned long size) |
2704 | { | |
82fab442 | 2705 | return vmalloc_exec(size); |
74e08fcf JB |
2706 | } |
2707 | ||
4f2294b6 | 2708 | #ifdef CONFIG_DEBUG_KMEMLEAK |
49668688 RR |
2709 | static void kmemleak_load_module(const struct module *mod, |
2710 | const struct load_info *info) | |
4f2294b6 CM |
2711 | { |
2712 | unsigned int i; | |
2713 | ||
2714 | /* only scan the sections containing data */ | |
c017b4be | 2715 | kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL); |
4f2294b6 | 2716 | |
49668688 | 2717 | for (i = 1; i < info->hdr->e_shnum; i++) { |
06c9494c SR |
2718 | /* Scan all writable sections that's not executable */ |
2719 | if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) || | |
2720 | !(info->sechdrs[i].sh_flags & SHF_WRITE) || | |
2721 | (info->sechdrs[i].sh_flags & SHF_EXECINSTR)) | |
4f2294b6 CM |
2722 | continue; |
2723 | ||
49668688 RR |
2724 | kmemleak_scan_area((void *)info->sechdrs[i].sh_addr, |
2725 | info->sechdrs[i].sh_size, GFP_KERNEL); | |
4f2294b6 CM |
2726 | } |
2727 | } | |
2728 | #else | |
49668688 RR |
2729 | static inline void kmemleak_load_module(const struct module *mod, |
2730 | const struct load_info *info) | |
4f2294b6 CM |
2731 | { |
2732 | } | |
2733 | #endif | |
2734 | ||
106a4ee2 | 2735 | #ifdef CONFIG_MODULE_SIG |
bca014ca | 2736 | static int module_sig_check(struct load_info *info, int flags) |
106a4ee2 RR |
2737 | { |
2738 | int err = -ENOKEY; | |
34e1169d KC |
2739 | const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; |
2740 | const void *mod = info->hdr; | |
caabe240 | 2741 | |
bca014ca BH |
2742 | /* |
2743 | * Require flags == 0, as a module with version information | |
2744 | * removed is no longer the module that was signed | |
2745 | */ | |
2746 | if (flags == 0 && | |
2747 | info->len > markerlen && | |
34e1169d | 2748 | memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) { |
caabe240 | 2749 | /* We truncate the module to discard the signature */ |
34e1169d KC |
2750 | info->len -= markerlen; |
2751 | err = mod_verify_sig(mod, &info->len); | |
106a4ee2 RR |
2752 | } |
2753 | ||
2754 | if (!err) { | |
2755 | info->sig_ok = true; | |
2756 | return 0; | |
2757 | } | |
2758 | ||
2759 | /* Not having a signature is only an error if we're strict. */ | |
2760 | if (err == -ENOKEY && !sig_enforce) | |
2761 | err = 0; | |
2762 | ||
2763 | return err; | |
2764 | } | |
2765 | #else /* !CONFIG_MODULE_SIG */ | |
bca014ca | 2766 | static int module_sig_check(struct load_info *info, int flags) |
106a4ee2 RR |
2767 | { |
2768 | return 0; | |
2769 | } | |
2770 | #endif /* !CONFIG_MODULE_SIG */ | |
2771 | ||
34e1169d KC |
2772 | /* Sanity checks against invalid binaries, wrong arch, weird elf version. */ |
2773 | static int elf_header_check(struct load_info *info) | |
40dd2560 | 2774 | { |
34e1169d KC |
2775 | if (info->len < sizeof(*(info->hdr))) |
2776 | return -ENOEXEC; | |
2777 | ||
2778 | if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0 | |
2779 | || info->hdr->e_type != ET_REL | |
2780 | || !elf_check_arch(info->hdr) | |
2781 | || info->hdr->e_shentsize != sizeof(Elf_Shdr)) | |
2782 | return -ENOEXEC; | |
2783 | ||
2784 | if (info->hdr->e_shoff >= info->len | |
2785 | || (info->hdr->e_shnum * sizeof(Elf_Shdr) > | |
2786 | info->len - info->hdr->e_shoff)) | |
2787 | return -ENOEXEC; | |
40dd2560 | 2788 | |
34e1169d KC |
2789 | return 0; |
2790 | } | |
2791 | ||
3afe9f84 LT |
2792 | #define COPY_CHUNK_SIZE (16*PAGE_SIZE) |
2793 | ||
2794 | static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len) | |
2795 | { | |
2796 | do { | |
2797 | unsigned long n = min(len, COPY_CHUNK_SIZE); | |
2798 | ||
2799 | if (copy_from_user(dst, usrc, n) != 0) | |
2800 | return -EFAULT; | |
2801 | cond_resched(); | |
2802 | dst += n; | |
2803 | usrc += n; | |
2804 | len -= n; | |
2805 | } while (len); | |
2806 | return 0; | |
2807 | } | |
2808 | ||
1ce15ef4 | 2809 | #ifdef CONFIG_LIVEPATCH |
2992ef29 | 2810 | static int check_modinfo_livepatch(struct module *mod, struct load_info *info) |
1ce15ef4 | 2811 | { |
2992ef29 JP |
2812 | if (get_modinfo(info, "livepatch")) { |
2813 | mod->klp = true; | |
2814 | add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK); | |
2815 | } | |
1ce15ef4 JY |
2816 | |
2817 | return 0; | |
2818 | } | |
2819 | #else /* !CONFIG_LIVEPATCH */ | |
2992ef29 | 2820 | static int check_modinfo_livepatch(struct module *mod, struct load_info *info) |
1ce15ef4 JY |
2821 | { |
2822 | if (get_modinfo(info, "livepatch")) { | |
2823 | pr_err("%s: module is marked as livepatch module, but livepatch support is disabled", | |
2824 | mod->name); | |
2825 | return -ENOEXEC; | |
2826 | } | |
2827 | ||
2828 | return 0; | |
2829 | } | |
2830 | #endif /* CONFIG_LIVEPATCH */ | |
2831 | ||
34e1169d KC |
2832 | /* Sets info->hdr and info->len. */ |
2833 | static int copy_module_from_user(const void __user *umod, unsigned long len, | |
2834 | struct load_info *info) | |
40dd2560 RR |
2835 | { |
2836 | int err; | |
40dd2560 | 2837 | |
34e1169d KC |
2838 | info->len = len; |
2839 | if (info->len < sizeof(*(info->hdr))) | |
40dd2560 RR |
2840 | return -ENOEXEC; |
2841 | ||
a1db7420 | 2842 | err = security_kernel_read_file(NULL, READING_MODULE); |
2e72d51b KC |
2843 | if (err) |
2844 | return err; | |
2845 | ||
40dd2560 | 2846 | /* Suck in entire file: we'll want most of it. */ |
cc9e605d KS |
2847 | info->hdr = __vmalloc(info->len, |
2848 | GFP_KERNEL | __GFP_HIGHMEM | __GFP_NOWARN, PAGE_KERNEL); | |
34e1169d | 2849 | if (!info->hdr) |
40dd2560 RR |
2850 | return -ENOMEM; |
2851 | ||
3afe9f84 | 2852 | if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) { |
34e1169d KC |
2853 | vfree(info->hdr); |
2854 | return -EFAULT; | |
40dd2560 RR |
2855 | } |
2856 | ||
34e1169d KC |
2857 | return 0; |
2858 | } | |
2859 | ||
d913188c RR |
2860 | static void free_copy(struct load_info *info) |
2861 | { | |
d913188c RR |
2862 | vfree(info->hdr); |
2863 | } | |
2864 | ||
2f3238ae | 2865 | static int rewrite_section_headers(struct load_info *info, int flags) |
8b5f61a7 RR |
2866 | { |
2867 | unsigned int i; | |
2868 | ||
2869 | /* This should always be true, but let's be sure. */ | |
2870 | info->sechdrs[0].sh_addr = 0; | |
2871 | ||
2872 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
2873 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
2874 | if (shdr->sh_type != SHT_NOBITS | |
2875 | && info->len < shdr->sh_offset + shdr->sh_size) { | |
bddb12b3 | 2876 | pr_err("Module len %lu truncated\n", info->len); |
8b5f61a7 RR |
2877 | return -ENOEXEC; |
2878 | } | |
2879 | ||
2880 | /* Mark all sections sh_addr with their address in the | |
2881 | temporary image. */ | |
2882 | shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset; | |
2883 | ||
2884 | #ifndef CONFIG_MODULE_UNLOAD | |
2885 | /* Don't load .exit sections */ | |
2886 | if (strstarts(info->secstrings+shdr->sh_name, ".exit")) | |
2887 | shdr->sh_flags &= ~(unsigned long)SHF_ALLOC; | |
2888 | #endif | |
8b5f61a7 | 2889 | } |
d6df72a0 RR |
2890 | |
2891 | /* Track but don't keep modinfo and version sections. */ | |
2f3238ae RR |
2892 | if (flags & MODULE_INIT_IGNORE_MODVERSIONS) |
2893 | info->index.vers = 0; /* Pretend no __versions section! */ | |
2894 | else | |
2895 | info->index.vers = find_sec(info, "__versions"); | |
49668688 | 2896 | info->index.info = find_sec(info, ".modinfo"); |
d6df72a0 RR |
2897 | info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC; |
2898 | info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
8b5f61a7 RR |
2899 | return 0; |
2900 | } | |
2901 | ||
3264d3f9 LT |
2902 | /* |
2903 | * Set up our basic convenience variables (pointers to section headers, | |
2904 | * search for module section index etc), and do some basic section | |
2905 | * verification. | |
2906 | * | |
2907 | * Return the temporary module pointer (we'll replace it with the final | |
2908 | * one when we move the module sections around). | |
2909 | */ | |
