Commit | Line | Data |
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1da177e4 LT |
1 | /* Rewritten by Rusty Russell, on the backs of many others... |
2 | Copyright (C) 2002 Richard Henderson | |
3 | Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM. | |
4 | ||
5 | This program is free software; you can redistribute it and/or modify | |
6 | it under the terms of the GNU General Public License as published by | |
7 | the Free Software Foundation; either version 2 of the License, or | |
8 | (at your option) any later version. | |
9 | ||
10 | This program is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | GNU General Public License for more details. | |
14 | ||
15 | You should have received a copy of the GNU General Public License | |
16 | along with this program; if not, write to the Free Software | |
17 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | */ | |
19 | #include <linux/config.h> | |
20 | #include <linux/module.h> | |
21 | #include <linux/moduleloader.h> | |
22 | #include <linux/init.h> | |
9f158333 | 23 | #include <linux/kernel.h> |
1da177e4 LT |
24 | #include <linux/slab.h> |
25 | #include <linux/vmalloc.h> | |
26 | #include <linux/elf.h> | |
27 | #include <linux/seq_file.h> | |
28 | #include <linux/syscalls.h> | |
29 | #include <linux/fcntl.h> | |
30 | #include <linux/rcupdate.h> | |
c59ede7b | 31 | #include <linux/capability.h> |
1da177e4 LT |
32 | #include <linux/cpu.h> |
33 | #include <linux/moduleparam.h> | |
34 | #include <linux/errno.h> | |
35 | #include <linux/err.h> | |
36 | #include <linux/vermagic.h> | |
37 | #include <linux/notifier.h> | |
38 | #include <linux/stop_machine.h> | |
39 | #include <linux/device.h> | |
c988d2b2 | 40 | #include <linux/string.h> |
8c65b4a6 | 41 | #include <linux/sched.h> |
97d1f15b | 42 | #include <linux/mutex.h> |
1da177e4 LT |
43 | #include <asm/uaccess.h> |
44 | #include <asm/semaphore.h> | |
45 | #include <asm/cacheflush.h> | |
46 | ||
47 | #if 0 | |
48 | #define DEBUGP printk | |
49 | #else | |
50 | #define DEBUGP(fmt , a...) | |
51 | #endif | |
52 | ||
53 | #ifndef ARCH_SHF_SMALL | |
54 | #define ARCH_SHF_SMALL 0 | |
55 | #endif | |
56 | ||
57 | /* If this is set, the section belongs in the init part of the module */ | |
58 | #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) | |
59 | ||
60 | /* Protects module list */ | |
61 | static DEFINE_SPINLOCK(modlist_lock); | |
62 | ||
63 | /* List of modules, protected by module_mutex AND modlist_lock */ | |
6389a385 | 64 | static DEFINE_MUTEX(module_mutex); |
1da177e4 LT |
65 | static LIST_HEAD(modules); |
66 | ||
97d1f15b | 67 | static DEFINE_MUTEX(notify_mutex); |
1da177e4 LT |
68 | static struct notifier_block * module_notify_list; |
69 | ||
70 | int register_module_notifier(struct notifier_block * nb) | |
71 | { | |
72 | int err; | |
97d1f15b | 73 | mutex_lock(¬ify_mutex); |
1da177e4 | 74 | err = notifier_chain_register(&module_notify_list, nb); |
97d1f15b | 75 | mutex_unlock(¬ify_mutex); |
1da177e4 LT |
76 | return err; |
77 | } | |
78 | EXPORT_SYMBOL(register_module_notifier); | |
79 | ||
80 | int unregister_module_notifier(struct notifier_block * nb) | |
81 | { | |
82 | int err; | |
97d1f15b | 83 | mutex_lock(¬ify_mutex); |
1da177e4 | 84 | err = notifier_chain_unregister(&module_notify_list, nb); |
97d1f15b | 85 | mutex_unlock(¬ify_mutex); |
1da177e4 LT |
86 | return err; |
87 | } | |
88 | EXPORT_SYMBOL(unregister_module_notifier); | |
89 | ||
90 | /* We require a truly strong try_module_get() */ | |
91 | static inline int strong_try_module_get(struct module *mod) | |
92 | { | |
93 | if (mod && mod->state == MODULE_STATE_COMING) | |
94 | return 0; | |
95 | return try_module_get(mod); | |
96 | } | |
97 | ||
98 | /* A thread that wants to hold a reference to a module only while it | |
99 | * is running can call ths to safely exit. | |
100 | * nfsd and lockd use this. | |
101 | */ | |
102 | void __module_put_and_exit(struct module *mod, long code) | |
103 | { | |
104 | module_put(mod); | |
105 | do_exit(code); | |
106 | } | |
107 | EXPORT_SYMBOL(__module_put_and_exit); | |
108 | ||
109 | /* Find a module section: 0 means not found. */ | |
110 | static unsigned int find_sec(Elf_Ehdr *hdr, | |
111 | Elf_Shdr *sechdrs, | |
112 | const char *secstrings, | |
113 | const char *name) | |
114 | { | |
115 | unsigned int i; | |
116 | ||
117 | for (i = 1; i < hdr->e_shnum; i++) | |
118 | /* Alloc bit cleared means "ignore it." */ | |
119 | if ((sechdrs[i].sh_flags & SHF_ALLOC) | |
120 | && strcmp(secstrings+sechdrs[i].sh_name, name) == 0) | |
121 | return i; | |
122 | return 0; | |
123 | } | |
124 | ||
125 | /* Provided by the linker */ | |
126 | extern const struct kernel_symbol __start___ksymtab[]; | |
127 | extern const struct kernel_symbol __stop___ksymtab[]; | |
128 | extern const struct kernel_symbol __start___ksymtab_gpl[]; | |
129 | extern const struct kernel_symbol __stop___ksymtab_gpl[]; | |
9f28bb7e GKH |
