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1 | /* | |
2 | Copyright (C) 2002 Richard Henderson | |
3 | Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM. | |
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 | */ | |
19 | #include <linux/module.h> | |
20 | #include <linux/moduleloader.h> | |
21 | #include <linux/ftrace_event.h> | |
22 | #include <linux/init.h> | |
23 | #include <linux/kallsyms.h> | |
24 | #include <linux/fs.h> | |
25 | #include <linux/sysfs.h> | |
26 | #include <linux/kernel.h> | |
27 | #include <linux/slab.h> | |
28 | #include <linux/vmalloc.h> | |
29 | #include <linux/elf.h> | |
30 | #include <linux/proc_fs.h> | |
31 | #include <linux/seq_file.h> | |
32 | #include <linux/syscalls.h> | |
33 | #include <linux/fcntl.h> | |
34 | #include <linux/rcupdate.h> | |
35 | #include <linux/capability.h> | |
36 | #include <linux/cpu.h> | |
37 | #include <linux/moduleparam.h> | |
38 | #include <linux/errno.h> | |
39 | #include <linux/err.h> | |
40 | #include <linux/vermagic.h> | |
41 | #include <linux/notifier.h> | |
42 | #include <linux/sched.h> | |
43 | #include <linux/stop_machine.h> | |
44 | #include <linux/device.h> | |
45 | #include <linux/string.h> | |
46 | #include <linux/mutex.h> | |
47 | #include <linux/rculist.h> | |
48 | #include <asm/uaccess.h> | |
49 | #include <asm/cacheflush.h> | |
50 | #include <asm/mmu_context.h> | |
51 | #include <linux/license.h> | |
52 | #include <asm/sections.h> | |
53 | #include <linux/tracepoint.h> | |
54 | #include <linux/ftrace.h> | |
55 | #include <linux/async.h> | |
56 | #include <linux/percpu.h> | |
57 | #include <linux/kmemleak.h> | |
58 | ||
59 | #define CREATE_TRACE_POINTS | |
60 | #include <trace/events/module.h> | |
61 | ||
62 | #if 0 | |
63 | #define DEBUGP printk | |
64 | #else | |
65 | #define DEBUGP(fmt , a...) | |
66 | #endif | |
67 | ||
68 | #ifndef ARCH_SHF_SMALL | |
69 | #define ARCH_SHF_SMALL 0 | |
70 | #endif | |
71 | ||
72 | /* If this is set, the section belongs in the init part of the module */ | |
73 | #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) | |
74 | ||
75 | /* List of modules, protected by module_mutex or preempt_disable | |
76 | * (delete uses stop_machine/add uses RCU list operations). */ | |
77 | DEFINE_MUTEX(module_mutex); | |
78 | EXPORT_SYMBOL_GPL(module_mutex); | |
79 | static LIST_HEAD(modules); | |
80 | #ifdef CONFIG_KGDB_KDB | |
81 | struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ | |
82 | #endif /* CONFIG_KGDB_KDB */ | |
83 | ||
84 | ||
85 | /* Block module loading/unloading? */ | |
86 | int modules_disabled = 0; | |
87 | ||
88 | /* Waiting for a module to finish initializing? */ | |
89 | static DECLARE_WAIT_QUEUE_HEAD(module_wq); | |
90 | ||
91 | static BLOCKING_NOTIFIER_HEAD(module_notify_list); | |
92 | ||
93 | /* Bounds of module allocation, for speeding __module_address */ | |
94 | static unsigned long module_addr_min = -1UL, module_addr_max = 0; | |
95 | ||
96 | int register_module_notifier(struct notifier_block * nb) | |
97 | { | |
98 | return blocking_notifier_chain_register(&module_notify_list, nb); | |
99 | } | |
100 | EXPORT_SYMBOL(register_module_notifier); | |
101 | ||
102 | int unregister_module_notifier(struct notifier_block * nb) | |
103 | { | |
104 | return blocking_notifier_chain_unregister(&module_notify_list, nb); | |
105 | } | |
106 | EXPORT_SYMBOL(unregister_module_notifier); | |
107 | ||
108 | /* We require a truly strong try_module_get(): 0 means failure due to | |
109 | ongoing or failed initialization etc. */ | |
110 | static inline int strong_try_module_get(struct module *mod) | |
111 | { | |
112 | if (mod && mod->state == MODULE_STATE_COMING) | |
113 | return -EBUSY; | |
114 | if (try_module_get(mod)) | |
115 | return 0; | |
116 | else | |
117 | return -ENOENT; | |
118 | } | |
119 | ||
120 | static inline void add_taint_module(struct module *mod, unsigned flag) | |
121 | { | |
122 | add_taint(flag); | |
123 | mod->taints |= (1U << flag); | |
124 | } | |
125 | ||
126 | /* | |
127 | * A thread that wants to hold a reference to a module only while it | |
128 | * is running can call this to safely exit. nfsd and lockd use this. | |
129 | */ | |
130 | void __module_put_and_exit(struct module *mod, long code) | |
131 | { | |
132 | module_put(mod); | |
133 | do_exit(code); | |
134 | } | |
135 | EXPORT_SYMBOL(__module_put_and_exit); | |
136 | ||
137 | /* Find a module section: 0 means not found. */ | |
138 | static unsigned int find_sec(Elf_Ehdr *hdr, | |
139 | Elf_Shdr *sechdrs, | |
140 | const char *secstrings, | |
141 | const char *name) | |
142 | { | |
143 | unsigned int i; | |
144 | ||
145 | for (i = 1; i < hdr->e_shnum; i++) | |
146 | /* Alloc bit cleared means "ignore it." */ | |
147 | if ((sechdrs[i].sh_flags & SHF_ALLOC) | |
148 | && strcmp(secstrings+sechdrs[i].sh_name, name) == 0) | |
149 | return i; | |
150 | return 0; | |
151 | } | |
152 | ||
153 | /* Find a module section, or NULL. */ | |
154 | static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs, | |
155 | const char *secstrings, const char *name) | |
156 | { | |
157 | /* Section 0 has sh_addr 0. */ | |
158 | return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr; | |
159 | } | |
160 | ||
161 | /* Find a module section, or NULL. Fill in number of "objects" in section. */ | |
162 | static void *section_objs(Elf_Ehdr *hdr, | |
163 | Elf_Shdr *sechdrs, | |
164 | const char *secstrings, | |
165 | const char *name, | |
166 | size_t object_size, | |
167 | unsigned int *num) | |
168 | { | |
169 | unsigned int sec = find_sec(hdr, sechdrs, secstrings, name); | |
170 | ||
171 | /* Section 0 has sh_addr 0 and sh_size 0. */ | |
172 | *num = sechdrs[sec].sh_size / object_size; | |
173 | return (void *)sechdrs[sec].sh_addr; | |
174 | } | |
175 | ||
176 | /* Provided by the linker */ | |
177 | extern const struct kernel_symbol __start___ksymtab[]; | |
178 | extern const struct kernel_symbol __stop___ksymtab[]; | |
179 | extern const struct kernel_symbol __start___ksymtab_gpl[]; | |
180 | extern const struct kernel_symbol __stop___ksymtab_gpl[]; | |
181 | extern const struct kernel_symbol __start___ksymtab_gpl_future[]; | |
182 | extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; | |
183 | extern const unsigned long __start___kcrctab[]; | |
184 | extern const unsigned long __start___kcrctab_gpl[]; | |
185 | extern const unsigned long __start___kcrctab_gpl_future[]; | |
186 | #ifdef CONFIG_UNUSED_SYMBOLS | |
187 | extern const struct kernel_symbol __start___ksymtab_unused[]; | |
188 | extern const struct kernel_symbol __stop___ksymtab_unused[]; | |
189 | extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; | |
190 | extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; | |
191 | extern const unsigned long __start___kcrctab_unused[]; | |
192 | extern const unsigned long __start___kcrctab_unused_gpl[]; | |
193 | #endif | |
194 | ||
195 | #ifndef CONFIG_MODVERSIONS | |
196 | #define symversion(base, idx) NULL | |
197 | #else | |
198 | #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL) | |
199 | #endif | |
200 | ||
201 | static bool each_symbol_in_section(const struct symsearch *arr, | |
202 | unsigned int arrsize, | |
203 | struct module *owner, | |
204 | bool (*fn)(const struct symsearch *syms, | |
205 | struct module *owner, | |
206 | unsigned int symnum, void *data), | |
207 | void *data) | |
208 | { | |
209 | unsigned int i, j; | |
210 | ||
211 | for (j = 0; j < arrsize; j++) { | |
212 | for (i = 0; i < arr[j].stop - arr[j].start; i++) | |
213 | if (fn(&arr[j], owner, i, data)) | |
214 | return true; | |
215 | } | |
216 | ||
217 | return false; | |
218 | } | |
219 | ||
220 | /* Returns true as soon as fn returns true, otherwise false. */ | |
221 | bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner, | |
222 | unsigned int symnum, void *data), void *data) | |
223 | { | |
224 | struct module *mod; | |
225 | const struct symsearch arr[] = { | |
226 | { __start___ksymtab, __stop___ksymtab, __start___kcrctab, | |
227 | NOT_GPL_ONLY, false }, | |
228 | { __start___ksymtab_gpl, __stop___ksymtab_gpl, | |
229 | __start___kcrctab_gpl, | |
230 | GPL_ONLY, false }, | |
231 | { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future, | |
232 | __start___kcrctab_gpl_future, | |
233 | WILL_BE_GPL_ONLY, false }, | |
234 | #ifdef CONFIG_UNUSED_SYMBOLS | |
235 | { __start___ksymtab_unused, __stop___ksymtab_unused, | |
236 | __start___kcrctab_unused, | |
237 | NOT_GPL_ONLY, true }, | |
238 | { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl, | |
239 | __start___kcrctab_unused_gpl, | |
240 | GPL_ONLY, true }, | |
241 | #endif | |
242 | }; | |
243 | ||
244 | if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data)) | |
245 | return true; | |
246 | ||
247 | list_for_each_entry_rcu(mod, &modules, list) { | |
248 | struct symsearch arr[] = { | |
249 | { mod->syms, mod->syms + mod->num_syms, mod->crcs, | |
250 | NOT_GPL_ONLY, false }, | |
251 | { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, | |
252 | mod->gpl_crcs, | |
253 | GPL_ONLY, false }, | |
254 | { mod->gpl_future_syms, | |
255 | mod->gpl_future_syms + mod->num_gpl_future_syms, | |
256 | mod->gpl_future_crcs, | |
257 | WILL_BE_GPL_ONLY, false }, | |
258 | #ifdef CONFIG_UNUSED_SYMBOLS | |
259 | { mod->unused_syms, | |
260 | mod->unused_syms + mod->num_unused_syms, | |
261 | mod->unused_crcs, | |
262 | NOT_GPL_ONLY, true }, | |
263 | { mod->unused_gpl_syms, | |
264 | mod->unused_gpl_syms + mod->num_unused_gpl_syms, | |
265 | mod->unused_gpl_crcs, | |
266 | GPL_ONLY, true }, | |
267 | #endif | |
268 | }; | |
269 | ||
270 | if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data)) | |
271 | return true; | |
272 | } | |
273 | return false; | |
274 | } | |
275 | EXPORT_SYMBOL_GPL(each_symbol); | |
276 | ||
277 | struct find_symbol_arg { | |
278 | /* Input */ | |
279 | const char *name; | |
280 | bool gplok; | |
281 | bool warn; | |
282 | ||
283 | /* Output */ | |
284 | struct module *owner; | |
285 | const unsigned long *crc; | |
286 | const struct kernel_symbol *sym; | |
287 | }; | |
288 | ||
289 | static bool find_symbol_in_section(const struct symsearch *syms, | |
290 | struct module *owner, | |
291 | unsigned int symnum, void *data) | |
292 | { | |
293 | struct find_symbol_arg *fsa = data; | |
294 | ||
295 | if (strcmp(syms->start[symnum].name, fsa->name) != 0) | |
296 | return false; | |
297 | ||
298 | if (!fsa->gplok) { | |
299 | if (syms->licence == GPL_ONLY) | |
300 | return false; | |
301 | if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) { | |
302 | printk(KERN_WARNING "Symbol %s is being used " | |
303 | "by a non-GPL module, which will not " | |
304 | "be allowed in the future\n", fsa->name); | |
305 | printk(KERN_WARNING "Please see the file " | |
306 | "Documentation/feature-removal-schedule.txt " | |
307 | "in the kernel source tree for more details.\n"); | |
308 | } | |
309 | } | |
310 | ||
311 | #ifdef CONFIG_UNUSED_SYMBOLS | |
312 | if (syms->unused && fsa->warn) { | |
313 | printk(KERN_WARNING "Symbol %s is marked as UNUSED, " | |
314 | "however this module is using it.\n", fsa->name); | |
315 | printk(KERN_WARNING | |
316 | "This symbol will go away in the future.\n"); | |
317 | printk(KERN_WARNING | |
318 | "Please evalute if this is the right api to use and if " | |
319 | "it really is, submit a report the linux kernel " | |
320 | "mailinglist together with submitting your code for " | |
321 | "inclusion.\n"); | |
322 | } | |
323 | #endif | |
324 | ||
325 | fsa->owner = owner; | |
326 | fsa->crc = symversion(syms->crcs, symnum); | |
327 | fsa->sym = &syms->start[symnum]; | |
328 | return true; | |
329 | } | |
330 | ||
331 | /* Find a symbol and return it, along with, (optional) crc and | |
332 | * (optional) module which owns it */ | |
333 | const struct kernel_symbol *find_symbol(const char *name, | |
334 | struct module **owner, | |
335 | const unsigned long **crc, | |
336 | bool gplok, | |
337 | bool warn) | |
338 | { | |
339 | struct find_symbol_arg fsa; | |
340 | ||
341 | fsa.name = name; | |
342 | fsa.gplok = gplok; | |
343 | fsa.warn = warn; | |
344 | ||
345 | if (each_symbol(find_symbol_in_section, &fsa)) { | |
346 | if (owner) | |
347 | *owner = fsa.owner; | |
348 | if (crc) | |
349 | *crc = fsa.crc; | |
350 | return fsa.sym; | |
351 | } | |
352 | ||
353 | DEBUGP("Failed to find symbol %s\n", name); | |
354 | return NULL; | |
355 | } | |
356 | EXPORT_SYMBOL_GPL(find_symbol); | |
357 | ||
358 | /* Search for module by name: must hold module_mutex. */ | |
359 | struct module *find_module(const char *name) | |
360 | { | |
361 | struct module *mod; | |
362 | ||
363 | list_for_each_entry(mod, &modules, list) { | |
364 | if (strcmp(mod->name, name) == 0) | |
365 | return mod; | |
366 | } | |
367 | return NULL; | |
368 | } | |
369 | EXPORT_SYMBOL_GPL(find_module); | |
370 | ||
371 | #ifdef CONFIG_SMP | |
372 | ||
373 | static inline void __percpu *mod_percpu(struct module *mod) | |
374 | { | |
375 | return mod->percpu; | |
376 | } | |
377 | ||
378 | static int percpu_modalloc(struct module *mod, | |
379 | unsigned long size, unsigned long align) | |
380 | { | |
381 | if (align > PAGE_SIZE) { | |
382 | printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n", | |
383 | mod->name, align, PAGE_SIZE); | |
384 | align = PAGE_SIZE; | |