2f3238ae | 2910 | static struct module *setup_load_info(struct load_info *info, int flags) |
3264d3f9 LT |
2911 | { |
2912 | unsigned int i; | |
8b5f61a7 | 2913 | int err; |
3264d3f9 LT |
2914 | struct module *mod; |
2915 | ||
2916 | /* Set up the convenience variables */ | |
2917 | info->sechdrs = (void *)info->hdr + info->hdr->e_shoff; | |
8b5f61a7 RR |
2918 | info->secstrings = (void *)info->hdr |
2919 | + info->sechdrs[info->hdr->e_shstrndx].sh_offset; | |
3264d3f9 | 2920 | |
2f3238ae | 2921 | err = rewrite_section_headers(info, flags); |
8b5f61a7 RR |
2922 | if (err) |
2923 | return ERR_PTR(err); | |
3264d3f9 | 2924 | |
8b5f61a7 RR |
2925 | /* Find internal symbols and strings. */ |
2926 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
3264d3f9 LT |
2927 | if (info->sechdrs[i].sh_type == SHT_SYMTAB) { |
2928 | info->index.sym = i; | |
2929 | info->index.str = info->sechdrs[i].sh_link; | |
8b5f61a7 RR |
2930 | info->strtab = (char *)info->hdr |
2931 | + info->sechdrs[info->index.str].sh_offset; | |
2932 | break; | |
3264d3f9 | 2933 | } |
3264d3f9 LT |
2934 | } |
2935 | ||
49668688 | 2936 | info->index.mod = find_sec(info, ".gnu.linkonce.this_module"); |
3264d3f9 | 2937 | if (!info->index.mod) { |
bddb12b3 | 2938 | pr_warn("No module found in object\n"); |
3264d3f9 LT |
2939 | return ERR_PTR(-ENOEXEC); |
2940 | } | |
2941 | /* This is temporary: point mod into copy of data. */ | |
2942 | mod = (void *)info->sechdrs[info->index.mod].sh_addr; | |
2943 | ||
2944 | if (info->index.sym == 0) { | |
bddb12b3 | 2945 | pr_warn("%s: module has no symbols (stripped?)\n", mod->name); |
3264d3f9 LT |
2946 | return ERR_PTR(-ENOEXEC); |
2947 | } | |
2948 | ||
49668688 | 2949 | info->index.pcpu = find_pcpusec(info); |
3264d3f9 | 2950 | |
3264d3f9 LT |
2951 | /* Check module struct version now, before we try to use module. */ |
2952 | if (!check_modstruct_version(info->sechdrs, info->index.vers, mod)) | |
2953 | return ERR_PTR(-ENOEXEC); | |
2954 | ||
2955 | return mod; | |
3264d3f9 LT |
2956 | } |
2957 | ||
2f3238ae | 2958 | static int check_modinfo(struct module *mod, struct load_info *info, int flags) |
40dd2560 | 2959 | { |
49668688 | 2960 | const char *modmagic = get_modinfo(info, "vermagic"); |
40dd2560 RR |
2961 | int err; |
2962 | ||
2f3238ae RR |
2963 | if (flags & MODULE_INIT_IGNORE_VERMAGIC) |
2964 | modmagic = NULL; | |
2965 | ||
40dd2560 RR |
2966 | /* This is allowed: modprobe --force will invalidate it. */ |
2967 | if (!modmagic) { | |
2968 | err = try_to_force_load(mod, "bad vermagic"); | |
2969 | if (err) | |
2970 | return err; | |
49668688 | 2971 | } else if (!same_magic(modmagic, vermagic, info->index.vers)) { |
bddb12b3 | 2972 | pr_err("%s: version magic '%s' should be '%s'\n", |
40dd2560 RR |
2973 | mod->name, modmagic, vermagic); |
2974 | return -ENOEXEC; | |
2975 | } | |
2976 | ||
3205c36c LP |
2977 | if (!get_modinfo(info, "intree")) { |
2978 | if (!test_taint(TAINT_OOT_MODULE)) | |
2979 | pr_warn("%s: loading out-of-tree module taints kernel.\n", | |
2980 | mod->name); | |
373d4d09 | 2981 | add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK); |
3205c36c | 2982 | } |
2449b8ba | 2983 | |
49668688 | 2984 | if (get_modinfo(info, "staging")) { |
373d4d09 | 2985 | add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK); |
bddb12b3 AM |
2986 | pr_warn("%s: module is from the staging directory, the quality " |
2987 | "is unknown, you have been warned.\n", mod->name); | |
40dd2560 | 2988 | } |
22e268eb | 2989 | |
2992ef29 | 2990 | err = check_modinfo_livepatch(mod, info); |
1ce15ef4 JY |
2991 | if (err) |
2992 | return err; | |
2993 | ||
22e268eb | 2994 | /* Set up license info based on the info section */ |
49668688 | 2995 | set_license(mod, get_modinfo(info, "license")); |
22e268eb | 2996 | |
40dd2560 RR |
2997 | return 0; |
2998 | } | |
2999 | ||
eb3057df | 3000 | static int find_module_sections(struct module *mod, struct load_info *info) |
f91a13bb | 3001 | { |
49668688 | 3002 | mod->kp = section_objs(info, "__param", |
f91a13bb | 3003 | sizeof(*mod->kp), &mod->num_kp); |
49668688 | 3004 | mod->syms = section_objs(info, "__ksymtab", |
f91a13bb | 3005 | sizeof(*mod->syms), &mod->num_syms); |
49668688 RR |
3006 | mod->crcs = section_addr(info, "__kcrctab"); |
3007 | mod->gpl_syms = section_objs(info, "__ksymtab_gpl", | |
f91a13bb LT |
3008 | sizeof(*mod->gpl_syms), |
3009 | &mod->num_gpl_syms); | |
49668688 RR |
3010 | mod->gpl_crcs = section_addr(info, "__kcrctab_gpl"); |
3011 | mod->gpl_future_syms = section_objs(info, | |
f91a13bb LT |
3012 | "__ksymtab_gpl_future", |
3013 | sizeof(*mod->gpl_future_syms), | |
3014 | &mod->num_gpl_future_syms); | |
49668688 | 3015 | mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future"); |
f91a13bb LT |
3016 | |
3017 | #ifdef CONFIG_UNUSED_SYMBOLS | |
49668688 | 3018 | mod->unused_syms = section_objs(info, "__ksymtab_unused", |
f91a13bb LT |
3019 | sizeof(*mod->unused_syms), |
3020 | &mod->num_unused_syms); | |
49668688 RR |
3021 | mod->unused_crcs = section_addr(info, "__kcrctab_unused"); |
3022 | mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl", | |
f91a13bb LT |
3023 | sizeof(*mod->unused_gpl_syms), |
3024 | &mod->num_unused_gpl_syms); | |
49668688 | 3025 | mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl"); |
f91a13bb LT |
3026 | #endif |
3027 | #ifdef CONFIG_CONSTRUCTORS | |
49668688 | 3028 | mod->ctors = section_objs(info, ".ctors", |
f91a13bb | 3029 | sizeof(*mod->ctors), &mod->num_ctors); |
eb3057df FH |
3030 | if (!mod->ctors) |
3031 | mod->ctors = section_objs(info, ".init_array", | |
3032 | sizeof(*mod->ctors), &mod->num_ctors); | |
3033 | else if (find_sec(info, ".init_array")) { | |
3034 | /* | |
3035 | * This shouldn't happen with same compiler and binutils | |
3036 | * building all parts of the module. | |
3037 | */ | |
6da0b565 | 3038 | pr_warn("%s: has both .ctors and .init_array.\n", |
eb3057df FH |
3039 | mod->name); |
3040 | return -EINVAL; | |
3041 | } | |
f91a13bb LT |
3042 | #endif |
3043 | ||
3044 | #ifdef CONFIG_TRACEPOINTS | |
65498646 MD |
3045 | mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs", |
3046 | sizeof(*mod->tracepoints_ptrs), | |
3047 | &mod->num_tracepoints); | |
f91a13bb | 3048 | #endif |
bf5438fc JB |
3049 | #ifdef HAVE_JUMP_LABEL |
3050 | mod->jump_entries = section_objs(info, "__jump_table", | |
3051 | sizeof(*mod->jump_entries), | |
3052 | &mod->num_jump_entries); | |
3053 | #endif | |
f91a13bb | 3054 | #ifdef CONFIG_EVENT_TRACING |
49668688 | 3055 | mod->trace_events = section_objs(info, "_ftrace_events", |
f91a13bb LT |
3056 | sizeof(*mod->trace_events), |
3057 | &mod->num_trace_events); | |
3673b8e4 SRRH |
3058 | mod->trace_enums = section_objs(info, "_ftrace_enum_map", |
3059 | sizeof(*mod->trace_enums), | |
3060 | &mod->num_trace_enums); | |
f91a13bb | 3061 | #endif |
13b9b6e7 SR |
3062 | #ifdef CONFIG_TRACING |
3063 | mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt", | |
3064 | sizeof(*mod->trace_bprintk_fmt_start), | |
3065 | &mod->num_trace_bprintk_fmt); | |
13b9b6e7 | 3066 | #endif |
f91a13bb LT |
3067 | #ifdef CONFIG_FTRACE_MCOUNT_RECORD |
3068 | /* sechdrs[0].sh_size is always zero */ | |
49668688 | 3069 | mod->ftrace_callsites = section_objs(info, "__mcount_loc", |
f91a13bb LT |
3070 | sizeof(*mod->ftrace_callsites), |
3071 | &mod->num_ftrace_callsites); | |
3072 | #endif | |
22e268eb | 3073 | |
811d66a0 RR |
3074 | mod->extable = section_objs(info, "__ex_table", |
3075 | sizeof(*mod->extable), &mod->num_exentries); | |
3076 | ||
49668688 | 3077 | if (section_addr(info, "__obsparm")) |
bddb12b3 | 3078 | pr_warn("%s: Ignoring obsolete parameters\n", mod->name); |
811d66a0 RR |
3079 | |
3080 | info->debug = section_objs(info, "__verbose", | |
3081 | sizeof(*info->debug), &info->num_debug); | |
eb3057df FH |
3082 | |
3083 | return 0; | |
f91a13bb LT |
3084 | } |
3085 | ||
49668688 | 3086 | static int move_module(struct module *mod, struct load_info *info) |
65b8a9b4 LT |
3087 | { |