130 | extern const struct kernel_symbol __start___ksymtab_gpl_future[]; |
131 | extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; | |
1da177e4 LT |
132 | extern const unsigned long __start___kcrctab[]; |
133 | extern const unsigned long __start___kcrctab_gpl[]; | |
9f28bb7e | 134 | extern const unsigned long __start___kcrctab_gpl_future[]; |
1da177e4 LT |
135 | |
136 | #ifndef CONFIG_MODVERSIONS | |
137 | #define symversion(base, idx) NULL | |
138 | #else | |
139 | #define symversion(base, idx) ((base) ? ((base) + (idx)) : NULL) | |
140 | #endif | |
141 | ||
3fd6805f SR |
142 | /* lookup symbol in given range of kernel_symbols */ |
143 | static const struct kernel_symbol *lookup_symbol(const char *name, | |
144 | const struct kernel_symbol *start, | |
145 | const struct kernel_symbol *stop) | |
146 | { | |
147 | const struct kernel_symbol *ks = start; | |
148 | for (; ks < stop; ks++) | |
149 | if (strcmp(ks->name, name) == 0) | |
150 | return ks; | |
151 | return NULL; | |
152 | } | |
153 | ||
1da177e4 LT |
154 | /* Find a symbol, return value, crc and module which owns it */ |
155 | static unsigned long __find_symbol(const char *name, | |
156 | struct module **owner, | |
157 | const unsigned long **crc, | |
158 | int gplok) | |
159 | { | |
160 | struct module *mod; | |
3fd6805f | 161 | const struct kernel_symbol *ks; |
1da177e4 LT |
162 | |
163 | /* Core kernel first. */ | |
164 | *owner = NULL; | |
3fd6805f SR |
165 | ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab); |
166 | if (ks) { | |
167 | *crc = symversion(__start___kcrctab, (ks - __start___ksymtab)); | |
168 | return ks->value; | |
1da177e4 LT |
169 | } |
170 | if (gplok) { | |
3fd6805f SR |
171 | ks = lookup_symbol(name, __start___ksymtab_gpl, |
172 | __stop___ksymtab_gpl); | |
173 | if (ks) { | |
174 | *crc = symversion(__start___kcrctab_gpl, | |
175 | (ks - __start___ksymtab_gpl)); | |
176 | return ks->value; | |
177 | } | |
1da177e4 | 178 | } |
9f28bb7e GKH |
179 | ks = lookup_symbol(name, __start___ksymtab_gpl_future, |
180 | __stop___ksymtab_gpl_future); | |
181 | if (ks) { | |
182 | if (!gplok) { | |
183 | printk(KERN_WARNING "Symbol %s is being used " | |
184 | "by a non-GPL module, which will not " | |
185 | "be allowed in the future\n", name); | |
186 | printk(KERN_WARNING "Please see the file " | |
187 | "Documentation/feature-removal-schedule.txt " | |
188 | "in the kernel source tree for more " | |
189 | "details.\n"); | |
190 | } | |
191 | *crc = symversion(__start___kcrctab_gpl_future, | |
192 | (ks - __start___ksymtab_gpl_future)); | |
193 | return ks->value; | |
194 | } | |
1da177e4 LT |
195 | |
196 | /* Now try modules. */ | |
197 | list_for_each_entry(mod, &modules, list) { | |
198 | *owner = mod; | |
3fd6805f SR |
199 | ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms); |
200 | if (ks) { | |
201 | *crc = symversion(mod->crcs, (ks - mod->syms)); | |
202 | return ks->value; | |
203 | } | |
1da177e4 LT |
204 | |
205 | if (gplok) { | |
3fd6805f SR |
206 | ks = lookup_symbol(name, mod->gpl_syms, |
207 | mod->gpl_syms + mod->num_gpl_syms); | |
208 | if (ks) { | |
209 | *crc = symversion(mod->gpl_crcs, | |
210 | (ks - mod->gpl_syms)); | |
211 | return ks->value; | |
1da177e4 LT |
212 | } |
213 | } | |
9f28bb7e GKH |
214 | ks = lookup_symbol(name, mod->gpl_future_syms, |
215 | (mod->gpl_future_syms + | |
216 | mod->num_gpl_future_syms)); | |
217 | if (ks) { | |
218 | if (!gplok) { | |
219 | printk(KERN_WARNING "Symbol %s is being used " | |
220 | "by a non-GPL module, which will not " | |
221 | "be allowed in the future\n", name); | |
222 | printk(KERN_WARNING "Please see the file " | |
223 | "Documentation/feature-removal-schedule.txt " | |
224 | "in the kernel source tree for more " | |
225 | "details.\n"); | |
226 | } | |
227 | *crc = symversion(mod->gpl_future_crcs, | |
228 | (ks - mod->gpl_future_syms)); | |
229 | return ks->value; | |
230 | } | |
1da177e4 LT |
231 | } |
232 | DEBUGP("Failed to find symbol %s\n", name); | |
233 | return 0; | |
234 | } | |
235 | ||
1da177e4 LT |
236 | /* Search for module by name: must hold module_mutex. */ |
237 | static struct module *find_module(const char *name) | |
238 | { | |
239 | struct module *mod; | |
240 | ||
241 | list_for_each_entry(mod, &modules, list) { | |
242 | if (strcmp(mod->name, name) == 0) | |
243 | return mod; | |
244 | } | |
245 | return NULL; | |
246 | } | |
247 | ||
248 | #ifdef CONFIG_SMP | |
249 | /* Number of blocks used and allocated. */ | |
250 | static unsigned int pcpu_num_used, pcpu_num_allocated; | |
251 | /* Size of each block. -ve means used. */ | |
252 | static int *pcpu_size; | |
253 | ||
254 | static int split_block(unsigned int i, unsigned short size) | |
255 | { | |
256 | /* Reallocation required? */ | |
257 | if (pcpu_num_used + 1 > pcpu_num_allocated) { | |
258 | int *new = kmalloc(sizeof(new[0]) * pcpu_num_allocated*2, | |
259 | GFP_KERNEL); | |
