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1 | /* | |
2 | Copyright (C) 2002 Richard Henderson | |
3 | Copyright (C) 2001 Rusty Russell, 2002, 2010 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 | /* | |
76 | * Mutex protects: | |
77 | * 1) List of modules (also safely readable with preempt_disable), | |
78 | * 2) module_use links, | |
79 | * 3) module_addr_min/module_addr_max. | |
80 | * (delete uses stop_machine/add uses RCU list operations). */ | |
81 | DEFINE_MUTEX(module_mutex); | |
82 | EXPORT_SYMBOL_GPL(module_mutex); | |
83 | static LIST_HEAD(modules); | |
84 | #ifdef CONFIG_KGDB_KDB | |
85 | struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ | |
86 | #endif /* CONFIG_KGDB_KDB */ | |
87 | ||
88 | ||
89 | /* Block module loading/unloading? */ | |
90 | int modules_disabled = 0; | |
91 | ||
92 | /* Waiting for a module to finish initializing? */ | |
93 | static DECLARE_WAIT_QUEUE_HEAD(module_wq); | |
94 | ||
95 | static BLOCKING_NOTIFIER_HEAD(module_notify_list); | |
96 | ||
97 | /* Bounds of module allocation, for speeding __module_address. | |
98 | * Protected by module_mutex. */ | |
99 | static unsigned long module_addr_min = -1UL, module_addr_max = 0; | |
100 | ||
101 | int register_module_notifier(struct notifier_block * nb) | |
102 | { | |
103 | return blocking_notifier_chain_register(&module_notify_list, nb); | |
104 | } | |
105 | EXPORT_SYMBOL(register_module_notifier); | |
106 | ||
107 | int unregister_module_notifier(struct notifier_block * nb) | |
108 | { | |
109 | return blocking_notifier_chain_unregister(&module_notify_list, nb); | |
110 | } | |
111 | EXPORT_SYMBOL(unregister_module_notifier); | |
112 | ||
113 | struct load_info { | |
114 | Elf_Ehdr *hdr; | |
115 | unsigned long len; | |
116 | Elf_Shdr *sechdrs; | |
117 | char *secstrings, *strtab; | |
118 | unsigned long *strmap; | |
119 | unsigned long symoffs, stroffs; | |
120 | struct _ddebug *debug; | |
121 | unsigned int num_debug; | |
122 | struct { | |
123 | unsigned int sym, str, mod, vers, info, pcpu; | |
124 | } index; | |
125 | }; | |
126 | ||
127 | /* We require a truly strong try_module_get(): 0 means failure due to | |
128 | ongoing or failed initialization etc. */ | |
129 | static inline int strong_try_module_get(struct module *mod) | |
130 | { | |
131 | if (mod && mod->state == MODULE_STATE_COMING) | |
132 | return -EBUSY; | |
133 | if (try_module_get(mod)) | |
134 | return 0; | |
135 | else | |
136 | return -ENOENT; | |
137 | } | |
138 | ||
139 | static inline void add_taint_module(struct module *mod, unsigned flag) | |
140 | { | |
141 | add_taint(flag); | |
142 | mod->taints |= (1U << flag); | |
143 | } | |
144 | ||
145 | /* | |
146 | * A thread that wants to hold a reference to a module only while it | |
147 | * is running can call this to safely exit. nfsd and lockd use this. | |
148 | */ | |
149 | void __module_put_and_exit(struct module *mod, long code) | |
150 | { | |
151 | module_put(mod); | |
152 | do_exit(code); | |
153 | } | |
154 | EXPORT_SYMBOL(__module_put_and_exit); | |
155 | ||
156 | /* Find a module section: 0 means not found. */ | |
157 | static unsigned int find_sec(const struct load_info *info, const char *name) | |
158 | { | |
159 | unsigned int i; | |
160 | ||
161 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
162 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
163 | /* Alloc bit cleared means "ignore it." */ | |
164 | if ((shdr->sh_flags & SHF_ALLOC) | |
165 | && strcmp(info->secstrings + shdr->sh_name, name) == 0) | |
166 | return i; | |
167 | } | |
168 | return 0; | |
169 | } | |
170 | ||
171 | /* Find a module section, or NULL. */ | |
172 | static void *section_addr(const struct load_info *info, const char *name) | |
173 | { | |
174 | /* Section 0 has sh_addr 0. */ | |
175 | return (void *)info->sechdrs[find_sec(info, name)].sh_addr; | |
176 | } | |
177 | ||
178 | /* Find a module section, or NULL. Fill in number of "objects" in section. */ | |
179 | static void *section_objs(const struct load_info *info, | |
180 | const char *name, | |
181 | size_t object_size, | |
182 | unsigned int *num) | |
183 | { | |
184 | unsigned int sec = find_sec(info, name); | |
185 | ||
186 | /* Section 0 has sh_addr 0 and sh_size 0. */ | |
187 | *num = info->sechdrs[sec].sh_size / object_size; | |
188 | return (void *)info->sechdrs[sec].sh_addr; | |
189 | } | |
190 | ||
191 | /* Provided by the linker */ | |
192 | extern const struct kernel_symbol __start___ksymtab[]; | |
193 | extern const struct kernel_symbol __stop___ksymtab[]; | |
194 | extern const struct kernel_symbol __start___ksymtab_gpl[]; | |
195 | extern const struct kernel_symbol __stop___ksymtab_gpl[]; | |
196 | extern const struct kernel_symbol __start___ksymtab_gpl_future[]; | |
197 | extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; | |
198 | extern const unsigned long __start___kcrctab[]; | |
199 | extern const unsigned long __start___kcrctab_gpl[]; | |
200 | extern const unsigned long __start___kcrctab_gpl_future[]; | |
201 | #ifdef CONFIG_UNUSED_SYMBOLS | |
202 | extern const struct kernel_symbol __start___ksymtab_unused[]; | |
203 | extern const struct kernel_symbol __stop___ksymtab_unused[]; | |
204 | extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; | |
205 | extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; | |
206 | extern const unsigned long __start___kcrctab_unused[]; | |
207 | extern const unsigned long __start___kcrctab_unused_gpl[]; | |
208 | #endif | |
209 | ||
210 | #ifndef CONFIG_MODVERSIONS | |
211 | #define symversion(base, idx) NULL | |
212 | #else | |
213 | #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL) | |
214 | #endif | |
215 | ||
216 | static bool each_symbol_in_section(const struct symsearch *arr, | |
217 | unsigned int arrsize, | |
218 | struct module *owner, | |
219 | bool (*fn)(const struct symsearch *syms, | |
220 | struct module *owner, | |
221 | unsigned int symnum, void *data), | |
222 | void *data) | |
223 | { | |
224 | unsigned int i, j; | |
225 | ||
226 | for (j = 0; j < arrsize; j++) { | |
227 | for (i = 0; i < arr[j].stop - arr[j].start; i++) | |
228 | if (fn(&arr[j], owner, i, data)) | |
229 | return true; | |
230 | } | |
231 | ||
232 | return false; | |
233 | } | |
234 | ||
235 | /* Returns true as soon as fn returns true, otherwise false. */ | |
236 | bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner, | |
237 | unsigned int symnum, void *data), void *data) | |
238 | { | |
239 | struct module *mod; | |
240 | static const struct symsearch arr[] = { | |
241 | { __start___ksymtab, __stop___ksymtab, __start___kcrctab, | |
242 | NOT_GPL_ONLY, false }, | |
243 | { __start___ksymtab_gpl, __stop___ksymtab_gpl, | |
244 | __start___kcrctab_gpl, | |
245 | GPL_ONLY, false }, | |
246 | { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future, | |
247 | __start___kcrctab_gpl_future, | |
248 | WILL_BE_GPL_ONLY, false }, | |
249 | #ifdef CONFIG_UNUSED_SYMBOLS | |
250 | { __start___ksymtab_unused, __stop___ksymtab_unused, | |
251 | __start___kcrctab_unused, | |
252 | NOT_GPL_ONLY, true }, | |
253 | { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl, | |
254 | __start___kcrctab_unused_gpl, | |
255 | GPL_ONLY, true }, | |
256 | #endif | |
257 | }; | |
258 | ||
259 | if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data)) | |
260 | return true; | |
261 | ||
262 | list_for_each_entry_rcu(mod, &modules, list) { | |
263 | struct symsearch arr[] = { | |
264 | { mod->syms, mod->syms + mod->num_syms, mod->crcs, | |
265 | NOT_GPL_ONLY, false }, | |
266 | { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, | |
267 | mod->gpl_crcs, | |
268 | GPL_ONLY, false }, | |
269 | { mod->gpl_future_syms, | |
270 | mod->gpl_future_syms + mod->num_gpl_future_syms, | |
271 | mod->gpl_future_crcs, | |
272 | WILL_BE_GPL_ONLY, false }, | |
273 | #ifdef CONFIG_UNUSED_SYMBOLS | |
274 | { mod->unused_syms, | |
275 | mod->unused_syms + mod->num_unused_syms, | |
276 | mod->unused_crcs, | |
277 | NOT_GPL_ONLY, true }, | |
278 | { mod->unused_gpl_syms, | |
279 | mod->unused_gpl_syms + mod->num_unused_gpl_syms, | |
280 | mod->unused_gpl_crcs, | |
281 | GPL_ONLY, true }, | |
282 | #endif | |
283 | }; | |
284 | ||
285 | if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data)) | |
286 | return true; | |
287 | } | |
288 | return false; | |
289 | } | |
290 | EXPORT_SYMBOL_GPL(each_symbol); | |
291 | ||
292 | struct find_symbol_arg { | |
293 | /* Input */ | |
294 | const char *name; | |
295 | bool gplok; | |
296 | bool warn; | |
297 | ||
298 | /* Output */ | |
299 | struct module *owner; | |
300 | const unsigned long *crc; | |
301 | const struct kernel_symbol *sym; | |
302 | }; | |
303 | ||
304 | static bool find_symbol_in_section(const struct symsearch *syms, | |
305 | struct module *owner, | |
306 | unsigned int symnum, void *data) | |
307 | { | |
308 | struct find_symbol_arg *fsa = data; | |
309 | ||
310 | if (strcmp(syms->start[symnum].name, fsa->name) != 0) | |
311 | return false; | |
312 | ||
313 | if (!fsa->gplok) { | |
314 | if (syms->licence == GPL_ONLY) | |
315 | return false; | |
316 | if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) { | |
317 | printk(KERN_WARNING "Symbol %s is being used " | |
318 | "by a non-GPL module, which will not " | |
319 | "be allowed in the future\n", fsa->name); | |
320 | printk(KERN_WARNING "Please see the file " | |
321 | "Documentation/feature-removal-schedule.txt " | |
322 | "in the kernel source tree for more details.\n"); | |
323 | } | |
324 | } | |
325 | ||
326 | #ifdef CONFIG_UNUSED_SYMBOLS | |
327 | if (syms->unused && fsa->warn) { | |
328 | printk(KERN_WARNING "Symbol %s is marked as UNUSED, " | |
329 | "however this module is using it.\n", fsa->name); | |
330 | printk(KERN_WARNING | |
331 | "This symbol will go away in the future.\n"); | |
332 | printk(KERN_WARNING | |
333 | "Please evalute if this is the right api to use and if " | |
334 | "it really is, submit a report the linux kernel " | |
335 | "mailinglist together with submitting your code for " | |
336 | "inclusion.\n"); | |
337 | } | |
338 | #endif | |
339 | ||
340 | fsa->owner = owner; | |
341 | fsa->crc = symversion(syms->crcs, symnum); | |
342 | fsa->sym = &syms->start[symnum]; | |
343 | return true; | |
344 | } | |
345 | ||
346 | /* Find a symbol and return it, along with, (optional) crc and | |
347 | * (optional) module which owns it. Needs preempt disabled or module_mutex. */ | |
348 | const struct kernel_symbol *find_symbol(const char *name, | |
349 | struct module **owner, | |
350 | const unsigned long **crc, | |
351 | bool gplok, | |
352 | bool warn) | |
353 | { | |
354 | struct find_symbol_arg fsa; | |
355 | ||
356 | fsa.name = name; | |
357 | fsa.gplok = gplok; | |
358 | fsa.warn = warn; | |
359 | ||
360 | if (each_symbol(find_symbol_in_section, &fsa)) { | |
361 | if (owner) | |
362 | *owner = fsa.owner; | |
363 | if (crc) | |
364 | *crc = fsa.crc; | |
365 | return fsa.sym; | |
366 | } | |
367 | ||
368 | DEBUGP("Failed to find symbol %s\n", name); | |
369 | return NULL; | |
370 | } | |
371 | EXPORT_SYMBOL_GPL(find_symbol); | |
372 | ||
373 | /* Search for module by name: must hold module_mutex. */ | |
374 | struct module *find_module(const char *name) | |
375 | { | |
376 | struct module *mod; | |
377 | ||
378 | list_for_each_entry(mod, &modules, list) { | |
379 | if (strcmp(mod->name, name) == 0) | |
380 | return mod; | |
381 | } | |
382 | return NULL; | |
383 | } | |
384 | EXPORT_SYMBOL_GPL(find_module); | |
385 | ||
386 | #ifdef CONFIG_SMP | |
387 | ||
388 | static inline void __percpu *mod_percpu(struct module *mod) | |
389 | { | |
390 | return mod->percpu; | |
391 | } | |
392 | ||
393 | static int percpu_modalloc(struct module *mod, | |
394 | unsigned long size, unsigned long align) | |
395 | { | |
396 | if (align > PAGE_SIZE) { | |
397 | printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n", | |
398 | mod->name, align, PAGE_SIZE); | |
399 | align = PAGE_SIZE; | |
400 | } | |
401 | ||
402 | mod->percpu = __alloc_reserved_percpu(size, align); | |
403 | if (!mod->percpu) { | |
404 | printk(KERN_WARNING | |
405 | "%s: Could not allocate %lu bytes percpu data\n", | |
406 | mod->name, size); | |
407 | return -ENOMEM; | |
408 | } | |
409 | mod->percpu_size = size; | |
410 | return 0; | |
411 | } | |
412 | ||
413 | static void percpu_modfree(struct module *mod) | |
414 | { | |
415 | free_percpu(mod->percpu); | |
416 | } | |
417 | ||
418 | static unsigned int find_pcpusec(struct load_info *info) | |
419 | { | |
420 | return find_sec(info, ".data..percpu"); | |
421 | } | |
422 | ||
423 | static void percpu_modcopy(struct module *mod, | |
424 | const void *from, unsigned long size) | |
425 | { | |
426 | int cpu; | |
427 | ||
428 | for_each_possible_cpu(cpu) | |
429 | memcpy(per_cpu_ptr(mod->percpu, cpu), from, size); | |
430 | } | |
431 | ||
432 | /** | |
433 | * is_module_percpu_address - test whether address is from module static percpu | |
434 | * @addr: address to test | |
435 | * | |
436 | * Test whether @addr belongs to module static percpu area. | |
437 | * | |
438 | * RETURNS: | |
439 | * %true if @addr is from module static percpu area | |
440 | */ | |
441 | bool is_module_percpu_address(unsigned long addr) | |
442 | { | |
443 | struct module *mod; | |
444 | unsigned int cpu; | |
445 | ||
446 | preempt_disable(); | |
447 | ||
448 | list_for_each_entry_rcu(mod, &modules, list) { | |
449 | if (!mod->percpu_size) | |
450 | continue; | |
451 | for_each_possible_cpu(cpu) { | |
452 | void *start = per_cpu_ptr(mod->percpu, cpu); | |
453 | ||
454 | if ((void *)addr >= start && | |
455 | (void *)addr < start + mod->percpu_size) { | |
456 | preempt_enable(); | |
457 | return true; | |
458 | } | |