385 | } | |
386 | ||
387 | mod->percpu = __alloc_reserved_percpu(size, align); | |
388 | if (!mod->percpu) { | |
389 | printk(KERN_WARNING | |
390 | "Could not allocate %lu bytes percpu data\n", size); | |
391 | return -ENOMEM; | |
392 | } | |
393 | mod->percpu_size = size; | |
394 | return 0; | |
395 | } | |
396 | ||
397 | static void percpu_modfree(struct module *mod) | |
398 | { | |
399 | free_percpu(mod->percpu); | |
400 | } | |
401 | ||
402 | static unsigned int find_pcpusec(Elf_Ehdr *hdr, | |
403 | Elf_Shdr *sechdrs, | |
404 | const char *secstrings) | |
405 | { | |
406 | return find_sec(hdr, sechdrs, secstrings, ".data..percpu"); | |
407 | } | |
408 | ||
409 | static void percpu_modcopy(struct module *mod, | |
410 | const void *from, unsigned long size) | |
411 | { | |
412 | int cpu; | |
413 | ||
414 | for_each_possible_cpu(cpu) | |
415 | memcpy(per_cpu_ptr(mod->percpu, cpu), from, size); | |
416 | } | |
417 | ||
418 | /** | |
419 | * is_module_percpu_address - test whether address is from module static percpu | |
420 | * @addr: address to test | |
421 | * | |
422 | * Test whether @addr belongs to module static percpu area. | |
423 | * | |
424 | * RETURNS: | |
425 | * %true if @addr is from module static percpu area | |
426 | */ | |
427 | bool is_module_percpu_address(unsigned long addr) | |
428 | { | |
429 | struct module *mod; | |
430 | unsigned int cpu; | |
431 | ||
432 | preempt_disable(); | |
433 | ||
434 | list_for_each_entry_rcu(mod, &modules, list) { | |
435 | if (!mod->percpu_size) | |
436 | continue; | |
437 | for_each_possible_cpu(cpu) { | |
438 | void *start = per_cpu_ptr(mod->percpu, cpu); | |
439 | ||
440 | if ((void *)addr >= start && | |
441 | (void *)addr < start + mod->percpu_size) { | |
442 | preempt_enable(); | |
443 | return true; | |
444 | } | |
445 | } | |
446 | } | |
447 | ||
448 | preempt_enable(); | |
449 | return false; | |
450 | } | |
451 | ||
452 | #else /* ... !CONFIG_SMP */ | |
453 | ||
454 | static inline void __percpu *mod_percpu(struct module *mod) | |
455 | { | |
456 | return NULL; | |
457 | } | |
458 | static inline int percpu_modalloc(struct module *mod, | |
459 | unsigned long size, unsigned long align) | |
460 | { | |
461 | return -ENOMEM; | |
462 | } | |
463 | static inline void percpu_modfree(struct module *mod) | |
464 | { | |
465 | } | |
466 | static inline unsigned int find_pcpusec(Elf_Ehdr *hdr, | |
467 | Elf_Shdr *sechdrs, | |
468 | const char *secstrings) | |
469 | { | |
470 | return 0; | |
471 | } | |
472 | static inline void percpu_modcopy(struct module *mod, | |
473 | const void *from, unsigned long size) | |
474 | { | |
475 | /* pcpusec should be 0, and size of that section should be 0. */ | |
476 | BUG_ON(size != 0); | |
477 | } | |
478 | bool is_module_percpu_address(unsigned long addr) | |
479 | { | |
480 | return false; | |
481 | } | |
482 | ||
483 | #endif /* CONFIG_SMP */ | |
484 | ||
485 | #define MODINFO_ATTR(field) \ | |
486 | static void setup_modinfo_##field(struct module *mod, const char *s) \ | |
487 | { \ | |
488 | mod->field = kstrdup(s, GFP_KERNEL); \ | |
489 | } \ | |
490 | static ssize_t show_modinfo_##field(struct module_attribute *mattr, \ | |
491 | struct module *mod, char *buffer) \ | |
492 | { \ | |
493 | return sprintf(buffer, "%s\n", mod->field); \ | |
494 | } \ | |
495 | static int modinfo_##field##_exists(struct module *mod) \ | |
496 | { \ | |
497 | return mod->field != NULL; \ | |
498 | } \ | |
499 | static void free_modinfo_##field(struct module *mod) \ | |
500 | { \ | |
501 | kfree(mod->field); \ | |
502 | mod->field = NULL; \ | |
503 | } \ | |
504 | static struct module_attribute modinfo_##field = { \ | |
505 | .attr = { .name = __stringify(field), .mode = 0444 }, \ | |
506 | .show = show_modinfo_##field, \ | |
507 | .setup = setup_modinfo_##field, \ | |
508 | .test = modinfo_##field##_exists, \ | |
509 | .free = free_modinfo_##field, \ | |
510 | }; | |
511 | ||
512 | MODINFO_ATTR(version); | |
513 | MODINFO_ATTR(srcversion); | |
514 | ||
515 | static char last_unloaded_module[MODULE_NAME_LEN+1]; | |
516 | ||
517 | #ifdef CONFIG_MODULE_UNLOAD | |
518 | ||
519 | EXPORT_TRACEPOINT_SYMBOL(module_get); | |
520 | ||
521 | /* Init the unload section of the module. */ | |
522 | static void module_unload_init(struct module *mod) | |
523 | { | |
524 | int cpu; | |
525 | ||
526 | INIT_LIST_HEAD(&mod->source_list); | |
527 | INIT_LIST_HEAD(&mod->target_list); | |
528 | for_each_possible_cpu(cpu) { | |
529 | per_cpu_ptr(mod->refptr, cpu)->incs = 0; | |
530 | per_cpu_ptr(mod->refptr, cpu)->decs = 0; | |
531 | } | |
532 | ||
533 | /* Hold reference count during initialization. */ | |
534 | __this_cpu_write(mod->refptr->incs, 1); | |
535 | /* Backwards compatibility macros put refcount during init. */ | |
536 | mod->waiter = current; | |
537 | } | |
538 | ||
539 | /* Does a already use b? */ | |
540 | static int already_uses(struct module *a, struct module *b) | |
541 | { | |
542 | struct module_use *use; | |
543 | ||
544 | list_for_each_entry(use, &b->source_list, source_list) { | |
545 | if (use->source == a) { | |
546 | DEBUGP("%s uses %s!\n", a->name, b->name); | |
547 | return 1; | |
548 | } | |
549 | } | |
550 | DEBUGP("%s does not use %s!\n", a->name, b->name); | |
551 | return 0; | |
552 | } | |
553 | ||
554 | /* | |
555 | * Module a uses b | |
556 | * - we add 'a' as a "source", 'b' as a "target" of module use | |
557 | * - the module_use is added to the list of 'b' sources (so | |
558 | * 'b' can walk the list to see who sourced them), and of 'a' | |
559 | * targets (so 'a' can see what modules it targets). | |
560 | */ | |
561 | static int add_module_usage(struct module *a, struct module *b) | |
562 | { | |
563 | int no_warn; | |
564 | struct module_use *use; | |
565 | ||
566 | DEBUGP("Allocating new usage for %s.\n", a->name); | |
567 | use = kmalloc(sizeof(*use), GFP_ATOMIC); | |
568 | if (!use) { | |
569 | printk(KERN_WARNING "%s: out of memory loading\n", a->name); | |
570 | return -ENOMEM; | |
571 | } | |
572 | ||
573 | use->source = a; | |
574 | use->target = b; | |
575 | list_add(&use->source_list, &b->source_list); | |
576 | list_add(&use->target_list, &a->target_list); | |
577 | no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name); | |
578 | return 0; | |
579 | } | |
580 | ||
581 | /* Module a uses b */ | |
582 | int use_module(struct module *a, struct module *b) | |
583 | { | |
584 | int err; | |
585 | ||
586 | if (b == NULL || already_uses(a, b)) return 1; | |
587 | ||
588 | /* If we're interrupted or time out, we fail. */ | |
589 | if (wait_event_interruptible_timeout( | |
590 | module_wq, (err = strong_try_module_get(b)) != -EBUSY, | |
591 | 30 * HZ) <= 0) { | |
592 | printk("%s: gave up waiting for init of module %s.\n", | |
593 | a->name, b->name); | |
594 | return 0; | |
595 | } | |
596 | ||
597 | /* If strong_try_module_get() returned a different error, we fail. */ | |
598 | if (err) | |
599 | return 0; | |
600 | ||
601 | err = add_module_usage(a, b); | |
602 | if (err) { | |
603 | module_put(b); | |
604 | return 0; | |
605 | } | |
606 | return 1; | |
607 | } | |
608 | EXPORT_SYMBOL_GPL(use_module); | |
609 | ||
610 | /* Clear the unload stuff of the module. */ | |
611 | static void module_unload_free(struct module *mod) | |
612 | { | |
613 | struct module_use *use, *tmp; | |
614 | ||
615 | list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) { | |
616 | struct module *i = use->target; | |
617 | DEBUGP("%s unusing %s\n", mod->name, i->name); | |
618 | module_put(i); | |
619 | list_del(&use->source_list); | |
620 | list_del(&use->target_list); | |
621 | kfree(use); | |
622 | sysfs_remove_link(i->holders_dir, mod->name); | |
623 | } | |
624 | } | |
625 | ||
626 | #ifdef CONFIG_MODULE_FORCE_UNLOAD | |
627 | static inline int try_force_unload(unsigned int flags) | |
628 | { | |
629 | int ret = (flags & O_TRUNC); | |
630 | if (ret) | |
631 | add_taint(TAINT_FORCED_RMMOD); | |
632 | return ret; | |
633 | } | |
634 | #else | |
635 | static inline int try_force_unload(unsigned int flags) | |
636 | { | |
637 | return 0; | |
638 | } | |
639 | #endif /* CONFIG_MODULE_FORCE_UNLOAD */ | |
640 | ||
641 | struct stopref | |
642 | { | |
643 | struct module *mod; | |
644 | int flags; | |
645 | int *forced; | |
646 | }; | |
647 | ||
648 | /* Whole machine is stopped with interrupts off when this runs. */ | |
649 | static int __try_stop_module(void *_sref) | |
650 | { | |
651 | struct stopref *sref = _sref; | |
652 | ||
653 | /* If it's not unused, quit unless we're forcing. */ | |
654 | if (module_refcount(sref->mod) != 0) { | |
655 | if (!(*sref->forced = try_force_unload(sref->flags))) | |
656 | return -EWOULDBLOCK; | |
657 | } | |
658 | ||
659 | /* Mark it as dying. */ | |
660 | sref->mod->state = MODULE_STATE_GOING; | |
661 | return 0; | |
662 | } | |
663 | ||
664 | static int try_stop_module(struct module *mod, int flags, int *forced) | |
665 | { | |
666 | if (flags & O_NONBLOCK) { | |
667 | struct stopref sref = { mod, flags, forced }; | |
668 | ||
669 | return stop_machine(__try_stop_module, &sref, NULL); | |
670 | } else { | |
671 | /* We don't need to stop the machine for this. */ | |
672 | mod->state = MODULE_STATE_GOING; | |
673 | synchronize_sched(); | |
674 | return 0; | |
675 | } | |
676 | } | |
677 | ||
678 | unsigned int module_refcount(struct module *mod) | |
679 | { | |
680 | unsigned int incs = 0, decs = 0; | |
681 | int cpu; | |
682 | ||
683 | for_each_possible_cpu(cpu) | |
684 | decs += per_cpu_ptr(mod->refptr, cpu)->decs; | |
685 | /* | |
686 | * ensure the incs are added up after the decs. | |
687 | * module_put ensures incs are visible before decs with smp_wmb. | |
688 | * | |
689 | * This 2-count scheme avoids the situation where the refcount | |
690 | * for CPU0 is read, then CPU0 increments the module refcount, | |
691 | * then CPU1 drops that refcount, then the refcount for CPU1 is | |
692 | * read. We would record a decrement but not its corresponding | |
693 | * increment so we would see a low count (disaster). | |
694 | * | |
695 | * Rare situation? But module_refcount can be preempted, and we | |
696 | * might be tallying up 4096+ CPUs. So it is not impossible. | |
697 | */ | |
698 | smp_rmb(); | |
699 | for_each_possible_cpu(cpu) | |
700 | incs += per_cpu_ptr(mod->refptr, cpu)->incs; | |
701 | return incs - decs; | |
702 | } | |
703 | EXPORT_SYMBOL(module_refcount); | |
704 | ||
705 | /* This exists whether we can unload or not */ | |
706 | static void free_module(struct module *mod); | |
707 | ||
708 | static void wait_for_zero_refcount(struct module *mod) | |
709 | { | |
710 | /* Since we might sleep for some time, release the mutex first */ | |
711 | mutex_unlock(&module_mutex); | |
712 | for (;;) { | |
713 | DEBUGP("Looking at refcount...\n"); | |
714 | set_current_state(TASK_UNINTERRUPTIBLE); | |
715 | if (module_refcount(mod) == 0) | |
716 | break; | |
717 | schedule(); | |
718 | } | |
719 | current->state = TASK_RUNNING; | |
720 | mutex_lock(&module_mutex); | |
721 | } | |
722 | ||
723 | SYSCALL_DEFINE2(delete_module, const char __user *, name_user, | |
724 | unsigned int, flags) | |
725 | { | |
726 | struct module *mod; | |
727 | char name[MODULE_NAME_LEN]; | |
728 | int ret, forced = 0; | |
729 | ||
730 | if (!capable(CAP_SYS_MODULE) || modules_disabled) | |
731 | return -EPERM; | |
732 | ||
733 | if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) | |
734 | return -EFAULT; | |
735 | name[MODULE_NAME_LEN-1] = '\0'; | |
736 | ||
737 | if (mutex_lock_interruptible(&module_mutex) != 0) | |
738 | return -EINTR; | |
739 | ||
740 | mod = find_module(name); | |
741 | if (!mod) { | |
742 | ret = -ENOENT; | |
743 | goto out; | |
744 | } | |
745 | ||
746 | if (!list_empty(&mod->source_list)) { | |
747 | /* Other modules depend on us: get rid of them first. */ | |
748 | ret = -EWOULDBLOCK; | |
749 | goto out; | |
750 | } | |
751 | ||
752 | /* Doing init or already dying? */ | |
753 | if (mod->state != MODULE_STATE_LIVE) { | |
754 | /* FIXME: if (force), slam module count and wake up | |
755 | waiter --RR */ | |
756 | DEBUGP("%s already dying\n", mod->name); | |
757 | ret = -EBUSY; | |
758 | goto out; | |
759 | } | |
760 | ||
761 | /* If it has an init func, it must have an exit func to unload */ | |
762 | if (mod->init && !mod->exit) { | |
763 | forced = try_force_unload(flags); | |
764 | if (!forced) { | |
765 | /* This module can't be removed */ | |
766 | ret = -EBUSY; | |
767 | goto out; | |
768 | } | |
769 | } | |
770 | ||
771 | /* Set this up before setting mod->state */ | |
772 | mod->waiter = current; | |
773 | ||
774 | /* Stop the machine so refcounts can't move and disable module. */ | |
775 | ret = try_stop_module(mod, flags, &forced); | |
776 | if (ret != 0) | |
777 | goto out; | |
778 | ||
779 | /* Never wait if forced. */ | |
780 | if (!forced && module_refcount(mod) != 0) | |
781 | wait_for_zero_refcount(mod); | |
782 | ||
783 | mutex_unlock(&module_mutex); | |
784 | /* Final destruction now noone is using it. */ | |
785 | if (mod->exit != NULL) | |
786 | mod->exit(); | |
787 | blocking_notifier_call_chain(&module_notify_list, | |
788 | MODULE_STATE_GOING, mod); | |
789 | async_synchronize_full(); | |
790 | mutex_lock(&module_mutex); | |
791 | /* Store the name of the last unloaded module for diagnostic purposes */ | |