3088 | int i; | |
3089 | void *ptr; | |
3090 | ||
3091 | /* Do the allocs. */ | |
7523e4dc | 3092 | ptr = module_alloc(mod->core_layout.size); |
65b8a9b4 LT |
3093 | /* |
3094 | * The pointer to this block is stored in the module structure | |
3095 | * which is inside the block. Just mark it as not being a | |
3096 | * leak. | |
3097 | */ | |
3098 | kmemleak_not_leak(ptr); | |
3099 | if (!ptr) | |
d913188c | 3100 | return -ENOMEM; |
65b8a9b4 | 3101 | |
7523e4dc RR |
3102 | memset(ptr, 0, mod->core_layout.size); |
3103 | mod->core_layout.base = ptr; | |
65b8a9b4 | 3104 | |
7523e4dc RR |
3105 | if (mod->init_layout.size) { |
3106 | ptr = module_alloc(mod->init_layout.size); | |
82fab442 RR |
3107 | /* |
3108 | * The pointer to this block is stored in the module structure | |
3109 | * which is inside the block. This block doesn't need to be | |
3110 | * scanned as it contains data and code that will be freed | |
3111 | * after the module is initialized. | |
3112 | */ | |
3113 | kmemleak_ignore(ptr); | |
3114 | if (!ptr) { | |
7523e4dc | 3115 | module_memfree(mod->core_layout.base); |
82fab442 RR |
3116 | return -ENOMEM; |
3117 | } | |
7523e4dc RR |
3118 | memset(ptr, 0, mod->init_layout.size); |
3119 | mod->init_layout.base = ptr; | |
82fab442 | 3120 | } else |
7523e4dc | 3121 | mod->init_layout.base = NULL; |
65b8a9b4 LT |
3122 | |
3123 | /* Transfer each section which specifies SHF_ALLOC */ | |
5e124169 | 3124 | pr_debug("final section addresses:\n"); |
49668688 | 3125 | for (i = 0; i < info->hdr->e_shnum; i++) { |
65b8a9b4 | 3126 | void *dest; |
49668688 | 3127 | Elf_Shdr *shdr = &info->sechdrs[i]; |
65b8a9b4 | 3128 | |
49668688 | 3129 | if (!(shdr->sh_flags & SHF_ALLOC)) |
65b8a9b4 LT |
3130 | continue; |
3131 | ||
49668688 | 3132 | if (shdr->sh_entsize & INIT_OFFSET_MASK) |
7523e4dc | 3133 | dest = mod->init_layout.base |
49668688 | 3134 | + (shdr->sh_entsize & ~INIT_OFFSET_MASK); |
65b8a9b4 | 3135 | else |
7523e4dc | 3136 | dest = mod->core_layout.base + shdr->sh_entsize; |
65b8a9b4 | 3137 | |
49668688 RR |
3138 | if (shdr->sh_type != SHT_NOBITS) |
3139 | memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size); | |
65b8a9b4 | 3140 | /* Update sh_addr to point to copy in image. */ |
49668688 | 3141 | shdr->sh_addr = (unsigned long)dest; |
5e124169 JC |
3142 | pr_debug("\t0x%lx %s\n", |
3143 | (long)shdr->sh_addr, info->secstrings + shdr->sh_name); | |
65b8a9b4 | 3144 | } |
d913188c RR |
3145 | |
3146 | return 0; | |
65b8a9b4 LT |
3147 | } |
3148 | ||
49668688 | 3149 | static int check_module_license_and_versions(struct module *mod) |
22e268eb | 3150 | { |
3205c36c LP |
3151 | int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE); |
3152 | ||
22e268eb RR |
3153 | /* |
3154 | * ndiswrapper is under GPL by itself, but loads proprietary modules. | |
3155 | * Don't use add_taint_module(), as it would prevent ndiswrapper from | |
3156 | * using GPL-only symbols it needs. | |
3157 | */ | |
3158 | if (strcmp(mod->name, "ndiswrapper") == 0) | |
373d4d09 | 3159 | add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE); |
22e268eb RR |
3160 | |
3161 | /* driverloader was caught wrongly pretending to be under GPL */ | |
3162 | if (strcmp(mod->name, "driverloader") == 0) | |
373d4d09 RR |
3163 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
3164 | LOCKDEP_NOW_UNRELIABLE); | |
22e268eb | 3165 | |
c99af375 MG |
3166 | /* lve claims to be GPL but upstream won't provide source */ |
3167 | if (strcmp(mod->name, "lve") == 0) | |
373d4d09 RR |
3168 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE, |
3169 | LOCKDEP_NOW_UNRELIABLE); | |
c99af375 | 3170 | |
3205c36c LP |
3171 | if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE)) |
3172 | pr_warn("%s: module license taints kernel.\n", mod->name); | |
3173 | ||
22e268eb RR |
3174 | #ifdef CONFIG_MODVERSIONS |
3175 | if ((mod->num_syms && !mod->crcs) | |
3176 | || (mod->num_gpl_syms && !mod->gpl_crcs) | |
3177 | || (mod->num_gpl_future_syms && !mod->gpl_future_crcs) | |
3178 | #ifdef CONFIG_UNUSED_SYMBOLS | |
3179 | || (mod->num_unused_syms && !mod->unused_crcs) | |
3180 | || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs) | |
3181 | #endif | |
3182 | ) { | |
3183 | return try_to_force_load(mod, | |
3184 | "no versions for exported symbols"); | |
3185 | } | |
3186 | #endif | |
3187 | return 0; | |
3188 | } | |
3189 | ||
3190 | static void flush_module_icache(const struct module *mod) | |
3191 | { | |
3192 | mm_segment_t old_fs; | |
3193 | ||
3194 | /* flush the icache in correct context */ | |
3195 | old_fs = get_fs(); | |
3196 | set_fs(KERNEL_DS); | |
3197 | ||
3198 | /* | |
3199 | * Flush the instruction cache, since we've played with text. | |
3200 | * Do it before processing of module parameters, so the module | |
3201 | * can provide parameter accessor functions of its own. | |
3202 | */ | |
7523e4dc RR |
3203 | if (mod->init_layout.base) |
3204 | flush_icache_range((unsigned long)mod->init_layout.base, | |
3205 | (unsigned long)mod->init_layout.base | |
3206 | + mod->init_layout.size); | |
3207 | flush_icache_range((unsigned long)mod->core_layout.base, | |
3208 | (unsigned long)mod->core_layout.base + mod->core_layout.size); | |
22e268eb RR |
3209 | |
3210 | set_fs(old_fs); | |
3211 | } | |
3212 | ||
74e08fcf JB |
3213 | int __weak module_frob_arch_sections(Elf_Ehdr *hdr, |
3214 | Elf_Shdr *sechdrs, | |
3215 | char *secstrings, | |
3216 | struct module *mod) | |
3217 | { | |
3218 | return 0; | |
3219 | } | |
3220 | ||
be7de5f9 PB |
3221 | /* module_blacklist is a comma-separated list of module names */ |
3222 | static char *module_blacklist; | |
3223 | static bool blacklisted(char *module_name) | |
3224 | { | |
3225 | const char *p; | |
3226 | size_t len; | |
3227 | ||
3228 | if (!module_blacklist) | |
3229 | return false; | |
3230 | ||
3231 | for (p = module_blacklist; *p; p += len) { | |
3232 | len = strcspn(p, ","); | |
3233 | if (strlen(module_name) == len && !memcmp(module_name, p, len)) | |
3234 | return true; | |
3235 | if (p[len] == ',') | |
3236 | len++; | |
3237 | } | |
3238 | return false; | |
3239 | } | |
3240 | core_param(module_blacklist, module_blacklist, charp, 0400); | |
3241 | ||
2f3238ae | 3242 | static struct module *layout_and_allocate(struct load_info *info, int flags) |
1da177e4 | 3243 | { |
d913188c | 3244 | /* Module within temporary copy. */ |
1da177e4 | 3245 | struct module *mod; |
444d13ff | 3246 | unsigned int ndx; |
d913188c | 3247 | int err; |
3ae91c21 | 3248 | |
2f3238ae | 3249 | mod = setup_load_info(info, flags); |
d913188c RR |
3250 | if (IS_ERR(mod)) |
3251 | return mod; | |
1da177e4 | 3252 | |
be7de5f9 PB |
3253 | if (blacklisted(mod->name)) |
3254 | return ERR_PTR(-EPERM); | |
3255 | ||
2f3238ae | 3256 | err = check_modinfo(mod, info, flags); |
40dd2560 RR |
3257 | if (err) |
3258 | return ERR_PTR(err); | |
1da177e4 | 3259 | |
1da177e4 | 3260 | /* Allow arches to frob section contents and sizes. */ |
49668688 RR |
3261 | err = module_frob_arch_sections(info->hdr, info->sechdrs, |
3262 | info->secstrings, mod); | |
1da177e4 | 3263 | if (err < 0) |
8d8022e8 | 3264 | return ERR_PTR(err); |
1da177e4 | 3265 | |
8d8022e8 RR |
3266 | /* We will do a special allocation for per-cpu sections later. */ |
3267 | info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
1da177e4 | 3268 | |
444d13ff JY |
3269 | /* |
3270 | * Mark ro_after_init section with SHF_RO_AFTER_INIT so that | |
3271 | * layout_sections() can put it in the right place. | |
3272 | * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set. | |
3273 | */ | |
3274 | ndx = find_sec(info, ".data..ro_after_init"); | |
3275 | if (ndx) | |
3276 | info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT; | |
3277 | ||
1da177e4 LT |
3278 | /* Determine total sizes, and put offsets in sh_entsize. For now |
3279 | this is done generically; there doesn't appear to be any | |
3280 | special cases for the architectures. */ | |
49668688 | 3281 | layout_sections(mod, info); |