459 | } | |
460 | } | |
461 | ||
462 | preempt_enable(); | |
463 | return false; | |
464 | } | |
465 | ||
466 | #else /* ... !CONFIG_SMP */ | |
467 | ||
468 | static inline void __percpu *mod_percpu(struct module *mod) | |
469 | { | |
470 | return NULL; | |
471 | } | |
472 | static inline int percpu_modalloc(struct module *mod, | |
473 | unsigned long size, unsigned long align) | |
474 | { | |
475 | return -ENOMEM; | |
476 | } | |
477 | static inline void percpu_modfree(struct module *mod) | |
478 | { | |
479 | } | |
480 | static unsigned int find_pcpusec(struct load_info *info) | |
481 | { | |
482 | return 0; | |
483 | } | |
484 | static inline void percpu_modcopy(struct module *mod, | |
485 | const void *from, unsigned long size) | |
486 | { | |
487 | /* pcpusec should be 0, and size of that section should be 0. */ | |
488 | BUG_ON(size != 0); | |
489 | } | |
490 | bool is_module_percpu_address(unsigned long addr) | |
491 | { | |
492 | return false; | |
493 | } | |
494 | ||
495 | #endif /* CONFIG_SMP */ | |
496 | ||
497 | #define MODINFO_ATTR(field) \ | |
498 | static void setup_modinfo_##field(struct module *mod, const char *s) \ | |
499 | { \ | |
500 | mod->field = kstrdup(s, GFP_KERNEL); \ | |
501 | } \ | |
502 | static ssize_t show_modinfo_##field(struct module_attribute *mattr, \ | |
503 | struct module *mod, char *buffer) \ | |
504 | { \ | |
505 | return sprintf(buffer, "%s\n", mod->field); \ | |
506 | } \ | |
507 | static int modinfo_##field##_exists(struct module *mod) \ | |
508 | { \ | |
509 | return mod->field != NULL; \ | |
510 | } \ | |
511 | static void free_modinfo_##field(struct module *mod) \ | |
512 | { \ | |
513 | kfree(mod->field); \ | |
514 | mod->field = NULL; \ | |
515 | } \ | |
516 | static struct module_attribute modinfo_##field = { \ | |
517 | .attr = { .name = __stringify(field), .mode = 0444 }, \ | |
518 | .show = show_modinfo_##field, \ | |
519 | .setup = setup_modinfo_##field, \ | |
520 | .test = modinfo_##field##_exists, \ | |
521 | .free = free_modinfo_##field, \ | |
522 | }; | |
523 | ||
524 | MODINFO_ATTR(version); | |
525 | MODINFO_ATTR(srcversion); | |
526 | ||
527 | static char last_unloaded_module[MODULE_NAME_LEN+1]; | |
528 | ||
529 | #ifdef CONFIG_MODULE_UNLOAD | |
530 | ||
531 | EXPORT_TRACEPOINT_SYMBOL(module_get); | |
532 | ||
533 | /* Init the unload section of the module. */ | |
534 | static int module_unload_init(struct module *mod) | |
535 | { | |
536 | mod->refptr = alloc_percpu(struct module_ref); | |
537 | if (!mod->refptr) | |
538 | return -ENOMEM; | |
539 | ||
540 | INIT_LIST_HEAD(&mod->source_list); | |
541 | INIT_LIST_HEAD(&mod->target_list); | |
542 | ||
543 | /* Hold reference count during initialization. */ | |
544 | __this_cpu_write(mod->refptr->incs, 1); | |
545 | /* Backwards compatibility macros put refcount during init. */ | |
546 | mod->waiter = current; | |
547 | ||
548 | return 0; | |
549 | } | |
550 | ||
551 | /* Does a already use b? */ | |
552 | static int already_uses(struct module *a, struct module *b) | |
553 | { | |
554 | struct module_use *use; | |
555 | ||
556 | list_for_each_entry(use, &b->source_list, source_list) { | |
557 | if (use->source == a) { | |
558 | DEBUGP("%s uses %s!\n", a->name, b->name); | |
559 | return 1; | |
560 | } | |
561 | } | |
562 | DEBUGP("%s does not use %s!\n", a->name, b->name); | |
563 | return 0; | |
564 | } | |
565 | ||
566 | /* | |
567 | * Module a uses b | |
568 | * - we add 'a' as a "source", 'b' as a "target" of module use | |
569 | * - the module_use is added to the list of 'b' sources (so | |
570 | * 'b' can walk the list to see who sourced them), and of 'a' | |
571 | * targets (so 'a' can see what modules it targets). | |
572 | */ | |
573 | static int add_module_usage(struct module *a, struct module *b) | |
574 | { | |
575 | struct module_use *use; | |
576 | ||
577 | DEBUGP("Allocating new usage for %s.\n", a->name); | |
578 | use = kmalloc(sizeof(*use), GFP_ATOMIC); | |
579 | if (!use) { | |
580 | printk(KERN_WARNING "%s: out of memory loading\n", a->name); | |
581 | return -ENOMEM; | |
582 | } | |
583 | ||
584 | use->source = a; | |
585 | use->target = b; | |
586 | list_add(&use->source_list, &b->source_list); | |
587 | list_add(&use->target_list, &a->target_list); | |
588 | return 0; | |
589 | } | |
590 | ||
591 | /* Module a uses b: caller needs module_mutex() */ | |
592 | int ref_module(struct module *a, struct module *b) | |
593 | { | |
594 | int err; | |
595 | ||
596 | if (b == NULL || already_uses(a, b)) | |
597 | return 0; | |
598 | ||
599 | /* If module isn't available, we fail. */ | |
600 | err = strong_try_module_get(b); | |
601 | if (err) | |
602 | return err; | |
603 | ||
604 | err = add_module_usage(a, b); | |
605 | if (err) { | |
606 | module_put(b); | |
607 | return err; | |
608 | } | |
609 | return 0; | |
610 | } | |
611 | EXPORT_SYMBOL_GPL(ref_module); | |
612 | ||
613 | /* Clear the unload stuff of the module. */ | |
614 | static void module_unload_free(struct module *mod) | |
615 | { | |
616 | struct module_use *use, *tmp; | |
617 | ||
618 | mutex_lock(&module_mutex); | |
619 | list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) { | |
620 | struct module *i = use->target; | |
621 | DEBUGP("%s unusing %s\n", mod->name, i->name); | |
622 | module_put(i); | |
623 | list_del(&use->source_list); | |
624 | list_del(&use->target_list); | |
625 | kfree(use); | |
626 | } | |
627 | mutex_unlock(&module_mutex); | |
628 | ||
629 | free_percpu(mod->refptr); | |
630 | } | |
631 | ||
632 | #ifdef CONFIG_MODULE_FORCE_UNLOAD | |
633 | static inline int try_force_unload(unsigned int flags) | |
634 | { | |
635 | int ret = (flags & O_TRUNC); | |
636 | if (ret) | |
637 | add_taint(TAINT_FORCED_RMMOD); | |
638 | return ret; | |
639 | } | |
640 | #else | |
641 | static inline int try_force_unload(unsigned int flags) | |
642 | { | |
643 | return 0; | |
644 | } | |
645 | #endif /* CONFIG_MODULE_FORCE_UNLOAD */ | |
646 | ||
647 | struct stopref | |
648 | { | |
649 | struct module *mod; | |
650 | int flags; | |
651 | int *forced; | |
652 | }; | |
653 | ||
654 | /* Whole machine is stopped with interrupts off when this runs. */ | |
655 | static int __try_stop_module(void *_sref) | |
656 | { | |
657 | struct stopref *sref = _sref; | |
658 | ||
659 | /* If it's not unused, quit unless we're forcing. */ | |
660 | if (module_refcount(sref->mod) != 0) { | |
661 | if (!(*sref->forced = try_force_unload(sref->flags))) | |
662 | return -EWOULDBLOCK; | |
663 | } | |
664 | ||
665 | /* Mark it as dying. */ | |
666 | sref->mod->state = MODULE_STATE_GOING; | |
667 | return 0; | |
668 | } | |
669 | ||
670 | static int try_stop_module(struct module *mod, int flags, int *forced) | |
671 | { | |
672 | if (flags & O_NONBLOCK) { | |
673 | struct stopref sref = { mod, flags, forced }; | |
674 | ||
675 | return stop_machine(__try_stop_module, &sref, NULL); | |
676 | } else { | |
677 | /* We don't need to stop the machine for this. */ | |
678 | mod->state = MODULE_STATE_GOING; | |
679 | synchronize_sched(); | |
680 | return 0; | |
681 | } | |
682 | } | |
683 | ||
684 | unsigned int module_refcount(struct module *mod) | |
685 | { | |
686 | unsigned int incs = 0, decs = 0; | |
687 | int cpu; | |
688 | ||
689 | for_each_possible_cpu(cpu) | |
690 | decs += per_cpu_ptr(mod->refptr, cpu)->decs; | |
691 | /* | |
692 | * ensure the incs are added up after the decs. | |
693 | * module_put ensures incs are visible before decs with smp_wmb. | |
694 | * | |
695 | * This 2-count scheme avoids the situation where the refcount | |
696 | * for CPU0 is read, then CPU0 increments the module refcount, | |
697 | * then CPU1 drops that refcount, then the refcount for CPU1 is | |
698 | * read. We would record a decrement but not its corresponding | |
699 | * increment so we would see a low count (disaster). | |
700 | * | |
701 | * Rare situation? But module_refcount can be preempted, and we | |
702 | * might be tallying up 4096+ CPUs. So it is not impossible. | |
703 | */ | |
704 | smp_rmb(); | |
705 | for_each_possible_cpu(cpu) | |
706 | incs += per_cpu_ptr(mod->refptr, cpu)->incs; | |
707 | return incs - decs; | |
708 | } | |
709 | EXPORT_SYMBOL(module_refcount); | |
710 | ||
711 | /* This exists whether we can unload or not */ | |
712 | static void free_module(struct module *mod); | |
713 | ||
714 | static void wait_for_zero_refcount(struct module *mod) | |
715 | { | |
716 | /* Since we might sleep for some time, release the mutex first */ | |
717 | mutex_unlock(&module_mutex); | |
718 | for (;;) { | |
719 | DEBUGP("Looking at refcount...\n"); | |
720 | set_current_state(TASK_UNINTERRUPTIBLE); | |
721 | if (module_refcount(mod) == 0) | |
722 | break; | |
723 | schedule(); | |
724 | } | |
725 | current->state = TASK_RUNNING; | |
726 | mutex_lock(&module_mutex); | |
727 | } | |
728 | ||
729 | SYSCALL_DEFINE2(delete_module, const char __user *, name_user, | |
730 | unsigned int, flags) | |
731 | { | |
732 | struct module *mod; | |
733 | char name[MODULE_NAME_LEN]; | |
734 | int ret, forced = 0; | |
735 | ||
736 | if (!capable(CAP_SYS_MODULE) || modules_disabled) | |
737 | return -EPERM; | |
738 | ||
739 | if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) | |
740 | return -EFAULT; | |
741 | name[MODULE_NAME_LEN-1] = '\0'; | |
742 | ||
743 | if (mutex_lock_interruptible(&module_mutex) != 0) | |
744 | return -EINTR; | |
745 | ||
746 | mod = find_module(name); | |
747 | if (!mod) { | |
748 | ret = -ENOENT; | |
749 | goto out; | |
750 | } | |
751 | ||
752 | if (!list_empty(&mod->source_list)) { | |
753 | /* Other modules depend on us: get rid of them first. */ | |
754 | ret = -EWOULDBLOCK; | |
755 | goto out; | |
756 | } | |
757 | ||
758 | /* Doing init or already dying? */ | |
759 | if (mod->state != MODULE_STATE_LIVE) { | |
760 | /* FIXME: if (force), slam module count and wake up | |
761 | waiter --RR */ | |
762 | DEBUGP("%s already dying\n", mod->name); | |
763 | ret = -EBUSY; | |
764 | goto out; | |
765 | } | |
766 | ||
767 | /* If it has an init func, it must have an exit func to unload */ | |
768 | if (mod->init && !mod->exit) { | |
769 | forced = try_force_unload(flags); | |
770 | if (!forced) { | |
771 | /* This module can't be removed */ | |
772 | ret = -EBUSY; | |
773 | goto out; | |
774 | } | |
775 | } | |
776 | ||
777 | /* Set this up before setting mod->state */ | |
778 | mod->waiter = current; | |
779 | ||
780 | /* Stop the machine so refcounts can't move and disable module. */ | |
781 | ret = try_stop_module(mod, flags, &forced); | |
782 | if (ret != 0) | |
783 | goto out; | |
784 | ||
785 | /* Never wait if forced. */ | |
786 | if (!forced && module_refcount(mod) != 0) | |
787 | wait_for_zero_refcount(mod); | |
788 | ||
789 | mutex_unlock(&module_mutex); | |
790 | /* Final destruction now noone is using it. */ | |
791 | if (mod->exit != NULL) | |
792 | mod->exit(); | |
793 | blocking_notifier_call_chain(&module_notify_list, | |
794 | MODULE_STATE_GOING, mod); | |
795 | async_synchronize_full(); | |
796 | ||
797 | /* Store the name of the last unloaded module for diagnostic purposes */ | |
798 | strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); | |
799 | ||
800 | free_module(mod); | |
801 | return 0; | |
802 | out: | |
803 | mutex_unlock(&module_mutex); | |
804 | return ret; | |
805 | } | |
806 | ||
807 | static inline void print_unload_info(struct seq_file *m, struct module *mod) | |
808 | { | |
809 | struct module_use *use; | |
810 | int printed_something = 0; | |
811 | ||
812 | seq_printf(m, " %u ", module_refcount(mod)); | |
813 | ||
814 | /* Always include a trailing , so userspace can differentiate | |
815 | between this and the old multi-field proc format. */ | |
816 | list_for_each_entry(use, &mod->source_list, source_list) { | |
817 | printed_something = 1; | |
818 | seq_printf(m, "%s,", use->source->name); | |
819 | } | |
820 | ||
821 | if (mod->init != NULL && mod->exit == NULL) { | |
822 | printed_something = 1; | |
823 | seq_printf(m, "[permanent],"); | |
824 | } | |
825 | ||
826 | if (!printed_something) | |
827 | seq_printf(m, "-"); | |
828 | } | |
829 | ||
830 | void __symbol_put(const char *symbol) | |
831 | { | |
832 | struct module *owner; | |
833 | ||
834 | preempt_disable(); | |
835 | if (!find_symbol(symbol, &owner, NULL, true, false)) | |
836 | BUG(); | |
837 | module_put(owner); | |
838 | preempt_enable(); | |
839 | } | |
840 | EXPORT_SYMBOL(__symbol_put); | |
841 | ||
842 | /* Note this assumes addr is a function, which it currently always is. */ | |
843 | void symbol_put_addr(void *addr) | |
844 | { | |
845 | struct module *modaddr; | |
846 | unsigned long a = (unsigned long)dereference_function_descriptor(addr); | |
847 | ||
848 | if (core_kernel_text(a)) | |
849 | return; | |
850 | ||
851 | /* module_text_address is safe here: we're supposed to have reference | |
852 | * to module from symbol_get, so it can't go away. */ | |
853 | modaddr = __module_text_address(a); | |
854 | BUG_ON(!modaddr); | |
855 | module_put(modaddr); | |
856 | } | |
857 | EXPORT_SYMBOL_GPL(symbol_put_addr); | |
858 | ||
859 | static ssize_t show_refcnt(struct module_attribute *mattr, | |
860 | struct module *mod, char *buffer) | |
861 | { | |
862 | return sprintf(buffer, "%u\n", module_refcount(mod)); | |
863 | } | |
864 | ||
865 | static struct module_attribute refcnt = { | |
866 | .attr = { .name = "refcnt", .mode = 0444 }, | |
867 | .show = show_refcnt, | |
868 | }; | |
869 | ||
870 | void module_put(struct module *module) | |
871 | { | |
872 | if (module) { | |
873 | preempt_disable(); | |
874 | smp_wmb(); /* see comment in module_refcount */ | |
875 | __this_cpu_inc(module->refptr->decs); | |
876 | ||
877 | trace_module_put(module, _RET_IP_); | |