260 | if (!new) | |
261 | return 0; | |
262 | ||
263 | memcpy(new, pcpu_size, sizeof(new[0])*pcpu_num_allocated); | |
264 | pcpu_num_allocated *= 2; | |
265 | kfree(pcpu_size); | |
266 | pcpu_size = new; | |
267 | } | |
268 | ||
269 | /* Insert a new subblock */ | |
270 | memmove(&pcpu_size[i+1], &pcpu_size[i], | |
271 | sizeof(pcpu_size[0]) * (pcpu_num_used - i)); | |
272 | pcpu_num_used++; | |
273 | ||
274 | pcpu_size[i+1] -= size; | |
275 | pcpu_size[i] = size; | |
276 | return 1; | |
277 | } | |
278 | ||
279 | static inline unsigned int block_size(int val) | |
280 | { | |
281 | if (val < 0) | |
282 | return -val; | |
283 | return val; | |
284 | } | |
285 | ||
286 | /* Created by linker magic */ | |
287 | extern char __per_cpu_start[], __per_cpu_end[]; | |
288 | ||
842bbaaa RR |
289 | static void *percpu_modalloc(unsigned long size, unsigned long align, |
290 | const char *name) | |
1da177e4 LT |
291 | { |
292 | unsigned long extra; | |
293 | unsigned int i; | |
294 | void *ptr; | |
295 | ||
842bbaaa RR |
296 | if (align > SMP_CACHE_BYTES) { |
297 | printk(KERN_WARNING "%s: per-cpu alignment %li > %i\n", | |
298 | name, align, SMP_CACHE_BYTES); | |
299 | align = SMP_CACHE_BYTES; | |
300 | } | |
1da177e4 LT |
301 | |
302 | ptr = __per_cpu_start; | |
303 | for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) { | |
304 | /* Extra for alignment requirement. */ | |
305 | extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr; | |
306 | BUG_ON(i == 0 && extra != 0); | |
307 | ||
308 | if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size) | |
309 | continue; | |
310 | ||
311 | /* Transfer extra to previous block. */ | |
312 | if (pcpu_size[i-1] < 0) | |
313 | pcpu_size[i-1] -= extra; | |
314 | else | |
315 | pcpu_size[i-1] += extra; | |
316 | pcpu_size[i] -= extra; | |
317 | ptr += extra; | |
318 | ||
319 | /* Split block if warranted */ | |
320 | if (pcpu_size[i] - size > sizeof(unsigned long)) | |
321 | if (!split_block(i, size)) | |
322 | return NULL; | |
323 | ||
324 | /* Mark allocated */ | |
325 | pcpu_size[i] = -pcpu_size[i]; | |
326 | return ptr; | |
327 | } | |
328 | ||
329 | printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n", | |
330 | size); | |
331 | return NULL; | |
332 | } | |
333 | ||
334 | static void percpu_modfree(void *freeme) | |
335 | { | |
336 | unsigned int i; | |
337 | void *ptr = __per_cpu_start + block_size(pcpu_size[0]); | |
338 | ||
339 | /* First entry is core kernel percpu data. */ | |
340 | for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) { | |
341 | if (ptr == freeme) { | |
342 | pcpu_size[i] = -pcpu_size[i]; | |
343 | goto free; | |
344 | } | |
345 | } | |
346 | BUG(); | |
347 | ||
348 | free: | |
349 | /* Merge with previous? */ | |
350 | if (pcpu_size[i-1] >= 0) { | |
351 | pcpu_size[i-1] += pcpu_size[i]; | |
352 | pcpu_num_used--; | |
353 | memmove(&pcpu_size[i], &pcpu_size[i+1], | |
354 | (pcpu_num_used - i) * sizeof(pcpu_size[0])); | |
355 | i--; | |
356 | } | |
357 | /* Merge with next? */ | |
358 | if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) { | |
359 | pcpu_size[i] += pcpu_size[i+1]; | |
360 | pcpu_num_used--; | |
361 | memmove(&pcpu_size[i+1], &pcpu_size[i+2], | |
362 | (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0])); | |
363 | } | |
364 | } | |
365 | ||
366 | static unsigned int find_pcpusec(Elf_Ehdr *hdr, | |
367 | Elf_Shdr *sechdrs, | |
368 | const char *secstrings) | |
369 | { | |
370 | return find_sec(hdr, sechdrs, secstrings, ".data.percpu"); | |
371 | } | |
372 | ||
373 | static int percpu_modinit(void) | |
374 | { | |
375 | pcpu_num_used = 2; | |
376 | pcpu_num_allocated = 2; | |
377 | pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated, | |
378 | GFP_KERNEL); | |
379 | /* Static in-kernel percpu data (used). */ | |
380 | pcpu_size[0] = -ALIGN(__per_cpu_end-__per_cpu_start, SMP_CACHE_BYTES); | |
381 | /* Free room. */ | |
382 | pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0]; | |
383 | if (pcpu_size[1] < 0) { | |
384 | printk(KERN_ERR "No per-cpu room for modules.\n"); | |
385 | pcpu_num_used = 1; | |
386 | } | |
387 | ||
388 | return 0; | |
389 | } | |
390 | __initcall(percpu_modinit); | |
391 | #else /* ... !CONFIG_SMP */ | |
842bbaaa RR |
392 | static inline void *percpu_modalloc(unsigned long size, unsigned long align, |
393 | const char *name) | |
1da177e4 LT |
394 | { |
395 | return NULL; | |
396 | } | |
397 | static inline void percpu_modfree(void *pcpuptr) | |
398 | { | |
399 | BUG(); | |
400 | } | |
401 | static inline unsigned int find_pcpusec(Elf_Ehdr *hdr, | |
402 | Elf_Shdr *sechdrs, | |
403 | const char *secstrings) | |
404 | { | |
405 | return 0; | |
406 | } | |
407 | static inline void percpu_modcopy(void *pcpudst, const void *src, | |
408 | unsigned long size) | |
409 | { | |
410 | /* pcpusec should be 0, and size of that section should be 0. */ | |
411 | BUG_ON(size != 0); | |
412 | } | |