49668688 | 3282 | layout_symtab(mod, info); |
1da177e4 | 3283 | |
65b8a9b4 | 3284 | /* Allocate and move to the final place */ |
49668688 | 3285 | err = move_module(mod, info); |
d913188c | 3286 | if (err) |
8d8022e8 | 3287 | return ERR_PTR(err); |
d913188c RR |
3288 | |
3289 | /* Module has been copied to its final place now: return it. */ | |
3290 | mod = (void *)info->sechdrs[info->index.mod].sh_addr; | |
49668688 | 3291 | kmemleak_load_module(mod, info); |
d913188c | 3292 | return mod; |
d913188c RR |
3293 | } |
3294 | ||
3295 | /* mod is no longer valid after this! */ | |
3296 | static void module_deallocate(struct module *mod, struct load_info *info) | |
3297 | { | |
d913188c | 3298 | percpu_modfree(mod); |
d453cded | 3299 | module_arch_freeing_init(mod); |
7523e4dc RR |
3300 | module_memfree(mod->init_layout.base); |
3301 | module_memfree(mod->core_layout.base); | |
d913188c RR |
3302 | } |
3303 | ||
74e08fcf JB |
3304 | int __weak module_finalize(const Elf_Ehdr *hdr, |
3305 | const Elf_Shdr *sechdrs, | |
3306 | struct module *me) | |
3307 | { | |
3308 | return 0; | |
3309 | } | |
3310 | ||
811d66a0 RR |
3311 | static int post_relocation(struct module *mod, const struct load_info *info) |
3312 | { | |
51f3d0f4 | 3313 | /* Sort exception table now relocations are done. */ |
811d66a0 RR |
3314 | sort_extable(mod->extable, mod->extable + mod->num_exentries); |
3315 | ||
3316 | /* Copy relocated percpu area over. */ | |
3317 | percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr, | |
3318 | info->sechdrs[info->index.pcpu].sh_size); | |
3319 | ||
51f3d0f4 | 3320 | /* Setup kallsyms-specific fields. */ |
811d66a0 RR |
3321 | add_kallsyms(mod, info); |
3322 | ||
3323 | /* Arch-specific module finalizing. */ | |
3324 | return module_finalize(info->hdr, info->sechdrs, mod); | |
3325 | } | |
3326 | ||
9bb9c3be RR |
3327 | /* Is this module of this name done loading? No locks held. */ |
3328 | static bool finished_loading(const char *name) | |
3329 | { | |
3330 | struct module *mod; | |
3331 | bool ret; | |
3332 | ||
9cc019b8 PZ |
3333 | /* |
3334 | * The module_mutex should not be a heavily contended lock; | |
3335 | * if we get the occasional sleep here, we'll go an extra iteration | |
3336 | * in the wait_event_interruptible(), which is harmless. | |
3337 | */ | |
3338 | sched_annotate_sleep(); | |
9bb9c3be | 3339 | mutex_lock(&module_mutex); |
4f6de4d5 | 3340 | mod = find_module_all(name, strlen(name), true); |
0d21b0e3 RR |
3341 | ret = !mod || mod->state == MODULE_STATE_LIVE |
3342 | || mod->state == MODULE_STATE_GOING; | |
9bb9c3be RR |
3343 | mutex_unlock(&module_mutex); |
3344 | ||
3345 | return ret; | |
3346 | } | |
3347 | ||
34e1169d KC |
3348 | /* Call module constructors. */ |
3349 | static void do_mod_ctors(struct module *mod) | |
3350 | { | |
3351 | #ifdef CONFIG_CONSTRUCTORS | |
3352 | unsigned long i; | |
3353 | ||
3354 | for (i = 0; i < mod->num_ctors; i++) | |
3355 | mod->ctors[i](); | |
3356 | #endif | |
3357 | } | |
3358 | ||
c7496379 RR |
3359 | /* For freeing module_init on success, in case kallsyms traversing */ |
3360 | struct mod_initfree { | |
3361 | struct rcu_head rcu; | |
3362 | void *module_init; | |
3363 | }; | |
3364 | ||
3365 | static void do_free_init(struct rcu_head *head) | |
3366 | { | |
3367 | struct mod_initfree *m = container_of(head, struct mod_initfree, rcu); | |
3368 | module_memfree(m->module_init); | |
3369 | kfree(m); | |
3370 | } | |
3371 | ||
be02a186 JK |
3372 | /* |
3373 | * This is where the real work happens. | |
3374 | * | |
3375 | * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb | |
3376 | * helper command 'lx-symbols'. | |
3377 | */ | |
3378 | static noinline int do_init_module(struct module *mod) | |
34e1169d KC |
3379 | { |
3380 | int ret = 0; | |
c7496379 RR |
3381 | struct mod_initfree *freeinit; |
3382 | ||
3383 | freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL); | |
3384 | if (!freeinit) { | |
3385 | ret = -ENOMEM; | |
3386 | goto fail; | |
3387 | } | |
7523e4dc | 3388 | freeinit->module_init = mod->init_layout.base; |
34e1169d | 3389 | |
774a1221 TH |
3390 | /* |
3391 | * We want to find out whether @mod uses async during init. Clear | |
3392 | * PF_USED_ASYNC. async_schedule*() will set it. | |
3393 | */ | |
3394 | current->flags &= ~PF_USED_ASYNC; | |
3395 | ||
34e1169d KC |
3396 | do_mod_ctors(mod); |
3397 | /* Start the module */ | |
3398 | if (mod->init != NULL) | |
3399 | ret = do_one_initcall(mod->init); | |
3400 | if (ret < 0) { | |
c7496379 | 3401 | goto fail_free_freeinit; |
34e1169d KC |
3402 | } |
3403 | if (ret > 0) { | |
bddb12b3 AM |
3404 | pr_warn("%s: '%s'->init suspiciously returned %d, it should " |
3405 | "follow 0/-E convention\n" | |
3406 | "%s: loading module anyway...\n", | |
3407 | __func__, mod->name, ret, __func__); | |
34e1169d KC |
3408 | dump_stack(); |
3409 | } | |
3410 | ||
3411 | /* Now it's a first class citizen! */ | |
3412 | mod->state = MODULE_STATE_LIVE; | |
3413 | blocking_notifier_call_chain(&module_notify_list, | |
3414 | MODULE_STATE_LIVE, mod); | |
3415 | ||
774a1221 TH |
3416 | /* |
3417 | * We need to finish all async code before the module init sequence | |
3418 | * is done. This has potential to deadlock. For example, a newly | |
3419 | * detected block device can trigger request_module() of the | |
3420 | * default iosched from async probing task. Once userland helper | |
3421 | * reaches here, async_synchronize_full() will wait on the async | |
3422 | * task waiting on request_module() and deadlock. | |
3423 | * | |
3424 | * This deadlock is avoided by perfomring async_synchronize_full() | |
3425 | * iff module init queued any async jobs. This isn't a full | |
3426 | * solution as it will deadlock the same if module loading from | |
3427 | * async jobs nests more than once; however, due to the various | |
3428 | * constraints, this hack seems to be the best option for now. | |
3429 | * Please refer to the following thread for details. | |
3430 | * | |
3431 | * http://thread.gmane.org/gmane.linux.kernel/1420814 | |
3432 | */ | |
f2411da7 | 3433 | if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC)) |
774a1221 | 3434 | async_synchronize_full(); |
34e1169d KC |
3435 | |
3436 | mutex_lock(&module_mutex); | |
3437 | /* Drop initial reference. */ | |
3438 | module_put(mod); | |
3439 | trim_init_extable(mod); | |
3440 | #ifdef CONFIG_KALLSYMS | |
8244062e RR |
3441 | /* Switch to core kallsyms now init is done: kallsyms may be walking! */ |
3442 | rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms); | |
34e1169d | 3443 | #endif |
444d13ff | 3444 | module_enable_ro(mod, true); |
93c2e105 | 3445 | mod_tree_remove_init(mod); |
85c898db | 3446 | disable_ro_nx(&mod->init_layout); |
d453cded | 3447 | module_arch_freeing_init(mod); |
7523e4dc RR |
3448 | mod->init_layout.base = NULL; |
3449 | mod->init_layout.size = 0; | |
3450 | mod->init_layout.ro_size = 0; | |
444d13ff | 3451 | mod->init_layout.ro_after_init_size = 0; |
7523e4dc | 3452 | mod->init_layout.text_size = 0; |
c7496379 RR |
3453 | /* |
3454 | * We want to free module_init, but be aware that kallsyms may be | |
0be964be PZ |
3455 | * walking this with preempt disabled. In all the failure paths, we |
3456 | * call synchronize_sched(), but we don't want to slow down the success | |
3457 | * path, so use actual RCU here. | |
c7496379 | 3458 | */ |
0be964be | 3459 | call_rcu_sched(&freeinit->rcu, do_free_init); |
34e1169d KC |
3460 | mutex_unlock(&module_mutex); |
3461 | wake_up_all(&module_wq); | |
3462 | ||
3463 | return 0; | |
c7496379 RR |
3464 | |
3465 | fail_free_freeinit: | |
3466 | kfree(freeinit); | |
3467 | fail: | |
3468 | /* Try to protect us from buggy refcounters. */ | |
3469 | mod->state = MODULE_STATE_GOING; | |
3470 | synchronize_sched(); | |
3471 | module_put(mod); | |
3472 | blocking_notifier_call_chain(&module_notify_list, | |
3473 | MODULE_STATE_GOING, mod); | |