878 | /* Maybe they're waiting for us to drop reference? */ | |
879 | if (unlikely(!module_is_live(module))) | |
880 | wake_up_process(module->waiter); | |
881 | preempt_enable(); | |
882 | } | |
883 | } | |
884 | EXPORT_SYMBOL(module_put); | |
885 | ||
886 | #else /* !CONFIG_MODULE_UNLOAD */ | |
887 | static inline void print_unload_info(struct seq_file *m, struct module *mod) | |
888 | { | |
889 | /* We don't know the usage count, or what modules are using. */ | |
890 | seq_printf(m, " - -"); | |
891 | } | |
892 | ||
893 | static inline void module_unload_free(struct module *mod) | |
894 | { | |
895 | } | |
896 | ||
897 | int ref_module(struct module *a, struct module *b) | |
898 | { | |
899 | return strong_try_module_get(b); | |
900 | } | |
901 | EXPORT_SYMBOL_GPL(ref_module); | |
902 | ||
903 | static inline int module_unload_init(struct module *mod) | |
904 | { | |
905 | return 0; | |
906 | } | |
907 | #endif /* CONFIG_MODULE_UNLOAD */ | |
908 | ||
909 | static ssize_t show_initstate(struct module_attribute *mattr, | |
910 | struct module *mod, char *buffer) | |
911 | { | |
912 | const char *state = "unknown"; | |
913 | ||
914 | switch (mod->state) { | |
915 | case MODULE_STATE_LIVE: | |
916 | state = "live"; | |
917 | break; | |
918 | case MODULE_STATE_COMING: | |
919 | state = "coming"; | |
920 | break; | |
921 | case MODULE_STATE_GOING: | |
922 | state = "going"; | |
923 | break; | |
924 | } | |
925 | return sprintf(buffer, "%s\n", state); | |
926 | } | |
927 | ||
928 | static struct module_attribute initstate = { | |
929 | .attr = { .name = "initstate", .mode = 0444 }, | |
930 | .show = show_initstate, | |
931 | }; | |
932 | ||
933 | static struct module_attribute *modinfo_attrs[] = { | |
934 | &modinfo_version, | |
935 | &modinfo_srcversion, | |
936 | &initstate, | |
937 | #ifdef CONFIG_MODULE_UNLOAD | |
938 | &refcnt, | |
939 | #endif | |
940 | NULL, | |
941 | }; | |
942 | ||
943 | static const char vermagic[] = VERMAGIC_STRING; | |
944 | ||
945 | static int try_to_force_load(struct module *mod, const char *reason) | |
946 | { | |
947 | #ifdef CONFIG_MODULE_FORCE_LOAD | |
948 | if (!test_taint(TAINT_FORCED_MODULE)) | |
949 | printk(KERN_WARNING "%s: %s: kernel tainted.\n", | |
950 | mod->name, reason); | |
951 | add_taint_module(mod, TAINT_FORCED_MODULE); | |
952 | return 0; | |
953 | #else | |
954 | return -ENOEXEC; | |
955 | #endif | |
956 | } | |
957 | ||
958 | #ifdef CONFIG_MODVERSIONS | |
959 | /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */ | |
960 | static unsigned long maybe_relocated(unsigned long crc, | |
961 | const struct module *crc_owner) | |
962 | { | |
963 | #ifdef ARCH_RELOCATES_KCRCTAB | |
964 | if (crc_owner == NULL) | |
965 | return crc - (unsigned long)reloc_start; | |
966 | #endif | |
967 | return crc; | |
968 | } | |
969 | ||
970 | static int check_version(Elf_Shdr *sechdrs, | |
971 | unsigned int versindex, | |
972 | const char *symname, | |
973 | struct module *mod, | |
974 | const unsigned long *crc, | |
975 | const struct module *crc_owner) | |
976 | { | |
977 | unsigned int i, num_versions; | |
978 | struct modversion_info *versions; | |
979 | ||
980 | /* Exporting module didn't supply crcs? OK, we're already tainted. */ | |
981 | if (!crc) | |
982 | return 1; | |
983 | ||
984 | /* No versions at all? modprobe --force does this. */ | |
985 | if (versindex == 0) | |
986 | return try_to_force_load(mod, symname) == 0; | |
987 | ||
988 | versions = (void *) sechdrs[versindex].sh_addr; | |
989 | num_versions = sechdrs[versindex].sh_size | |
990 | / sizeof(struct modversion_info); | |
991 | ||
992 | for (i = 0; i < num_versions; i++) { | |
993 | if (strcmp(versions[i].name, symname) != 0) | |
994 | continue; | |
995 | ||
996 | if (versions[i].crc == maybe_relocated(*crc, crc_owner)) | |
997 | return 1; | |
998 | DEBUGP("Found checksum %lX vs module %lX\n", | |
999 | maybe_relocated(*crc, crc_owner), versions[i].crc); | |
1000 | goto bad_version; | |
1001 | } | |
1002 | ||
1003 | printk(KERN_WARNING "%s: no symbol version for %s\n", | |
1004 | mod->name, symname); | |
1005 | return 0; | |
1006 | ||
1007 | bad_version: | |
1008 | printk("%s: disagrees about version of symbol %s\n", | |
1009 | mod->name, symname); | |
1010 | return 0; | |
1011 | } | |
1012 | ||
1013 | static inline int check_modstruct_version(Elf_Shdr *sechdrs, | |
1014 | unsigned int versindex, | |
1015 | struct module *mod) | |
1016 | { | |
1017 | const unsigned long *crc; | |
1018 | ||
1019 | /* Since this should be found in kernel (which can't be removed), | |
1020 | * no locking is necessary. */ | |
1021 | if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL, | |
1022 | &crc, true, false)) | |
1023 | BUG(); | |
1024 | return check_version(sechdrs, versindex, "module_layout", mod, crc, | |
1025 | NULL); | |
1026 | } | |
1027 | ||
1028 | /* First part is kernel version, which we ignore if module has crcs. */ | |
1029 | static inline int same_magic(const char *amagic, const char *bmagic, | |
1030 | bool has_crcs) | |
1031 | { | |
1032 | if (has_crcs) { | |
1033 | amagic += strcspn(amagic, " "); | |
1034 | bmagic += strcspn(bmagic, " "); | |
1035 | } | |
1036 | return strcmp(amagic, bmagic) == 0; | |
1037 | } | |
1038 | #else | |
1039 | static inline int check_version(Elf_Shdr *sechdrs, | |
1040 | unsigned int versindex, | |
1041 | const char *symname, | |
1042 | struct module *mod, | |
1043 | const unsigned long *crc, | |
1044 | const struct module *crc_owner) | |
1045 | { | |
1046 | return 1; | |
1047 | } | |
1048 | ||
1049 | static inline int check_modstruct_version(Elf_Shdr *sechdrs, | |
1050 | unsigned int versindex, | |
1051 | struct module *mod) | |
1052 | { | |
1053 | return 1; | |
1054 | } | |
1055 | ||
1056 | static inline int same_magic(const char *amagic, const char *bmagic, | |
1057 | bool has_crcs) | |
1058 | { | |
1059 | return strcmp(amagic, bmagic) == 0; | |
1060 | } | |
1061 | #endif /* CONFIG_MODVERSIONS */ | |
1062 | ||
1063 | /* Resolve a symbol for this module. I.e. if we find one, record usage. */ | |
1064 | static const struct kernel_symbol *resolve_symbol(struct module *mod, | |
1065 | const struct load_info *info, | |
1066 | const char *name, | |
1067 | char ownername[]) | |
1068 | { | |
1069 | struct module *owner; | |
1070 | const struct kernel_symbol *sym; | |
1071 | const unsigned long *crc; | |
1072 | int err; | |
1073 | ||
1074 | mutex_lock(&module_mutex); | |
1075 | sym = find_symbol(name, &owner, &crc, | |
1076 | !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true); | |
1077 | if (!sym) | |
1078 | goto unlock; | |
1079 | ||
1080 | if (!check_version(info->sechdrs, info->index.vers, name, mod, crc, | |
1081 | owner)) { | |
1082 | sym = ERR_PTR(-EINVAL); | |
1083 | goto getname; | |
1084 | } | |
1085 | ||
1086 | err = ref_module(mod, owner); | |
1087 | if (err) { | |
1088 | sym = ERR_PTR(err); | |
1089 | goto getname; | |
1090 | } | |
1091 | ||
1092 | getname: | |
1093 | /* We must make copy under the lock if we failed to get ref. */ | |
1094 | strncpy(ownername, module_name(owner), MODULE_NAME_LEN); | |
1095 | unlock: | |
1096 | mutex_unlock(&module_mutex); | |
1097 | return sym; | |
1098 | } | |
1099 | ||
1100 | static const struct kernel_symbol * | |
1101 | resolve_symbol_wait(struct module *mod, | |
1102 | const struct load_info *info, | |
1103 | const char *name) | |
1104 | { | |
1105 | const struct kernel_symbol *ksym; | |
1106 | char owner[MODULE_NAME_LEN]; | |
1107 | ||
1108 | if (wait_event_interruptible_timeout(module_wq, | |
1109 | !IS_ERR(ksym = resolve_symbol(mod, info, name, owner)) | |
1110 | || PTR_ERR(ksym) != -EBUSY, | |
1111 | 30 * HZ) <= 0) { | |
1112 | printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n", | |
1113 | mod->name, owner); | |
1114 | } | |
1115 | return ksym; | |
1116 | } | |
1117 | ||
1118 | /* | |
1119 | * /sys/module/foo/sections stuff | |
1120 | * J. Corbet <corbet@lwn.net> | |
1121 | */ | |
1122 | #ifdef CONFIG_SYSFS | |
1123 | ||
1124 | #ifdef CONFIG_KALLSYMS | |
1125 | static inline bool sect_empty(const Elf_Shdr *sect) | |
1126 | { | |
1127 | return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0; | |
1128 | } | |
1129 | ||
1130 | struct module_sect_attr | |
1131 | { | |
1132 | struct module_attribute mattr; | |
1133 | char *name; | |
1134 | unsigned long address; | |
1135 | }; | |
1136 | ||
1137 | struct module_sect_attrs | |
1138 | { | |
1139 | struct attribute_group grp; | |
1140 | unsigned int nsections; | |
1141 | struct module_sect_attr attrs[0]; | |
1142 | }; | |
1143 | ||
1144 | static ssize_t module_sect_show(struct module_attribute *mattr, | |
1145 | struct module *mod, char *buf) | |
1146 | { | |
1147 | struct module_sect_attr *sattr = | |
1148 | container_of(mattr, struct module_sect_attr, mattr); | |
1149 | return sprintf(buf, "0x%lx\n", sattr->address); | |
1150 | } | |
1151 | ||
1152 | static void free_sect_attrs(struct module_sect_attrs *sect_attrs) | |
1153 | { | |
1154 | unsigned int section; | |
1155 | ||
1156 | for (section = 0; section < sect_attrs->nsections; section++) | |
1157 | kfree(sect_attrs->attrs[section].name); | |
1158 | kfree(sect_attrs); | |
1159 | } | |
1160 | ||
1161 | static void add_sect_attrs(struct module *mod, const struct load_info *info) | |
1162 | { | |
1163 | unsigned int nloaded = 0, i, size[2]; | |
1164 | struct module_sect_attrs *sect_attrs; | |
1165 | struct module_sect_attr *sattr; | |
1166 | struct attribute **gattr; | |
1167 | ||
1168 | /* Count loaded sections and allocate structures */ | |
1169 | for (i = 0; i < info->hdr->e_shnum; i++) | |
1170 | if (!sect_empty(&info->sechdrs[i])) | |
1171 | nloaded++; | |
1172 | size[0] = ALIGN(sizeof(*sect_attrs) | |
1173 | + nloaded * sizeof(sect_attrs->attrs[0]), | |
1174 | sizeof(sect_attrs->grp.attrs[0])); | |
1175 | size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]); | |
1176 | sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); | |
1177 | if (sect_attrs == NULL) | |
1178 | return; | |
1179 | ||
1180 | /* Setup section attributes. */ | |
1181 | sect_attrs->grp.name = "sections"; | |
1182 | sect_attrs->grp.attrs = (void *)sect_attrs + size[0]; | |
1183 | ||
1184 | sect_attrs->nsections = 0; | |
1185 | sattr = §_attrs->attrs[0]; | |
1186 | gattr = §_attrs->grp.attrs[0]; | |
1187 | for (i = 0; i < info->hdr->e_shnum; i++) { | |
1188 | Elf_Shdr *sec = &info->sechdrs[i]; | |
1189 | if (sect_empty(sec)) | |
1190 | continue; | |
1191 | sattr->address = sec->sh_addr; | |
1192 | sattr->name = kstrdup(info->secstrings + sec->sh_name, | |
1193 | GFP_KERNEL); | |
1194 | if (sattr->name == NULL) | |
1195 | goto out; | |
1196 | sect_attrs->nsections++; | |
1197 | sysfs_attr_init(&sattr->mattr.attr); | |
1198 | sattr->mattr.show = module_sect_show; | |
1199 | sattr->mattr.store = NULL; | |
1200 | sattr->mattr.attr.name = sattr->name; | |
1201 | sattr->mattr.attr.mode = S_IRUGO; | |
1202 | *(gattr++) = &(sattr++)->mattr.attr; | |
1203 | } | |
1204 | *gattr = NULL; | |
1205 | ||
1206 | if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) | |
1207 | goto out; | |
1208 | ||
1209 | mod->sect_attrs = sect_attrs; | |
1210 | return; | |
1211 | out: | |
1212 | free_sect_attrs(sect_attrs); | |
1213 | } | |
1214 | ||
1215 | static void remove_sect_attrs(struct module *mod) | |
1216 | { | |
1217 | if (mod->sect_attrs) { | |
1218 | sysfs_remove_group(&mod->mkobj.kobj, | |
1219 | &mod->sect_attrs->grp); | |
1220 | /* We are positive that no one is using any sect attrs | |
1221 | * at this point. Deallocate immediately. */ | |
1222 | free_sect_attrs(mod->sect_attrs); | |
1223 | mod->sect_attrs = NULL; | |
1224 | } | |
1225 | } | |
1226 | ||
1227 | /* | |
1228 | * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections. | |
1229 | */ | |
1230 | ||
1231 | struct module_notes_attrs { | |
1232 | struct kobject *dir; | |
1233 | unsigned int notes; | |
1234 | struct bin_attribute attrs[0]; | |
1235 | }; | |
1236 | ||
1237 | static ssize_t module_notes_read(struct file *filp, struct kobject *kobj, | |
1238 | struct bin_attribute *bin_attr, | |
1239 | char *buf, loff_t pos, size_t count) | |
1240 | { | |
1241 | /* | |
1242 | * The caller checked the pos and count against our size. | |
1243 | */ | |
1244 | memcpy(buf, bin_attr->private + pos, count); | |
1245 | return count; | |
1246 | } | |
1247 | ||
1248 | static void free_notes_attrs(struct module_notes_attrs *notes_attrs, | |
1249 | unsigned int i) | |
1250 | { | |
1251 | if (notes_attrs->dir) { | |
1252 | while (i-- > 0) | |
1253 | sysfs_remove_bin_file(notes_attrs->dir, | |
1254 | ¬es_attrs->attrs[i]); | |
1255 | kobject_put(notes_attrs->dir); | |
1256 | } | |
1257 | kfree(notes_attrs); | |
1258 | } | |
1259 | ||
1260 | static void add_notes_attrs(struct module *mod, const struct load_info *info) | |
1261 | { | |
1262 | unsigned int notes, loaded, i; | |
1263 | struct module_notes_attrs *notes_attrs; | |
1264 | struct bin_attribute *nattr; | |
1265 | ||
1266 | /* failed to create section attributes, so can't create notes */ | |
1267 | if (!mod->sect_attrs) | |
1268 | return; | |
1269 | ||
1270 | /* Count notes sections and allocate structures. */ | |
1271 | notes = 0; | |
1272 | for (i = 0; i < info->hdr->e_shnum; i++) | |
1273 | if (!sect_empty(&info->sechdrs[i]) && | |
1274 | (info->sechdrs[i].sh_type == SHT_NOTE)) | |
1275 | ++notes; | |
1276 | ||
1277 | if (notes == 0) | |
1278 | return; | |
1279 | ||
1280 | notes_attrs = kzalloc(sizeof(*notes_attrs) | |
1281 | + notes * sizeof(notes_attrs->attrs[0]), | |
1282 | GFP_KERNEL); | |
1283 | if (notes_attrs == NULL) | |
1284 | return; | |
1285 | ||
1286 | notes_attrs->notes = notes; | |
1287 | nattr = ¬es_attrs->attrs[0]; | |
1288 | for (loaded = i = 0; i < info->hdr->e_shnum; ++i) { | |