792 | strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); | |
793 | ddebug_remove_module(mod->name); | |
794 | free_module(mod); | |
795 | ||
796 | out: | |
797 | mutex_unlock(&module_mutex); | |
798 | return ret; | |
799 | } | |
800 | ||
801 | static inline void print_unload_info(struct seq_file *m, struct module *mod) | |
802 | { | |
803 | struct module_use *use; | |
804 | int printed_something = 0; | |
805 | ||
806 | seq_printf(m, " %u ", module_refcount(mod)); | |
807 | ||
808 | /* Always include a trailing , so userspace can differentiate | |
809 | between this and the old multi-field proc format. */ | |
810 | list_for_each_entry(use, &mod->source_list, source_list) { | |
811 | printed_something = 1; | |
812 | seq_printf(m, "%s,", use->source->name); | |
813 | } | |
814 | ||
815 | if (mod->init != NULL && mod->exit == NULL) { | |
816 | printed_something = 1; | |
817 | seq_printf(m, "[permanent],"); | |
818 | } | |
819 | ||
820 | if (!printed_something) | |
821 | seq_printf(m, "-"); | |
822 | } | |
823 | ||
824 | void __symbol_put(const char *symbol) | |
825 | { | |
826 | struct module *owner; | |
827 | ||
828 | preempt_disable(); | |
829 | if (!find_symbol(symbol, &owner, NULL, true, false)) | |
830 | BUG(); | |
831 | module_put(owner); | |
832 | preempt_enable(); | |
833 | } | |
834 | EXPORT_SYMBOL(__symbol_put); | |
835 | ||
836 | /* Note this assumes addr is a function, which it currently always is. */ | |
837 | void symbol_put_addr(void *addr) | |
838 | { | |
839 | struct module *modaddr; | |
840 | unsigned long a = (unsigned long)dereference_function_descriptor(addr); | |
841 | ||
842 | if (core_kernel_text(a)) | |
843 | return; | |
844 | ||
845 | /* module_text_address is safe here: we're supposed to have reference | |
846 | * to module from symbol_get, so it can't go away. */ | |
847 | modaddr = __module_text_address(a); | |
848 | BUG_ON(!modaddr); | |
849 | module_put(modaddr); | |
850 | } | |
851 | EXPORT_SYMBOL_GPL(symbol_put_addr); | |
852 | ||
853 | static ssize_t show_refcnt(struct module_attribute *mattr, | |
854 | struct module *mod, char *buffer) | |
855 | { | |
856 | return sprintf(buffer, "%u\n", module_refcount(mod)); | |
857 | } | |
858 | ||
859 | static struct module_attribute refcnt = { | |
860 | .attr = { .name = "refcnt", .mode = 0444 }, | |
861 | .show = show_refcnt, | |
862 | }; | |
863 | ||
864 | void module_put(struct module *module) | |
865 | { | |
866 | if (module) { | |
867 | preempt_disable(); | |
868 | smp_wmb(); /* see comment in module_refcount */ | |
869 | __this_cpu_inc(module->refptr->decs); | |
870 | ||
871 | trace_module_put(module, _RET_IP_); | |
872 | /* Maybe they're waiting for us to drop reference? */ | |
873 | if (unlikely(!module_is_live(module))) | |
874 | wake_up_process(module->waiter); | |
875 | preempt_enable(); | |
876 | } | |
877 | } | |
878 | EXPORT_SYMBOL(module_put); | |
879 | ||
880 | #else /* !CONFIG_MODULE_UNLOAD */ | |
881 | static inline void print_unload_info(struct seq_file *m, struct module *mod) | |
882 | { | |
883 | /* We don't know the usage count, or what modules are using. */ | |
884 | seq_printf(m, " - -"); | |
885 | } | |
886 | ||
887 | static inline void module_unload_free(struct module *mod) | |
888 | { | |
889 | } | |
890 | ||
891 | int use_module(struct module *a, struct module *b) | |
892 | { | |
893 | return strong_try_module_get(b) == 0; | |
894 | } | |
895 | EXPORT_SYMBOL_GPL(use_module); | |
896 | ||
897 | static inline void module_unload_init(struct module *mod) | |
898 | { | |
899 | } | |
900 | #endif /* CONFIG_MODULE_UNLOAD */ | |
901 | ||
902 | static ssize_t show_initstate(struct module_attribute *mattr, | |
903 | struct module *mod, char *buffer) | |
904 | { | |
905 | const char *state = "unknown"; | |
906 | ||
907 | switch (mod->state) { | |
908 | case MODULE_STATE_LIVE: | |
909 | state = "live"; | |
910 | break; | |
911 | case MODULE_STATE_COMING: | |
912 | state = "coming"; | |
913 | break; | |
914 | case MODULE_STATE_GOING: | |
915 | state = "going"; | |
916 | break; | |
917 | } | |
918 | return sprintf(buffer, "%s\n", state); | |
919 | } | |
920 | ||
921 | static struct module_attribute initstate = { | |
922 | .attr = { .name = "initstate", .mode = 0444 }, | |
923 | .show = show_initstate, | |
924 | }; | |
925 | ||
926 | static struct module_attribute *modinfo_attrs[] = { | |
927 | &modinfo_version, | |
928 | &modinfo_srcversion, | |
929 | &initstate, | |
930 | #ifdef CONFIG_MODULE_UNLOAD | |
931 | &refcnt, | |
932 | #endif | |
933 | NULL, | |
934 | }; | |
935 | ||
936 | static const char vermagic[] = VERMAGIC_STRING; | |
937 | ||
938 | static int try_to_force_load(struct module *mod, const char *reason) | |
939 | { | |
940 | #ifdef CONFIG_MODULE_FORCE_LOAD | |
941 | if (!test_taint(TAINT_FORCED_MODULE)) | |
942 | printk(KERN_WARNING "%s: %s: kernel tainted.\n", | |
943 | mod->name, reason); | |
944 | add_taint_module(mod, TAINT_FORCED_MODULE); | |
945 | return 0; | |
946 | #else | |
947 | return -ENOEXEC; | |
948 | #endif | |
949 | } | |
950 | ||
951 | #ifdef CONFIG_MODVERSIONS | |
952 | /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */ | |
953 | static unsigned long maybe_relocated(unsigned long crc, | |
954 | const struct module *crc_owner) | |
955 | { | |
956 | #ifdef ARCH_RELOCATES_KCRCTAB | |
957 | if (crc_owner == NULL) | |
958 | return crc - (unsigned long)reloc_start; | |
959 | #endif | |
960 | return crc; | |
961 | } | |
962 | ||
963 | static int check_version(Elf_Shdr *sechdrs, | |
964 | unsigned int versindex, | |
965 | const char *symname, | |
966 | struct module *mod, | |
967 | const unsigned long *crc, | |
968 | const struct module *crc_owner) | |
969 | { | |
970 | unsigned int i, num_versions; | |
971 | struct modversion_info *versions; | |
972 | ||
973 | /* Exporting module didn't supply crcs? OK, we're already tainted. */ | |
974 | if (!crc) | |
975 | return 1; | |
976 | ||
977 | /* No versions at all? modprobe --force does this. */ | |
978 | if (versindex == 0) | |
979 | return try_to_force_load(mod, symname) == 0; | |
980 | ||
981 | versions = (void *) sechdrs[versindex].sh_addr; | |
982 | num_versions = sechdrs[versindex].sh_size | |
983 | / sizeof(struct modversion_info); | |
984 | ||
985 | for (i = 0; i < num_versions; i++) { | |
986 | if (strcmp(versions[i].name, symname) != 0) | |
987 | continue; | |
988 | ||
989 | if (versions[i].crc == maybe_relocated(*crc, crc_owner)) | |
990 | return 1; | |
991 | DEBUGP("Found checksum %lX vs module %lX\n", | |
992 | maybe_relocated(*crc, crc_owner), versions[i].crc); | |
993 | goto bad_version; | |
994 | } | |
995 | ||
996 | printk(KERN_WARNING "%s: no symbol version for %s\n", | |
997 | mod->name, symname); | |
998 | return 0; | |
999 | ||
1000 | bad_version: | |
1001 | printk("%s: disagrees about version of symbol %s\n", | |
1002 | mod->name, symname); | |
1003 | return 0; | |
1004 | } | |
1005 | ||
1006 | static inline int check_modstruct_version(Elf_Shdr *sechdrs, | |
1007 | unsigned int versindex, | |
1008 | struct module *mod) | |
1009 | { | |
1010 | const unsigned long *crc; | |
1011 | ||
1012 | if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL, | |
1013 | &crc, true, false)) | |
1014 | BUG(); | |
1015 | return check_version(sechdrs, versindex, "module_layout", mod, crc, | |
1016 | NULL); | |
1017 | } | |
1018 | ||
1019 | /* First part is kernel version, which we ignore if module has crcs. */ | |
1020 | static inline int same_magic(const char *amagic, const char *bmagic, | |
1021 | bool has_crcs) | |
1022 | { | |
1023 | if (has_crcs) { | |
1024 | amagic += strcspn(amagic, " "); | |
1025 | bmagic += strcspn(bmagic, " "); | |
1026 | } | |
1027 | return strcmp(amagic, bmagic) == 0; | |
1028 | } | |
1029 | #else | |
1030 | static inline int check_version(Elf_Shdr *sechdrs, | |
1031 | unsigned int versindex, | |
1032 | const char *symname, | |
1033 | struct module *mod, | |
1034 | const unsigned long *crc, | |
1035 | const struct module *crc_owner) | |
1036 | { | |
1037 | return 1; | |
1038 | } | |
1039 | ||
1040 | static inline int check_modstruct_version(Elf_Shdr *sechdrs, | |
1041 | unsigned int versindex, | |
1042 | struct module *mod) | |
1043 | { | |
1044 | return 1; | |
1045 | } | |
1046 | ||
1047 | static inline int same_magic(const char *amagic, const char *bmagic, | |
1048 | bool has_crcs) | |
1049 | { | |
1050 | return strcmp(amagic, bmagic) == 0; | |
1051 | } | |
1052 | #endif /* CONFIG_MODVERSIONS */ | |
1053 | ||
1054 | /* Resolve a symbol for this module. I.e. if we find one, record usage. | |
1055 | Must be holding module_mutex. */ | |
1056 | static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs, | |
1057 | unsigned int versindex, | |
1058 | const char *name, | |
1059 | struct module *mod) | |
1060 | { | |
1061 | struct module *owner; | |
1062 | const struct kernel_symbol *sym; | |
1063 | const unsigned long *crc; | |
1064 | ||
1065 | sym = find_symbol(name, &owner, &crc, | |
1066 | !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true); | |
1067 | /* use_module can fail due to OOM, | |
1068 | or module initialization or unloading */ | |
1069 | if (sym) { | |
1070 | if (!check_version(sechdrs, versindex, name, mod, crc, owner) | |
1071 | || !use_module(mod, owner)) | |
1072 | sym = NULL; | |
1073 | } | |
1074 | return sym; | |
1075 | } | |
1076 | ||
1077 | /* | |
1078 | * /sys/module/foo/sections stuff | |
1079 | * J. Corbet <corbet@lwn.net> | |
1080 | */ | |
1081 | #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS) | |
1082 | ||
1083 | static inline bool sect_empty(const Elf_Shdr *sect) | |
1084 | { | |
1085 | return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0; | |
1086 | } | |
1087 | ||
1088 | struct module_sect_attr | |
1089 | { | |
1090 | struct module_attribute mattr; | |
1091 | char *name; | |
1092 | unsigned long address; | |
1093 | }; | |
1094 | ||
1095 | struct module_sect_attrs | |
1096 | { | |
1097 | struct attribute_group grp; | |
1098 | unsigned int nsections; | |
1099 | struct module_sect_attr attrs[0]; | |
1100 | }; | |
1101 | ||
1102 | static ssize_t module_sect_show(struct module_attribute *mattr, | |
1103 | struct module *mod, char *buf) | |
1104 | { | |
1105 | struct module_sect_attr *sattr = | |
1106 | container_of(mattr, struct module_sect_attr, mattr); | |
1107 | return sprintf(buf, "0x%lx\n", sattr->address); | |
1108 | } | |
1109 | ||
1110 | static void free_sect_attrs(struct module_sect_attrs *sect_attrs) | |
1111 | { | |
1112 | unsigned int section; | |
1113 | ||
1114 | for (section = 0; section < sect_attrs->nsections; section++) | |
1115 | kfree(sect_attrs->attrs[section].name); | |
1116 | kfree(sect_attrs); | |
1117 | } | |
1118 | ||
1119 | static void add_sect_attrs(struct module *mod, unsigned int nsect, | |
1120 | char *secstrings, Elf_Shdr *sechdrs) | |
1121 | { | |
1122 | unsigned int nloaded = 0, i, size[2]; | |
1123 | struct module_sect_attrs *sect_attrs; | |
1124 | struct module_sect_attr *sattr; | |
1125 | struct attribute **gattr; | |
1126 | ||
1127 | /* Count loaded sections and allocate structures */ | |
1128 | for (i = 0; i < nsect; i++) | |
1129 | if (!sect_empty(&sechdrs[i])) | |
1130 | nloaded++; | |
1131 | size[0] = ALIGN(sizeof(*sect_attrs) | |
1132 | + nloaded * sizeof(sect_attrs->attrs[0]), | |
1133 | sizeof(sect_attrs->grp.attrs[0])); | |
1134 | size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]); | |
1135 | sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); | |
1136 | if (sect_attrs == NULL) | |
1137 | return; | |
1138 | ||
1139 | /* Setup section attributes. */ | |
1140 | sect_attrs->grp.name = "sections"; | |
1141 | sect_attrs->grp.attrs = (void *)sect_attrs + size[0]; | |
1142 | ||
1143 | sect_attrs->nsections = 0; | |
1144 | sattr = §_attrs->attrs[0]; | |
1145 | gattr = §_attrs->grp.attrs[0]; | |
1146 | for (i = 0; i < nsect; i++) { | |
1147 | if (sect_empty(&sechdrs[i])) | |
1148 | continue; | |
1149 | sattr->address = sechdrs[i].sh_addr; | |
1150 | sattr->name = kstrdup(secstrings + sechdrs[i].sh_name, | |
1151 | GFP_KERNEL); | |
1152 | if (sattr->name == NULL) | |
1153 | goto out; | |
1154 | sect_attrs->nsections++; | |
1155 | sysfs_attr_init(&sattr->mattr.attr); | |
1156 | sattr->mattr.show = module_sect_show; | |
1157 | sattr->mattr.store = NULL; | |
1158 | sattr->mattr.attr.name = sattr->name; | |
1159 | sattr->mattr.attr.mode = S_IRUGO; | |
1160 | *(gattr++) = &(sattr++)->mattr.attr; | |
1161 | } | |
1162 | *gattr = NULL; | |
1163 | ||
1164 | if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) | |
1165 | goto out; | |
1166 | ||
1167 | mod->sect_attrs = sect_attrs; | |
1168 | return; | |
1169 | out: | |
1170 | free_sect_attrs(sect_attrs); | |
1171 | } | |
1172 | ||
1173 | static void remove_sect_attrs(struct module *mod) | |
1174 | { | |
1175 | if (mod->sect_attrs) { | |
1176 | sysfs_remove_group(&mod->mkobj.kobj, | |
1177 | &mod->sect_attrs->grp); | |
1178 | /* We are positive that no one is using any sect attrs | |
1179 | * at this point. Deallocate immediately. */ | |
1180 | free_sect_attrs(mod->sect_attrs); | |
1181 | mod->sect_attrs = NULL; | |
1182 | } | |
1183 | } | |
1184 | ||
1185 | /* | |
1186 | * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. | |
1187 | */ | |
1188 | ||
1189 | struct module_notes_attrs { | |