413 | #endif /* CONFIG_SMP */ | |
414 | ||
c988d2b2 MD |
415 | #define MODINFO_ATTR(field) \ |
416 | static void setup_modinfo_##field(struct module *mod, const char *s) \ | |
417 | { \ | |
418 | mod->field = kstrdup(s, GFP_KERNEL); \ | |
419 | } \ | |
420 | static ssize_t show_modinfo_##field(struct module_attribute *mattr, \ | |
421 | struct module *mod, char *buffer) \ | |
422 | { \ | |
423 | return sprintf(buffer, "%s\n", mod->field); \ | |
424 | } \ | |
425 | static int modinfo_##field##_exists(struct module *mod) \ | |
426 | { \ | |
427 | return mod->field != NULL; \ | |
428 | } \ | |
429 | static void free_modinfo_##field(struct module *mod) \ | |
430 | { \ | |
431 | kfree(mod->field); \ | |
432 | mod->field = NULL; \ | |
433 | } \ | |
434 | static struct module_attribute modinfo_##field = { \ | |
435 | .attr = { .name = __stringify(field), .mode = 0444, \ | |
436 | .owner = THIS_MODULE }, \ | |
437 | .show = show_modinfo_##field, \ | |
438 | .setup = setup_modinfo_##field, \ | |
439 | .test = modinfo_##field##_exists, \ | |
440 | .free = free_modinfo_##field, \ | |
441 | }; | |
442 | ||
443 | MODINFO_ATTR(version); | |
444 | MODINFO_ATTR(srcversion); | |
445 | ||
03e88ae1 | 446 | #ifdef CONFIG_MODULE_UNLOAD |
1da177e4 LT |
447 | /* Init the unload section of the module. */ |
448 | static void module_unload_init(struct module *mod) | |
449 | { | |
450 | unsigned int i; | |
451 | ||
452 | INIT_LIST_HEAD(&mod->modules_which_use_me); | |
453 | for (i = 0; i < NR_CPUS; i++) | |
454 | local_set(&mod->ref[i].count, 0); | |
455 | /* Hold reference count during initialization. */ | |
39c715b7 | 456 | local_set(&mod->ref[raw_smp_processor_id()].count, 1); |
1da177e4 LT |
457 | /* Backwards compatibility macros put refcount during init. */ |
458 | mod->waiter = current; | |
459 | } | |
460 | ||
461 | /* modules using other modules */ | |
462 | struct module_use | |
463 | { | |
464 | struct list_head list; | |
465 | struct module *module_which_uses; | |
466 | }; | |
467 | ||
468 | /* Does a already use b? */ | |
469 | static int already_uses(struct module *a, struct module *b) | |
470 | { | |
471 | struct module_use *use; | |
472 | ||
473 | list_for_each_entry(use, &b->modules_which_use_me, list) { | |
474 | if (use->module_which_uses == a) { | |
475 | DEBUGP("%s uses %s!\n", a->name, b->name); | |
476 | return 1; | |
477 | } | |
478 | } | |
479 | DEBUGP("%s does not use %s!\n", a->name, b->name); | |
480 | return 0; | |
481 | } | |
482 | ||
483 | /* Module a uses b */ | |
484 | static int use_module(struct module *a, struct module *b) | |
485 | { | |
486 | struct module_use *use; | |
487 | if (b == NULL || already_uses(a, b)) return 1; | |
488 | ||
489 | if (!strong_try_module_get(b)) | |
490 | return 0; | |
491 | ||
492 | DEBUGP("Allocating new usage for %s.\n", a->name); | |
493 | use = kmalloc(sizeof(*use), GFP_ATOMIC); | |
494 | if (!use) { | |
495 | printk("%s: out of memory loading\n", a->name); | |
496 | module_put(b); | |
497 | return 0; | |
498 | } | |
499 | ||
500 | use->module_which_uses = a; | |
501 | list_add(&use->list, &b->modules_which_use_me); | |
502 | return 1; | |
503 | } | |
504 | ||
505 | /* Clear the unload stuff of the module. */ | |
506 | static void module_unload_free(struct module *mod) | |
507 | { | |
508 | struct module *i; | |
509 | ||
510 | list_for_each_entry(i, &modules, list) { | |
511 | struct module_use *use; | |
512 | ||
513 | list_for_each_entry(use, &i->modules_which_use_me, list) { | |
514 | if (use->module_which_uses == mod) { | |
515 | DEBUGP("%s unusing %s\n", mod->name, i->name); | |
516 | module_put(i); | |
517 | list_del(&use->list); | |
518 | kfree(use); | |
519 | /* There can be at most one match. */ | |
520 | break; | |
521 | } | |
522 | } | |
523 | } | |
524 | } | |
525 | ||
526 | #ifdef CONFIG_MODULE_FORCE_UNLOAD | |
fb169793 | 527 | static inline int try_force_unload(unsigned int flags) |
1da177e4 LT |
528 | { |
529 | int ret = (flags & O_TRUNC); | |
530 | if (ret) | |
fb169793 | 531 | add_taint(TAINT_FORCED_RMMOD); |
1da177e4 LT |
532 | return ret; |
533 | } | |
534 | #else | |
fb169793 | 535 | static inline int try_force_unload(unsigned int flags) |
1da177e4 LT |
536 | { |
537 | return 0; | |
538 | } | |
539 | #endif /* CONFIG_MODULE_FORCE_UNLOAD */ | |
540 | ||
541 | struct stopref | |
542 | { | |
543 | struct module *mod; | |
544 | int flags; | |
545 | int *forced; | |
546 | }; | |
547 | ||
548 | /* Whole machine is stopped with interrupts off when this runs. */ | |
549 | static int __try_stop_module(void *_sref) | |
550 | { | |
551 | struct stopref *sref = _sref; | |
552 | ||
553 | /* If it's not unused, quit unless we are told to block. */ | |
554 | if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) { | |
fb169793 | 555 | if (!(*sref->forced = try_force_unload(sref->flags))) |
1da177e4 LT |
556 | return -EWOULDBLOCK; |
557 | } | |
558 | ||
559 | /* Mark it as dying. */ | |