1289 | if (sect_empty(&info->sechdrs[i])) | |
1290 | continue; | |
1291 | if (info->sechdrs[i].sh_type == SHT_NOTE) { | |
1292 | sysfs_bin_attr_init(nattr); | |
1293 | nattr->attr.name = mod->sect_attrs->attrs[loaded].name; | |
1294 | nattr->attr.mode = S_IRUGO; | |
1295 | nattr->size = info->sechdrs[i].sh_size; | |
1296 | nattr->private = (void *) info->sechdrs[i].sh_addr; | |
1297 | nattr->read = module_notes_read; | |
1298 | ++nattr; | |
1299 | } | |
1300 | ++loaded; | |
1301 | } | |
1302 | ||
1303 | notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); | |
1304 | if (!notes_attrs->dir) | |
1305 | goto out; | |
1306 | ||
1307 | for (i = 0; i < notes; ++i) | |
1308 | if (sysfs_create_bin_file(notes_attrs->dir, | |
1309 | ¬es_attrs->attrs[i])) | |
1310 | goto out; | |
1311 | ||
1312 | mod->notes_attrs = notes_attrs; | |
1313 | return; | |
1314 | ||
1315 | out: | |
1316 | free_notes_attrs(notes_attrs, i); | |
1317 | } | |
1318 | ||
1319 | static void remove_notes_attrs(struct module *mod) | |
1320 | { | |
1321 | if (mod->notes_attrs) | |
1322 | free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes); | |
1323 | } | |
1324 | ||
1325 | #else | |
1326 | ||
1327 | static inline void add_sect_attrs(struct module *mod, | |
1328 | const struct load_info *info) | |
1329 | { | |
1330 | } | |
1331 | ||
1332 | static inline void remove_sect_attrs(struct module *mod) | |
1333 | { | |
1334 | } | |
1335 | ||
1336 | static inline void add_notes_attrs(struct module *mod, | |
1337 | const struct load_info *info) | |
1338 | { | |
1339 | } | |
1340 | ||
1341 | static inline void remove_notes_attrs(struct module *mod) | |
1342 | { | |
1343 | } | |
1344 | #endif /* CONFIG_KALLSYMS */ | |
1345 | ||
1346 | static void add_usage_links(struct module *mod) | |
1347 | { | |
1348 | #ifdef CONFIG_MODULE_UNLOAD | |
1349 | struct module_use *use; | |
1350 | int nowarn; | |
1351 | ||
1352 | mutex_lock(&module_mutex); | |
1353 | list_for_each_entry(use, &mod->target_list, target_list) { | |
1354 | nowarn = sysfs_create_link(use->target->holders_dir, | |
1355 | &mod->mkobj.kobj, mod->name); | |
1356 | } | |
1357 | mutex_unlock(&module_mutex); | |
1358 | #endif | |
1359 | } | |
1360 | ||
1361 | static void del_usage_links(struct module *mod) | |
1362 | { | |
1363 | #ifdef CONFIG_MODULE_UNLOAD | |
1364 | struct module_use *use; | |
1365 | ||
1366 | mutex_lock(&module_mutex); | |
1367 | list_for_each_entry(use, &mod->target_list, target_list) | |
1368 | sysfs_remove_link(use->target->holders_dir, mod->name); | |
1369 | mutex_unlock(&module_mutex); | |
1370 | #endif | |
1371 | } | |
1372 | ||
1373 | static int module_add_modinfo_attrs(struct module *mod) | |
1374 | { | |
1375 | struct module_attribute *attr; | |
1376 | struct module_attribute *temp_attr; | |
1377 | int error = 0; | |
1378 | int i; | |
1379 | ||
1380 | mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * | |
1381 | (ARRAY_SIZE(modinfo_attrs) + 1)), | |
1382 | GFP_KERNEL); | |
1383 | if (!mod->modinfo_attrs) | |
1384 | return -ENOMEM; | |
1385 | ||
1386 | temp_attr = mod->modinfo_attrs; | |
1387 | for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) { | |
1388 | if (!attr->test || | |
1389 | (attr->test && attr->test(mod))) { | |
1390 | memcpy(temp_attr, attr, sizeof(*temp_attr)); | |
1391 | sysfs_attr_init(&temp_attr->attr); | |
1392 | error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr); | |
1393 | ++temp_attr; | |
1394 | } | |
1395 | } | |
1396 | return error; | |
1397 | } | |
1398 | ||
1399 | static void module_remove_modinfo_attrs(struct module *mod) | |
1400 | { | |
1401 | struct module_attribute *attr; | |
1402 | int i; | |
1403 | ||
1404 | for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { | |
1405 | /* pick a field to test for end of list */ | |
1406 | if (!attr->attr.name) | |
1407 | break; | |
1408 | sysfs_remove_file(&mod->mkobj.kobj,&attr->attr); | |
1409 | if (attr->free) | |
1410 | attr->free(mod); | |
1411 | } | |
1412 | kfree(mod->modinfo_attrs); | |
1413 | } | |
1414 | ||
1415 | static int mod_sysfs_init(struct module *mod) | |
1416 | { | |
1417 | int err; | |
1418 | struct kobject *kobj; | |
1419 | ||
1420 | if (!module_sysfs_initialized) { | |
1421 | printk(KERN_ERR "%s: module sysfs not initialized\n", | |
1422 | mod->name); | |
1423 | err = -EINVAL; | |
1424 | goto out; | |
1425 | } | |
1426 | ||
1427 | kobj = kset_find_obj(module_kset, mod->name); | |
1428 | if (kobj) { | |
1429 | printk(KERN_ERR "%s: module is already loaded\n", mod->name); | |
1430 | kobject_put(kobj); | |
1431 | err = -EINVAL; | |
1432 | goto out; | |
1433 | } | |
1434 | ||
1435 | mod->mkobj.mod = mod; | |
1436 | ||
1437 | memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); | |
1438 | mod->mkobj.kobj.kset = module_kset; | |
1439 | err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, | |
1440 | "%s", mod->name); | |
1441 | if (err) | |
1442 | kobject_put(&mod->mkobj.kobj); | |
1443 | ||
1444 | /* delay uevent until full sysfs population */ | |
1445 | out: | |
1446 | return err; | |
1447 | } | |
1448 | ||
1449 | static int mod_sysfs_setup(struct module *mod, | |
1450 | const struct load_info *info, | |
1451 | struct kernel_param *kparam, | |
1452 | unsigned int num_params) | |
1453 | { | |
1454 | int err; | |
1455 | ||
1456 | err = mod_sysfs_init(mod); | |
1457 | if (err) | |
1458 | goto out; | |
1459 | ||
1460 | mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); | |
1461 | if (!mod->holders_dir) { | |
1462 | err = -ENOMEM; | |
1463 | goto out_unreg; | |
1464 | } | |
1465 | ||
1466 | err = module_param_sysfs_setup(mod, kparam, num_params); | |
1467 | if (err) | |
1468 | goto out_unreg_holders; | |
1469 | ||
1470 | err = module_add_modinfo_attrs(mod); | |
1471 | if (err) | |
1472 | goto out_unreg_param; | |
1473 | ||
1474 | add_usage_links(mod); | |
1475 | add_sect_attrs(mod, info); | |
1476 | add_notes_attrs(mod, info); | |
1477 | ||
1478 | kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD); | |
1479 | return 0; | |
1480 | ||
1481 | out_unreg_param: | |
1482 | module_param_sysfs_remove(mod); | |
1483 | out_unreg_holders: | |
1484 | kobject_put(mod->holders_dir); | |
1485 | out_unreg: | |
1486 | kobject_put(&mod->mkobj.kobj); | |
1487 | out: | |
1488 | return err; | |
1489 | } | |
1490 | ||
1491 | static void mod_sysfs_fini(struct module *mod) | |
1492 | { | |
1493 | remove_notes_attrs(mod); | |
1494 | remove_sect_attrs(mod); | |
1495 | kobject_put(&mod->mkobj.kobj); | |
1496 | } | |
1497 | ||
1498 | #else /* !CONFIG_SYSFS */ | |
1499 | ||
1500 | static int mod_sysfs_setup(struct module *mod, | |
1501 | const struct load_info *info, | |
1502 | struct kernel_param *kparam, | |
1503 | unsigned int num_params) | |
1504 | { | |
1505 | return 0; | |
1506 | } | |
1507 | ||
1508 | static void mod_sysfs_fini(struct module *mod) | |
1509 | { | |
1510 | } | |
1511 | ||
1512 | static void module_remove_modinfo_attrs(struct module *mod) | |
1513 | { | |
1514 | } | |
1515 | ||
1516 | static void del_usage_links(struct module *mod) | |
1517 | { | |
1518 | } | |
1519 | ||
1520 | #endif /* CONFIG_SYSFS */ | |
1521 | ||
1522 | static void mod_sysfs_teardown(struct module *mod) | |
1523 | { | |
1524 | del_usage_links(mod); | |
1525 | module_remove_modinfo_attrs(mod); | |
1526 | module_param_sysfs_remove(mod); | |
1527 | kobject_put(mod->mkobj.drivers_dir); | |
1528 | kobject_put(mod->holders_dir); | |
1529 | mod_sysfs_fini(mod); | |
1530 | } | |
1531 | ||
1532 | /* | |
1533 | * unlink the module with the whole machine is stopped with interrupts off | |
1534 | * - this defends against kallsyms not taking locks | |
1535 | */ | |
1536 | static int __unlink_module(void *_mod) | |
1537 | { | |
1538 | struct module *mod = _mod; | |
1539 | list_del(&mod->list); | |
1540 | return 0; | |
1541 | } | |
1542 | ||
1543 | /* Free a module, remove from lists, etc. */ | |
1544 | static void free_module(struct module *mod) | |
1545 | { | |
1546 | trace_module_free(mod); | |
1547 | ||
1548 | /* Delete from various lists */ | |
1549 | mutex_lock(&module_mutex); | |
1550 | stop_machine(__unlink_module, mod, NULL); | |
1551 | mutex_unlock(&module_mutex); | |
1552 | mod_sysfs_teardown(mod); | |
1553 | ||
1554 | /* Remove dynamic debug info */ | |
1555 | ddebug_remove_module(mod->name); | |
1556 | ||
1557 | /* Arch-specific cleanup. */ | |
1558 | module_arch_cleanup(mod); | |
1559 | ||
1560 | /* Module unload stuff */ | |
1561 | module_unload_free(mod); | |
1562 | ||
1563 | /* Free any allocated parameters. */ | |
1564 | destroy_params(mod->kp, mod->num_kp); | |
1565 | ||
1566 | /* This may be NULL, but that's OK */ | |
1567 | module_free(mod, mod->module_init); | |
1568 | kfree(mod->args); | |
1569 | percpu_modfree(mod); | |
1570 | ||
1571 | /* Free lock-classes: */ | |
1572 | lockdep_free_key_range(mod->module_core, mod->core_size); | |
1573 | ||
1574 | /* Finally, free the core (containing the module structure) */ | |
1575 | module_free(mod, mod->module_core); | |
1576 | ||
1577 | #ifdef CONFIG_MPU | |
1578 | update_protections(current->mm); | |
1579 | #endif | |
1580 | } | |
1581 | ||
1582 | void *__symbol_get(const char *symbol) | |
1583 | { | |
1584 | struct module *owner; | |
1585 | const struct kernel_symbol *sym; | |
1586 | ||
1587 | preempt_disable(); | |
1588 | sym = find_symbol(symbol, &owner, NULL, true, true); | |
1589 | if (sym && strong_try_module_get(owner)) | |
1590 | sym = NULL; | |
1591 | preempt_enable(); | |
1592 | ||
1593 | return sym ? (void *)sym->value : NULL; | |
1594 | } | |
1595 | EXPORT_SYMBOL_GPL(__symbol_get); | |
1596 | ||
1597 | /* | |
1598 | * Ensure that an exported symbol [global namespace] does not already exist | |
1599 | * in the kernel or in some other module's exported symbol table. | |
1600 | * | |
1601 | * You must hold the module_mutex. | |
1602 | */ | |
1603 | static int verify_export_symbols(struct module *mod) | |
1604 | { | |
1605 | unsigned int i; | |
1606 | struct module *owner; | |
1607 | const struct kernel_symbol *s; | |
1608 | struct { | |
1609 | const struct kernel_symbol *sym; | |
1610 | unsigned int num; | |
1611 | } arr[] = { | |
1612 | { mod->syms, mod->num_syms }, | |
1613 | { mod->gpl_syms, mod->num_gpl_syms }, | |
1614 | { mod->gpl_future_syms, mod->num_gpl_future_syms }, | |
1615 | #ifdef CONFIG_UNUSED_SYMBOLS | |
1616 | { mod->unused_syms, mod->num_unused_syms }, | |
1617 | { mod->unused_gpl_syms, mod->num_unused_gpl_syms }, | |
1618 | #endif | |
1619 | }; | |
1620 | ||
1621 | for (i = 0; i < ARRAY_SIZE(arr); i++) { | |
1622 | for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) { | |
1623 | if (find_symbol(s->name, &owner, NULL, true, false)) { | |
1624 | printk(KERN_ERR | |
1625 | "%s: exports duplicate symbol %s" | |
1626 | " (owned by %s)\n", | |
1627 | mod->name, s->name, module_name(owner)); | |
1628 | return -ENOEXEC; | |
1629 | } | |
1630 | } | |
1631 | } | |
1632 | return 0; | |
1633 | } | |
1634 | ||
1635 | /* Change all symbols so that st_value encodes the pointer directly. */ | |
1636 | static int simplify_symbols(struct module *mod, const struct load_info *info) | |
1637 | { | |
1638 | Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; | |
1639 | Elf_Sym *sym = (void *)symsec->sh_addr; | |
1640 | unsigned long secbase; | |
1641 | unsigned int i; | |
1642 | int ret = 0; | |
1643 | const struct kernel_symbol *ksym; | |
1644 | ||
1645 | for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) { | |
1646 | const char *name = info->strtab + sym[i].st_name; | |
1647 | ||
1648 | switch (sym[i].st_shndx) { | |
1649 | case SHN_COMMON: | |
1650 | /* We compiled with -fno-common. These are not | |
1651 | supposed to happen. */ | |
1652 | DEBUGP("Common symbol: %s\n", name); | |
1653 | printk("%s: please compile with -fno-common\n", | |
1654 | mod->name); | |
1655 | ret = -ENOEXEC; | |
1656 | break; | |
1657 | ||
1658 | case SHN_ABS: | |
1659 | /* Don't need to do anything */ | |
1660 | DEBUGP("Absolute symbol: 0x%08lx\n", | |
1661 | (long)sym[i].st_value); | |
1662 | break; | |
1663 | ||
1664 | case SHN_UNDEF: | |
1665 | ksym = resolve_symbol_wait(mod, info, name); | |
1666 | /* Ok if resolved. */ | |
1667 | if (ksym && !IS_ERR(ksym)) { | |
1668 | sym[i].st_value = ksym->value; | |
1669 | break; | |
1670 | } | |
1671 | ||
1672 | /* Ok if weak. */ | |
1673 | if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK) | |
1674 | break; | |
1675 | ||
1676 | printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n", | |
1677 | mod->name, name, PTR_ERR(ksym)); | |
1678 | ret = PTR_ERR(ksym) ?: -ENOENT; | |
1679 | break; | |
1680 | ||
1681 | default: | |
1682 | /* Divert to percpu allocation if a percpu var. */ | |
1683 | if (sym[i].st_shndx == info->index.pcpu) | |
1684 | secbase = (unsigned long)mod_percpu(mod); | |
1685 | else | |
1686 | secbase = info->sechdrs[sym[i].st_shndx].sh_addr; | |
1687 | sym[i].st_value += secbase; | |
1688 | break; | |
1689 | } | |
1690 | } | |
1691 | ||
1692 | return ret; | |
1693 | } | |
1694 | ||
1695 | static int apply_relocations(struct module *mod, const struct load_info *info) | |
1696 | { | |
1697 | unsigned int i; | |
1698 | int err = 0; | |
1699 | ||
1700 | /* Now do relocations. */ | |
1701 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
1702 | unsigned int infosec = info->sechdrs[i].sh_info; | |
1703 | ||
1704 | /* Not a valid relocation section? */ | |
1705 | if (infosec >= info->hdr->e_shnum) | |
1706 | continue; | |
1707 | ||
1708 | /* Don't bother with non-allocated sections */ | |
1709 | if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC)) | |
1710 | continue; | |
1711 | ||
1712 | if (info->sechdrs[i].sh_type == SHT_REL) | |
1713 | err = apply_relocate(info->sechdrs, info->strtab, | |