1190 | struct kobject *dir; | |
1191 | unsigned int notes; | |
1192 | struct bin_attribute attrs[0]; | |
1193 | }; | |
1194 | ||
1195 | static ssize_t module_notes_read(struct file *filp, struct kobject *kobj, | |
1196 | struct bin_attribute *bin_attr, | |
1197 | char *buf, loff_t pos, size_t count) | |
1198 | { | |
1199 | /* | |
1200 | * The caller checked the pos and count against our size. | |
1201 | */ | |
1202 | memcpy(buf, bin_attr->private + pos, count); | |
1203 | return count; | |
1204 | } | |
1205 | ||
1206 | static void free_notes_attrs(struct module_notes_attrs *notes_attrs, | |
1207 | unsigned int i) | |
1208 | { | |
1209 | if (notes_attrs->dir) { | |
1210 | while (i-- > 0) | |
1211 | sysfs_remove_bin_file(notes_attrs->dir, | |
1212 | ¬es_attrs->attrs[i]); | |
1213 | kobject_put(notes_attrs->dir); | |
1214 | } | |
1215 | kfree(notes_attrs); | |
1216 | } | |
1217 | ||
1218 | static void add_notes_attrs(struct module *mod, unsigned int nsect, | |
1219 | char *secstrings, Elf_Shdr *sechdrs) | |
1220 | { | |
1221 | unsigned int notes, loaded, i; | |
1222 | struct module_notes_attrs *notes_attrs; | |
1223 | struct bin_attribute *nattr; | |
1224 | ||
1225 | /* failed to create section attributes, so can't create notes */ | |
1226 | if (!mod->sect_attrs) | |
1227 | return; | |
1228 | ||
1229 | /* Count notes sections and allocate structures. */ | |
1230 | notes = 0; | |
1231 | for (i = 0; i < nsect; i++) | |
1232 | if (!sect_empty(&sechdrs[i]) && | |
1233 | (sechdrs[i].sh_type == SHT_NOTE)) | |
1234 | ++notes; | |
1235 | ||
1236 | if (notes == 0) | |
1237 | return; | |
1238 | ||
1239 | notes_attrs = kzalloc(sizeof(*notes_attrs) | |
1240 | + notes * sizeof(notes_attrs->attrs[0]), | |
1241 | GFP_KERNEL); | |
1242 | if (notes_attrs == NULL) | |
1243 | return; | |
1244 | ||
1245 | notes_attrs->notes = notes; | |
1246 | nattr = ¬es_attrs->attrs[0]; | |
1247 | for (loaded = i = 0; i < nsect; ++i) { | |
1248 | if (sect_empty(&sechdrs[i])) | |
1249 | continue; | |
1250 | if (sechdrs[i].sh_type == SHT_NOTE) { | |
1251 | sysfs_bin_attr_init(nattr); | |
1252 | nattr->attr.name = mod->sect_attrs->attrs[loaded].name; | |
1253 | nattr->attr.mode = S_IRUGO; | |
1254 | nattr->size = sechdrs[i].sh_size; | |
1255 | nattr->private = (void *) sechdrs[i].sh_addr; | |
1256 | nattr->read = module_notes_read; | |
1257 | ++nattr; | |
1258 | } | |
1259 | ++loaded; | |
1260 | } | |
1261 | ||
1262 | notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); | |
1263 | if (!notes_attrs->dir) | |
1264 | goto out; | |
1265 | ||
1266 | for (i = 0; i < notes; ++i) | |
1267 | if (sysfs_create_bin_file(notes_attrs->dir, | |
1268 | ¬es_attrs->attrs[i])) | |
1269 | goto out; | |
1270 | ||
1271 | mod->notes_attrs = notes_attrs; | |
1272 | return; | |
1273 | ||
1274 | out: | |
1275 | free_notes_attrs(notes_attrs, i); | |
1276 | } | |
1277 | ||
1278 | static void remove_notes_attrs(struct module *mod) | |
1279 | { | |
1280 | if (mod->notes_attrs) | |
1281 | free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); | |
1282 | } | |
1283 | ||
1284 | #else | |
1285 | ||
1286 | static inline void add_sect_attrs(struct module *mod, unsigned int nsect, | |
1287 | char *sectstrings, Elf_Shdr *sechdrs) | |
1288 | { | |
1289 | } | |
1290 | ||
1291 | static inline void remove_sect_attrs(struct module *mod) | |
1292 | { | |
1293 | } | |
1294 | ||
1295 | static inline void add_notes_attrs(struct module *mod, unsigned int nsect, | |
1296 | char *sectstrings, Elf_Shdr *sechdrs) | |
1297 | { | |
1298 | } | |
1299 | ||
1300 | static inline void remove_notes_attrs(struct module *mod) | |
1301 | { | |
1302 | } | |
1303 | #endif | |
1304 | ||
1305 | #ifdef CONFIG_SYSFS | |
1306 | int module_add_modinfo_attrs(struct module *mod) | |
1307 | { | |
1308 | struct module_attribute *attr; | |
1309 | struct module_attribute *temp_attr; | |
1310 | int error = 0; | |
1311 | int i; | |
1312 | ||
1313 | mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * | |
1314 | (ARRAY_SIZE(modinfo_attrs) + 1)), | |
1315 | GFP_KERNEL); | |
1316 | if (!mod->modinfo_attrs) | |
1317 | return -ENOMEM; | |
1318 | ||
1319 | temp_attr = mod->modinfo_attrs; | |
1320 | for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) { | |
1321 | if (!attr->test || | |
1322 | (attr->test && attr->test(mod))) { | |
1323 | memcpy(temp_attr, attr, sizeof(*temp_attr)); | |
1324 | sysfs_attr_init(&temp_attr->attr); | |
1325 | error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr); | |
1326 | ++temp_attr; | |
1327 | } | |
1328 | } | |
1329 | return error; | |
1330 | } | |
1331 | ||
1332 | void module_remove_modinfo_attrs(struct module *mod) | |
1333 | { | |
1334 | struct module_attribute *attr; | |
1335 | int i; | |
1336 | ||
1337 | for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { | |
1338 | /* pick a field to test for end of list */ | |
1339 | if (!attr->attr.name) | |
1340 | break; | |
1341 | sysfs_remove_file(&mod->mkobj.kobj,&attr->attr); | |
1342 | if (attr->free) | |
1343 | attr->free(mod); | |
1344 | } | |
1345 | kfree(mod->modinfo_attrs); | |
1346 | } | |
1347 | ||
1348 | int mod_sysfs_init(struct module *mod) | |
1349 | { | |
1350 | int err; | |
1351 | struct kobject *kobj; | |
1352 | ||
1353 | if (!module_sysfs_initialized) { | |
1354 | printk(KERN_ERR "%s: module sysfs not initialized\n", | |
1355 | mod->name); | |
1356 | err = -EINVAL; | |
1357 | goto out; | |
1358 | } | |
1359 | ||
1360 | kobj = kset_find_obj(module_kset, mod->name); | |
1361 | if (kobj) { | |
1362 | printk(KERN_ERR "%s: module is already loaded\n", mod->name); | |
1363 | kobject_put(kobj); | |
1364 | err = -EINVAL; | |
1365 | goto out; | |
1366 | } | |
1367 | ||
1368 | mod->mkobj.mod = mod; | |
1369 | ||
1370 | memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); | |
1371 | mod->mkobj.kobj.kset = module_kset; | |
1372 | err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, | |
1373 | "%s", mod->name); | |
1374 | if (err) | |
1375 | kobject_put(&mod->mkobj.kobj); | |
1376 | ||
1377 | /* delay uevent until full sysfs population */ | |
1378 | out: | |
1379 | return err; | |
1380 | } | |
1381 | ||
1382 | int mod_sysfs_setup(struct module *mod, | |
1383 | struct kernel_param *kparam, | |
1384 | unsigned int num_params) | |
1385 | { | |
1386 | int err; | |
1387 | ||
1388 | mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); | |
1389 | if (!mod->holders_dir) { | |
1390 | err = -ENOMEM; | |
1391 | goto out_unreg; | |
1392 | } | |
1393 | ||
1394 | err = module_param_sysfs_setup(mod, kparam, num_params); | |
1395 | if (err) | |
1396 | goto out_unreg_holders; | |
1397 | ||
1398 | err = module_add_modinfo_attrs(mod); | |
1399 | if (err) | |
1400 | goto out_unreg_param; | |
1401 | ||
1402 | kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD); | |
1403 | return 0; | |
1404 | ||
1405 | out_unreg_param: | |
1406 | module_param_sysfs_remove(mod); | |
1407 | out_unreg_holders: | |
1408 | kobject_put(mod->holders_dir); | |
1409 | out_unreg: | |
1410 | kobject_put(&mod->mkobj.kobj); | |
1411 | return err; | |
1412 | } | |
1413 | ||
1414 | static void mod_sysfs_fini(struct module *mod) | |
1415 | { | |
1416 | kobject_put(&mod->mkobj.kobj); | |
1417 | } | |
1418 | ||
1419 | #else /* CONFIG_SYSFS */ | |
1420 | ||
1421 | static void mod_sysfs_fini(struct module *mod) | |
1422 | { | |
1423 | } | |
1424 | ||
1425 | #endif /* CONFIG_SYSFS */ | |
1426 | ||
1427 | static void mod_kobject_remove(struct module *mod) | |
1428 | { | |
1429 | module_remove_modinfo_attrs(mod); | |
1430 | module_param_sysfs_remove(mod); | |
1431 | kobject_put(mod->mkobj.drivers_dir); | |
1432 | kobject_put(mod->holders_dir); | |
1433 | mod_sysfs_fini(mod); | |
1434 | } | |
1435 | ||
1436 | /* | |
1437 | * unlink the module with the whole machine is stopped with interrupts off | |
1438 | * - this defends against kallsyms not taking locks | |
1439 | */ | |
1440 | static int __unlink_module(void *_mod) | |
1441 | { | |
1442 | struct module *mod = _mod; | |
1443 | list_del(&mod->list); | |
1444 | return 0; | |
1445 | } | |
1446 | ||
1447 | /* Free a module, remove from lists, etc (must hold module_mutex). */ | |
1448 | static void free_module(struct module *mod) | |
1449 | { | |
1450 | trace_module_free(mod); | |
1451 | ||
1452 | /* Delete from various lists */ | |
1453 | stop_machine(__unlink_module, mod, NULL); | |
1454 | remove_notes_attrs(mod); | |
1455 | remove_sect_attrs(mod); | |
1456 | mod_kobject_remove(mod); | |
1457 | ||
1458 | /* Arch-specific cleanup. */ | |
1459 | module_arch_cleanup(mod); | |
1460 | ||
1461 | /* Module unload stuff */ | |
1462 | module_unload_free(mod); | |
1463 | ||
1464 | /* Free any allocated parameters. */ | |
1465 | destroy_params(mod->kp, mod->num_kp); | |
1466 | ||
1467 | /* This may be NULL, but that's OK */ | |
1468 | module_free(mod, mod->module_init); | |
1469 | kfree(mod->args); | |
1470 | percpu_modfree(mod); | |
1471 | #if defined(CONFIG_MODULE_UNLOAD) | |
1472 | if (mod->refptr) | |
1473 | free_percpu(mod->refptr); | |
1474 | #endif | |
1475 | /* Free lock-classes: */ | |
1476 | lockdep_free_key_range(mod->module_core, mod->core_size); | |
1477 | ||
1478 | /* Finally, free the core (containing the module structure) */ | |
1479 | module_free(mod, mod->module_core); | |
1480 | ||
1481 | #ifdef CONFIG_MPU | |
1482 | update_protections(current->mm); | |
1483 | #endif | |
1484 | } | |
1485 | ||
1486 | void *__symbol_get(const char *symbol) | |
1487 | { | |
1488 | struct module *owner; | |
1489 | const struct kernel_symbol *sym; | |
1490 | ||
1491 | preempt_disable(); | |
1492 | sym = find_symbol(symbol, &owner, NULL, true, true); | |
1493 | if (sym && strong_try_module_get(owner)) | |
1494 | sym = NULL; | |
1495 | preempt_enable(); | |
1496 | ||
1497 | return sym ? (void *)sym->value : NULL; | |
1498 | } | |
1499 | EXPORT_SYMBOL_GPL(__symbol_get); | |
1500 | ||
1501 | /* | |
1502 | * Ensure that an exported symbol [global namespace] does not already exist | |
1503 | * in the kernel or in some other module's exported symbol table. | |
1504 | */ | |
1505 | static int verify_export_symbols(struct module *mod) | |
1506 | { | |
1507 | unsigned int i; | |
1508 | struct module *owner; | |
1509 | const struct kernel_symbol *s; | |
1510 | struct { | |
1511 | const struct kernel_symbol *sym; | |
1512 | unsigned int num; | |
1513 | } arr[] = { | |
1514 | { mod->syms, mod->num_syms }, | |
1515 | { mod->gpl_syms, mod->num_gpl_syms }, | |
1516 | { mod->gpl_future_syms, mod->num_gpl_future_syms }, | |
1517 | #ifdef CONFIG_UNUSED_SYMBOLS | |
1518 | { mod->unused_syms, mod->num_unused_syms }, | |
1519 | { mod->unused_gpl_syms, mod->num_unused_gpl_syms }, | |
1520 | #endif | |
1521 | }; | |
1522 | ||
1523 | for (i = 0; i < ARRAY_SIZE(arr); i++) { | |
1524 | for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) { | |
1525 | if (find_symbol(s->name, &owner, NULL, true, false)) { | |
1526 | printk(KERN_ERR | |
1527 | "%s: exports duplicate symbol %s" | |
1528 | " (owned by %s)\n", | |
1529 | mod->name, s->name, module_name(owner)); | |
1530 | return -ENOEXEC; | |
1531 | } | |
1532 | } | |
1533 | } | |
1534 | return 0; | |
1535 | } | |
1536 | ||
1537 | /* Change all symbols so that st_value encodes the pointer directly. */ | |
1538 | static int simplify_symbols(Elf_Shdr *sechdrs, | |
1539 | unsigned int symindex, | |
1540 | const char *strtab, | |
1541 | unsigned int versindex, | |
1542 | unsigned int pcpuindex, | |
1543 | struct module *mod) | |
1544 | { | |
1545 | Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr; | |
1546 | unsigned long secbase; | |
1547 | unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym); | |
1548 | int ret = 0; | |
1549 | const struct kernel_symbol *ksym; | |
1550 | ||
1551 | for (i = 1; i < n; i++) { | |
1552 | switch (sym[i].st_shndx) { | |
1553 | case SHN_COMMON: | |
1554 | /* We compiled with -fno-common. These are not | |
1555 | supposed to happen. */ | |
1556 | DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name); | |
1557 | printk("%s: please compile with -fno-common\n", | |
1558 | mod->name); | |
1559 | ret = -ENOEXEC; | |
1560 | break; | |
1561 | ||
1562 | case SHN_ABS: | |
1563 | /* Don't need to do anything */ | |
1564 | DEBUGP("Absolute symbol: 0x%08lx\n", | |
1565 | (long)sym[i].st_value); | |
1566 | break; | |
1567 | ||
1568 | case SHN_UNDEF: | |
1569 | ksym = resolve_symbol(sechdrs, versindex, | |
1570 | strtab + sym[i].st_name, mod); | |
1571 | /* Ok if resolved. */ | |
1572 | if (ksym) { | |
1573 | sym[i].st_value = ksym->value; | |
1574 | break; | |
1575 | } | |
1576 | ||
1577 | /* Ok if weak. */ | |
1578 | if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK) | |
1579 | break; | |
1580 | ||
1581 | printk(KERN_WARNING "%s: Unknown symbol %s\n", | |
1582 | mod->name, strtab + sym[i].st_name); | |
1583 | ret = -ENOENT; | |
1584 | break; | |
1585 | ||
1586 | default: | |
1587 | /* Divert to percpu allocation if a percpu var. */ | |
1588 | if (sym[i].st_shndx == pcpuindex) | |
1589 | secbase = (unsigned long)mod_percpu(mod); | |
1590 | else | |
1591 | secbase = sechdrs[sym[i].st_shndx].sh_addr; | |
1592 | sym[i].st_value += secbase; | |
1593 | break; | |
1594 | } | |
1595 | } | |
1596 | ||
1597 | return ret; | |
1598 | } | |
1599 | ||
1600 | /* Additional bytes needed by arch in front of individual sections */ | |