560 | sref->mod->state = MODULE_STATE_GOING; | |
561 | return 0; | |
562 | } | |
563 | ||
564 | static int try_stop_module(struct module *mod, int flags, int *forced) | |
565 | { | |
566 | struct stopref sref = { mod, flags, forced }; | |
567 | ||
568 | return stop_machine_run(__try_stop_module, &sref, NR_CPUS); | |
569 | } | |
570 | ||
571 | unsigned int module_refcount(struct module *mod) | |
572 | { | |
573 | unsigned int i, total = 0; | |
574 | ||
575 | for (i = 0; i < NR_CPUS; i++) | |
576 | total += local_read(&mod->ref[i].count); | |
577 | return total; | |
578 | } | |
579 | EXPORT_SYMBOL(module_refcount); | |
580 | ||
581 | /* This exists whether we can unload or not */ | |
582 | static void free_module(struct module *mod); | |
583 | ||
584 | static void wait_for_zero_refcount(struct module *mod) | |
585 | { | |
586 | /* Since we might sleep for some time, drop the semaphore first */ | |
6389a385 | 587 | mutex_unlock(&module_mutex); |
1da177e4 LT |
588 | for (;;) { |
589 | DEBUGP("Looking at refcount...\n"); | |
590 | set_current_state(TASK_UNINTERRUPTIBLE); | |
591 | if (module_refcount(mod) == 0) | |
592 | break; | |
593 | schedule(); | |
594 | } | |
595 | current->state = TASK_RUNNING; | |
6389a385 | 596 | mutex_lock(&module_mutex); |
1da177e4 LT |
597 | } |
598 | ||
599 | asmlinkage long | |
600 | sys_delete_module(const char __user *name_user, unsigned int flags) | |
601 | { | |
602 | struct module *mod; | |
603 | char name[MODULE_NAME_LEN]; | |
604 | int ret, forced = 0; | |
605 | ||
606 | if (!capable(CAP_SYS_MODULE)) | |
607 | return -EPERM; | |
608 | ||
609 | if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0) | |
610 | return -EFAULT; | |
611 | name[MODULE_NAME_LEN-1] = '\0'; | |
612 | ||
6389a385 | 613 | if (mutex_lock_interruptible(&module_mutex) != 0) |
1da177e4 LT |
614 | return -EINTR; |
615 | ||
616 | mod = find_module(name); | |
617 | if (!mod) { | |
618 | ret = -ENOENT; | |
619 | goto out; | |
620 | } | |
621 | ||
622 | if (!list_empty(&mod->modules_which_use_me)) { | |
623 | /* Other modules depend on us: get rid of them first. */ | |
624 | ret = -EWOULDBLOCK; | |
625 | goto out; | |
626 | } | |
627 | ||
628 | /* Doing init or already dying? */ | |
629 | if (mod->state != MODULE_STATE_LIVE) { | |
630 | /* FIXME: if (force), slam module count and wake up | |
631 | waiter --RR */ | |
632 | DEBUGP("%s already dying\n", mod->name); | |
633 | ret = -EBUSY; | |
634 | goto out; | |
635 | } | |
636 | ||
637 | /* If it has an init func, it must have an exit func to unload */ | |
638 | if ((mod->init != NULL && mod->exit == NULL) | |
639 | || mod->unsafe) { | |
fb169793 | 640 | forced = try_force_unload(flags); |
1da177e4 LT |
641 | if (!forced) { |
642 | /* This module can't be removed */ | |
643 | ret = -EBUSY; | |
644 | goto out; | |
645 | } | |
646 | } | |
647 | ||
648 | /* Set this up before setting mod->state */ | |
649 | mod->waiter = current; | |
650 | ||
651 | /* Stop the machine so refcounts can't move and disable module. */ | |
652 | ret = try_stop_module(mod, flags, &forced); | |
653 | if (ret != 0) | |
654 | goto out; | |
655 | ||
656 | /* Never wait if forced. */ | |
657 | if (!forced && module_refcount(mod) != 0) | |
658 | wait_for_zero_refcount(mod); | |
659 | ||
660 | /* Final destruction now noone is using it. */ | |
661 | if (mod->exit != NULL) { | |
6389a385 | 662 | mutex_unlock(&module_mutex); |
1da177e4 | 663 | mod->exit(); |
6389a385 | 664 | mutex_lock(&module_mutex); |
1da177e4 LT |
665 | } |
666 | free_module(mod); | |
667 | ||
668 | out: | |
6389a385 | 669 | mutex_unlock(&module_mutex); |
1da177e4 LT |
670 | return ret; |
671 | } | |
672 | ||
673 | static void print_unload_info(struct seq_file *m, struct module *mod) | |
674 | { | |
675 | struct module_use *use; | |
676 | int printed_something = 0; | |
677 | ||
678 | seq_printf(m, " %u ", module_refcount(mod)); | |
679 | ||
680 | /* Always include a trailing , so userspace can differentiate | |
681 | between this and the old multi-field proc format. */ | |
682 | list_for_each_entry(use, &mod->modules_which_use_me, list) { | |
683 | printed_something = 1; | |
684 | seq_printf(m, "%s,", use->module_which_uses->name); | |
685 | } | |
686 | ||
687 | if (mod->unsafe) { | |
688 | printed_something = 1; | |
689 | seq_printf(m, "[unsafe],"); | |
690 | } | |
691 | ||
692 | if (mod->init != NULL && mod->exit == NULL) { | |
693 | printed_something = 1; | |
694 | seq_printf(m, "[permanent],"); | |
695 | } | |
696 | ||
697 | if (!printed_something) | |
698 | seq_printf(m, "-"); | |
699 | } | |
700 | ||
701 | void __symbol_put(const char *symbol) | |
702 | { | |
703 | struct module *owner; | |
704 | unsigned long flags; | |
705 | const unsigned long *crc; | |
706 | ||
707 | spin_lock_irqsave(&modlist_lock, flags); | |
708 | if (!__find_symbol(symbol, &owner, &crc, 1)) | |
709 | BUG(); | |
710 | module_put(owner); | |
711 | spin_unlock_irqrestore(&modlist_lock, flags); | |