1714 | info->index.sym, i, mod); | |
1715 | else if (info->sechdrs[i].sh_type == SHT_RELA) | |
1716 | err = apply_relocate_add(info->sechdrs, info->strtab, | |
1717 | info->index.sym, i, mod); | |
1718 | if (err < 0) | |
1719 | break; | |
1720 | } | |
1721 | return err; | |
1722 | } | |
1723 | ||
1724 | /* Additional bytes needed by arch in front of individual sections */ | |
1725 | unsigned int __weak arch_mod_section_prepend(struct module *mod, | |
1726 | unsigned int section) | |
1727 | { | |
1728 | /* default implementation just returns zero */ | |
1729 | return 0; | |
1730 | } | |
1731 | ||
1732 | /* Update size with this section: return offset. */ | |
1733 | static long get_offset(struct module *mod, unsigned int *size, | |
1734 | Elf_Shdr *sechdr, unsigned int section) | |
1735 | { | |
1736 | long ret; | |
1737 | ||
1738 | *size += arch_mod_section_prepend(mod, section); | |
1739 | ret = ALIGN(*size, sechdr->sh_addralign ?: 1); | |
1740 | *size = ret + sechdr->sh_size; | |
1741 | return ret; | |
1742 | } | |
1743 | ||
1744 | /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld | |
1745 | might -- code, read-only data, read-write data, small data. Tally | |
1746 | sizes, and place the offsets into sh_entsize fields: high bit means it | |
1747 | belongs in init. */ | |
1748 | static void layout_sections(struct module *mod, struct load_info *info) | |
1749 | { | |
1750 | static unsigned long const masks[][2] = { | |
1751 | /* NOTE: all executable code must be the first section | |
1752 | * in this array; otherwise modify the text_size | |
1753 | * finder in the two loops below */ | |
1754 | { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL }, | |
1755 | { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL }, | |
1756 | { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL }, | |
1757 | { ARCH_SHF_SMALL | SHF_ALLOC, 0 } | |
1758 | }; | |
1759 | unsigned int m, i; | |
1760 | ||
1761 | for (i = 0; i < info->hdr->e_shnum; i++) | |
1762 | info->sechdrs[i].sh_entsize = ~0UL; | |
1763 | ||
1764 | DEBUGP("Core section allocation order:\n"); | |
1765 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { | |
1766 | for (i = 0; i < info->hdr->e_shnum; ++i) { | |
1767 | Elf_Shdr *s = &info->sechdrs[i]; | |
1768 | const char *sname = info->secstrings + s->sh_name; | |
1769 | ||
1770 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
1771 | || (s->sh_flags & masks[m][1]) | |
1772 | || s->sh_entsize != ~0UL | |
1773 | || strstarts(sname, ".init")) | |
1774 | continue; | |
1775 | s->sh_entsize = get_offset(mod, &mod->core_size, s, i); | |
1776 | DEBUGP("\t%s\n", name); | |
1777 | } | |
1778 | if (m == 0) | |
1779 | mod->core_text_size = mod->core_size; | |
1780 | } | |
1781 | ||
1782 | DEBUGP("Init section allocation order:\n"); | |
1783 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { | |
1784 | for (i = 0; i < info->hdr->e_shnum; ++i) { | |
1785 | Elf_Shdr *s = &info->sechdrs[i]; | |
1786 | const char *sname = info->secstrings + s->sh_name; | |
1787 | ||
1788 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
1789 | || (s->sh_flags & masks[m][1]) | |
1790 | || s->sh_entsize != ~0UL | |
1791 | || !strstarts(sname, ".init")) | |
1792 | continue; | |
1793 | s->sh_entsize = (get_offset(mod, &mod->init_size, s, i) | |
1794 | | INIT_OFFSET_MASK); | |
1795 | DEBUGP("\t%s\n", sname); | |
1796 | } | |
1797 | if (m == 0) | |
1798 | mod->init_text_size = mod->init_size; | |
1799 | } | |
1800 | } | |
1801 | ||
1802 | static void set_license(struct module *mod, const char *license) | |
1803 | { | |
1804 | if (!license) | |
1805 | license = "unspecified"; | |
1806 | ||
1807 | if (!license_is_gpl_compatible(license)) { | |
1808 | if (!test_taint(TAINT_PROPRIETARY_MODULE)) | |
1809 | printk(KERN_WARNING "%s: module license '%s' taints " | |
1810 | "kernel.\n", mod->name, license); | |
1811 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE); | |
1812 | } | |
1813 | } | |
1814 | ||
1815 | /* Parse tag=value strings from .modinfo section */ | |
1816 | static char *next_string(char *string, unsigned long *secsize) | |
1817 | { | |
1818 | /* Skip non-zero chars */ | |
1819 | while (string[0]) { | |
1820 | string++; | |
1821 | if ((*secsize)-- <= 1) | |
1822 | return NULL; | |
1823 | } | |
1824 | ||
1825 | /* Skip any zero padding. */ | |
1826 | while (!string[0]) { | |
1827 | string++; | |
1828 | if ((*secsize)-- <= 1) | |
1829 | return NULL; | |
1830 | } | |
1831 | return string; | |
1832 | } | |
1833 | ||
1834 | static char *get_modinfo(struct load_info *info, const char *tag) | |
1835 | { | |
1836 | char *p; | |
1837 | unsigned int taglen = strlen(tag); | |
1838 | Elf_Shdr *infosec = &info->sechdrs[info->index.info]; | |
1839 | unsigned long size = infosec->sh_size; | |
1840 | ||
1841 | for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) { | |
1842 | if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') | |
1843 | return p + taglen + 1; | |
1844 | } | |
1845 | return NULL; | |
1846 | } | |
1847 | ||
1848 | static void setup_modinfo(struct module *mod, struct load_info *info) | |
1849 | { | |
1850 | struct module_attribute *attr; | |
1851 | int i; | |
1852 | ||
1853 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
1854 | if (attr->setup) | |
1855 | attr->setup(mod, get_modinfo(info, attr->attr.name)); | |
1856 | } | |
1857 | } | |
1858 | ||
1859 | static void free_modinfo(struct module *mod) | |
1860 | { | |
1861 | struct module_attribute *attr; | |
1862 | int i; | |
1863 | ||
1864 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
1865 | if (attr->free) | |
1866 | attr->free(mod); | |
1867 | } | |
1868 | } | |
1869 | ||
1870 | #ifdef CONFIG_KALLSYMS | |
1871 | ||
1872 | /* lookup symbol in given range of kernel_symbols */ | |
1873 | static const struct kernel_symbol *lookup_symbol(const char *name, | |
1874 | const struct kernel_symbol *start, | |
1875 | const struct kernel_symbol *stop) | |
1876 | { | |
1877 | const struct kernel_symbol *ks = start; | |
1878 | for (; ks < stop; ks++) | |
1879 | if (strcmp(ks->name, name) == 0) | |
1880 | return ks; | |
1881 | return NULL; | |
1882 | } | |
1883 | ||
1884 | static int is_exported(const char *name, unsigned long value, | |
1885 | const struct module *mod) | |
1886 | { | |
1887 | const struct kernel_symbol *ks; | |
1888 | if (!mod) | |
1889 | ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab); | |
1890 | else | |
1891 | ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms); | |
1892 | return ks != NULL && ks->value == value; | |
1893 | } | |
1894 | ||
1895 | /* As per nm */ | |
1896 | static char elf_type(const Elf_Sym *sym, const struct load_info *info) | |
1897 | { | |
1898 | const Elf_Shdr *sechdrs = info->sechdrs; | |
1899 | ||
1900 | if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { | |
1901 | if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) | |
1902 | return 'v'; | |
1903 | else | |
1904 | return 'w'; | |
1905 | } | |
1906 | if (sym->st_shndx == SHN_UNDEF) | |
1907 | return 'U'; | |
1908 | if (sym->st_shndx == SHN_ABS) | |
1909 | return 'a'; | |
1910 | if (sym->st_shndx >= SHN_LORESERVE) | |
1911 | return '?'; | |
1912 | if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) | |
1913 | return 't'; | |
1914 | if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC | |
1915 | && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { | |
1916 | if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) | |
1917 | return 'r'; | |
1918 | else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
1919 | return 'g'; | |
1920 | else | |
1921 | return 'd'; | |
1922 | } | |
1923 | if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { | |
1924 | if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
1925 | return 's'; | |
1926 | else | |
1927 | return 'b'; | |
1928 | } | |
1929 | if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name, | |
1930 | ".debug")) { | |
1931 | return 'n'; | |
1932 | } | |
1933 | return '?'; | |
1934 | } | |
1935 | ||
1936 | static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs, | |
1937 | unsigned int shnum) | |
1938 | { | |
1939 | const Elf_Shdr *sec; | |
1940 | ||
1941 | if (src->st_shndx == SHN_UNDEF | |
1942 | || src->st_shndx >= shnum | |
1943 | || !src->st_name) | |
1944 | return false; | |
1945 | ||
1946 | sec = sechdrs + src->st_shndx; | |
1947 | if (!(sec->sh_flags & SHF_ALLOC) | |
1948 | #ifndef CONFIG_KALLSYMS_ALL | |
1949 | || !(sec->sh_flags & SHF_EXECINSTR) | |
1950 | #endif | |
1951 | || (sec->sh_entsize & INIT_OFFSET_MASK)) | |
1952 | return false; | |
1953 | ||
1954 | return true; | |
1955 | } | |
1956 | ||
1957 | static void layout_symtab(struct module *mod, struct load_info *info) | |
1958 | { | |
1959 | Elf_Shdr *symsect = info->sechdrs + info->index.sym; | |
1960 | Elf_Shdr *strsect = info->sechdrs + info->index.str; | |
1961 | const Elf_Sym *src; | |
1962 | unsigned int i, nsrc, ndst; | |
1963 | ||
1964 | /* Put symbol section at end of init part of module. */ | |
1965 | symsect->sh_flags |= SHF_ALLOC; | |
1966 | symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect, | |
1967 | info->index.sym) | INIT_OFFSET_MASK; | |
1968 | DEBUGP("\t%s\n", info->secstrings + symsect->sh_name); | |
1969 | ||
1970 | src = (void *)info->hdr + symsect->sh_offset; | |
1971 | nsrc = symsect->sh_size / sizeof(*src); | |
1972 | for (ndst = i = 1; i < nsrc; ++i, ++src) | |
1973 | if (is_core_symbol(src, info->sechdrs, info->hdr->e_shnum)) { | |
1974 | unsigned int j = src->st_name; | |
1975 | ||
1976 | while (!__test_and_set_bit(j, info->strmap) | |
1977 | && info->strtab[j]) | |
1978 | ++j; | |
1979 | ++ndst; | |
1980 | } | |
1981 | ||
1982 | /* Append room for core symbols at end of core part. */ | |
1983 | info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1); | |
1984 | mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym); | |
1985 | ||
1986 | /* Put string table section at end of init part of module. */ | |
1987 | strsect->sh_flags |= SHF_ALLOC; | |
1988 | strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect, | |
1989 | info->index.str) | INIT_OFFSET_MASK; | |
1990 | DEBUGP("\t%s\n", info->secstrings + strsect->sh_name); | |
1991 | ||
1992 | /* Append room for core symbols' strings at end of core part. */ | |
1993 | info->stroffs = mod->core_size; | |
1994 | __set_bit(0, info->strmap); | |
1995 | mod->core_size += bitmap_weight(info->strmap, strsect->sh_size); | |
1996 | } | |
1997 | ||
1998 | static void add_kallsyms(struct module *mod, const struct load_info *info) | |
1999 | { | |
2000 | unsigned int i, ndst; | |
2001 | const Elf_Sym *src; | |
2002 | Elf_Sym *dst; | |
2003 | char *s; | |
2004 | Elf_Shdr *symsec = &info->sechdrs[info->index.sym]; | |
2005 | ||
2006 | mod->symtab = (void *)symsec->sh_addr; | |
2007 | mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym); | |
2008 | /* Make sure we get permanent strtab: don't use info->strtab. */ | |
2009 | mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr; | |
2010 | ||
2011 | /* Set types up while we still have access to sections. */ | |
2012 | for (i = 0; i < mod->num_symtab; i++) | |
2013 | mod->symtab[i].st_info = elf_type(&mod->symtab[i], info); | |
2014 | ||
2015 | mod->core_symtab = dst = mod->module_core + info->symoffs; | |
2016 | src = mod->symtab; | |
2017 | *dst = *src; | |
2018 | for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) { | |
2019 | if (!is_core_symbol(src, info->sechdrs, info->hdr->e_shnum)) | |
2020 | continue; | |
2021 | dst[ndst] = *src; | |
2022 | dst[ndst].st_name = bitmap_weight(info->strmap, | |
2023 | dst[ndst].st_name); | |
2024 | ++ndst; | |
2025 | } | |
2026 | mod->core_num_syms = ndst; | |
2027 | ||
2028 | mod->core_strtab = s = mod->module_core + info->stroffs; | |
2029 | for (*s = 0, i = 1; i < info->sechdrs[info->index.str].sh_size; ++i) | |
2030 | if (test_bit(i, info->strmap)) | |
2031 | *++s = mod->strtab[i]; | |
2032 | } | |
2033 | #else | |
2034 | static inline void layout_symtab(struct module *mod, struct load_info *info) | |
2035 | { | |
2036 | } | |
2037 | ||
2038 | static void add_kallsyms(struct module *mod, struct load_info *info) | |
2039 | { | |
2040 | } | |
2041 | #endif /* CONFIG_KALLSYMS */ | |
2042 | ||
2043 | static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num) | |
2044 | { | |
2045 | if (!debug) | |
2046 | return; | |
2047 | #ifdef CONFIG_DYNAMIC_DEBUG | |
2048 | if (ddebug_add_module(debug, num, debug->modname)) | |
2049 | printk(KERN_ERR "dynamic debug error adding module: %s\n", | |
2050 | debug->modname); | |
2051 | #endif | |
2052 | } | |
2053 | ||
2054 | static void dynamic_debug_remove(struct _ddebug *debug) | |
2055 | { | |
2056 | if (debug) | |
2057 | ddebug_remove_module(debug->modname); | |
2058 | } | |
2059 | ||
2060 | static void *module_alloc_update_bounds(unsigned long size) | |
2061 | { | |
2062 | void *ret = module_alloc(size); | |
2063 | ||
2064 | if (ret) { | |
2065 | mutex_lock(&module_mutex); | |
2066 | /* Update module bounds. */ | |
2067 | if ((unsigned long)ret < module_addr_min) | |
2068 | module_addr_min = (unsigned long)ret; | |
2069 | if ((unsigned long)ret + size > module_addr_max) | |
2070 | module_addr_max = (unsigned long)ret + size; | |
2071 | mutex_unlock(&module_mutex); | |
2072 | } | |
2073 | return ret; | |
2074 | } | |
2075 | ||
2076 | #ifdef CONFIG_DEBUG_KMEMLEAK | |
2077 | static void kmemleak_load_module(const struct module *mod, | |
2078 | const struct load_info *info) | |
2079 | { | |
2080 | unsigned int i; | |
2081 | ||
2082 | /* only scan the sections containing data */ | |
2083 | kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL); | |
2084 | ||
2085 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