7e545d6e | 3474 | klp_module_going(mod); |
7dcd182b | 3475 | ftrace_release_mod(mod); |
c7496379 RR |
3476 | free_module(mod); |
3477 | wake_up_all(&module_wq); | |
3478 | return ret; | |
34e1169d KC |
3479 | } |
3480 | ||
3481 | static int may_init_module(void) | |
3482 | { | |
3483 | if (!capable(CAP_SYS_MODULE) || modules_disabled) | |
3484 | return -EPERM; | |
3485 | ||
3486 | return 0; | |
3487 | } | |
3488 | ||
a3535c7e RR |
3489 | /* |
3490 | * We try to place it in the list now to make sure it's unique before | |
3491 | * we dedicate too many resources. In particular, temporary percpu | |
3492 | * memory exhaustion. | |
3493 | */ | |
3494 | static int add_unformed_module(struct module *mod) | |
3495 | { | |
3496 | int err; | |
3497 | struct module *old; | |
3498 | ||
3499 | mod->state = MODULE_STATE_UNFORMED; | |
3500 | ||
3501 | again: | |
3502 | mutex_lock(&module_mutex); | |
4f6de4d5 MK |
3503 | old = find_module_all(mod->name, strlen(mod->name), true); |
3504 | if (old != NULL) { | |
a3535c7e RR |
3505 | if (old->state == MODULE_STATE_COMING |
3506 | || old->state == MODULE_STATE_UNFORMED) { | |
3507 | /* Wait in case it fails to load. */ | |
3508 | mutex_unlock(&module_mutex); | |
9cc019b8 PZ |
3509 | err = wait_event_interruptible(module_wq, |
3510 | finished_loading(mod->name)); | |
a3535c7e RR |
3511 | if (err) |
3512 | goto out_unlocked; | |
3513 | goto again; | |
3514 | } | |
3515 | err = -EEXIST; | |
3516 | goto out; | |
3517 | } | |
4f666546 | 3518 | mod_update_bounds(mod); |
a3535c7e | 3519 | list_add_rcu(&mod->list, &modules); |
93c2e105 | 3520 | mod_tree_insert(mod); |
a3535c7e RR |
3521 | err = 0; |
3522 | ||
3523 | out: | |
3524 | mutex_unlock(&module_mutex); | |
3525 | out_unlocked: | |
3526 | return err; | |
3527 | } | |
3528 | ||
3529 | static int complete_formation(struct module *mod, struct load_info *info) | |
3530 | { | |
3531 | int err; | |
3532 | ||
3533 | mutex_lock(&module_mutex); | |
3534 | ||
3535 | /* Find duplicate symbols (must be called under lock). */ | |
3536 | err = verify_export_symbols(mod); | |
3537 | if (err < 0) | |
3538 | goto out; | |
3539 | ||
3540 | /* This relies on module_mutex for list integrity. */ | |
3541 | module_bug_finalize(info->hdr, info->sechdrs, mod); | |
3542 | ||
444d13ff | 3543 | module_enable_ro(mod, false); |
85c898db | 3544 | module_enable_nx(mod); |
4982223e | 3545 | |
a3535c7e RR |
3546 | /* Mark state as coming so strong_try_module_get() ignores us, |
3547 | * but kallsyms etc. can see us. */ | |
3548 | mod->state = MODULE_STATE_COMING; | |
4982223e RR |
3549 | mutex_unlock(&module_mutex); |
3550 | ||
4982223e | 3551 | return 0; |
a3535c7e RR |
3552 | |
3553 | out: | |
3554 | mutex_unlock(&module_mutex); | |
3555 | return err; | |
3556 | } | |
3557 | ||
4c973d16 JY |
3558 | static int prepare_coming_module(struct module *mod) |
3559 | { | |
7e545d6e JY |
3560 | int err; |
3561 | ||
4c973d16 | 3562 | ftrace_module_enable(mod); |
7e545d6e JY |
3563 | err = klp_module_coming(mod); |
3564 | if (err) | |
3565 | return err; | |
3566 | ||
4c973d16 JY |
3567 | blocking_notifier_call_chain(&module_notify_list, |
3568 | MODULE_STATE_COMING, mod); | |
3569 | return 0; | |
3570 | } | |
3571 | ||
ecc86170 LR |
3572 | static int unknown_module_param_cb(char *param, char *val, const char *modname, |
3573 | void *arg) | |
54041d8a | 3574 | { |
f2411da7 LR |
3575 | struct module *mod = arg; |
3576 | int ret; | |
3577 | ||
3578 | if (strcmp(param, "async_probe") == 0) { | |
3579 | mod->async_probe_requested = true; | |
3580 | return 0; | |
3581 | } | |
3582 | ||
6da0b565 | 3583 | /* Check for magic 'dyndbg' arg */ |
f2411da7 | 3584 | ret = ddebug_dyndbg_module_param_cb(param, val, modname); |
bddb12b3 AM |
3585 | if (ret != 0) |
3586 | pr_warn("%s: unknown parameter '%s' ignored\n", modname, param); | |
54041d8a RR |
3587 | return 0; |
3588 | } | |
3589 | ||
d913188c RR |
3590 | /* Allocate and load the module: note that size of section 0 is always |
3591 | zero, and we rely on this for optional sections. */ | |
2f3238ae RR |
3592 | static int load_module(struct load_info *info, const char __user *uargs, |
3593 | int flags) | |
d913188c | 3594 | { |
a3535c7e | 3595 | struct module *mod; |
d913188c | 3596 | long err; |
51e158c1 | 3597 | char *after_dashes; |
d913188c | 3598 | |
bca014ca | 3599 | err = module_sig_check(info, flags); |
34e1169d KC |
3600 | if (err) |
3601 | goto free_copy; | |
d913188c | 3602 | |
34e1169d | 3603 | err = elf_header_check(info); |
d913188c | 3604 | if (err) |
34e1169d | 3605 | goto free_copy; |
d913188c RR |
3606 | |
3607 | /* Figure out module layout, and allocate all the memory. */ | |
2f3238ae | 3608 | mod = layout_and_allocate(info, flags); |
65b8a9b4 LT |
3609 | if (IS_ERR(mod)) { |
3610 | err = PTR_ERR(mod); | |
d913188c | 3611 | goto free_copy; |
1da177e4 | 3612 | } |
1da177e4 | 3613 | |
a3535c7e RR |
3614 | /* Reserve our place in the list. */ |
3615 | err = add_unformed_module(mod); | |
3616 | if (err) | |
1fb9341a | 3617 | goto free_module; |
1fb9341a | 3618 | |
106a4ee2 | 3619 | #ifdef CONFIG_MODULE_SIG |
34e1169d | 3620 | mod->sig_ok = info->sig_ok; |
64748a2c | 3621 | if (!mod->sig_ok) { |
bddb12b3 | 3622 | pr_notice_once("%s: module verification failed: signature " |
ab92ebbb | 3623 | "and/or required key missing - tainting " |
bddb12b3 | 3624 | "kernel\n", mod->name); |
66cc69e3 | 3625 | add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK); |
64748a2c | 3626 | } |
106a4ee2 RR |
3627 | #endif |
3628 | ||
8d8022e8 | 3629 | /* To avoid stressing percpu allocator, do this once we're unique. */ |
9eb76d77 | 3630 | err = percpu_modalloc(mod, info); |
8d8022e8 RR |
3631 | if (err) |
3632 | goto unlink_mod; | |
3633 | ||
49668688 | 3634 | /* Now module is in final location, initialize linked lists, etc. */ |
9f85a4bb RR |
3635 | err = module_unload_init(mod); |
3636 | if (err) | |
1fb9341a | 3637 | goto unlink_mod; |
1da177e4 | 3638 | |
cf2fde7b | 3639 | init_param_lock(mod); |
b51d23e4 | 3640 | |
22e268eb RR |
3641 | /* Now we've got everything in the final locations, we can |
3642 | * find optional sections. */ | |
eb3057df FH |
3643 | err = find_module_sections(mod, info); |
3644 | if (err) | |
3645 | goto free_unload; | |
9b37ccfc | 3646 | |
49668688 | 3647 | err = check_module_license_and_versions(mod); |
22e268eb RR |
3648 | if (err) |
3649 | goto free_unload; | |
9841d61d | 3650 | |
c988d2b2 | 3651 | /* Set up MODINFO_ATTR fields */ |
34e1169d | 3652 | setup_modinfo(mod, info); |
c988d2b2 | 3653 | |
1da177e4 | 3654 | /* Fix up syms, so that st_value is a pointer to location. */ |
34e1169d | 3655 | err = simplify_symbols(mod, info); |
1da177e4 | 3656 | if (err < 0) |
d913188c | 3657 | goto free_modinfo; |
1da177e4 | 3658 | |
34e1169d | 3659 | err = apply_relocations(mod, info); |
22e268eb | 3660 | if (err < 0) |
d913188c | 3661 | goto free_modinfo; |
1da177e4 | 3662 | |
34e1169d | 3663 | err = post_relocation(mod, info); |
1da177e4 | 3664 | if (err < 0) |
d913188c | 3665 | goto free_modinfo; |
1da177e4 | 3666 | |
22e268eb | 3667 | flush_module_icache(mod); |
378bac82 | 3668 | |
6526c534 RR |
3669 | /* Now copy in args */ |
3670 | mod->args = strndup_user(uargs, ~0UL >> 1); | |
3671 | if (IS_ERR(mod->args)) { | |
3672 | err = PTR_ERR(mod->args); | |
3673 | goto free_arch_cleanup; | |
3674 | } | |
8d3b33f6 | 3675 | |
34e1169d | 3676 | dynamic_debug_setup(info->debug, info->num_debug); |
ff49d74a | 3677 | |
a949ae56 SRRH |
3678 | /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */ |
3679 | ftrace_module_init(mod); | |
3680 | ||
a3535c7e RR |
3681 | /* Finally it's fully formed, ready to start executing. */ |
3682 | err = complete_formation(mod, info); | |
3683 | if (err) | |
1fb9341a | 3684 | goto ddebug_cleanup; |
be593f4c | 3685 | |
4c973d16 JY |
3686 | err = prepare_coming_module(mod); |
3687 | if (err) | |
3688 | goto bug_cleanup; | |
3689 | ||
51f3d0f4 | 3690 | /* Module is ready to execute: parsing args may do that. */ |