1601 | unsigned int __weak arch_mod_section_prepend(struct module *mod, | |
1602 | unsigned int section) | |
1603 | { | |
1604 | /* default implementation just returns zero */ | |
1605 | return 0; | |
1606 | } | |
1607 | ||
1608 | /* Update size with this section: return offset. */ | |
1609 | static long get_offset(struct module *mod, unsigned int *size, | |
1610 | Elf_Shdr *sechdr, unsigned int section) | |
1611 | { | |
1612 | long ret; | |
1613 | ||
1614 | *size += arch_mod_section_prepend(mod, section); | |
1615 | ret = ALIGN(*size, sechdr->sh_addralign ?: 1); | |
1616 | *size = ret + sechdr->sh_size; | |
1617 | return ret; | |
1618 | } | |
1619 | ||
1620 | /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld | |
1621 | might -- code, read-only data, read-write data, small data. Tally | |
1622 | sizes, and place the offsets into sh_entsize fields: high bit means it | |
1623 | belongs in init. */ | |
1624 | static void layout_sections(struct module *mod, | |
1625 | const Elf_Ehdr *hdr, | |
1626 | Elf_Shdr *sechdrs, | |
1627 | const char *secstrings) | |
1628 | { | |
1629 | static unsigned long const masks[][2] = { | |
1630 | /* NOTE: all executable code must be the first section | |
1631 | * in this array; otherwise modify the text_size | |
1632 | * finder in the two loops below */ | |
1633 | { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL }, | |
1634 | { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL }, | |
1635 | { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL }, | |
1636 | { ARCH_SHF_SMALL | SHF_ALLOC, 0 } | |
1637 | }; | |
1638 | unsigned int m, i; | |
1639 | ||
1640 | for (i = 0; i < hdr->e_shnum; i++) | |
1641 | sechdrs[i].sh_entsize = ~0UL; | |
1642 | ||
1643 | DEBUGP("Core section allocation order:\n"); | |
1644 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { | |
1645 | for (i = 0; i < hdr->e_shnum; ++i) { | |
1646 | Elf_Shdr *s = &sechdrs[i]; | |
1647 | ||
1648 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
1649 | || (s->sh_flags & masks[m][1]) | |
1650 | || s->sh_entsize != ~0UL | |
1651 | || strstarts(secstrings + s->sh_name, ".init")) | |
1652 | continue; | |
1653 | s->sh_entsize = get_offset(mod, &mod->core_size, s, i); | |
1654 | DEBUGP("\t%s\n", secstrings + s->sh_name); | |
1655 | } | |
1656 | if (m == 0) | |
1657 | mod->core_text_size = mod->core_size; | |
1658 | } | |
1659 | ||
1660 | DEBUGP("Init section allocation order:\n"); | |
1661 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { | |
1662 | for (i = 0; i < hdr->e_shnum; ++i) { | |
1663 | Elf_Shdr *s = &sechdrs[i]; | |
1664 | ||
1665 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
1666 | || (s->sh_flags & masks[m][1]) | |
1667 | || s->sh_entsize != ~0UL | |
1668 | || !strstarts(secstrings + s->sh_name, ".init")) | |
1669 | continue; | |
1670 | s->sh_entsize = (get_offset(mod, &mod->init_size, s, i) | |
1671 | | INIT_OFFSET_MASK); | |
1672 | DEBUGP("\t%s\n", secstrings + s->sh_name); | |
1673 | } | |
1674 | if (m == 0) | |
1675 | mod->init_text_size = mod->init_size; | |
1676 | } | |
1677 | } | |
1678 | ||
1679 | static void set_license(struct module *mod, const char *license) | |
1680 | { | |
1681 | if (!license) | |
1682 | license = "unspecified"; | |
1683 | ||
1684 | if (!license_is_gpl_compatible(license)) { | |
1685 | if (!test_taint(TAINT_PROPRIETARY_MODULE)) | |
1686 | printk(KERN_WARNING "%s: module license '%s' taints " | |
1687 | "kernel.\n", mod->name, license); | |
1688 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE); | |
1689 | } | |
1690 | } | |
1691 | ||
1692 | /* Parse tag=value strings from .modinfo section */ | |
1693 | static char *next_string(char *string, unsigned long *secsize) | |
1694 | { | |
1695 | /* Skip non-zero chars */ | |
1696 | while (string[0]) { | |
1697 | string++; | |
1698 | if ((*secsize)-- <= 1) | |
1699 | return NULL; | |
1700 | } | |
1701 | ||
1702 | /* Skip any zero padding. */ | |
1703 | while (!string[0]) { | |
1704 | string++; | |
1705 | if ((*secsize)-- <= 1) | |
1706 | return NULL; | |
1707 | } | |
1708 | return string; | |
1709 | } | |
1710 | ||
1711 | static char *get_modinfo(Elf_Shdr *sechdrs, | |
1712 | unsigned int info, | |
1713 | const char *tag) | |
1714 | { | |
1715 | char *p; | |
1716 | unsigned int taglen = strlen(tag); | |
1717 | unsigned long size = sechdrs[info].sh_size; | |
1718 | ||
1719 | for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) { | |
1720 | if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') | |
1721 | return p + taglen + 1; | |
1722 | } | |
1723 | return NULL; | |
1724 | } | |
1725 | ||
1726 | static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs, | |
1727 | unsigned int infoindex) | |
1728 | { | |
1729 | struct module_attribute *attr; | |
1730 | int i; | |
1731 | ||
1732 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
1733 | if (attr->setup) | |
1734 | attr->setup(mod, | |
1735 | get_modinfo(sechdrs, | |
1736 | infoindex, | |
1737 | attr->attr.name)); | |
1738 | } | |
1739 | } | |
1740 | ||
1741 | static void free_modinfo(struct module *mod) | |
1742 | { | |
1743 | struct module_attribute *attr; | |
1744 | int i; | |
1745 | ||
1746 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
1747 | if (attr->free) | |
1748 | attr->free(mod); | |
1749 | } | |
1750 | } | |
1751 | ||
1752 | #ifdef CONFIG_KALLSYMS | |
1753 | ||
1754 | /* lookup symbol in given range of kernel_symbols */ | |
1755 | static const struct kernel_symbol *lookup_symbol(const char *name, | |
1756 | const struct kernel_symbol *start, | |
1757 | const struct kernel_symbol *stop) | |
1758 | { | |
1759 | const struct kernel_symbol *ks = start; | |
1760 | for (; ks < stop; ks++) | |
1761 | if (strcmp(ks->name, name) == 0) | |
1762 | return ks; | |
1763 | return NULL; | |
1764 | } | |
1765 | ||
1766 | static int is_exported(const char *name, unsigned long value, | |
1767 | const struct module *mod) | |
1768 | { | |
1769 | const struct kernel_symbol *ks; | |
1770 | if (!mod) | |
1771 | ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab); | |
1772 | else | |
1773 | ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms); | |
1774 | return ks != NULL && ks->value == value; | |
1775 | } | |
1776 | ||
1777 | /* As per nm */ | |
1778 | static char elf_type(const Elf_Sym *sym, | |
1779 | Elf_Shdr *sechdrs, | |
1780 | const char *secstrings, | |
1781 | struct module *mod) | |
1782 | { | |
1783 | if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { | |
1784 | if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) | |
1785 | return 'v'; | |
1786 | else | |
1787 | return 'w'; | |
1788 | } | |
1789 | if (sym->st_shndx == SHN_UNDEF) | |
1790 | return 'U'; | |
1791 | if (sym->st_shndx == SHN_ABS) | |
1792 | return 'a'; | |
1793 | if (sym->st_shndx >= SHN_LORESERVE) | |
1794 | return '?'; | |
1795 | if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) | |
1796 | return 't'; | |
1797 | if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC | |
1798 | && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { | |
1799 | if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) | |
1800 | return 'r'; | |
1801 | else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
1802 | return 'g'; | |
1803 | else | |
1804 | return 'd'; | |
1805 | } | |
1806 | if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { | |
1807 | if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
1808 | return 's'; | |
1809 | else | |
1810 | return 'b'; | |
1811 | } | |
1812 | if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug")) | |
1813 | return 'n'; | |
1814 | return '?'; | |
1815 | } | |
1816 | ||
1817 | static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs, | |
1818 | unsigned int shnum) | |
1819 | { | |
1820 | const Elf_Shdr *sec; | |
1821 | ||
1822 | if (src->st_shndx == SHN_UNDEF | |
1823 | || src->st_shndx >= shnum | |
1824 | || !src->st_name) | |
1825 | return false; | |
1826 | ||
1827 | sec = sechdrs + src->st_shndx; | |
1828 | if (!(sec->sh_flags & SHF_ALLOC) | |
1829 | #ifndef CONFIG_KALLSYMS_ALL | |
1830 | || !(sec->sh_flags & SHF_EXECINSTR) | |
1831 | #endif | |
1832 | || (sec->sh_entsize & INIT_OFFSET_MASK)) | |
1833 | return false; | |
1834 | ||
1835 | return true; | |
1836 | } | |
1837 | ||
1838 | static unsigned long layout_symtab(struct module *mod, | |
1839 | Elf_Shdr *sechdrs, | |
1840 | unsigned int symindex, | |
1841 | unsigned int strindex, | |
1842 | const Elf_Ehdr *hdr, | |
1843 | const char *secstrings, | |
1844 | unsigned long *pstroffs, | |
1845 | unsigned long *strmap) | |
1846 | { | |
1847 | unsigned long symoffs; | |
1848 | Elf_Shdr *symsect = sechdrs + symindex; | |
1849 | Elf_Shdr *strsect = sechdrs + strindex; | |
1850 | const Elf_Sym *src; | |
1851 | const char *strtab; | |
1852 | unsigned int i, nsrc, ndst; | |
1853 | ||
1854 | /* Put symbol section at end of init part of module. */ | |
1855 | symsect->sh_flags |= SHF_ALLOC; | |
1856 | symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect, | |
1857 | symindex) | INIT_OFFSET_MASK; | |
1858 | DEBUGP("\t%s\n", secstrings + symsect->sh_name); | |
1859 | ||
1860 | src = (void *)hdr + symsect->sh_offset; | |
1861 | nsrc = symsect->sh_size / sizeof(*src); | |
1862 | strtab = (void *)hdr + strsect->sh_offset; | |
1863 | for (ndst = i = 1; i < nsrc; ++i, ++src) | |
1864 | if (is_core_symbol(src, sechdrs, hdr->e_shnum)) { | |
1865 | unsigned int j = src->st_name; | |
1866 | ||
1867 | while(!__test_and_set_bit(j, strmap) && strtab[j]) | |
1868 | ++j; | |
1869 | ++ndst; | |
1870 | } | |
1871 | ||
1872 | /* Append room for core symbols at end of core part. */ | |
1873 | symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1); | |
1874 | mod->core_size = symoffs + ndst * sizeof(Elf_Sym); | |
1875 | ||
1876 | /* Put string table section at end of init part of module. */ | |
1877 | strsect->sh_flags |= SHF_ALLOC; | |
1878 | strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect, | |
1879 | strindex) | INIT_OFFSET_MASK; | |
1880 | DEBUGP("\t%s\n", secstrings + strsect->sh_name); | |
1881 | ||
1882 | /* Append room for core symbols' strings at end of core part. */ | |
1883 | *pstroffs = mod->core_size; | |
1884 | __set_bit(0, strmap); | |
1885 | mod->core_size += bitmap_weight(strmap, strsect->sh_size); | |
1886 | ||
1887 | return symoffs; | |
1888 | } | |
1889 | ||
1890 | static void add_kallsyms(struct module *mod, | |
1891 | Elf_Shdr *sechdrs, | |
1892 | unsigned int shnum, | |
1893 | unsigned int symindex, | |
1894 | unsigned int strindex, | |
1895 | unsigned long symoffs, | |
1896 | unsigned long stroffs, | |
1897 | const char *secstrings, | |
1898 | unsigned long *strmap) | |
1899 | { | |
1900 | unsigned int i, ndst; | |
1901 | const Elf_Sym *src; | |
1902 | Elf_Sym *dst; | |
1903 | char *s; | |
1904 | ||
1905 | mod->symtab = (void *)sechdrs[symindex].sh_addr; | |
1906 | mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym); | |
1907 | mod->strtab = (void *)sechdrs[strindex].sh_addr; | |
1908 | ||
1909 | /* Set types up while we still have access to sections. */ | |
1910 | for (i = 0; i < mod->num_symtab; i++) | |
1911 | mod->symtab[i].st_info | |
1912 | = elf_type(&mod->symtab[i], sechdrs, secstrings, mod); | |
1913 | ||
1914 | mod->core_symtab = dst = mod->module_core + symoffs; | |
1915 | src = mod->symtab; | |
1916 | *dst = *src; | |
1917 | for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) { | |
1918 | if (!is_core_symbol(src, sechdrs, shnum)) | |
1919 | continue; | |
1920 | dst[ndst] = *src; | |
1921 | dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name); | |
1922 | ++ndst; | |
1923 | } | |
1924 | mod->core_num_syms = ndst; | |
1925 | ||
1926 | mod->core_strtab = s = mod->module_core + stroffs; | |
1927 | for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i) | |
1928 | if (test_bit(i, strmap)) | |
1929 | *++s = mod->strtab[i]; | |
1930 | } | |
1931 | #else | |
1932 | static inline unsigned long layout_symtab(struct module *mod, | |
1933 | Elf_Shdr *sechdrs, | |
1934 | unsigned int symindex, | |
1935 | unsigned int strindex, | |
1936 | const Elf_Ehdr *hdr, | |
1937 | const char *secstrings, | |
1938 | unsigned long *pstroffs, | |
1939 | unsigned long *strmap) | |
1940 | { | |
1941 | return 0; | |
1942 | } | |
1943 | ||
1944 | static inline void add_kallsyms(struct module *mod, | |
1945 | Elf_Shdr *sechdrs, | |
1946 | unsigned int shnum, | |
1947 | unsigned int symindex, | |
1948 | unsigned int strindex, | |
1949 | unsigned long symoffs, | |
1950 | unsigned long stroffs, | |
1951 | const char *secstrings, | |
1952 | const unsigned long *strmap) | |
1953 | { | |
1954 | } | |
1955 | #endif /* CONFIG_KALLSYMS */ | |
1956 | ||
1957 | static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num) | |
1958 | { | |
1959 | #ifdef CONFIG_DYNAMIC_DEBUG | |
1960 | if (ddebug_add_module(debug, num, debug->modname)) | |
1961 | printk(KERN_ERR "dynamic debug error adding module: %s\n", | |
1962 | debug->modname); | |
1963 | #endif | |
1964 | } | |
1965 | ||
1966 | static void *module_alloc_update_bounds(unsigned long size) | |
1967 | { | |
1968 | void *ret = module_alloc(size); | |
1969 | ||
1970 | if (ret) { | |
1971 | /* Update module bounds. */ | |
1972 | if ((unsigned long)ret < module_addr_min) | |
1973 | module_addr_min = (unsigned long)ret; | |