2086 | const char *name = info->secstrings + info->sechdrs[i].sh_name; | |
2087 | if (!(info->sechdrs[i].sh_flags & SHF_ALLOC)) | |
2088 | continue; | |
2089 | if (!strstarts(name, ".data") && !strstarts(name, ".bss")) | |
2090 | continue; | |
2091 | ||
2092 | kmemleak_scan_area((void *)info->sechdrs[i].sh_addr, | |
2093 | info->sechdrs[i].sh_size, GFP_KERNEL); | |
2094 | } | |
2095 | } | |
2096 | #else | |
2097 | static inline void kmemleak_load_module(const struct module *mod, | |
2098 | const struct load_info *info) | |
2099 | { | |
2100 | } | |
2101 | #endif | |
2102 | ||
2103 | /* Sets info->hdr and info->len. */ | |
2104 | static int copy_and_check(struct load_info *info, | |
2105 | const void __user *umod, unsigned long len, | |
2106 | const char __user *uargs) | |
2107 | { | |
2108 | int err; | |
2109 | Elf_Ehdr *hdr; | |
2110 | ||
2111 | if (len < sizeof(*hdr)) | |
2112 | return -ENOEXEC; | |
2113 | ||
2114 | /* Suck in entire file: we'll want most of it. */ | |
2115 | /* vmalloc barfs on "unusual" numbers. Check here */ | |
2116 | if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL) | |
2117 | return -ENOMEM; | |
2118 | ||
2119 | if (copy_from_user(hdr, umod, len) != 0) { | |
2120 | err = -EFAULT; | |
2121 | goto free_hdr; | |
2122 | } | |
2123 | ||
2124 | /* Sanity checks against insmoding binaries or wrong arch, | |
2125 | weird elf version */ | |
2126 | if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0 | |
2127 | || hdr->e_type != ET_REL | |
2128 | || !elf_check_arch(hdr) | |
2129 | || hdr->e_shentsize != sizeof(Elf_Shdr)) { | |
2130 | err = -ENOEXEC; | |
2131 | goto free_hdr; | |
2132 | } | |
2133 | ||
2134 | if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) { | |
2135 | err = -ENOEXEC; | |
2136 | goto free_hdr; | |
2137 | } | |
2138 | ||
2139 | info->hdr = hdr; | |
2140 | info->len = len; | |
2141 | return 0; | |
2142 | ||
2143 | free_hdr: | |
2144 | vfree(hdr); | |
2145 | return err; | |
2146 | } | |
2147 | ||
2148 | static void free_copy(struct load_info *info) | |
2149 | { | |
2150 | vfree(info->hdr); | |
2151 | } | |
2152 | ||
2153 | static int rewrite_section_headers(struct load_info *info) | |
2154 | { | |
2155 | unsigned int i; | |
2156 | ||
2157 | /* This should always be true, but let's be sure. */ | |
2158 | info->sechdrs[0].sh_addr = 0; | |
2159 | ||
2160 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
2161 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
2162 | if (shdr->sh_type != SHT_NOBITS | |
2163 | && info->len < shdr->sh_offset + shdr->sh_size) { | |
2164 | printk(KERN_ERR "Module len %lu truncated\n", | |
2165 | info->len); | |
2166 | return -ENOEXEC; | |
2167 | } | |
2168 | ||
2169 | /* Mark all sections sh_addr with their address in the | |
2170 | temporary image. */ | |
2171 | shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset; | |
2172 | ||
2173 | #ifndef CONFIG_MODULE_UNLOAD | |
2174 | /* Don't load .exit sections */ | |
2175 | if (strstarts(info->secstrings+shdr->sh_name, ".exit")) | |
2176 | shdr->sh_flags &= ~(unsigned long)SHF_ALLOC; | |
2177 | #endif | |
2178 | } | |
2179 | ||
2180 | /* Track but don't keep modinfo and version sections. */ | |
2181 | info->index.vers = find_sec(info, "__versions"); | |
2182 | info->index.info = find_sec(info, ".modinfo"); | |
2183 | info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
2184 | info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
2185 | return 0; | |
2186 | } | |
2187 | ||
2188 | /* | |
2189 | * Set up our basic convenience variables (pointers to section headers, | |
2190 | * search for module section index etc), and do some basic section | |
2191 | * verification. | |
2192 | * | |
2193 | * Return the temporary module pointer (we'll replace it with the final | |
2194 | * one when we move the module sections around). | |
2195 | */ | |
2196 | static struct module *setup_load_info(struct load_info *info) | |
2197 | { | |
2198 | unsigned int i; | |
2199 | int err; | |
2200 | struct module *mod; | |
2201 | ||
2202 | /* Set up the convenience variables */ | |
2203 | info->sechdrs = (void *)info->hdr + info->hdr->e_shoff; | |
2204 | info->secstrings = (void *)info->hdr | |
2205 | + info->sechdrs[info->hdr->e_shstrndx].sh_offset; | |
2206 | ||
2207 | err = rewrite_section_headers(info); | |
2208 | if (err) | |
2209 | return ERR_PTR(err); | |
2210 | ||
2211 | /* Find internal symbols and strings. */ | |
2212 | for (i = 1; i < info->hdr->e_shnum; i++) { | |
2213 | if (info->sechdrs[i].sh_type == SHT_SYMTAB) { | |
2214 | info->index.sym = i; | |
2215 | info->index.str = info->sechdrs[i].sh_link; | |
2216 | info->strtab = (char *)info->hdr | |
2217 | + info->sechdrs[info->index.str].sh_offset; | |
2218 | break; | |
2219 | } | |
2220 | } | |
2221 | ||
2222 | info->index.mod = find_sec(info, ".gnu.linkonce.this_module"); | |
2223 | if (!info->index.mod) { | |
2224 | printk(KERN_WARNING "No module found in object\n"); | |
2225 | return ERR_PTR(-ENOEXEC); | |
2226 | } | |
2227 | /* This is temporary: point mod into copy of data. */ | |
2228 | mod = (void *)info->sechdrs[info->index.mod].sh_addr; | |
2229 | ||
2230 | if (info->index.sym == 0) { | |
2231 | printk(KERN_WARNING "%s: module has no symbols (stripped?)\n", | |
2232 | mod->name); | |
2233 | return ERR_PTR(-ENOEXEC); | |
2234 | } | |
2235 | ||
2236 | info->index.pcpu = find_pcpusec(info); | |
2237 | ||
2238 | /* Check module struct version now, before we try to use module. */ | |
2239 | if (!check_modstruct_version(info->sechdrs, info->index.vers, mod)) | |
2240 | return ERR_PTR(-ENOEXEC); | |
2241 | ||
2242 | return mod; | |
2243 | } | |
2244 | ||
2245 | static int check_modinfo(struct module *mod, struct load_info *info) | |
2246 | { | |
2247 | const char *modmagic = get_modinfo(info, "vermagic"); | |
2248 | int err; | |
2249 | ||
2250 | /* This is allowed: modprobe --force will invalidate it. */ | |
2251 | if (!modmagic) { | |
2252 | err = try_to_force_load(mod, "bad vermagic"); | |
2253 | if (err) | |
2254 | return err; | |
2255 | } else if (!same_magic(modmagic, vermagic, info->index.vers)) { | |
2256 | printk(KERN_ERR "%s: version magic '%s' should be '%s'\n", | |
2257 | mod->name, modmagic, vermagic); | |
2258 | return -ENOEXEC; | |
2259 | } | |
2260 | ||
2261 | if (get_modinfo(info, "staging")) { | |
2262 | add_taint_module(mod, TAINT_CRAP); | |
2263 | printk(KERN_WARNING "%s: module is from the staging directory," | |
2264 | " the quality is unknown, you have been warned.\n", | |
2265 | mod->name); | |
2266 | } | |
2267 | ||
2268 | /* Set up license info based on the info section */ | |
2269 | set_license(mod, get_modinfo(info, "license")); | |
2270 | ||
2271 | return 0; | |
2272 | } | |
2273 | ||
2274 | static void find_module_sections(struct module *mod, struct load_info *info) | |
2275 | { | |
2276 | mod->kp = section_objs(info, "__param", | |
2277 | sizeof(*mod->kp), &mod->num_kp); | |
2278 | mod->syms = section_objs(info, "__ksymtab", | |
2279 | sizeof(*mod->syms), &mod->num_syms); | |
2280 | mod->crcs = section_addr(info, "__kcrctab"); | |
2281 | mod->gpl_syms = section_objs(info, "__ksymtab_gpl", | |
2282 | sizeof(*mod->gpl_syms), | |
2283 | &mod->num_gpl_syms); | |
2284 | mod->gpl_crcs = section_addr(info, "__kcrctab_gpl"); | |
2285 | mod->gpl_future_syms = section_objs(info, | |
2286 | "__ksymtab_gpl_future", | |
2287 | sizeof(*mod->gpl_future_syms), | |
2288 | &mod->num_gpl_future_syms); | |
2289 | mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future"); | |
2290 | ||
2291 | #ifdef CONFIG_UNUSED_SYMBOLS | |
2292 | mod->unused_syms = section_objs(info, "__ksymtab_unused", | |
2293 | sizeof(*mod->unused_syms), | |
2294 | &mod->num_unused_syms); | |
2295 | mod->unused_crcs = section_addr(info, "__kcrctab_unused"); | |
2296 | mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl", | |
2297 | sizeof(*mod->unused_gpl_syms), | |
2298 | &mod->num_unused_gpl_syms); | |
2299 | mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl"); | |
2300 | #endif | |
2301 | #ifdef CONFIG_CONSTRUCTORS | |
2302 | mod->ctors = section_objs(info, ".ctors", | |
2303 | sizeof(*mod->ctors), &mod->num_ctors); | |
2304 | #endif | |
2305 | ||
2306 | #ifdef CONFIG_TRACEPOINTS | |
2307 | mod->tracepoints = section_objs(info, "__tracepoints", | |
2308 | sizeof(*mod->tracepoints), | |
2309 | &mod->num_tracepoints); | |
2310 | #endif | |
2311 | #ifdef CONFIG_EVENT_TRACING | |
2312 | mod->trace_events = section_objs(info, "_ftrace_events", | |
2313 | sizeof(*mod->trace_events), | |
2314 | &mod->num_trace_events); | |
2315 | /* | |
2316 | * This section contains pointers to allocated objects in the trace | |
2317 | * code and not scanning it leads to false positives. | |
2318 | */ | |
2319 | kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) * | |
2320 | mod->num_trace_events, GFP_KERNEL); | |
2321 | #endif | |
2322 | #ifdef CONFIG_FTRACE_MCOUNT_RECORD | |
2323 | /* sechdrs[0].sh_size is always zero */ | |
2324 | mod->ftrace_callsites = section_objs(info, "__mcount_loc", | |
2325 | sizeof(*mod->ftrace_callsites), | |
2326 | &mod->num_ftrace_callsites); | |
2327 | #endif | |
2328 | ||
2329 | mod->extable = section_objs(info, "__ex_table", | |
2330 | sizeof(*mod->extable), &mod->num_exentries); | |
2331 | ||
2332 | if (section_addr(info, "__obsparm")) | |
2333 | printk(KERN_WARNING "%s: Ignoring obsolete parameters\n", | |
2334 | mod->name); | |
2335 | ||
2336 | info->debug = section_objs(info, "__verbose", | |
2337 | sizeof(*info->debug), &info->num_debug); | |
2338 | } | |
2339 | ||
2340 | static int move_module(struct module *mod, struct load_info *info) | |
2341 | { | |
2342 | int i; | |
2343 | void *ptr; | |
2344 | ||
2345 | /* Do the allocs. */ | |
2346 | ptr = module_alloc_update_bounds(mod->core_size); | |
2347 | /* | |
2348 | * The pointer to this block is stored in the module structure | |
2349 | * which is inside the block. Just mark it as not being a | |
2350 | * leak. | |
2351 | */ | |
2352 | kmemleak_not_leak(ptr); | |
2353 | if (!ptr) | |
2354 | return -ENOMEM; | |
2355 | ||
2356 | memset(ptr, 0, mod->core_size); | |
2357 | mod->module_core = ptr; | |
2358 | ||
2359 | ptr = module_alloc_update_bounds(mod->init_size); | |
2360 | /* | |
2361 | * The pointer to this block is stored in the module structure | |
2362 | * which is inside the block. This block doesn't need to be | |
2363 | * scanned as it contains data and code that will be freed | |
2364 | * after the module is initialized. | |
2365 | */ | |
2366 | kmemleak_ignore(ptr); | |
2367 | if (!ptr && mod->init_size) { | |
2368 | module_free(mod, mod->module_core); | |
2369 | return -ENOMEM; | |
2370 | } | |
2371 | memset(ptr, 0, mod->init_size); | |
2372 | mod->module_init = ptr; | |
2373 | ||
2374 | /* Transfer each section which specifies SHF_ALLOC */ | |
2375 | DEBUGP("final section addresses:\n"); | |
2376 | for (i = 0; i < info->hdr->e_shnum; i++) { | |
2377 | void *dest; | |
2378 | Elf_Shdr *shdr = &info->sechdrs[i]; | |
2379 | ||
2380 | if (!(shdr->sh_flags & SHF_ALLOC)) | |
2381 | continue; | |
2382 | ||
2383 | if (shdr->sh_entsize & INIT_OFFSET_MASK) | |
2384 | dest = mod->module_init | |
2385 | + (shdr->sh_entsize & ~INIT_OFFSET_MASK); | |
2386 | else | |
2387 | dest = mod->module_core + shdr->sh_entsize; | |
2388 | ||
2389 | if (shdr->sh_type != SHT_NOBITS) | |
2390 | memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size); | |
2391 | /* Update sh_addr to point to copy in image. */ | |
2392 | shdr->sh_addr = (unsigned long)dest; | |
2393 | DEBUGP("\t0x%lx %s\n", | |
2394 | shdr->sh_addr, info->secstrings + shdr->sh_name); | |
2395 | } | |
2396 | ||
2397 | return 0; | |
2398 | } | |
2399 | ||
2400 | static int check_module_license_and_versions(struct module *mod) | |
2401 | { | |
2402 | /* | |
2403 | * ndiswrapper is under GPL by itself, but loads proprietary modules. | |
2404 | * Don't use add_taint_module(), as it would prevent ndiswrapper from | |
2405 | * using GPL-only symbols it needs. | |
2406 | */ | |
2407 | if (strcmp(mod->name, "ndiswrapper") == 0) | |
2408 | add_taint(TAINT_PROPRIETARY_MODULE); | |
2409 | ||
2410 | /* driverloader was caught wrongly pretending to be under GPL */ | |
2411 | if (strcmp(mod->name, "driverloader") == 0) | |
2412 | add_taint_module(mod, TAINT_PROPRIETARY_MODULE); | |
2413 | ||
2414 | #ifdef CONFIG_MODVERSIONS | |
2415 | if ((mod->num_syms && !mod->crcs) | |
2416 | || (mod->num_gpl_syms && !mod->gpl_crcs) | |
2417 | || (mod->num_gpl_future_syms && !mod->gpl_future_crcs) | |
2418 | #ifdef CONFIG_UNUSED_SYMBOLS | |
2419 | || (mod->num_unused_syms && !mod->unused_crcs) | |
2420 | || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs) | |
2421 | #endif | |
2422 | ) { | |
2423 | return try_to_force_load(mod, | |
2424 | "no versions for exported symbols"); | |
2425 | } | |
2426 | #endif | |
2427 | return 0; | |
2428 | } | |
2429 | ||
2430 | static void flush_module_icache(const struct module *mod) | |
2431 | { | |
2432 | mm_segment_t old_fs; | |
2433 | ||
2434 | /* flush the icache in correct context */ | |
2435 | old_fs = get_fs(); | |
2436 | set_fs(KERNEL_DS); | |
2437 | ||
2438 | /* | |
2439 | * Flush the instruction cache, since we've played with text. | |
2440 | * Do it before processing of module parameters, so the module | |
2441 | * can provide parameter accessor functions of its own. | |
2442 | */ | |
2443 | if (mod->module_init) | |
2444 | flush_icache_range((unsigned long)mod->module_init, | |
2445 | (unsigned long)mod->module_init | |
2446 | + mod->init_size); | |
2447 | flush_icache_range((unsigned long)mod->module_core, | |
2448 | (unsigned long)mod->module_core + mod->core_size); | |
2449 | ||
2450 | set_fs(old_fs); | |
2451 | } | |
2452 | ||