712 | } | |
713 | EXPORT_SYMBOL(__symbol_put); | |
714 | ||
715 | void symbol_put_addr(void *addr) | |
716 | { | |
717 | unsigned long flags; | |
718 | ||
719 | spin_lock_irqsave(&modlist_lock, flags); | |
720 | if (!kernel_text_address((unsigned long)addr)) | |
721 | BUG(); | |
722 | ||
723 | module_put(module_text_address((unsigned long)addr)); | |
724 | spin_unlock_irqrestore(&modlist_lock, flags); | |
725 | } | |
726 | EXPORT_SYMBOL_GPL(symbol_put_addr); | |
727 | ||
728 | static ssize_t show_refcnt(struct module_attribute *mattr, | |
729 | struct module *mod, char *buffer) | |
730 | { | |
731 | /* sysfs holds a reference */ | |
732 | return sprintf(buffer, "%u\n", module_refcount(mod)-1); | |
733 | } | |
734 | ||
735 | static struct module_attribute refcnt = { | |
736 | .attr = { .name = "refcnt", .mode = 0444, .owner = THIS_MODULE }, | |
737 | .show = show_refcnt, | |
738 | }; | |
739 | ||
740 | #else /* !CONFIG_MODULE_UNLOAD */ | |
741 | static void print_unload_info(struct seq_file *m, struct module *mod) | |
742 | { | |
743 | /* We don't know the usage count, or what modules are using. */ | |
744 | seq_printf(m, " - -"); | |
745 | } | |
746 | ||
747 | static inline void module_unload_free(struct module *mod) | |
748 | { | |
749 | } | |
750 | ||
751 | static inline int use_module(struct module *a, struct module *b) | |
752 | { | |
753 | return strong_try_module_get(b); | |
754 | } | |
755 | ||
756 | static inline void module_unload_init(struct module *mod) | |
757 | { | |
758 | } | |
759 | #endif /* CONFIG_MODULE_UNLOAD */ | |
760 | ||
03e88ae1 GKH |
761 | static struct module_attribute *modinfo_attrs[] = { |
762 | &modinfo_version, | |
763 | &modinfo_srcversion, | |
764 | #ifdef CONFIG_MODULE_UNLOAD | |
765 | &refcnt, | |
766 | #endif | |
767 | NULL, | |
768 | }; | |
769 | ||
1da177e4 LT |
770 | static const char vermagic[] = VERMAGIC_STRING; |
771 | ||
772 | #ifdef CONFIG_MODVERSIONS | |
773 | static int check_version(Elf_Shdr *sechdrs, | |
774 | unsigned int versindex, | |
775 | const char *symname, | |
776 | struct module *mod, | |
777 | const unsigned long *crc) | |
778 | { | |
779 | unsigned int i, num_versions; | |
780 | struct modversion_info *versions; | |
781 | ||
782 | /* Exporting module didn't supply crcs? OK, we're already tainted. */ | |
783 | if (!crc) | |
784 | return 1; | |
785 | ||
786 | versions = (void *) sechdrs[versindex].sh_addr; | |
787 | num_versions = sechdrs[versindex].sh_size | |
788 | / sizeof(struct modversion_info); | |
789 | ||
790 | for (i = 0; i < num_versions; i++) { | |
791 | if (strcmp(versions[i].name, symname) != 0) | |
792 | continue; | |
793 | ||
794 | if (versions[i].crc == *crc) | |
795 | return 1; | |
796 | printk("%s: disagrees about version of symbol %s\n", | |
797 | mod->name, symname); | |
798 | DEBUGP("Found checksum %lX vs module %lX\n", | |
799 | *crc, versions[i].crc); | |
800 | return 0; | |
801 | } | |
802 | /* Not in module's version table. OK, but that taints the kernel. */ | |
803 | if (!(tainted & TAINT_FORCED_MODULE)) { | |
804 | printk("%s: no version for \"%s\" found: kernel tainted.\n", | |
805 | mod->name, symname); | |
9f158333 | 806 | add_taint(TAINT_FORCED_MODULE); |
1da177e4 LT |
807 | } |
808 | return 1; | |
809 | } | |
810 | ||
811 | static inline int check_modstruct_version(Elf_Shdr *sechdrs, | |
812 | unsigned int versindex, | |
813 | struct module *mod) | |
814 | { | |
815 | const unsigned long *crc; | |
816 | struct module *owner; | |
817 | ||
818 | if (!__find_symbol("struct_module", &owner, &crc, 1)) | |
819 | BUG(); | |
820 | return check_version(sechdrs, versindex, "struct_module", mod, | |
821 | crc); | |
822 | } | |
823 | ||
824 | /* First part is kernel version, which we ignore. */ | |
825 | static inline int same_magic(const char *amagic, const char *bmagic) | |
826 | { | |
827 | amagic += strcspn(amagic, " "); | |
828 | bmagic += strcspn(bmagic, " "); | |
829 | return strcmp(amagic, bmagic) == 0; | |
830 | } | |
831 | #else | |
832 | static inline int check_version(Elf_Shdr *sechdrs, | |
833 | unsigned int versindex, | |
834 | const char *symname, | |
835 | struct module *mod, | |
836 | const unsigned long *crc) | |
837 | { | |
838 | return 1; | |
839 | } | |
840 | ||
841 | static inline int check_modstruct_version(Elf_Shdr *sechdrs, | |
842 | unsigned int versindex, | |
843 | struct module *mod) | |
844 | { | |
845 | return 1; | |
846 | } | |
847 | ||
848 | static inline int same_magic(const char *amagic, const char *bmagic) | |
849 | { | |
850 | return strcmp(amagic, bmagic) == 0; | |
851 | } | |
852 | #endif /* CONFIG_MODVERSIONS */ | |
853 | ||
854 | /* Resolve a symbol for this module. I.e. if we find one, record usage. | |
855 | Must be holding module_mutex. */ | |
856 | static unsigned long resolve_symbol(Elf_Shdr *sechdrs, | |
857 | unsigned int versindex, | |
858 | const char *name, | |
859 | struct module *mod) | |