1974 | if ((unsigned long)ret + size > module_addr_max) | |
1975 | module_addr_max = (unsigned long)ret + size; | |
1976 | } | |
1977 | return ret; | |
1978 | } | |
1979 | ||
1980 | #ifdef CONFIG_DEBUG_KMEMLEAK | |
1981 | static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr, | |
1982 | Elf_Shdr *sechdrs, char *secstrings) | |
1983 | { | |
1984 | unsigned int i; | |
1985 | ||
1986 | /* only scan the sections containing data */ | |
1987 | kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL); | |
1988 | ||
1989 | for (i = 1; i < hdr->e_shnum; i++) { | |
1990 | if (!(sechdrs[i].sh_flags & SHF_ALLOC)) | |
1991 | continue; | |
1992 | if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0 | |
1993 | && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0) | |
1994 | continue; | |
1995 | ||
1996 | kmemleak_scan_area((void *)sechdrs[i].sh_addr, | |
1997 | sechdrs[i].sh_size, GFP_KERNEL); | |
1998 | } | |
1999 | } | |
2000 | #else | |
2001 | static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr, | |
2002 | Elf_Shdr *sechdrs, char *secstrings) | |
2003 | { | |
2004 | } | |
2005 | #endif | |
2006 | ||
2007 | /* Allocate and load the module: note that size of section 0 is always | |
2008 | zero, and we rely on this for optional sections. */ | |
2009 | static noinline struct module *load_module(void __user *umod, | |
2010 | unsigned long len, | |
2011 | const char __user *uargs) | |
2012 | { | |
2013 | Elf_Ehdr *hdr; | |
2014 | Elf_Shdr *sechdrs; | |
2015 | char *secstrings, *args, *modmagic, *strtab = NULL; | |
2016 | char *staging; | |
2017 | unsigned int i; | |
2018 | unsigned int symindex = 0; | |
2019 | unsigned int strindex = 0; | |
2020 | unsigned int modindex, versindex, infoindex, pcpuindex; | |
2021 | struct module *mod; | |
2022 | long err = 0; | |
2023 | void *ptr = NULL; /* Stops spurious gcc warning */ | |
2024 | unsigned long symoffs, stroffs, *strmap; | |
2025 | void __percpu *percpu; | |
2026 | ||
2027 | mm_segment_t old_fs; | |
2028 | ||
2029 | DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n", | |
2030 | umod, len, uargs); | |
2031 | if (len < sizeof(*hdr)) | |
2032 | return ERR_PTR(-ENOEXEC); | |
2033 | ||
2034 | /* Suck in entire file: we'll want most of it. */ | |
2035 | /* vmalloc barfs on "unusual" numbers. Check here */ | |
2036 | if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL) | |
2037 | return ERR_PTR(-ENOMEM); | |
2038 | ||
2039 | if (copy_from_user(hdr, umod, len) != 0) { | |
2040 | err = -EFAULT; | |
2041 | goto free_hdr; | |
2042 | } | |
2043 | ||
2044 | /* Sanity checks against insmoding binaries or wrong arch, | |
2045 | weird elf version */ | |
2046 | if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0 | |
2047 | || hdr->e_type != ET_REL | |
2048 | || !elf_check_arch(hdr) | |
2049 | || hdr->e_shentsize != sizeof(*sechdrs)) { | |
2050 | err = -ENOEXEC; | |
2051 | goto free_hdr; | |
2052 | } | |
2053 | ||
2054 | if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) | |
2055 | goto truncated; | |
2056 | ||
2057 | /* Convenience variables */ | |
2058 | sechdrs = (void *)hdr + hdr->e_shoff; | |
2059 | secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; | |
2060 | sechdrs[0].sh_addr = 0; | |
2061 | ||
2062 | for (i = 1; i < hdr->e_shnum; i++) { | |
2063 | if (sechdrs[i].sh_type != SHT_NOBITS | |
2064 | && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) | |
2065 | goto truncated; | |
2066 | ||
2067 | /* Mark all sections sh_addr with their address in the | |
2068 | temporary image. */ | |
2069 | sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset; | |
2070 | ||
2071 | /* Internal symbols and strings. */ | |
2072 | if (sechdrs[i].sh_type == SHT_SYMTAB) { | |
2073 | symindex = i; | |
2074 | strindex = sechdrs[i].sh_link; | |
2075 | strtab = (char *)hdr + sechdrs[strindex].sh_offset; | |
2076 | } | |
2077 | #ifndef CONFIG_MODULE_UNLOAD | |
2078 | /* Don't load .exit sections */ | |
2079 | if (strstarts(secstrings+sechdrs[i].sh_name, ".exit")) | |
2080 | sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
2081 | #endif | |
2082 | } | |
2083 | ||
2084 | modindex = find_sec(hdr, sechdrs, secstrings, | |
2085 | ".gnu.linkonce.this_module"); | |
2086 | if (!modindex) { | |
2087 | printk(KERN_WARNING "No module found in object\n"); | |
2088 | err = -ENOEXEC; | |
2089 | goto free_hdr; | |
2090 | } | |
2091 | /* This is temporary: point mod into copy of data. */ | |
2092 | mod = (void *)sechdrs[modindex].sh_addr; | |
2093 | ||
2094 | if (symindex == 0) { | |
2095 | printk(KERN_WARNING "%s: module has no symbols (stripped?)\n", | |
2096 | mod->name); | |
2097 | err = -ENOEXEC; | |
2098 | goto free_hdr; | |
2099 | } | |
2100 | ||
2101 | versindex = find_sec(hdr, sechdrs, secstrings, "__versions"); | |
2102 | infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo"); | |
2103 | pcpuindex = find_pcpusec(hdr, sechdrs, secstrings); | |
2104 | ||
2105 | /* Don't keep modinfo and version sections. */ | |
2106 | sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
2107 | sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
2108 | ||
2109 | /* Check module struct version now, before we try to use module. */ | |
2110 | if (!check_modstruct_version(sechdrs, versindex, mod)) { | |
2111 | err = -ENOEXEC; | |
2112 | goto free_hdr; | |
2113 | } | |
2114 | ||
2115 | modmagic = get_modinfo(sechdrs, infoindex, "vermagic"); | |
2116 | /* This is allowed: modprobe --force will invalidate it. */ | |
2117 | if (!modmagic) { | |
2118 | err = try_to_force_load(mod, "bad vermagic"); | |
2119 | if (err) | |
2120 | goto free_hdr; | |
2121 | } else if (!same_magic(modmagic, vermagic, versindex)) { | |
2122 | printk(KERN_ERR "%s: version magic '%s' should be '%s'\n", | |
2123 | mod->name, modmagic, vermagic); | |
2124 | err = -ENOEXEC; | |
2125 | goto free_hdr; | |
2126 | } | |
2127 | ||
2128 | staging = get_modinfo(sechdrs, infoindex, "staging"); | |
2129 | if (staging) { | |
2130 | add_taint_module(mod, TAINT_CRAP); | |
2131 | printk(KERN_WARNING "%s: module is from the staging directory," | |
2132 | " the quality is unknown, you have been warned.\n", | |
2133 | mod->name); | |
2134 | } | |
2135 | ||
2136 | /* Now copy in args */ | |
2137 | args = strndup_user(uargs, ~0UL >> 1); | |
2138 | if (IS_ERR(args)) { | |
2139 | err = PTR_ERR(args); | |
2140 | goto free_hdr; | |
2141 | } | |
2142 | ||
2143 | strmap = kzalloc(BITS_TO_LONGS(sechdrs[strindex].sh_size) | |
2144 | * sizeof(long), GFP_KERNEL); | |
2145 | if (!strmap) { | |
2146 | err = -ENOMEM; | |
2147 | goto free_mod; | |
2148 | } | |
2149 | ||
2150 | if (find_module(mod->name)) { | |
2151 | err = -EEXIST; | |
2152 | goto free_mod; | |
2153 | } | |
2154 | ||
2155 | mod->state = MODULE_STATE_COMING; | |
2156 | ||
2157 | /* Allow arches to frob section contents and sizes. */ | |
2158 | err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod); | |
2159 | if (err < 0) | |
2160 | goto free_mod; | |
2161 | ||
2162 | if (pcpuindex) { | |
2163 | /* We have a special allocation for this section. */ | |
2164 | err = percpu_modalloc(mod, sechdrs[pcpuindex].sh_size, | |
2165 | sechdrs[pcpuindex].sh_addralign); | |
2166 | if (err) | |
2167 | goto free_mod; | |
2168 | sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
2169 | } | |
2170 | /* Keep this around for failure path. */ | |
2171 | percpu = mod_percpu(mod); | |
2172 | ||
2173 | /* Determine total sizes, and put offsets in sh_entsize. For now | |
2174 | this is done generically; there doesn't appear to be any | |
2175 | special cases for the architectures. */ | |
2176 | layout_sections(mod, hdr, sechdrs, secstrings); | |
2177 | symoffs = layout_symtab(mod, sechdrs, symindex, strindex, hdr, | |
2178 | secstrings, &stroffs, strmap); | |
2179 | ||
2180 | /* Do the allocs. */ | |
2181 | ptr = module_alloc_update_bounds(mod->core_size); | |
2182 | /* | |
2183 | * The pointer to this block is stored in the module structure | |
2184 | * which is inside the block. Just mark it as not being a | |
2185 | * leak. | |
2186 | */ | |
2187 | kmemleak_not_leak(ptr); | |
2188 | if (!ptr) { | |
2189 | err = -ENOMEM; | |
2190 | goto free_percpu; | |
2191 | } | |
2192 | memset(ptr, 0, mod->core_size); | |
2193 | mod->module_core = ptr; | |
2194 | ||
2195 | ptr = module_alloc_update_bounds(mod->init_size); | |
2196 | /* | |
2197 | * The pointer to this block is stored in the module structure | |
2198 | * which is inside the block. This block doesn't need to be | |
2199 | * scanned as it contains data and code that will be freed | |
2200 | * after the module is initialized. | |
2201 | */ | |
2202 | kmemleak_ignore(ptr); | |
2203 | if (!ptr && mod->init_size) { | |
2204 | err = -ENOMEM; | |
2205 | goto free_core; | |
2206 | } | |
2207 | memset(ptr, 0, mod->init_size); | |
2208 | mod->module_init = ptr; | |
2209 | ||
2210 | /* Transfer each section which specifies SHF_ALLOC */ | |
2211 | DEBUGP("final section addresses:\n"); | |
2212 | for (i = 0; i < hdr->e_shnum; i++) { | |
2213 | void *dest; | |
2214 | ||
2215 | if (!(sechdrs[i].sh_flags & SHF_ALLOC)) | |
2216 | continue; | |
2217 | ||
2218 | if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK) | |
2219 | dest = mod->module_init | |
2220 | + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK); | |
2221 | else | |
2222 | dest = mod->module_core + sechdrs[i].sh_entsize; | |
2223 | ||
2224 | if (sechdrs[i].sh_type != SHT_NOBITS) | |
2225 | memcpy(dest, (void *)sechdrs[i].sh_addr, | |
2226 | sechdrs[i].sh_size); | |
2227 | /* Update sh_addr to point to copy in image. */ | |
2228 | sechdrs[i].sh_addr = (unsigned long)dest; | |
2229 | DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name); | |
2230 | } | |
2231 | /* Module has been moved. */ | |
2232 | mod = (void *)sechdrs[modindex].sh_addr; | |
2233 | kmemleak_load_module(mod, hdr, sechdrs, secstrings); | |
2234 | ||
2235 | #if defined(CONFIG_MODULE_UNLOAD) | |
2236 | mod->refptr = alloc_percpu(struct module_ref); | |
2237 | if (!mod->refptr) { | |
2238 | err = -ENOMEM; | |
2239 | goto free_init; | |
2240 | } | |
2241 | #endif | |
2242 | /* Now we've moved module, initialize linked lists, etc. */ | |
2243 | module_unload_init(mod); | |
2244 | ||
2245 | /* add kobject, so we can reference it. */ | |
2246 | err = mod_sysfs_init(mod); | |
2247 | if (err) | |
2248 | goto free_unload; | |
2249 | ||
2250 | /* Set up license info based on the info section */ | |
2251 | set_license(mod, get_modinfo(sechdrs, infoindex, "license")); | |
2252 | ||
2253 | /* | |
2254 | * ndiswrapper is under GPL by itself, but loads proprietary modules. | |
2255 | * Don't use add_taint_module(), as it would prevent ndiswrapper from | |
2256 | * using GPL-only symbols it needs. | |
2257 | */ | |
2258 | if (strcmp(mod->name, "ndiswrapper") == 0) | |
2259 | add_taint(TAINT_PROPRIETARY_MODULE); | |
2260 | ||
2261 | /* driverloader was caught wrongly pretending to be under GPL */ | |
2262 | if (strcmp(mod->name, "driverloader") == 0) | |
2263 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE); | |
2264 | ||
2265 | /* Set up MODINFO_ATTR fields */ | |
2266 | setup_modinfo(mod, sechdrs, infoindex); | |
2267 | ||
2268 | /* Fix up syms, so that st_value is a pointer to location. */ | |
2269 | err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex, | |
2270 | mod); | |
2271 | if (err < 0) | |
2272 | goto cleanup; | |
2273 | ||
2274 | /* Now we've got everything in the final locations, we can | |
2275 | * find optional sections. */ | |
2276 | mod->kp = section_objs(hdr, sechdrs, secstrings, "__param", | |
2277 | sizeof(*mod->kp), &mod->num_kp); | |
2278 | mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab", | |
2279 | sizeof(*mod->syms), &mod->num_syms); | |
2280 | mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab"); | |
2281 | mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl", | |
2282 | sizeof(*mod->gpl_syms), | |
2283 | &mod->num_gpl_syms); | |
2284 | mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl"); | |
2285 | mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings, | |
2286 | "__ksymtab_gpl_future", | |
2287 | sizeof(*mod->gpl_future_syms), | |
2288 | &mod->num_gpl_future_syms); | |
2289 | mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings, | |
2290 | "__kcrctab_gpl_future"); | |
2291 | ||
2292 | #ifdef CONFIG_UNUSED_SYMBOLS | |
2293 | mod->unused_syms = section_objs(hdr, sechdrs, secstrings, | |
2294 | "__ksymtab_unused", | |
2295 | sizeof(*mod->unused_syms), | |
2296 | &mod->num_unused_syms); | |
2297 | mod->unused_crcs = section_addr(hdr, sechdrs, secstrings, | |
2298 | "__kcrctab_unused"); | |
2299 | mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings, | |
2300 | "__ksymtab_unused_gpl", | |
2301 | sizeof(*mod->unused_gpl_syms), | |
2302 | &mod->num_unused_gpl_syms); | |
2303 | mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings, | |
2304 | "__kcrctab_unused_gpl"); | |
2305 | #endif | |
2306 | #ifdef CONFIG_CONSTRUCTORS | |
2307 | mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors", | |
2308 | sizeof(*mod->ctors), &mod->num_ctors); | |
2309 | #endif | |
2310 | ||
2311 | #ifdef CONFIG_TRACEPOINTS | |
2312 | mod->tracepoints = section_objs(hdr, sechdrs, secstrings, | |
2313 | "__tracepoints", | |
2314 | sizeof(*mod->tracepoints), | |
2315 | &mod->num_tracepoints); | |