2453 | static struct module *layout_and_allocate(struct load_info *info) | |
2454 | { | |
2455 | /* Module within temporary copy. */ | |
2456 | struct module *mod; | |
2457 | Elf_Shdr *pcpusec; | |
2458 | int err; | |
2459 | ||
2460 | mod = setup_load_info(info); | |
2461 | if (IS_ERR(mod)) | |
2462 | return mod; | |
2463 | ||
2464 | err = check_modinfo(mod, info); | |
2465 | if (err) | |
2466 | return ERR_PTR(err); | |
2467 | ||
2468 | /* Allow arches to frob section contents and sizes. */ | |
2469 | err = module_frob_arch_sections(info->hdr, info->sechdrs, | |
2470 | info->secstrings, mod); | |
2471 | if (err < 0) | |
2472 | goto out; | |
2473 | ||
2474 | pcpusec = &info->sechdrs[info->index.pcpu]; | |
2475 | if (pcpusec->sh_size) { | |
2476 | /* We have a special allocation for this section. */ | |
2477 | err = percpu_modalloc(mod, | |
2478 | pcpusec->sh_size, pcpusec->sh_addralign); | |
2479 | if (err) | |
2480 | goto out; | |
2481 | pcpusec->sh_flags &= ~(unsigned long)SHF_ALLOC; | |
2482 | } | |
2483 | ||
2484 | /* Determine total sizes, and put offsets in sh_entsize. For now | |
2485 | this is done generically; there doesn't appear to be any | |
2486 | special cases for the architectures. */ | |
2487 | layout_sections(mod, info); | |
2488 | ||
2489 | info->strmap = kzalloc(BITS_TO_LONGS(info->sechdrs[info->index.str].sh_size) | |
2490 | * sizeof(long), GFP_KERNEL); | |
2491 | if (!info->strmap) { | |
2492 | err = -ENOMEM; | |
2493 | goto free_percpu; | |
2494 | } | |
2495 | layout_symtab(mod, info); | |
2496 | ||
2497 | /* Allocate and move to the final place */ | |
2498 | err = move_module(mod, info); | |
2499 | if (err) | |
2500 | goto free_strmap; | |
2501 | ||
2502 | /* Module has been copied to its final place now: return it. */ | |
2503 | mod = (void *)info->sechdrs[info->index.mod].sh_addr; | |
2504 | kmemleak_load_module(mod, info); | |
2505 | return mod; | |
2506 | ||
2507 | free_strmap: | |
2508 | kfree(info->strmap); | |
2509 | free_percpu: | |
2510 | percpu_modfree(mod); | |
2511 | out: | |
2512 | return ERR_PTR(err); | |
2513 | } | |
2514 | ||
2515 | /* mod is no longer valid after this! */ | |
2516 | static void module_deallocate(struct module *mod, struct load_info *info) | |
2517 | { | |
2518 | kfree(info->strmap); | |
2519 | percpu_modfree(mod); | |
2520 | module_free(mod, mod->module_init); | |
2521 | module_free(mod, mod->module_core); | |
2522 | } | |
2523 | ||
2524 | static int post_relocation(struct module *mod, const struct load_info *info) | |
2525 | { | |
2526 | /* Sort exception table now relocations are done. */ | |
2527 | sort_extable(mod->extable, mod->extable + mod->num_exentries); | |
2528 | ||
2529 | /* Copy relocated percpu area over. */ | |
2530 | percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr, | |
2531 | info->sechdrs[info->index.pcpu].sh_size); | |
2532 | ||
2533 | /* Setup kallsyms-specific fields. */ | |
2534 | add_kallsyms(mod, info); | |
2535 | ||
2536 | /* Arch-specific module finalizing. */ | |
2537 | return module_finalize(info->hdr, info->sechdrs, mod); | |
2538 | } | |
2539 | ||
2540 | /* Allocate and load the module: note that size of section 0 is always | |
2541 | zero, and we rely on this for optional sections. */ | |
2542 | static struct module *load_module(void __user *umod, | |
2543 | unsigned long len, | |
2544 | const char __user *uargs) | |
2545 | { | |
2546 | struct load_info info = { NULL, }; | |
2547 | struct module *mod; | |
2548 | long err; | |
2549 | ||
2550 | DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n", | |
2551 | umod, len, uargs); | |
2552 | ||
2553 | /* Copy in the blobs from userspace, check they are vaguely sane. */ | |
2554 | err = copy_and_check(&info, umod, len, uargs); | |
2555 | if (err) | |
2556 | return ERR_PTR(err); | |
2557 | ||
2558 | /* Figure out module layout, and allocate all the memory. */ | |
2559 | mod = layout_and_allocate(&info); | |
2560 | if (IS_ERR(mod)) { | |
2561 | err = PTR_ERR(mod); | |
2562 | goto free_copy; | |
2563 | } | |
2564 | ||
2565 | /* Now module is in final location, initialize linked lists, etc. */ | |
2566 | err = module_unload_init(mod); | |
2567 | if (err) | |
2568 | goto free_module; | |
2569 | ||
2570 | /* Now we've got everything in the final locations, we can | |
2571 | * find optional sections. */ | |
2572 | find_module_sections(mod, &info); | |
2573 | ||
2574 | err = check_module_license_and_versions(mod); | |
2575 | if (err) | |
2576 | goto free_unload; | |
2577 | ||
2578 | /* Set up MODINFO_ATTR fields */ | |
2579 | setup_modinfo(mod, &info); | |
2580 | ||
2581 | /* Fix up syms, so that st_value is a pointer to location. */ | |
2582 | err = simplify_symbols(mod, &info); | |
2583 | if (err < 0) | |
2584 | goto free_modinfo; | |
2585 | ||
2586 | err = apply_relocations(mod, &info); | |
2587 | if (err < 0) | |
2588 | goto free_modinfo; | |
2589 | ||
2590 | err = post_relocation(mod, &info); | |
2591 | if (err < 0) | |
2592 | goto free_modinfo; | |
2593 | ||
2594 | flush_module_icache(mod); | |
2595 | ||
2596 | /* Now copy in args */ | |
2597 | mod->args = strndup_user(uargs, ~0UL >> 1); | |
2598 | if (IS_ERR(mod->args)) { | |
2599 | err = PTR_ERR(mod->args); | |
2600 | goto free_arch_cleanup; | |
2601 | } | |
2602 | ||
2603 | /* Mark state as coming so strong_try_module_get() ignores us. */ | |
2604 | mod->state = MODULE_STATE_COMING; | |
2605 | ||
2606 | /* Now sew it into the lists so we can get lockdep and oops | |
2607 | * info during argument parsing. Noone should access us, since | |
2608 | * strong_try_module_get() will fail. | |
2609 | * lockdep/oops can run asynchronous, so use the RCU list insertion | |
2610 | * function to insert in a way safe to concurrent readers. | |
2611 | * The mutex protects against concurrent writers. | |
2612 | */ | |
2613 | mutex_lock(&module_mutex); | |
2614 | if (find_module(mod->name)) { | |
2615 | err = -EEXIST; | |
2616 | goto unlock; | |
2617 | } | |
2618 | ||
2619 | /* This has to be done once we're sure module name is unique. */ | |
2620 | if (!mod->taints) | |
2621 | dynamic_debug_setup(info.debug, info.num_debug); | |
2622 | ||
2623 | /* Find duplicate symbols */ | |
2624 | err = verify_export_symbols(mod); | |
2625 | if (err < 0) | |
2626 | goto ddebug; | |
2627 | ||
2628 | list_add_rcu(&mod->list, &modules); | |
2629 | mutex_unlock(&module_mutex); | |
2630 | ||
2631 | /* Module is ready to execute: parsing args may do that. */ | |
2632 | err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL); | |
2633 | if (err < 0) | |
2634 | goto unlink; | |
2635 | ||
2636 | /* Link in to syfs. */ | |
2637 | err = mod_sysfs_setup(mod, &info, mod->kp, mod->num_kp); | |
2638 | if (err < 0) | |
2639 | goto unlink; | |
2640 | ||
2641 | /* Get rid of temporary copy and strmap. */ | |
2642 | kfree(info.strmap); | |
2643 | free_copy(&info); | |
2644 | ||
2645 | /* Done! */ | |
2646 | trace_module_load(mod); | |
2647 | return mod; | |
2648 | ||
2649 | unlink: | |
2650 | mutex_lock(&module_mutex); | |
2651 | /* Unlink carefully: kallsyms could be walking list. */ | |
2652 | list_del_rcu(&mod->list); | |
2653 | ddebug: | |
2654 | if (!mod->taints) | |
2655 | dynamic_debug_remove(info.debug); | |
2656 | unlock: | |
2657 | mutex_unlock(&module_mutex); | |
2658 | synchronize_sched(); | |
2659 | kfree(mod->args); | |
2660 | free_arch_cleanup: | |
2661 | module_arch_cleanup(mod); | |
2662 | free_modinfo: | |
2663 | free_modinfo(mod); | |
2664 | free_unload: | |
2665 | module_unload_free(mod); | |
2666 | free_module: | |
2667 | module_deallocate(mod, &info); | |
2668 | free_copy: | |
2669 | free_copy(&info); | |
2670 | return ERR_PTR(err); | |
2671 | } | |
2672 | ||
2673 | /* Call module constructors. */ | |
2674 | static void do_mod_ctors(struct module *mod) | |
2675 | { | |
2676 | #ifdef CONFIG_CONSTRUCTORS | |
2677 | unsigned long i; | |
2678 | ||
2679 | for (i = 0; i < mod->num_ctors; i++) | |
2680 | mod->ctors[i](); | |
2681 | #endif | |
2682 | } | |
2683 | ||
2684 | /* This is where the real work happens */ | |
2685 | SYSCALL_DEFINE3(init_module, void __user *, umod, | |
2686 | unsigned long, len, const char __user *, uargs) | |
2687 | { | |
2688 | struct module *mod; | |
2689 | int ret = 0; | |
2690 | ||
2691 | /* Must have permission */ | |
2692 | if (!capable(CAP_SYS_MODULE) || modules_disabled) | |
2693 | return -EPERM; | |
2694 | ||
2695 | /* Do all the hard work */ | |
2696 | mod = load_module(umod, len, uargs); | |
2697 | if (IS_ERR(mod)) | |
2698 | return PTR_ERR(mod); | |
2699 | ||
2700 | blocking_notifier_call_chain(&module_notify_list, | |
2701 | MODULE_STATE_COMING, mod); | |
2702 | ||
2703 | do_mod_ctors(mod); | |
2704 | /* Start the module */ | |
2705 | if (mod->init != NULL) | |
2706 | ret = do_one_initcall(mod->init); | |
2707 | if (ret < 0) { | |
2708 | /* Init routine failed: abort. Try to protect us from | |
2709 | buggy refcounters. */ | |
2710 | mod->state = MODULE_STATE_GOING; | |
2711 | synchronize_sched(); | |
2712 | module_put(mod); | |
2713 | blocking_notifier_call_chain(&module_notify_list, | |
2714 | MODULE_STATE_GOING, mod); | |
2715 | free_module(mod); | |
2716 | wake_up(&module_wq); | |
2717 | return ret; | |
2718 | } | |
2719 | if (ret > 0) { | |
2720 | printk(KERN_WARNING | |
2721 | "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n" | |
2722 | "%s: loading module anyway...\n", | |
2723 | __func__, mod->name, ret, | |
2724 | __func__); | |
2725 | dump_stack(); | |
2726 | } | |
2727 | ||
2728 | /* Now it's a first class citizen! Wake up anyone waiting for it. */ | |
2729 | mod->state = MODULE_STATE_LIVE; | |
2730 | wake_up(&module_wq); | |
2731 | blocking_notifier_call_chain(&module_notify_list, | |
2732 | MODULE_STATE_LIVE, mod); | |
2733 | ||
2734 | /* We need to finish all async code before the module init sequence is done */ | |
2735 | async_synchronize_full(); | |
2736 | ||
2737 | mutex_lock(&module_mutex); | |
2738 | /* Drop initial reference. */ | |
2739 | module_put(mod); | |
2740 | trim_init_extable(mod); | |
2741 | #ifdef CONFIG_KALLSYMS | |
2742 | mod->num_symtab = mod->core_num_syms; | |
2743 | mod->symtab = mod->core_symtab; | |
2744 | mod->strtab = mod->core_strtab; | |
2745 | #endif | |
2746 | module_free(mod, mod->module_init); | |
2747 | mod->module_init = NULL; | |
2748 | mod->init_size = 0; | |
2749 | mod->init_text_size = 0; | |
2750 | mutex_unlock(&module_mutex); | |
2751 | ||
2752 | return 0; | |
2753 | } | |
2754 | ||
2755 | static inline int within(unsigned long addr, void *start, unsigned long size) | |
2756 | { | |
2757 | return ((void *)addr >= start && (void *)addr < start + size); | |
2758 | } | |
2759 | ||
2760 | #ifdef CONFIG_KALLSYMS | |
2761 | /* | |
2762 | * This ignores the intensely annoying "mapping symbols" found | |
2763 | * in ARM ELF files: $a, $t and $d. | |
2764 | */ | |
2765 | static inline int is_arm_mapping_symbol(const char *str) | |
2766 | { | |
2767 | return str[0] == '$' && strchr("atd", str[1]) | |
2768 | && (str[2] == '\0' || str[2] == '.'); | |
2769 | } | |
2770 | ||
2771 | static const char *get_ksymbol(struct module *mod, | |
2772 | unsigned long addr, | |
2773 | unsigned long *size, | |
2774 | unsigned long *offset) | |
2775 | { | |
2776 | unsigned int i, best = 0; | |
2777 | unsigned long nextval; | |
2778 | ||
2779 | /* At worse, next value is at end of module */ | |
2780 | if (within_module_init(addr, mod)) | |
2781 | nextval = (unsigned long)mod->module_init+mod->init_text_size; | |
2782 | else | |
2783 | nextval = (unsigned long)mod->module_core+mod->core_text_size; | |
2784 | ||
2785 | /* Scan for closest preceeding symbol, and next symbol. (ELF | |
2786 | starts real symbols at 1). */ | |
2787 | for (i = 1; i < mod->num_symtab; i++) { | |
2788 | if (mod->symtab[i].st_shndx == SHN_UNDEF) | |
2789 | continue; | |
2790 | ||
2791 | /* We ignore unnamed symbols: they're uninformative | |
2792 | * and inserted at a whim. */ | |
2793 | if (mod->symtab[i].st_value <= addr | |
2794 | && mod->symtab[i].st_value > mod->symtab[best].st_value | |
2795 | && *(mod->strtab + mod->symtab[i].st_name) != '\0' | |
2796 | && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name)) | |
2797 | best = i; | |
2798 | if (mod->symtab[i].st_value > addr | |
2799 | && mod->symtab[i].st_value < nextval | |
2800 | && *(mod->strtab + mod->symtab[i].st_name) != '\0' | |
2801 | && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name)) | |
2802 | nextval = mod->symtab[i].st_value; | |
2803 | } | |
2804 | ||
2805 | if (!best) | |
2806 | return NULL; | |
2807 | ||
2808 | if (size) | |
2809 | *size = nextval - mod->symtab[best].st_value; | |
2810 | if (offset) | |
2811 | *offset = addr - mod->symtab[best].st_value; | |
2812 | return mod->strtab + mod->symtab[best].st_name; | |
2813 | } | |
2814 | ||
2815 | /* For kallsyms to ask for address resolution. NULL means not found. Careful | |
2816 | * not to lock to avoid deadlock on oopses, simply disable preemption. */ | |
2817 | const char *module_address_lookup(unsigned long addr, | |
2818 | unsigned long *size, | |
2819 | unsigned long *offset, | |
2820 | char **modname, | |
2821 | char *namebuf) | |
2822 | { | |
2823 | struct module *mod; | |
2824 | const char *ret = NULL; | |
2825 | ||
2826 | preempt_disable(); | |
2827 | list_for_each_entry_rcu(mod, &modules, list) { | |
2828 | if (within_module_init(addr, mod) || | |
2829 | within_module_core(addr, mod)) { | |
2830 | if (modname) | |
2831 | *modname = mod->name; | |
2832 | ret = get_ksymbol(mod, addr, size, offset); | |
2833 | break; | |
2834 | } | |
2835 | } | |
2836 | /* Make a copy in here where it's safe */ | |
2837 | if (ret) { | |
2838 | strncpy(namebuf, ret, KSYM_NAME_LEN - 1); | |
2839 | ret = namebuf; | |
2840 | } | |
2841 | preempt_enable(); | |