51e158c1 | 3691 | after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, |
4355efbd | 3692 | -32768, 32767, mod, |
ecc86170 | 3693 | unknown_module_param_cb); |
51e158c1 RR |
3694 | if (IS_ERR(after_dashes)) { |
3695 | err = PTR_ERR(after_dashes); | |
4c973d16 | 3696 | goto coming_cleanup; |
51e158c1 RR |
3697 | } else if (after_dashes) { |
3698 | pr_warn("%s: parameters '%s' after `--' ignored\n", | |
3699 | mod->name, after_dashes); | |
3700 | } | |
1da177e4 | 3701 | |
51f3d0f4 | 3702 | /* Link in to syfs. */ |
34e1169d | 3703 | err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp); |
1da177e4 | 3704 | if (err < 0) |
4c973d16 | 3705 | goto coming_cleanup; |
80a3d1bb | 3706 | |
1ce15ef4 JY |
3707 | if (is_livepatch_module(mod)) { |
3708 | err = copy_module_elf(mod, info); | |
3709 | if (err < 0) | |
3710 | goto sysfs_cleanup; | |
3711 | } | |
3712 | ||
48fd1188 | 3713 | /* Get rid of temporary copy. */ |
34e1169d | 3714 | free_copy(info); |
1da177e4 LT |
3715 | |
3716 | /* Done! */ | |
51f3d0f4 | 3717 | trace_module_load(mod); |
34e1169d KC |
3718 | |
3719 | return do_init_module(mod); | |
1da177e4 | 3720 | |
1ce15ef4 JY |
3721 | sysfs_cleanup: |
3722 | mod_sysfs_teardown(mod); | |
4c973d16 | 3723 | coming_cleanup: |
885a78d4 | 3724 | mod->state = MODULE_STATE_GOING; |
4c973d16 JY |
3725 | blocking_notifier_call_chain(&module_notify_list, |
3726 | MODULE_STATE_GOING, mod); | |
7e545d6e | 3727 | klp_module_going(mod); |
1fb9341a RR |
3728 | bug_cleanup: |
3729 | /* module_bug_cleanup needs module_mutex protection */ | |
75676500 | 3730 | mutex_lock(&module_mutex); |
5336377d | 3731 | module_bug_cleanup(mod); |
ee61abb3 | 3732 | mutex_unlock(&module_mutex); |
ff7e0055 AL |
3733 | |
3734 | /* we can't deallocate the module until we clear memory protection */ | |
85c898db RR |
3735 | module_disable_ro(mod); |
3736 | module_disable_nx(mod); | |
ff7e0055 | 3737 | |
a3535c7e | 3738 | ddebug_cleanup: |
1fb9341a | 3739 | dynamic_debug_remove(info->debug); |
e91defa2 | 3740 | synchronize_sched(); |
6526c534 RR |
3741 | kfree(mod->args); |
3742 | free_arch_cleanup: | |
1da177e4 | 3743 | module_arch_cleanup(mod); |
d913188c | 3744 | free_modinfo: |
a263f776 | 3745 | free_modinfo(mod); |
22e268eb | 3746 | free_unload: |
1da177e4 | 3747 | module_unload_free(mod); |
1fb9341a RR |
3748 | unlink_mod: |
3749 | mutex_lock(&module_mutex); | |
3750 | /* Unlink carefully: kallsyms could be walking list. */ | |
3751 | list_del_rcu(&mod->list); | |
758556bd | 3752 | mod_tree_remove(mod); |
1fb9341a | 3753 | wake_up_all(&module_wq); |
0be964be PZ |
3754 | /* Wait for RCU-sched synchronizing before releasing mod->list. */ |
3755 | synchronize_sched(); | |
1fb9341a | 3756 | mutex_unlock(&module_mutex); |
d913188c | 3757 | free_module: |
049fb9bd SRRH |
3758 | /* |
3759 | * Ftrace needs to clean up what it initialized. | |
3760 | * This does nothing if ftrace_module_init() wasn't called, | |
3761 | * but it must be called outside of module_mutex. | |
3762 | */ | |
3763 | ftrace_release_mod(mod); | |
35a9393c | 3764 | /* Free lock-classes; relies on the preceding sync_rcu() */ |
7523e4dc | 3765 | lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size); |
35a9393c | 3766 | |
34e1169d | 3767 | module_deallocate(mod, info); |
d913188c | 3768 | free_copy: |
34e1169d KC |
3769 | free_copy(info); |
3770 | return err; | |
b99b87f7 PO |
3771 | } |
3772 | ||
17da2bd9 HC |
3773 | SYSCALL_DEFINE3(init_module, void __user *, umod, |
3774 | unsigned long, len, const char __user *, uargs) | |
1da177e4 | 3775 | { |
34e1169d KC |
3776 | int err; |
3777 | struct load_info info = { }; | |
1da177e4 | 3778 | |
34e1169d KC |
3779 | err = may_init_module(); |
3780 | if (err) | |
3781 | return err; | |
1da177e4 | 3782 | |
34e1169d KC |
3783 | pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n", |
3784 | umod, len, uargs); | |
1da177e4 | 3785 | |
34e1169d KC |
3786 | err = copy_module_from_user(umod, len, &info); |
3787 | if (err) | |
3788 | return err; | |
1da177e4 | 3789 | |
2f3238ae | 3790 | return load_module(&info, uargs, 0); |
34e1169d | 3791 | } |
94462ad3 | 3792 | |
2f3238ae | 3793 | SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) |
34e1169d | 3794 | { |
34e1169d | 3795 | struct load_info info = { }; |
a1db7420 MZ |
3796 | loff_t size; |
3797 | void *hdr; | |
3798 | int err; | |
94462ad3 | 3799 | |
34e1169d KC |
3800 | err = may_init_module(); |
3801 | if (err) | |
3802 | return err; | |
1da177e4 | 3803 | |
2f3238ae | 3804 | pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags); |
6c5db22d | 3805 | |
2f3238ae RR |
3806 | if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS |
3807 | |MODULE_INIT_IGNORE_VERMAGIC)) | |
3808 | return -EINVAL; | |
d6de2c80 | 3809 | |
a1db7420 MZ |
3810 | err = kernel_read_file_from_fd(fd, &hdr, &size, INT_MAX, |
3811 | READING_MODULE); | |
34e1169d KC |
3812 | if (err) |
3813 | return err; | |
a1db7420 MZ |
3814 | info.hdr = hdr; |
3815 | info.len = size; | |
1da177e4 | 3816 | |
2f3238ae | 3817 | return load_module(&info, uargs, flags); |
1da177e4 LT |
3818 | } |
3819 | ||
3820 | static inline int within(unsigned long addr, void *start, unsigned long size) | |
3821 | { | |
3822 | return ((void *)addr >= start && (void *)addr < start + size); | |
3823 | } | |
3824 | ||
3825 | #ifdef CONFIG_KALLSYMS | |
3826 | /* | |
3827 | * This ignores the intensely annoying "mapping symbols" found | |
3828 | * in ARM ELF files: $a, $t and $d. | |
3829 | */ | |
3830 | static inline int is_arm_mapping_symbol(const char *str) | |
3831 | { | |
2e3a10a1 RK |
3832 | if (str[0] == '.' && str[1] == 'L') |
3833 | return true; | |
6c34f1f5 | 3834 | return str[0] == '$' && strchr("axtd", str[1]) |
1da177e4 LT |
3835 | && (str[2] == '\0' || str[2] == '.'); |
3836 | } | |
3837 | ||
8244062e | 3838 | static const char *symname(struct mod_kallsyms *kallsyms, unsigned int symnum) |
2e7bac53 | 3839 | { |
8244062e | 3840 | return kallsyms->strtab + kallsyms->symtab[symnum].st_name; |
2e7bac53 RR |
3841 | } |
3842 | ||
1da177e4 LT |
3843 | static const char *get_ksymbol(struct module *mod, |
3844 | unsigned long addr, | |
3845 | unsigned long *size, | |
3846 | unsigned long *offset) | |
3847 | { | |
3848 | unsigned int i, best = 0; | |
3849 | unsigned long nextval; | |
8244062e | 3850 | struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); |
1da177e4 LT |
3851 | |
3852 | /* At worse, next value is at end of module */ | |
a06f6211 | 3853 | if (within_module_init(addr, mod)) |
7523e4dc | 3854 | nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size; |
22a8bdeb | 3855 | else |
7523e4dc | 3856 | nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size; |
1da177e4 | 3857 | |
25985edc | 3858 | /* Scan for closest preceding symbol, and next symbol. (ELF |
22a8bdeb | 3859 | starts real symbols at 1). */ |
8244062e RR |
3860 | for (i = 1; i < kallsyms->num_symtab; i++) { |
3861 | if (kallsyms->symtab[i].st_shndx == SHN_UNDEF) | |
1da177e4 LT |
3862 | continue; |
3863 | ||
3864 | /* We ignore unnamed symbols: they're uninformative | |
3865 | * and inserted at a whim. */ | |
8244062e RR |
3866 | if (*symname(kallsyms, i) == '\0' |
3867 | || is_arm_mapping_symbol(symname(kallsyms, i))) | |
2e7bac53 RR |
3868 | continue; |
3869 | ||
8244062e RR |
3870 | if (kallsyms->symtab[i].st_value <= addr |
3871 | && kallsyms->symtab[i].st_value > kallsyms->symtab[best].st_value) | |
1da177e4 | 3872 | best = i; |
8244062e RR |
3873 | if (kallsyms->symtab[i].st_value > addr |
3874 | && kallsyms->symtab[i].st_value < nextval) | |
3875 | nextval = kallsyms->symtab[i].st_value; | |
1da177e4 LT |
3876 | } |
3877 | ||
3878 | if (!best) | |
3879 | return NULL; | |
3880 | ||
ffb45122 | 3881 | if (size) |
8244062e | 3882 | *size = nextval - kallsyms->symtab[best].st_value; |
ffb45122 | 3883 | if (offset) |
8244062e RR |
3884 | *offset = addr - kallsyms->symtab[best].st_value; |
3885 | return symname(kallsyms, best); | |