860 | { | |
861 | struct module *owner; | |
862 | unsigned long ret; | |
863 | const unsigned long *crc; | |
864 | ||
1da177e4 LT |
865 | ret = __find_symbol(name, &owner, &crc, mod->license_gplok); |
866 | if (ret) { | |
867 | /* use_module can fail due to OOM, or module unloading */ | |
868 | if (!check_version(sechdrs, versindex, name, mod, crc) || | |
869 | !use_module(mod, owner)) | |
870 | ret = 0; | |
871 | } | |
1da177e4 LT |
872 | return ret; |
873 | } | |
874 | ||
875 | ||
876 | /* | |
877 | * /sys/module/foo/sections stuff | |
878 | * J. Corbet <corbet@lwn.net> | |
879 | */ | |
880 | #ifdef CONFIG_KALLSYMS | |
881 | static ssize_t module_sect_show(struct module_attribute *mattr, | |
882 | struct module *mod, char *buf) | |
883 | { | |
884 | struct module_sect_attr *sattr = | |
885 | container_of(mattr, struct module_sect_attr, mattr); | |
886 | return sprintf(buf, "0x%lx\n", sattr->address); | |
887 | } | |
888 | ||
889 | static void add_sect_attrs(struct module *mod, unsigned int nsect, | |
890 | char *secstrings, Elf_Shdr *sechdrs) | |
891 | { | |
892 | unsigned int nloaded = 0, i, size[2]; | |
893 | struct module_sect_attrs *sect_attrs; | |
894 | struct module_sect_attr *sattr; | |
895 | struct attribute **gattr; | |
896 | ||
897 | /* Count loaded sections and allocate structures */ | |
898 | for (i = 0; i < nsect; i++) | |
899 | if (sechdrs[i].sh_flags & SHF_ALLOC) | |
900 | nloaded++; | |
901 | size[0] = ALIGN(sizeof(*sect_attrs) | |
902 | + nloaded * sizeof(sect_attrs->attrs[0]), | |
903 | sizeof(sect_attrs->grp.attrs[0])); | |
904 | size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]); | |
905 | if (! (sect_attrs = kmalloc(size[0] + size[1], GFP_KERNEL))) | |
906 | return; | |
907 | ||
908 | /* Setup section attributes. */ | |
909 | sect_attrs->grp.name = "sections"; | |
910 | sect_attrs->grp.attrs = (void *)sect_attrs + size[0]; | |
911 | ||
912 | sattr = §_attrs->attrs[0]; | |
913 | gattr = §_attrs->grp.attrs[0]; | |
914 | for (i = 0; i < nsect; i++) { | |
915 | if (! (sechdrs[i].sh_flags & SHF_ALLOC)) | |
916 | continue; | |
917 | sattr->address = sechdrs[i].sh_addr; | |
918 | strlcpy(sattr->name, secstrings + sechdrs[i].sh_name, | |
919 | MODULE_SECT_NAME_LEN); | |
920 | sattr->mattr.show = module_sect_show; | |
921 | sattr->mattr.store = NULL; | |
922 | sattr->mattr.attr.name = sattr->name; | |
923 | sattr->mattr.attr.owner = mod; | |
924 | sattr->mattr.attr.mode = S_IRUGO; | |
925 | *(gattr++) = &(sattr++)->mattr.attr; | |
926 | } | |
927 | *gattr = NULL; | |
928 | ||
929 | if (sysfs_create_group(&mod->mkobj.kobj, §_attrs->grp)) | |
930 | goto out; | |
931 | ||
932 | mod->sect_attrs = sect_attrs; | |
933 | return; | |
934 | out: | |
935 | kfree(sect_attrs); | |
936 | } | |
937 | ||
938 | static void remove_sect_attrs(struct module *mod) | |
939 | { | |
940 | if (mod->sect_attrs) { | |
941 | sysfs_remove_group(&mod->mkobj.kobj, | |
942 | &mod->sect_attrs->grp); | |
943 | /* We are positive that no one is using any sect attrs | |
944 | * at this point. Deallocate immediately. */ | |
945 | kfree(mod->sect_attrs); | |
946 | mod->sect_attrs = NULL; | |
947 | } | |
948 | } | |
949 | ||
950 | ||
951 | #else | |
952 | static inline void add_sect_attrs(struct module *mod, unsigned int nsect, | |
953 | char *sectstrings, Elf_Shdr *sechdrs) | |
954 | { | |
955 | } | |
956 | ||
957 | static inline void remove_sect_attrs(struct module *mod) | |
958 | { | |
959 | } | |
960 | #endif /* CONFIG_KALLSYMS */ | |
961 | ||
c988d2b2 MD |
962 | static int module_add_modinfo_attrs(struct module *mod) |
963 | { | |
964 | struct module_attribute *attr; | |
03e88ae1 | 965 | struct module_attribute *temp_attr; |
c988d2b2 MD |
966 | int error = 0; |
967 | int i; | |
968 | ||
03e88ae1 GKH |
969 | mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) * |
970 | (ARRAY_SIZE(modinfo_attrs) + 1)), | |
971 | GFP_KERNEL); | |
972 | if (!mod->modinfo_attrs) | |
973 | return -ENOMEM; | |
974 | ||
975 | temp_attr = mod->modinfo_attrs; | |
c988d2b2 MD |
976 | for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) { |
977 | if (!attr->test || | |
03e88ae1 GKH |
978 | (attr->test && attr->test(mod))) { |
979 | memcpy(temp_attr, attr, sizeof(*temp_attr)); | |
980 | temp_attr->attr.owner = mod; | |
981 | error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr); | |
982 | ++temp_attr; | |
983 | } | |
c988d2b2 MD |
984 | } |
985 | return error; | |
986 | } | |
987 | ||
988 | static void module_remove_modinfo_attrs(struct module *mod) | |
989 | { | |
990 | struct module_attribute *attr; | |
991 | int i; | |
992 | ||
03e88ae1 GKH |
993 | for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { |
994 | /* pick a field to test for end of list */ | |
995 | if (!attr->attr.name) | |
996 | break; | |
c988d2b2 | 997 | sysfs_remove_file(&mod->mkobj.kobj,&attr->attr); |
03e88ae1 GKH |
998 | if (attr->free) |
999 | attr->free(mod); | |