2842 | return ret; | |
2843 | } | |
2844 | ||
2845 | int lookup_module_symbol_name(unsigned long addr, char *symname) | |
2846 | { | |
2847 | struct module *mod; | |
2848 | ||
2849 | preempt_disable(); | |
2850 | list_for_each_entry_rcu(mod, &modules, list) { | |
2851 | if (within_module_init(addr, mod) || | |
2852 | within_module_core(addr, mod)) { | |
2853 | const char *sym; | |
2854 | ||
2855 | sym = get_ksymbol(mod, addr, NULL, NULL); | |
2856 | if (!sym) | |
2857 | goto out; | |
2858 | strlcpy(symname, sym, KSYM_NAME_LEN); | |
2859 | preempt_enable(); | |
2860 | return 0; | |
2861 | } | |
2862 | } | |
2863 | out: | |
2864 | preempt_enable(); | |
2865 | return -ERANGE; | |
2866 | } | |
2867 | ||
2868 | int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, | |
2869 | unsigned long *offset, char *modname, char *name) | |
2870 | { | |
2871 | struct module *mod; | |
2872 | ||
2873 | preempt_disable(); | |
2874 | list_for_each_entry_rcu(mod, &modules, list) { | |
2875 | if (within_module_init(addr, mod) || | |
2876 | within_module_core(addr, mod)) { | |
2877 | const char *sym; | |
2878 | ||
2879 | sym = get_ksymbol(mod, addr, size, offset); | |
2880 | if (!sym) | |
2881 | goto out; | |
2882 | if (modname) | |
2883 | strlcpy(modname, mod->name, MODULE_NAME_LEN); | |
2884 | if (name) | |
2885 | strlcpy(name, sym, KSYM_NAME_LEN); | |
2886 | preempt_enable(); | |
2887 | return 0; | |
2888 | } | |
2889 | } | |
2890 | out: | |
2891 | preempt_enable(); | |
2892 | return -ERANGE; | |
2893 | } | |
2894 | ||
2895 | int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, | |
2896 | char *name, char *module_name, int *exported) | |
2897 | { | |
2898 | struct module *mod; | |
2899 | ||
2900 | preempt_disable(); | |
2901 | list_for_each_entry_rcu(mod, &modules, list) { | |
2902 | if (symnum < mod->num_symtab) { | |
2903 | *value = mod->symtab[symnum].st_value; | |
2904 | *type = mod->symtab[symnum].st_info; | |
2905 | strlcpy(name, mod->strtab + mod->symtab[symnum].st_name, | |
2906 | KSYM_NAME_LEN); | |
2907 | strlcpy(module_name, mod->name, MODULE_NAME_LEN); | |
2908 | *exported = is_exported(name, *value, mod); | |
2909 | preempt_enable(); | |
2910 | return 0; | |
2911 | } | |
2912 | symnum -= mod->num_symtab; | |
2913 | } | |
2914 | preempt_enable(); | |
2915 | return -ERANGE; | |
2916 | } | |
2917 | ||
2918 | static unsigned long mod_find_symname(struct module *mod, const char *name) | |
2919 | { | |
2920 | unsigned int i; | |
2921 | ||
2922 | for (i = 0; i < mod->num_symtab; i++) | |
2923 | if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 && | |
2924 | mod->symtab[i].st_info != 'U') | |
2925 | return mod->symtab[i].st_value; | |
2926 | return 0; | |
2927 | } | |
2928 | ||
2929 | /* Look for this name: can be of form module:name. */ | |
2930 | unsigned long module_kallsyms_lookup_name(const char *name) | |
2931 | { | |
2932 | struct module *mod; | |
2933 | char *colon; | |
2934 | unsigned long ret = 0; | |
2935 | ||
2936 | /* Don't lock: we're in enough trouble already. */ | |
2937 | preempt_disable(); | |
2938 | if ((colon = strchr(name, ':')) != NULL) { | |
2939 | *colon = '\0'; | |
2940 | if ((mod = find_module(name)) != NULL) | |
2941 | ret = mod_find_symname(mod, colon+1); | |
2942 | *colon = ':'; | |
2943 | } else { | |
2944 | list_for_each_entry_rcu(mod, &modules, list) | |
2945 | if ((ret = mod_find_symname(mod, name)) != 0) | |
2946 | break; | |
2947 | } | |
2948 | preempt_enable(); | |
2949 | return ret; | |
2950 | } | |
2951 | ||
2952 | int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, | |
2953 | struct module *, unsigned long), | |
2954 | void *data) | |
2955 | { | |
2956 | struct module *mod; | |
2957 | unsigned int i; | |
2958 | int ret; | |
2959 | ||
2960 | list_for_each_entry(mod, &modules, list) { | |
2961 | for (i = 0; i < mod->num_symtab; i++) { | |
2962 | ret = fn(data, mod->strtab + mod->symtab[i].st_name, | |
2963 | mod, mod->symtab[i].st_value); | |
2964 | if (ret != 0) | |
2965 | return ret; | |
2966 | } | |
2967 | } | |
2968 | return 0; | |
2969 | } | |
2970 | #endif /* CONFIG_KALLSYMS */ | |
2971 | ||
2972 | static char *module_flags(struct module *mod, char *buf) | |
2973 | { | |
2974 | int bx = 0; | |
2975 | ||
2976 | if (mod->taints || | |
2977 | mod->state == MODULE_STATE_GOING || | |
2978 | mod->state == MODULE_STATE_COMING) { | |
2979 | buf[bx++] = '('; | |
2980 | if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE)) | |
2981 | buf[bx++] = 'P'; | |
2982 | if (mod->taints & (1 << TAINT_FORCED_MODULE)) | |
2983 | buf[bx++] = 'F'; | |
2984 | if (mod->taints & (1 << TAINT_CRAP)) | |
2985 | buf[bx++] = 'C'; | |
2986 | /* | |
2987 | * TAINT_FORCED_RMMOD: could be added. | |
2988 | * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't | |
2989 | * apply to modules. | |
2990 | */ | |
2991 | ||
2992 | /* Show a - for module-is-being-unloaded */ | |
2993 | if (mod->state == MODULE_STATE_GOING) | |
2994 | buf[bx++] = '-'; | |
2995 | /* Show a + for module-is-being-loaded */ | |
2996 | if (mod->state == MODULE_STATE_COMING) | |
2997 | buf[bx++] = '+'; | |
2998 | buf[bx++] = ')'; | |
2999 | } | |
3000 | buf[bx] = '\0'; | |
3001 | ||
3002 | return buf; | |
3003 | } | |
3004 | ||
3005 | #ifdef CONFIG_PROC_FS | |
3006 | /* Called by the /proc file system to return a list of modules. */ | |
3007 | static void *m_start(struct seq_file *m, loff_t *pos) | |
3008 | { | |
3009 | mutex_lock(&module_mutex); | |
3010 | return seq_list_start(&modules, *pos); | |
3011 | } | |
3012 | ||
3013 | static void *m_next(struct seq_file *m, void *p, loff_t *pos) | |
3014 | { | |
3015 | return seq_list_next(p, &modules, pos); | |
3016 | } | |
3017 | ||
3018 | static void m_stop(struct seq_file *m, void *p) | |
3019 | { | |
3020 | mutex_unlock(&module_mutex); | |
3021 | } | |
3022 | ||
3023 | static int m_show(struct seq_file *m, void *p) | |
3024 | { | |
3025 | struct module *mod = list_entry(p, struct module, list); | |
3026 | char buf[8]; | |
3027 | ||
3028 | seq_printf(m, "%s %u", | |
3029 | mod->name, mod->init_size + mod->core_size); | |
3030 | print_unload_info(m, mod); | |
3031 | ||
3032 | /* Informative for users. */ | |
3033 | seq_printf(m, " %s", | |
3034 | mod->state == MODULE_STATE_GOING ? "Unloading": | |
3035 | mod->state == MODULE_STATE_COMING ? "Loading": | |
3036 | "Live"); | |
3037 | /* Used by oprofile and other similar tools. */ | |
3038 | seq_printf(m, " 0x%p", mod->module_core); | |
3039 | ||
3040 | /* Taints info */ | |
3041 | if (mod->taints) | |
3042 | seq_printf(m, " %s", module_flags(mod, buf)); | |
3043 | ||
3044 | seq_printf(m, "\n"); | |
3045 | return 0; | |
3046 | } | |
3047 | ||
3048 | /* Format: modulename size refcount deps address | |
3049 | ||
3050 | Where refcount is a number or -, and deps is a comma-separated list | |
3051 | of depends or -. | |
3052 | */ | |
3053 | static const struct seq_operations modules_op = { | |
3054 | .start = m_start, | |
3055 | .next = m_next, | |
3056 | .stop = m_stop, | |
3057 | .show = m_show | |
3058 | }; | |
3059 | ||
3060 | static int modules_open(struct inode *inode, struct file *file) | |
3061 | { | |
3062 | return seq_open(file, &modules_op); | |
3063 | } | |
3064 | ||
3065 | static const struct file_operations proc_modules_operations = { | |
3066 | .open = modules_open, | |
3067 | .read = seq_read, | |
3068 | .llseek = seq_lseek, | |
3069 | .release = seq_release, | |
3070 | }; | |
3071 | ||
3072 | static int __init proc_modules_init(void) | |
3073 | { | |
3074 | proc_create("modules", 0, NULL, &proc_modules_operations); | |
3075 | return 0; | |
3076 | } | |
3077 | module_init(proc_modules_init); | |
3078 | #endif | |
3079 | ||
3080 | /* Given an address, look for it in the module exception tables. */ | |
3081 | const struct exception_table_entry *search_module_extables(unsigned long addr) | |
3082 | { | |
3083 | const struct exception_table_entry *e = NULL; | |
3084 | struct module *mod; | |
3085 | ||
3086 | preempt_disable(); | |
3087 | list_for_each_entry_rcu(mod, &modules, list) { | |
3088 | if (mod->num_exentries == 0) | |
3089 | continue; | |
3090 | ||
3091 | e = search_extable(mod->extable, | |
3092 | mod->extable + mod->num_exentries - 1, | |
3093 | addr); | |
3094 | if (e) | |
3095 | break; | |
3096 | } | |
3097 | preempt_enable(); | |
3098 | ||
3099 | /* Now, if we found one, we are running inside it now, hence | |
3100 | we cannot unload the module, hence no refcnt needed. */ | |
3101 | return e; | |
3102 | } | |
3103 | ||
3104 | /* | |
3105 | * is_module_address - is this address inside a module? | |
3106 | * @addr: the address to check. | |
3107 | * | |
3108 | * See is_module_text_address() if you simply want to see if the address | |
3109 | * is code (not data). | |
3110 | */ | |
3111 | bool is_module_address(unsigned long addr) | |
3112 | { | |
3113 | bool ret; | |
3114 | ||
3115 | preempt_disable(); | |
3116 | ret = __module_address(addr) != NULL; | |
3117 | preempt_enable(); | |
3118 | ||
3119 | return ret; | |
3120 | } | |
3121 | ||
3122 | /* | |
3123 | * __module_address - get the module which contains an address. | |
3124 | * @addr: the address. | |
3125 | * | |
3126 | * Must be called with preempt disabled or module mutex held so that | |
3127 | * module doesn't get freed during this. | |
3128 | */ | |
3129 | struct module *__module_address(unsigned long addr) | |
3130 | { | |
3131 | struct module *mod; | |
3132 | ||
3133 | if (addr < module_addr_min || addr > module_addr_max) | |
3134 | return NULL; | |
3135 | ||
3136 | list_for_each_entry_rcu(mod, &modules, list) | |
3137 | if (within_module_core(addr, mod) | |
3138 | || within_module_init(addr, mod)) | |
3139 | return mod; | |
3140 | return NULL; | |
3141 | } | |
3142 | EXPORT_SYMBOL_GPL(__module_address); | |
3143 | ||
3144 | /* | |
3145 | * is_module_text_address - is this address inside module code? | |
3146 | * @addr: the address to check. | |
3147 | * | |
3148 | * See is_module_address() if you simply want to see if the address is | |
3149 | * anywhere in a module. See kernel_text_address() for testing if an | |
3150 | * address corresponds to kernel or module code. | |
3151 | */ | |
3152 | bool is_module_text_address(unsigned long addr) | |
3153 | { | |
3154 | bool ret; | |
3155 | ||
3156 | preempt_disable(); | |
3157 | ret = __module_text_address(addr) != NULL; | |
3158 | preempt_enable(); | |
3159 | ||
3160 | return ret; | |
3161 | } | |
3162 | ||
3163 | /* | |
3164 | * __module_text_address - get the module whose code contains an address. | |
3165 | * @addr: the address. | |
3166 | * | |
3167 | * Must be called with preempt disabled or module mutex held so that | |
3168 | * module doesn't get freed during this. | |
3169 | */ | |
3170 | struct module *__module_text_address(unsigned long addr) | |
3171 | { | |
3172 | struct module *mod = __module_address(addr); | |
3173 | if (mod) { | |
3174 | /* Make sure it's within the text section. */ | |
3175 | if (!within(addr, mod->module_init, mod->init_text_size) | |
3176 | && !within(addr, mod->module_core, mod->core_text_size)) | |
3177 | mod = NULL; | |
3178 | } | |
3179 | return mod; | |
3180 | } | |
3181 | EXPORT_SYMBOL_GPL(__module_text_address); | |
3182 | ||
3183 | /* Don't grab lock, we're oopsing. */ | |
3184 | void print_modules(void) | |
3185 | { | |
3186 | struct module *mod; | |
3187 | char buf[8]; | |
3188 | ||
3189 | printk(KERN_DEFAULT "Modules linked in:"); | |
3190 | /* Most callers should already have preempt disabled, but make sure */ | |
3191 | preempt_disable(); | |
3192 | list_for_each_entry_rcu(mod, &modules, list) | |
3193 | printk(" %s%s", mod->name, module_flags(mod, buf)); | |
3194 | preempt_enable(); | |
3195 | if (last_unloaded_module[0]) | |
3196 | printk(" [last unloaded: %s]", last_unloaded_module); | |
3197 | printk("\n"); | |
3198 | } | |
3199 | ||
3200 | #ifdef CONFIG_MODVERSIONS | |
3201 | /* Generate the signature for all relevant module structures here. | |
3202 | * If these change, we don't want to try to parse the module. */ | |
3203 | void module_layout(struct module *mod, | |
3204 | struct modversion_info *ver, | |
3205 | struct kernel_param *kp, | |
3206 | struct kernel_symbol *ks, | |
3207 | struct tracepoint *tp) | |
3208 | { | |
3209 | } | |
3210 | EXPORT_SYMBOL(module_layout); | |
3211 | #endif | |
3212 | ||
3213 | #ifdef CONFIG_TRACEPOINTS | |
3214 | void module_update_tracepoints(void) | |
3215 | { | |
3216 | struct module *mod; | |
3217 | ||
3218 | mutex_lock(&module_mutex); | |
3219 | list_for_each_entry(mod, &modules, list) | |
3220 | if (!mod->taints) | |
3221 | tracepoint_update_probe_range(mod->tracepoints, | |
3222 | mod->tracepoints + mod->num_tracepoints); | |
3223 | mutex_unlock(&module_mutex); | |
3224 | } | |
3225 | ||
3226 | /* | |
3227 | * Returns 0 if current not found. | |
3228 | * Returns 1 if current found. | |
3229 | */ | |
3230 | int module_get_iter_tracepoints(struct tracepoint_iter *iter) | |
3231 | { | |
3232 | struct module *iter_mod; | |
3233 | int found = 0; | |
3234 | ||
3235 | mutex_lock(&module_mutex); | |
3236 | list_for_each_entry(iter_mod, &modules, list) { | |
3237 | if (!iter_mod->taints) { | |
3238 | /* | |
3239 | * Sorted module list | |
3240 | */ | |
3241 | if (iter_mod < iter->module) | |
3242 | continue; | |
3243 | else if (iter_mod > iter->module) | |
3244 | iter->tracepoint = NULL; | |
3245 | found = tracepoint_get_iter_range(&iter->tracepoint, | |
3246 | iter_mod->tracepoints, | |
3247 | iter_mod->tracepoints | |
3248 | + iter_mod->num_tracepoints); | |
3249 | if (found) { | |
3250 | iter->module = iter_mod; | |
3251 | break; | |
3252 | } | |
3253 | } | |
3254 | } | |
3255 | mutex_unlock(&module_mutex); | |
3256 | return found; | |
3257 | } | |
3258 | #endif |