1da177e4 LT |
3886 | } |
3887 | ||
6dd06c9f RR |
3888 | /* For kallsyms to ask for address resolution. NULL means not found. Careful |
3889 | * not to lock to avoid deadlock on oopses, simply disable preemption. */ | |
92dfc9dc | 3890 | const char *module_address_lookup(unsigned long addr, |
6dd06c9f RR |
3891 | unsigned long *size, |
3892 | unsigned long *offset, | |
3893 | char **modname, | |
3894 | char *namebuf) | |
1da177e4 | 3895 | { |
cb2a5205 | 3896 | const char *ret = NULL; |
b7df4d1b | 3897 | struct module *mod; |
1da177e4 | 3898 | |
cb2a5205 | 3899 | preempt_disable(); |
b7df4d1b PZ |
3900 | mod = __module_address(addr); |
3901 | if (mod) { | |
3902 | if (modname) | |
3903 | *modname = mod->name; | |
3904 | ret = get_ksymbol(mod, addr, size, offset); | |
1da177e4 | 3905 | } |
6dd06c9f RR |
3906 | /* Make a copy in here where it's safe */ |
3907 | if (ret) { | |
3908 | strncpy(namebuf, ret, KSYM_NAME_LEN - 1); | |
3909 | ret = namebuf; | |
3910 | } | |
cb2a5205 | 3911 | preempt_enable(); |
b7df4d1b | 3912 | |
92dfc9dc | 3913 | return ret; |
1da177e4 LT |
3914 | } |
3915 | ||
9d65cb4a AD |
3916 | int lookup_module_symbol_name(unsigned long addr, char *symname) |
3917 | { | |
3918 | struct module *mod; | |
3919 | ||
cb2a5205 | 3920 | preempt_disable(); |
d72b3751 | 3921 | list_for_each_entry_rcu(mod, &modules, list) { |
0d21b0e3 RR |
3922 | if (mod->state == MODULE_STATE_UNFORMED) |
3923 | continue; | |
9b20a352 | 3924 | if (within_module(addr, mod)) { |
9d65cb4a AD |
3925 | const char *sym; |
3926 | ||
3927 | sym = get_ksymbol(mod, addr, NULL, NULL); | |
3928 | if (!sym) | |
3929 | goto out; | |
9281acea | 3930 | strlcpy(symname, sym, KSYM_NAME_LEN); |
cb2a5205 | 3931 | preempt_enable(); |
9d65cb4a AD |
3932 | return 0; |
3933 | } | |
3934 | } | |
3935 | out: | |
cb2a5205 | 3936 | preempt_enable(); |
9d65cb4a AD |
3937 | return -ERANGE; |
3938 | } | |
3939 | ||
a5c43dae AD |
3940 | int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, |
3941 | unsigned long *offset, char *modname, char *name) | |
3942 | { | |
3943 | struct module *mod; | |
3944 | ||
cb2a5205 | 3945 | preempt_disable(); |
d72b3751 | 3946 | list_for_each_entry_rcu(mod, &modules, list) { |
0d21b0e3 RR |
3947 | if (mod->state == MODULE_STATE_UNFORMED) |
3948 | continue; | |
9b20a352 | 3949 | if (within_module(addr, mod)) { |
a5c43dae AD |
3950 | const char *sym; |
3951 | ||
3952 | sym = get_ksymbol(mod, addr, size, offset); | |
3953 | if (!sym) | |
3954 | goto out; | |
3955 | if (modname) | |
9281acea | 3956 | strlcpy(modname, mod->name, MODULE_NAME_LEN); |
a5c43dae | 3957 | if (name) |
9281acea | 3958 | strlcpy(name, sym, KSYM_NAME_LEN); |
cb2a5205 | 3959 | preempt_enable(); |
a5c43dae AD |
3960 | return 0; |
3961 | } | |
3962 | } | |
3963 | out: | |
cb2a5205 | 3964 | preempt_enable(); |
a5c43dae AD |
3965 | return -ERANGE; |
3966 | } | |
3967 | ||
ea07890a AD |
3968 | int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, |
3969 | char *name, char *module_name, int *exported) | |
1da177e4 LT |
3970 | { |
3971 | struct module *mod; | |
3972 | ||
cb2a5205 | 3973 | preempt_disable(); |
d72b3751 | 3974 | list_for_each_entry_rcu(mod, &modules, list) { |
8244062e RR |
3975 | struct mod_kallsyms *kallsyms; |
3976 | ||
0d21b0e3 RR |
3977 | if (mod->state == MODULE_STATE_UNFORMED) |
3978 | continue; | |
8244062e RR |
3979 | kallsyms = rcu_dereference_sched(mod->kallsyms); |
3980 | if (symnum < kallsyms->num_symtab) { | |
3981 | *value = kallsyms->symtab[symnum].st_value; | |
3982 | *type = kallsyms->symtab[symnum].st_info; | |
3983 | strlcpy(name, symname(kallsyms, symnum), KSYM_NAME_LEN); | |
9281acea | 3984 | strlcpy(module_name, mod->name, MODULE_NAME_LEN); |
ca4787b7 | 3985 | *exported = is_exported(name, *value, mod); |
cb2a5205 | 3986 | preempt_enable(); |
ea07890a | 3987 | return 0; |
1da177e4 | 3988 | } |
8244062e | 3989 | symnum -= kallsyms->num_symtab; |
1da177e4 | 3990 | } |
cb2a5205 | 3991 | preempt_enable(); |
ea07890a | 3992 | return -ERANGE; |
1da177e4 LT |
3993 | } |
3994 | ||
3995 | static unsigned long mod_find_symname(struct module *mod, const char *name) | |
3996 | { | |
3997 | unsigned int i; | |
8244062e | 3998 | struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms); |
1da177e4 | 3999 | |
8244062e RR |
4000 | for (i = 0; i < kallsyms->num_symtab; i++) |
4001 | if (strcmp(name, symname(kallsyms, i)) == 0 && | |
4002 | kallsyms->symtab[i].st_info != 'U') | |
4003 | return kallsyms->symtab[i].st_value; | |
1da177e4 LT |
4004 | return 0; |
4005 | } | |
4006 | ||
4007 | /* Look for this name: can be of form module:name. */ | |
4008 | unsigned long module_kallsyms_lookup_name(const char *name) | |
4009 | { | |
4010 | struct module *mod; | |
4011 | char *colon; | |
4012 | unsigned long ret = 0; | |
4013 | ||
4014 | /* Don't lock: we're in enough trouble already. */ | |
cb2a5205 | 4015 | preempt_disable(); |
1da177e4 | 4016 | if ((colon = strchr(name, ':')) != NULL) { |
4f6de4d5 | 4017 | if ((mod = find_module_all(name, colon - name, false)) != NULL) |
1da177e4 | 4018 | ret = mod_find_symname(mod, colon+1); |
1da177e4 | 4019 | } else { |
0d21b0e3 RR |
4020 | list_for_each_entry_rcu(mod, &modules, list) { |
4021 | if (mod->state == MODULE_STATE_UNFORMED) | |
4022 | continue; | |
1da177e4 LT |
4023 | if ((ret = mod_find_symname(mod, name)) != 0) |
4024 | break; | |
0d21b0e3 | 4025 | } |
1da177e4 | 4026 | } |
cb2a5205 | 4027 | preempt_enable(); |
1da177e4 LT |
4028 | return ret; |
4029 | } | |
75a66614 AK |
4030 | |
4031 | int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, | |
4032 | struct module *, unsigned long), | |
4033 | void *data) | |
4034 | { | |
4035 | struct module *mod; | |
4036 | unsigned int i; | |
4037 | int ret; | |
4038 | ||
0be964be PZ |
4039 | module_assert_mutex(); |
4040 | ||
75a66614 | 4041 | list_for_each_entry(mod, &modules, list) { |
8244062e RR |
4042 | /* We hold module_mutex: no need for rcu_dereference_sched */ |
4043 | struct mod_kallsyms *kallsyms = mod->kallsyms; | |
4044 | ||
0d21b0e3 RR |
4045 | if (mod->state == MODULE_STATE_UNFORMED) |
4046 | continue; | |
8244062e RR |
4047 | for (i = 0; i < kallsyms->num_symtab; i++) { |
4048 | ret = fn(data, symname(kallsyms, i), | |
4049 | mod, kallsyms->symtab[i].st_value); | |
75a66614 AK |
4050 | if (ret != 0) |
4051 | return ret; | |
4052 | } | |
4053 | } | |
4054 | return 0; | |
4055 | } | |
1da177e4 LT |
4056 | #endif /* CONFIG_KALLSYMS */ |
4057 | ||
7fd8329b PM |
4058 | /* Maximum number of characters written by module_flags() */ |
4059 | #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) | |
4060 | ||
4061 | /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */ | |
21aa9280 | 4062 | static char *module_flags(struct module *mod, char *buf) |
fa3ba2e8 FM |
4063 | { |
4064 | int bx = 0; | |
4065 | ||
0d21b0e3 | 4066 | BUG_ON(mod->state == MODULE_STATE_UNFORMED); |
21aa9280 AV |
4067 | if (mod->taints || |
4068 | mod->state == MODULE_STATE_GOING || | |
4069 | mod->state == MODULE_STATE_COMING) { | |
fa3ba2e8 | 4070 | buf[bx++] = '('; |
cca3e707 | 4071 | bx += module_flags_taint(mod, buf + bx); |
21aa9280 AV |
4072 | /* Show a - for module-is-being-unloaded */ |
4073 | if (mod->state == MODULE_STATE_GOING) | |
4074 | buf[bx++] = '-'; | |
4075 | /* Show a + for module-is-being-loaded */ | |
4076 | if (mod->state == MODULE_STATE_COMING) | |
4077 | buf[bx++] = '+'; | |
fa3ba2e8 FM |
4078 | buf[bx++] = ')'; |
4079 | } | |
4080 | buf[bx] = '\0'; | |
4081 | ||
4082 | return buf; | |
4083 | } | |
4084 | ||
3b5d5c6b AD |
4085 | #ifdef CONFIG_PROC_FS |
4086 | /* Called by the /proc file system to return a list of modules. */ | |
4087 | static void *m_start(struct seq_file *m, loff_t *pos) | |
4088 | { | |
4089 | mutex_lock(&module_mutex); | |
4090 | return seq_list_start(&modules, *pos); | |
4091 | } | |
4092 | ||
4093 | static void *m_next(struct seq_file *m, void *p, loff_t *pos) | |
4094 | { | |
4095 | return seq_list_next(p, &modules, pos); | |