2316 | #endif | |
2317 | #ifdef CONFIG_EVENT_TRACING | |
2318 | mod->trace_events = section_objs(hdr, sechdrs, secstrings, | |
2319 | "_ftrace_events", | |
2320 | sizeof(*mod->trace_events), | |
2321 | &mod->num_trace_events); | |
2322 | /* | |
2323 | * This section contains pointers to allocated objects in the trace | |
2324 | * code and not scanning it leads to false positives. | |
2325 | */ | |
2326 | kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) * | |
2327 | mod->num_trace_events, GFP_KERNEL); | |
2328 | #endif | |
2329 | #ifdef CONFIG_FTRACE_MCOUNT_RECORD | |
2330 | /* sechdrs[0].sh_size is always zero */ | |
2331 | mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings, | |
2332 | "__mcount_loc", | |
2333 | sizeof(*mod->ftrace_callsites), | |
2334 | &mod->num_ftrace_callsites); | |
2335 | #endif | |
2336 | #ifdef CONFIG_MODVERSIONS | |
2337 | if ((mod->num_syms && !mod->crcs) | |
2338 | || (mod->num_gpl_syms && !mod->gpl_crcs) | |
2339 | || (mod->num_gpl_future_syms && !mod->gpl_future_crcs) | |
2340 | #ifdef CONFIG_UNUSED_SYMBOLS | |
2341 | || (mod->num_unused_syms && !mod->unused_crcs) | |
2342 | || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs) | |
2343 | #endif | |
2344 | ) { | |
2345 | err = try_to_force_load(mod, | |
2346 | "no versions for exported symbols"); | |
2347 | if (err) | |
2348 | goto cleanup; | |
2349 | } | |
2350 | #endif | |
2351 | ||
2352 | /* Now do relocations. */ | |
2353 | for (i = 1; i < hdr->e_shnum; i++) { | |
2354 | const char *strtab = (char *)sechdrs[strindex].sh_addr; | |
2355 | unsigned int info = sechdrs[i].sh_info; | |
2356 | ||
2357 | /* Not a valid relocation section? */ | |
2358 | if (info >= hdr->e_shnum) | |
2359 | continue; | |
2360 | ||
2361 | /* Don't bother with non-allocated sections */ | |
2362 | if (!(sechdrs[info].sh_flags & SHF_ALLOC)) | |
2363 | continue; | |
2364 | ||
2365 | if (sechdrs[i].sh_type == SHT_REL) | |
2366 | err = apply_relocate(sechdrs, strtab, symindex, i,mod); | |
2367 | else if (sechdrs[i].sh_type == SHT_RELA) | |
2368 | err = apply_relocate_add(sechdrs, strtab, symindex, i, | |
2369 | mod); | |
2370 | if (err < 0) | |
2371 | goto cleanup; | |
2372 | } | |
2373 | ||
2374 | /* Find duplicate symbols */ | |
2375 | err = verify_export_symbols(mod); | |
2376 | if (err < 0) | |
2377 | goto cleanup; | |
2378 | ||
2379 | /* Set up and sort exception table */ | |
2380 | mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table", | |
2381 | sizeof(*mod->extable), &mod->num_exentries); | |
2382 | sort_extable(mod->extable, mod->extable + mod->num_exentries); | |
2383 | ||
2384 | /* Finally, copy percpu area over. */ | |
2385 | percpu_modcopy(mod, (void *)sechdrs[pcpuindex].sh_addr, | |
2386 | sechdrs[pcpuindex].sh_size); | |
2387 | ||
2388 | add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex, | |
2389 | symoffs, stroffs, secstrings, strmap); | |
2390 | kfree(strmap); | |
2391 | strmap = NULL; | |
2392 | ||
2393 | if (!mod->taints) { | |
2394 | struct _ddebug *debug; | |
2395 | unsigned int num_debug; | |
2396 | ||
2397 | debug = section_objs(hdr, sechdrs, secstrings, "__verbose", | |
2398 | sizeof(*debug), &num_debug); | |
2399 | if (debug) | |
2400 | dynamic_debug_setup(debug, num_debug); | |
2401 | } | |
2402 | ||
2403 | err = module_finalize(hdr, sechdrs, mod); | |
2404 | if (err < 0) | |
2405 | goto cleanup; | |
2406 | ||
2407 | /* flush the icache in correct context */ | |
2408 | old_fs = get_fs(); | |
2409 | set_fs(KERNEL_DS); | |
2410 | ||
2411 | /* | |
2412 | * Flush the instruction cache, since we've played with text. | |
2413 | * Do it before processing of module parameters, so the module | |
2414 | * can provide parameter accessor functions of its own. | |
2415 | */ | |
2416 | if (mod->module_init) | |
2417 | flush_icache_range((unsigned long)mod->module_init, | |
2418 | (unsigned long)mod->module_init | |
2419 | + mod->init_size); | |
2420 | flush_icache_range((unsigned long)mod->module_core, | |
2421 | (unsigned long)mod->module_core + mod->core_size); | |
2422 | ||
2423 | set_fs(old_fs); | |
2424 | ||
2425 | mod->args = args; | |
2426 | if (section_addr(hdr, sechdrs, secstrings, "__obsparm")) | |
2427 | printk(KERN_WARNING "%s: Ignoring obsolete parameters\n", | |
2428 | mod->name); | |
2429 | ||
2430 | /* Now sew it into the lists so we can get lockdep and oops | |
2431 | * info during argument parsing. Noone should access us, since | |
2432 | * strong_try_module_get() will fail. | |
2433 | * lockdep/oops can run asynchronous, so use the RCU list insertion | |
2434 | * function to insert in a way safe to concurrent readers. | |
2435 | * The mutex protects against concurrent writers. | |
2436 | */ | |
2437 | list_add_rcu(&mod->list, &modules); | |
2438 | ||
2439 | err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL); | |
2440 | if (err < 0) | |
2441 | goto unlink; | |
2442 | ||
2443 | err = mod_sysfs_setup(mod, mod->kp, mod->num_kp); | |
2444 | if (err < 0) | |
2445 | goto unlink; | |
2446 | add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs); | |
2447 | add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs); | |
2448 | ||
2449 | /* Get rid of temporary copy */ | |
2450 | vfree(hdr); | |
2451 | ||
2452 | trace_module_load(mod); | |
2453 | ||
2454 | /* Done! */ | |
2455 | return mod; | |
2456 | ||
2457 | unlink: | |
2458 | /* Unlink carefully: kallsyms could be walking list. */ | |
2459 | list_del_rcu(&mod->list); | |
2460 | synchronize_sched(); | |
2461 | module_arch_cleanup(mod); | |
2462 | cleanup: | |
2463 | free_modinfo(mod); | |
2464 | kobject_del(&mod->mkobj.kobj); | |
2465 | kobject_put(&mod->mkobj.kobj); | |
2466 | free_unload: | |
2467 | module_unload_free(mod); | |
2468 | #if defined(CONFIG_MODULE_UNLOAD) | |
2469 | free_percpu(mod->refptr); | |
2470 | free_init: | |
2471 | #endif | |
2472 | module_free(mod, mod->module_init); | |
2473 | free_core: | |
2474 | module_free(mod, mod->module_core); | |
2475 | /* mod will be freed with core. Don't access it beyond this line! */ | |
2476 | free_percpu: | |
2477 | free_percpu(percpu); | |
2478 | free_mod: | |
2479 | kfree(args); | |
2480 | kfree(strmap); | |
2481 | free_hdr: | |
2482 | vfree(hdr); | |
2483 | return ERR_PTR(err); | |
2484 | ||
2485 | truncated: | |
2486 | printk(KERN_ERR "Module len %lu truncated\n", len); | |
2487 | err = -ENOEXEC; | |
2488 | goto free_hdr; | |
2489 | } | |
2490 | ||
2491 | /* Call module constructors. */ | |
2492 | static void do_mod_ctors(struct module *mod) | |
2493 | { | |
2494 | #ifdef CONFIG_CONSTRUCTORS | |
2495 | unsigned long i; | |
2496 | ||
2497 | for (i = 0; i < mod->num_ctors; i++) | |
2498 | mod->ctors[i](); | |
2499 | #endif | |
2500 | } | |
2501 | ||
2502 | /* This is where the real work happens */ | |
2503 | SYSCALL_DEFINE3(init_module, void __user *, umod, | |
2504 | unsigned long, len, const char __user *, uargs) | |
2505 | { | |
2506 | struct module *mod; | |
2507 | int ret = 0; | |
2508 | ||
2509 | /* Must have permission */ | |
2510 | if (!capable(CAP_SYS_MODULE) || modules_disabled) | |
2511 | return -EPERM; | |
2512 | ||
2513 | /* Only one module load at a time, please */ | |
2514 | if (mutex_lock_interruptible(&module_mutex) != 0) | |
2515 | return -EINTR; | |
2516 | ||
2517 | /* Do all the hard work */ | |
2518 | mod = load_module(umod, len, uargs); | |
2519 | if (IS_ERR(mod)) { | |
2520 | mutex_unlock(&module_mutex); | |
2521 | return PTR_ERR(mod); | |
2522 | } | |
2523 | ||
2524 | /* Drop lock so they can recurse */ | |
2525 | mutex_unlock(&module_mutex); | |
2526 | ||
2527 | blocking_notifier_call_chain(&module_notify_list, | |
2528 | MODULE_STATE_COMING, mod); | |
2529 | ||
2530 | do_mod_ctors(mod); | |
2531 | /* Start the module */ | |
2532 | if (mod->init != NULL) | |
2533 | ret = do_one_initcall(mod->init); | |
2534 | if (ret < 0) { | |
2535 | /* Init routine failed: abort. Try to protect us from | |
2536 | buggy refcounters. */ | |
2537 | mod->state = MODULE_STATE_GOING; | |
2538 | synchronize_sched(); | |
2539 | module_put(mod); | |
2540 | blocking_notifier_call_chain(&module_notify_list, | |
2541 | MODULE_STATE_GOING, mod); | |
2542 | mutex_lock(&module_mutex); | |
2543 | free_module(mod); | |
2544 | mutex_unlock(&module_mutex); | |
2545 | wake_up(&module_wq); | |
2546 | return ret; | |
2547 | } | |
2548 | if (ret > 0) { | |
2549 | printk(KERN_WARNING | |
2550 | "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n" | |
2551 | "%s: loading module anyway...\n", | |
2552 | __func__, mod->name, ret, | |
2553 | __func__); | |
2554 | dump_stack(); | |
2555 | } | |
2556 | ||
2557 | /* Now it's a first class citizen! Wake up anyone waiting for it. */ | |
2558 | mod->state = MODULE_STATE_LIVE; | |
2559 | wake_up(&module_wq); | |
2560 | blocking_notifier_call_chain(&module_notify_list, | |
2561 | MODULE_STATE_LIVE, mod); | |
2562 | ||
2563 | /* We need to finish all async code before the module init sequence is done */ | |
2564 | async_synchronize_full(); | |
2565 | ||
2566 | mutex_lock(&module_mutex); | |
2567 | /* Drop initial reference. */ | |
2568 | module_put(mod); | |
2569 | trim_init_extable(mod); | |
2570 | #ifdef CONFIG_KALLSYMS | |
2571 | mod->num_symtab = mod->core_num_syms; | |
2572 | mod->symtab = mod->core_symtab; | |
2573 | mod->strtab = mod->core_strtab; | |
2574 | #endif | |
2575 | module_free(mod, mod->module_init); | |
2576 | mod->module_init = NULL; | |
2577 | mod->init_size = 0; | |
2578 | mod->init_text_size = 0; | |
2579 | mutex_unlock(&module_mutex); | |
2580 | ||
2581 | return 0; | |
2582 | } | |
2583 | ||
2584 | static inline int within(unsigned long addr, void *start, unsigned long size) | |
2585 | { | |
2586 | return ((void *)addr >= start && (void *)addr < start + size); | |
2587 | } | |
2588 | ||
2589 | #ifdef CONFIG_KALLSYMS | |
2590 | /* | |
2591 | * This ignores the intensely annoying "mapping symbols" found | |
2592 | * in ARM ELF files: $a, $t and $d. | |
2593 | */ | |
2594 | static inline int is_arm_mapping_symbol(const char *str) | |
2595 | { | |
2596 | return str[0] == '$' && strchr("atd", str[1]) | |
2597 | && (str[2] == '\0' || str[2] == '.'); | |
2598 | } | |
2599 | ||
2600 | static const char *get_ksymbol(struct module *mod, | |
2601 | unsigned long addr, | |
2602 | unsigned long *size, | |
2603 | unsigned long *offset) | |
2604 | { | |
2605 | unsigned int i, best = 0; | |
2606 | unsigned long nextval; | |
2607 | ||
2608 | /* At worse, next value is at end of module */ | |
2609 | if (within_module_init(addr, mod)) | |
2610 | nextval = (unsigned long)mod->module_init+mod->init_text_size; | |
2611 | else | |
2612 | nextval = (unsigned long)mod->module_core+mod->core_text_size; | |
2613 | ||
2614 | /* Scan for closest preceeding symbol, and next symbol. (ELF | |
2615 | starts real symbols at 1). */ | |
2616 | for (i = 1; i < mod->num_symtab; i++) { | |
2617 | if (mod->symtab[i].st_shndx == SHN_UNDEF) | |
2618 | continue; | |
2619 | ||
2620 | /* We ignore unnamed symbols: they're uninformative | |
2621 | * and inserted at a whim. */ | |
2622 | if (mod->symtab[i].st_value <= addr | |
2623 | && mod->symtab[i].st_value > mod->symtab[best].st_value | |
2624 | && *(mod->strtab + mod->symtab[i].st_name) != '\0' | |
2625 | && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name)) | |
2626 | best = i; | |
2627 | if (mod->symtab[i].st_value > addr | |
2628 | && mod->symtab[i].st_value < nextval | |
2629 | && *(mod->strtab + mod->symtab[i].st_name) != '\0' | |
2630 | && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name)) | |
2631 | nextval = mod->symtab[i].st_value; | |
2632 | } | |
2633 | ||
2634 | if (!best) | |
2635 | return NULL; | |
2636 | ||
2637 | if (size) | |
2638 | *size = nextval - mod->symtab[best].st_value; | |
2639 | if (offset) | |
2640 | *offset = addr - mod->symtab[best].st_value; | |
2641 | return mod->strtab + mod->symtab[best].st_name; | |
2642 | } | |
2643 | ||
2644 | /* For kallsyms to ask for address resolution. NULL means not found. Careful | |
2645 | * not to lock to avoid deadlock on oopses, simply disable preemption. */ | |
2646 | const char *module_address_lookup(unsigned long addr, | |
2647 | unsigned long *size, | |
2648 | unsigned long *offset, | |
2649 | char **modname, | |
2650 | char *namebuf) | |
2651 | { | |
2652 | struct module *mod; | |
2653 | const char *ret = NULL; | |
2654 | ||
2655 | preempt_disable(); | |
2656 | list_for_each_entry_rcu(mod, &modules, list) { | |
2657 | if (within_module_init(addr, mod) || | |
2658 | within_module_core(addr, mod)) { | |
2659 | if (modname) | |
2660 | *modname = mod->name; | |
2661 | ret = get_ksymbol(mod, addr, size, offset); | |
2662 | break; | |
2663 | } | |
2664 | } | |
2665 | /* Make a copy in here where it's safe */ | |
2666 | if (ret) { | |
2667 | strncpy(namebuf, ret, KSYM_NAME_LEN - 1); | |
2668 | ret = namebuf; | |
2669 | } | |
2670 | preempt_enable(); | |
2671 | return ret; | |
2672 | } | |
2673 | ||
2674 | int lookup_module_symbol_name(unsigned long addr, char *symname) | |
2675 | { | |
2676 | struct module *mod; | |
2677 | ||
2678 | preempt_disable(); | |
2679 | list_for_each_entry_rcu(mod, &modules, list) { | |
2680 | if (within_module_init(addr, mod) || | |
2681 | within_module_core(addr, mod)) { | |
2682 | const char *sym; | |
2683 | ||
2684 | sym = get_ksymbol(mod, addr, NULL, NULL); | |
2685 | if (!sym) | |
2686 | goto out; | |
2687 | strlcpy(symname, sym, KSYM_NAME_LEN); | |
2688 | preempt_enable(); | |
2689 | return 0; | |
2690 | } | |
2691 | } | |
2692 | out: | |
2693 | preempt_enable(); | |
2694 | return -ERANGE; | |
2695 | } | |
2696 | ||
2697 | int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, | |
2698 | unsigned long *offset, char *modname, char *name) | |
2699 | { | |
2700 | struct module *mod; | |
2701 | ||
2702 | preempt_disable(); | |
2703 | list_for_each_entry_rcu(mod, &modules, list) { | |
2704 | if (within_module_init(addr, mod) || | |
2705 | within_module_core(addr, mod)) { | |
2706 | const char *sym; | |
2707 | ||
2708 | sym = get_ksymbol(mod, addr, size, offset); | |
2709 | if (!sym) | |
2710 | goto out; | |
2711 | if (modname) | |
2712 | strlcpy(modname, mod->name, MODULE_NAME_LEN); | |
2713 | if (name) | |
2714 | strlcpy(name, sym, KSYM_NAME_LEN); | |
2715 | preempt_enable(); | |
2716 | return 0; | |
2717 | } | |
2718 | } | |
2719 | out: | |
2720 | preempt_enable(); | |
2721 | return -ERANGE; | |
2722 | } | |
2723 | ||
2724 | int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, | |
2725 | char *name, char *module_name, int *exported) | |
2726 | { | |
2727 | struct module *mod; | |
2728 | ||
2729 | preempt_disable(); | |
2730 | list_for_each_entry_rcu(mod, &modules, list) { | |
2731 | if (symnum < mod->num_symtab) { | |
2732 | *value = mod->symtab[symnum].st_value; | |
2733 | *type = mod->symtab[symnum].st_info; | |
2734 | strlcpy(name, mod->strtab + mod->symtab[symnum].st_name, | |
2735 | KSYM_NAME_LEN); | |
2736 | strlcpy(module_name, mod->name, MODULE_NAME_LEN); | |
2737 | *exported = is_exported(name, *value, mod); | |
2738 | preempt_enable(); | |
2739 | return 0; | |
2740 | } | |
2741 | symnum -= mod->num_symtab; | |
2742 | } | |
2743 | preempt_enable(); | |
2744 | return -ERANGE; | |
2745 | } | |
2746 | ||
2747 | static unsigned long mod_find_symname(struct module *mod, const char *name) | |
2748 | { | |
2749 | unsigned int i; | |
2750 | ||
2751 | for (i = 0; i < mod->num_symtab; i++) | |
2752 | if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 && | |
2753 | mod->symtab[i].st_info != 'U') | |
2754 | return mod->symtab[i].st_value; | |
2755 | return 0; | |
2756 | } | |
2757 | ||
2758 | /* Look for this name: can be of form module:name. */ | |
2759 | unsigned long module_kallsyms_lookup_name(const char *name) | |
2760 | { | |
2761 | struct module *mod; | |
2762 | char *colon; | |
2763 | unsigned long ret = 0; | |
2764 | ||
2765 | /* Don't lock: we're in enough trouble already. */ | |
2766 | preempt_disable(); | |
2767 | if ((colon = strchr(name, ':')) != NULL) { | |
2768 | *colon = '\0'; | |
2769 | if ((mod = find_module(name)) != NULL) | |
2770 | ret = mod_find_symname(mod, colon+1); | |
2771 | *colon = ':'; | |
2772 | } else { | |
2773 | list_for_each_entry_rcu(mod, &modules, list) | |
2774 | if ((ret = mod_find_symname(mod, name)) != 0) | |
2775 | break; | |
2776 | } | |
2777 | preempt_enable(); | |
2778 | return ret; | |
2779 | } | |
2780 | ||
2781 | int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, | |
2782 | struct module *, unsigned long), | |
2783 | void *data) | |
2784 | { | |
2785 | struct module *mod; | |
2786 | unsigned int i; | |
2787 | int ret; | |
2788 | ||
2789 | list_for_each_entry(mod, &modules, list) { | |
2790 | for (i = 0; i < mod->num_symtab; i++) { | |
2791 | ret = fn(data, mod->strtab + mod->symtab[i].st_name, | |
2792 | mod, mod->symtab[i].st_value); | |
2793 | if (ret != 0) | |
2794 | return ret; | |
2795 | } | |
2796 | } | |
2797 | return 0; | |
2798 | } | |
2799 | #endif /* CONFIG_KALLSYMS */ | |
2800 | ||
2801 | static char *module_flags(struct module *mod, char *buf) | |
2802 | { | |
2803 | int bx = 0; | |
2804 | ||
2805 | if (mod->taints || | |
2806 | mod->state == MODULE_STATE_GOING || | |
2807 | mod->state == MODULE_STATE_COMING) { | |
2808 | buf[bx++] = '('; | |
2809 | if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE)) | |
2810 | buf[bx++] = 'P'; | |
2811 | if (mod->taints & (1 << TAINT_FORCED_MODULE)) | |
2812 | buf[bx++] = 'F'; | |
2813 | if (mod->taints & (1 << TAINT_CRAP)) | |
2814 | buf[bx++] = 'C'; | |
2815 | /* | |
2816 | * TAINT_FORCED_RMMOD: could be added. | |
2817 | * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't | |
2818 | * apply to modules. | |
2819 | */ | |
2820 | ||
2821 | /* Show a - for module-is-being-unloaded */ | |
2822 | if (mod->state == MODULE_STATE_GOING) | |
2823 | buf[bx++] = '-'; | |
2824 | /* Show a + for module-is-being-loaded */ | |
2825 | if (mod->state == MODULE_STATE_COMING) | |
2826 | buf[bx++] = '+'; | |
2827 | buf[bx++] = ')'; | |
2828 | } | |
2829 | buf[bx] = '\0'; | |
2830 | ||
2831 | return buf; | |
2832 | } | |
2833 | ||
2834 | #ifdef CONFIG_PROC_FS | |
2835 | /* Called by the /proc file system to return a list of modules. */ | |
2836 | static void *m_start(struct seq_file *m, loff_t *pos) | |
2837 | { | |
2838 | mutex_lock(&module_mutex); | |
2839 | return seq_list_start(&modules, *pos); | |
2840 | } | |
2841 | ||
2842 | static void *m_next(struct seq_file *m, void *p, loff_t *pos) | |
2843 | { | |
2844 | return seq_list_next(p, &modules, pos); | |
2845 | } | |
2846 | ||
2847 | static void m_stop(struct seq_file *m, void *p) | |
2848 | { | |
2849 | mutex_unlock(&module_mutex); | |
2850 | } | |
2851 | ||
2852 | static int m_show(struct seq_file *m, void *p) | |
2853 | { | |
2854 | struct module *mod = list_entry(p, struct module, list); | |
2855 | char buf[8]; | |
2856 | ||
2857 | seq_printf(m, "%s %u", | |
2858 | mod->name, mod->init_size + mod->core_size); | |
2859 | print_unload_info(m, mod); | |
2860 | ||
2861 | /* Informative for users. */ | |
2862 | seq_printf(m, " %s", | |
2863 | mod->state == MODULE_STATE_GOING ? "Unloading": | |
2864 | mod->state == MODULE_STATE_COMING ? "Loading": | |
2865 | "Live"); | |
2866 | /* Used by oprofile and other similar tools. */ | |
2867 | seq_printf(m, " 0x%p", mod->module_core); | |
2868 | ||
2869 | /* Taints info */ | |
2870 | if (mod->taints) | |
2871 | seq_printf(m, " %s", module_flags(mod, buf)); | |
2872 | ||
2873 | seq_printf(m, "\n"); | |
2874 | return 0; | |
2875 | } | |
2876 | ||
2877 | /* Format: modulename size refcount deps address | |
2878 | ||
2879 | Where refcount is a number or -, and deps is a comma-separated list | |
2880 | of depends or -. | |
2881 | */ | |
2882 | static const struct seq_operations modules_op = { | |
2883 | .start = m_start, | |
2884 | .next = m_next, | |
2885 | .stop = m_stop, | |
2886 | .show = m_show | |
2887 | }; | |
2888 | ||
2889 | static int modules_open(struct inode *inode, struct file *file) | |
2890 | { | |
2891 | return seq_open(file, &modules_op); | |
2892 | } | |
2893 | ||
2894 | static const struct file_operations proc_modules_operations = { | |
2895 | .open = modules_open, | |
2896 | .read = seq_read, | |
2897 | .llseek = seq_lseek, | |
2898 | .release = seq_release, | |
2899 | }; | |
2900 | ||
2901 | static int __init proc_modules_init(void) | |
2902 | { | |
2903 | proc_create("modules", 0, NULL, &proc_modules_operations); | |
2904 | return 0; | |
2905 | } | |
2906 | module_init(proc_modules_init); | |
2907 | #endif | |
2908 | ||
2909 | /* Given an address, look for it in the module exception tables. */ | |
2910 | const struct exception_table_entry *search_module_extables(unsigned long addr) | |
2911 | { | |
2912 | const struct exception_table_entry *e = NULL; | |
2913 | struct module *mod; | |
2914 | ||
2915 | preempt_disable(); | |
2916 | list_for_each_entry_rcu(mod, &modules, list) { | |
2917 | if (mod->num_exentries == 0) | |
2918 | continue; | |
2919 | ||
2920 | e = search_extable(mod->extable, | |
2921 | mod->extable + mod->num_exentries - 1, | |
2922 | addr); | |
2923 | if (e) | |
2924 | break; | |
2925 | } | |
2926 | preempt_enable(); | |
2927 | ||
2928 | /* Now, if we found one, we are running inside it now, hence | |
2929 | we cannot unload the module, hence no refcnt needed. */ | |
2930 | return e; | |
2931 | } | |
2932 | ||
2933 | /* | |
2934 | * is_module_address - is this address inside a module? | |
2935 | * @addr: the address to check. | |
2936 | * | |
2937 | * See is_module_text_address() if you simply want to see if the address | |
2938 | * is code (not data). | |
2939 | */ | |
2940 | bool is_module_address(unsigned long addr) | |
2941 | { | |
2942 | bool ret; | |
2943 | ||
2944 | preempt_disable(); | |
2945 | ret = __module_address(addr) != NULL; | |
2946 | preempt_enable(); | |
2947 | ||
2948 | return ret; | |
2949 | } | |
2950 | ||
2951 | /* | |
2952 | * __module_address - get the module which contains an address. | |
2953 | * @addr: the address. | |
2954 | * | |
2955 | * Must be called with preempt disabled or module mutex held so that | |
2956 | * module doesn't get freed during this. | |
2957 | */ | |
2958 | struct module *__module_address(unsigned long addr) | |
2959 | { | |
2960 | struct module *mod; | |
2961 | ||
2962 | if (addr < module_addr_min || addr > module_addr_max) | |
2963 | return NULL; | |
2964 | ||
2965 | list_for_each_entry_rcu(mod, &modules, list) | |
2966 | if (within_module_core(addr, mod) | |
2967 | || within_module_init(addr, mod)) | |
2968 | return mod; | |
2969 | return NULL; | |
2970 | } | |
2971 | EXPORT_SYMBOL_GPL(__module_address); | |
2972 | ||
2973 | /* | |
2974 | * is_module_text_address - is this address inside module code? | |
2975 | * @addr: the address to check. | |
2976 | * | |
2977 | * See is_module_address() if you simply want to see if the address is | |
2978 | * anywhere in a module. See kernel_text_address() for testing if an | |
2979 | * address corresponds to kernel or module code. | |
2980 | */ | |
2981 | bool is_module_text_address(unsigned long addr) | |
2982 | { | |
2983 | bool ret; | |
2984 | ||
2985 | preempt_disable(); | |
2986 | ret = __module_text_address(addr) != NULL; | |
2987 | preempt_enable(); | |
2988 | ||
2989 | return ret; | |
2990 | } | |
2991 | ||
2992 | /* | |
2993 | * __module_text_address - get the module whose code contains an address. | |
2994 | * @addr: the address. | |
2995 | * | |
2996 | * Must be called with preempt disabled or module mutex held so that | |
2997 | * module doesn't get freed during this. | |
2998 | */ | |
2999 | struct module *__module_text_address(unsigned long addr) | |
3000 | { | |
3001 | struct module *mod = __module_address(addr); | |
3002 | if (mod) { | |
3003 | /* Make sure it's within the text section. */ | |
3004 | if (!within(addr, mod->module_init, mod->init_text_size) | |
3005 | && !within(addr, mod->module_core, mod->core_text_size)) | |
3006 | mod = NULL; | |
3007 | } | |
3008 | return mod; | |
3009 | } | |
3010 | EXPORT_SYMBOL_GPL(__module_text_address); | |
3011 | ||
3012 | /* Don't grab lock, we're oopsing. */ | |
3013 | void print_modules(void) | |
3014 | { | |
3015 | struct module *mod; | |
3016 | char buf[8]; | |
3017 | ||
3018 | printk(KERN_DEFAULT "Modules linked in:"); | |
3019 | /* Most callers should already have preempt disabled, but make sure */ | |
3020 | preempt_disable(); | |
3021 | list_for_each_entry_rcu(mod, &modules, list) | |
3022 | printk(" %s%s", mod->name, module_flags(mod, buf)); | |
3023 | preempt_enable(); | |
3024 | if (last_unloaded_module[0]) | |
3025 | printk(" [last unloaded: %s]", last_unloaded_module); | |
3026 | printk("\n"); | |
3027 | } | |
3028 | ||
3029 | #ifdef CONFIG_MODVERSIONS | |
3030 | /* Generate the signature for all relevant module structures here. | |
3031 | * If these change, we don't want to try to parse the module. */ | |
3032 | void module_layout(struct module *mod, | |
3033 | struct modversion_info *ver, | |
3034 | struct kernel_param *kp, | |
3035 | struct kernel_symbol *ks, | |
3036 | struct tracepoint *tp) | |
3037 | { | |
3038 | } | |
3039 | EXPORT_SYMBOL(module_layout); | |
3040 | #endif | |
3041 | ||
3042 | #ifdef CONFIG_TRACEPOINTS | |
3043 | void module_update_tracepoints(void) | |
3044 | { | |
3045 | struct module *mod; | |
3046 | ||
3047 | mutex_lock(&module_mutex); | |
3048 | list_for_each_entry(mod, &modules, list) | |
3049 | if (!mod->taints) | |
3050 | tracepoint_update_probe_range(mod->tracepoints, | |
3051 | mod->tracepoints + mod->num_tracepoints); | |
3052 | mutex_unlock(&module_mutex); | |
3053 | } | |
3054 | ||
3055 | /* | |
3056 | * Returns 0 if current not found. | |
3057 | * Returns 1 if current found. | |
3058 | */ | |
3059 | int module_get_iter_tracepoints(struct tracepoint_iter *iter) | |
3060 | { | |
3061 | struct module *iter_mod; | |
3062 | int found = 0; | |
3063 | ||
3064 | mutex_lock(&module_mutex); | |
3065 | list_for_each_entry(iter_mod, &modules, list) { | |
3066 | if (!iter_mod->taints) { | |
3067 | /* | |
3068 | * Sorted module list | |
3069 | */ | |
3070 | if (iter_mod < iter->module) | |
3071 | continue; | |
3072 | else if (iter_mod > iter->module) | |
3073 | iter->tracepoint = NULL; | |
3074 | found = tracepoint_get_iter_range(&iter->tracepoint, | |
3075 | iter_mod->tracepoints, | |
3076 | iter_mod->tracepoints | |
3077 | + iter_mod->num_tracepoints); | |
3078 | if (found) { | |
3079 | iter->module = iter_mod; | |
3080 | break; | |
3081 | } | |
3082 | } | |
3083 | } | |
3084 | mutex_unlock(&module_mutex); | |
3085 | return found; | |
3086 | } | |
3087 | #endif |