4096 | } | |
4097 | ||
4098 | static void m_stop(struct seq_file *m, void *p) | |
4099 | { | |
4100 | mutex_unlock(&module_mutex); | |
4101 | } | |
4102 | ||
1da177e4 LT |
4103 | static int m_show(struct seq_file *m, void *p) |
4104 | { | |
4105 | struct module *mod = list_entry(p, struct module, list); | |
7fd8329b | 4106 | char buf[MODULE_FLAGS_BUF_SIZE]; |
fa3ba2e8 | 4107 | |
0d21b0e3 RR |
4108 | /* We always ignore unformed modules. */ |
4109 | if (mod->state == MODULE_STATE_UNFORMED) | |
4110 | return 0; | |
4111 | ||
2f0f2a33 | 4112 | seq_printf(m, "%s %u", |
7523e4dc | 4113 | mod->name, mod->init_layout.size + mod->core_layout.size); |
1da177e4 LT |
4114 | print_unload_info(m, mod); |
4115 | ||
4116 | /* Informative for users. */ | |
4117 | seq_printf(m, " %s", | |
6da0b565 IA |
4118 | mod->state == MODULE_STATE_GOING ? "Unloading" : |
4119 | mod->state == MODULE_STATE_COMING ? "Loading" : | |
1da177e4 LT |
4120 | "Live"); |
4121 | /* Used by oprofile and other similar tools. */ | |
7523e4dc | 4122 | seq_printf(m, " 0x%pK", mod->core_layout.base); |
1da177e4 | 4123 | |
fa3ba2e8 FM |
4124 | /* Taints info */ |
4125 | if (mod->taints) | |
21aa9280 | 4126 | seq_printf(m, " %s", module_flags(mod, buf)); |
fa3ba2e8 | 4127 | |
6da0b565 | 4128 | seq_puts(m, "\n"); |
1da177e4 LT |
4129 | return 0; |
4130 | } | |
4131 | ||
4132 | /* Format: modulename size refcount deps address | |
4133 | ||
4134 | Where refcount is a number or -, and deps is a comma-separated list | |
4135 | of depends or -. | |
4136 | */ | |
3b5d5c6b | 4137 | static const struct seq_operations modules_op = { |
1da177e4 LT |
4138 | .start = m_start, |
4139 | .next = m_next, | |
4140 | .stop = m_stop, | |
4141 | .show = m_show | |
4142 | }; | |
4143 | ||
3b5d5c6b AD |
4144 | static int modules_open(struct inode *inode, struct file *file) |
4145 | { | |
4146 | return seq_open(file, &modules_op); | |
4147 | } | |
4148 | ||
4149 | static const struct file_operations proc_modules_operations = { | |
4150 | .open = modules_open, | |
4151 | .read = seq_read, | |
4152 | .llseek = seq_lseek, | |
4153 | .release = seq_release, | |
4154 | }; | |
4155 | ||
4156 | static int __init proc_modules_init(void) | |
4157 | { | |
4158 | proc_create("modules", 0, NULL, &proc_modules_operations); | |
4159 | return 0; | |
4160 | } | |
4161 | module_init(proc_modules_init); | |
4162 | #endif | |
4163 | ||
1da177e4 LT |
4164 | /* Given an address, look for it in the module exception tables. */ |
4165 | const struct exception_table_entry *search_module_extables(unsigned long addr) | |
4166 | { | |
1da177e4 LT |
4167 | const struct exception_table_entry *e = NULL; |
4168 | struct module *mod; | |
4169 | ||
24da1cbf | 4170 | preempt_disable(); |
d72b3751 | 4171 | list_for_each_entry_rcu(mod, &modules, list) { |
0d21b0e3 RR |
4172 | if (mod->state == MODULE_STATE_UNFORMED) |
4173 | continue; | |
1da177e4 LT |
4174 | if (mod->num_exentries == 0) |
4175 | continue; | |
22a8bdeb | 4176 | |
1da177e4 LT |
4177 | e = search_extable(mod->extable, |
4178 | mod->extable + mod->num_exentries - 1, | |
4179 | addr); | |
4180 | if (e) | |
4181 | break; | |
4182 | } | |
24da1cbf | 4183 | preempt_enable(); |
1da177e4 LT |
4184 | |
4185 | /* Now, if we found one, we are running inside it now, hence | |
22a8bdeb | 4186 | we cannot unload the module, hence no refcnt needed. */ |
1da177e4 LT |
4187 | return e; |
4188 | } | |
4189 | ||
4d435f9d | 4190 | /* |
e610499e RR |
4191 | * is_module_address - is this address inside a module? |
4192 | * @addr: the address to check. | |
4193 | * | |
4194 | * See is_module_text_address() if you simply want to see if the address | |
4195 | * is code (not data). | |
4d435f9d | 4196 | */ |
e610499e | 4197 | bool is_module_address(unsigned long addr) |
4d435f9d | 4198 | { |
e610499e | 4199 | bool ret; |
4d435f9d | 4200 | |
24da1cbf | 4201 | preempt_disable(); |
e610499e | 4202 | ret = __module_address(addr) != NULL; |
24da1cbf | 4203 | preempt_enable(); |
4d435f9d | 4204 | |
e610499e | 4205 | return ret; |
4d435f9d IM |
4206 | } |
4207 | ||
e610499e RR |
4208 | /* |
4209 | * __module_address - get the module which contains an address. | |
4210 | * @addr: the address. | |
4211 | * | |
4212 | * Must be called with preempt disabled or module mutex held so that | |
4213 | * module doesn't get freed during this. | |
4214 | */ | |
714f83d5 | 4215 | struct module *__module_address(unsigned long addr) |
1da177e4 LT |
4216 | { |
4217 | struct module *mod; | |
4218 | ||
3a642e99 RR |
4219 | if (addr < module_addr_min || addr > module_addr_max) |
4220 | return NULL; | |
4221 | ||
0be964be PZ |
4222 | module_assert_mutex_or_preempt(); |
4223 | ||
6c9692e2 | 4224 | mod = mod_find(addr); |
93c2e105 PZ |
4225 | if (mod) { |
4226 | BUG_ON(!within_module(addr, mod)); | |
0d21b0e3 | 4227 | if (mod->state == MODULE_STATE_UNFORMED) |
93c2e105 | 4228 | mod = NULL; |
0d21b0e3 | 4229 | } |
93c2e105 | 4230 | return mod; |
1da177e4 | 4231 | } |
c6b37801 | 4232 | EXPORT_SYMBOL_GPL(__module_address); |
1da177e4 | 4233 | |
e610499e RR |
4234 | /* |
4235 | * is_module_text_address - is this address inside module code? | |
4236 | * @addr: the address to check. | |
4237 | * | |
4238 | * See is_module_address() if you simply want to see if the address is | |
4239 | * anywhere in a module. See kernel_text_address() for testing if an | |
4240 | * address corresponds to kernel or module code. | |
4241 | */ | |
4242 | bool is_module_text_address(unsigned long addr) | |
4243 | { | |
4244 | bool ret; | |
4245 | ||
4246 | preempt_disable(); | |
4247 | ret = __module_text_address(addr) != NULL; | |
4248 | preempt_enable(); | |
4249 | ||
4250 | return ret; | |
4251 | } | |
4252 | ||
4253 | /* | |
4254 | * __module_text_address - get the module whose code contains an address. | |
4255 | * @addr: the address. | |
4256 | * | |
4257 | * Must be called with preempt disabled or module mutex held so that | |
4258 | * module doesn't get freed during this. | |
4259 | */ | |
4260 | struct module *__module_text_address(unsigned long addr) | |
4261 | { | |
4262 | struct module *mod = __module_address(addr); | |
4263 | if (mod) { | |
4264 | /* Make sure it's within the text section. */ | |
7523e4dc RR |
4265 | if (!within(addr, mod->init_layout.base, mod->init_layout.text_size) |
4266 | && !within(addr, mod->core_layout.base, mod->core_layout.text_size)) | |
e610499e RR |
4267 | mod = NULL; |
4268 | } | |
4269 | return mod; | |
4270 | } | |
c6b37801 | 4271 | EXPORT_SYMBOL_GPL(__module_text_address); |
e610499e | 4272 | |
1da177e4 LT |
4273 | /* Don't grab lock, we're oopsing. */ |
4274 | void print_modules(void) | |
4275 | { | |
4276 | struct module *mod; | |
7fd8329b | 4277 | char buf[MODULE_FLAGS_BUF_SIZE]; |
1da177e4 | 4278 | |
b231125a | 4279 | printk(KERN_DEFAULT "Modules linked in:"); |
d72b3751 AK |
4280 | /* Most callers should already have preempt disabled, but make sure */ |
4281 | preempt_disable(); | |
0d21b0e3 RR |
4282 | list_for_each_entry_rcu(mod, &modules, list) { |
4283 | if (mod->state == MODULE_STATE_UNFORMED) | |
4284 | continue; | |
27bba4d6 | 4285 | pr_cont(" %s%s", mod->name, module_flags(mod, buf)); |
0d21b0e3 | 4286 | } |
d72b3751 | 4287 | preempt_enable(); |
e14af7ee | 4288 | if (last_unloaded_module[0]) |
27bba4d6 JS |
4289 | pr_cont(" [last unloaded: %s]", last_unloaded_module); |
4290 | pr_cont("\n"); | |
1da177e4 LT |
4291 | } |
4292 | ||
1da177e4 | 4293 | #ifdef CONFIG_MODVERSIONS |
8c8ef42a RR |
4294 | /* Generate the signature for all relevant module structures here. |
4295 | * If these change, we don't want to try to parse the module. */ | |
4296 | void module_layout(struct module *mod, | |
4297 | struct modversion_info *ver, | |
4298 | struct kernel_param *kp, | |
4299 | struct kernel_symbol *ks, | |
65498646 | 4300 | struct tracepoint * const *tp) |
8c8ef42a RR |
4301 | { |
4302 | } | |
4303 | EXPORT_SYMBOL(module_layout); | |
1da177e4 | 4304 | #endif |