c988d2b2 | 1000 | } |
03e88ae1 | 1001 | kfree(mod->modinfo_attrs); |
c988d2b2 | 1002 | } |
1da177e4 LT |
1003 | |
1004 | static int mod_sysfs_setup(struct module *mod, | |
1005 | struct kernel_param *kparam, | |
1006 | unsigned int num_params) | |
1007 | { | |
1008 | int err; | |
1009 | ||
1010 | memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); | |
1011 | err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name); | |
1012 | if (err) | |
1013 | goto out; | |
1014 | kobj_set_kset_s(&mod->mkobj, module_subsys); | |
1015 | mod->mkobj.mod = mod; | |
1016 | err = kobject_register(&mod->mkobj.kobj); | |
1017 | if (err) | |
1018 | goto out; | |
1019 | ||
1da177e4 LT |
1020 | err = module_param_sysfs_setup(mod, kparam, num_params); |
1021 | if (err) | |
1022 | goto out_unreg; | |
1023 | ||
c988d2b2 MD |
1024 | err = module_add_modinfo_attrs(mod); |
1025 | if (err) | |
1026 | goto out_unreg; | |
c988d2b2 | 1027 | |
1da177e4 LT |
1028 | return 0; |
1029 | ||
1030 | out_unreg: | |
1031 | kobject_unregister(&mod->mkobj.kobj); | |
1032 | out: | |
1033 | return err; | |
1034 | } | |
1035 | ||
1036 | static void mod_kobject_remove(struct module *mod) | |
1037 | { | |
c988d2b2 | 1038 | module_remove_modinfo_attrs(mod); |
1da177e4 LT |
1039 | module_param_sysfs_remove(mod); |
1040 | ||
1041 | kobject_unregister(&mod->mkobj.kobj); | |
1042 | } | |
1043 | ||
1044 | /* | |
1045 | * unlink the module with the whole machine is stopped with interrupts off | |
1046 | * - this defends against kallsyms not taking locks | |
1047 | */ | |
1048 | static int __unlink_module(void *_mod) | |
1049 | { | |
1050 | struct module *mod = _mod; | |
1051 | list_del(&mod->list); | |
1052 | return 0; | |
1053 | } | |
1054 | ||
1055 | /* Free a module, remove from lists, etc (must hold module mutex). */ | |
1056 | static void free_module(struct module *mod) | |
1057 | { | |
1058 | /* Delete from various lists */ | |
1059 | stop_machine_run(__unlink_module, mod, NR_CPUS); | |
1060 | remove_sect_attrs(mod); | |
1061 | mod_kobject_remove(mod); | |
1062 | ||
1063 | /* Arch-specific cleanup. */ | |
1064 | module_arch_cleanup(mod); | |
1065 | ||
1066 | /* Module unload stuff */ | |
1067 | module_unload_free(mod); | |
1068 | ||
1069 | /* This may be NULL, but that's OK */ | |
1070 | module_free(mod, mod->module_init); | |
1071 | kfree(mod->args); | |
1072 | if (mod->percpu) | |
1073 | percpu_modfree(mod->percpu); | |
1074 | ||
1075 | /* Finally, free the core (containing the module structure) */ | |
1076 | module_free(mod, mod->module_core); | |
1077 | } | |
1078 | ||
1079 | void *__symbol_get(const char *symbol) | |
1080 | { | |
1081 | struct module *owner; | |
1082 | unsigned long value, flags; | |
1083 | const unsigned long *crc; | |
1084 | ||
1085 | spin_lock_irqsave(&modlist_lock, flags); | |
1086 | value = __find_symbol(symbol, &owner, &crc, 1); | |
1087 | if (value && !strong_try_module_get(owner)) | |
1088 | value = 0; | |
1089 | spin_unlock_irqrestore(&modlist_lock, flags); | |
1090 | ||
1091 | return (void *)value; | |
1092 | } | |
1093 | EXPORT_SYMBOL_GPL(__symbol_get); | |
1094 | ||
eea8b54d AN |
1095 | /* |
1096 | * Ensure that an exported symbol [global namespace] does not already exist | |
1097 | * in the Kernel or in some other modules exported symbol table. | |
1098 | */ | |
1099 | static int verify_export_symbols(struct module *mod) | |
1100 | { | |
1101 | const char *name = NULL; | |
1102 | unsigned long i, ret = 0; | |
1103 | struct module *owner; | |
1104 | const unsigned long *crc; | |
1105 | ||
1106 | for (i = 0; i < mod->num_syms; i++) | |
1107 | if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) { | |
1108 | name = mod->syms[i].name; | |
1109 | ret = -ENOEXEC; | |
1110 | goto dup; | |
1111 | } | |
1112 | ||
1113 | for (i = 0; i < mod->num_gpl_syms; i++) | |
1114 | if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) { | |
1115 | name = mod->gpl_syms[i].name; | |
1116 | ret = -ENOEXEC; | |
1117 | goto dup; | |
1118 | } | |
1119 | ||
1120 | dup: | |
1121 | if (ret) | |
1122 | printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n", | |
1123 | mod->name, name, module_name(owner)); | |
1124 | ||
1125 | return ret; | |
1126 | } | |
1127 | ||
1da177e4 LT |
1128 | /* Change all symbols so that sh_value encodes the pointer directly. */ |
1129 | static int simplify_symbols(Elf_Shdr *sechdrs, | |
1130 | unsigned int symindex, | |
1131 | const char *strtab, | |
1132 | unsigned int versindex, | |
1133 | unsigned int pcpuindex, | |
1134 | struct module *mod) | |
1135 | { | |
1136 | Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr; | |
1137 | unsigned long secbase; | |
1138 | unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym); | |
1139 | int ret = 0; | |
1140 | ||
1141 | for (i = 1; i < n; i++) { | |
1142 | switch (sym[i].st_shndx) { | |
1143 | case SHN_COMMON: | |
1144 | /* We compiled with -fno-common. These are not | |
1145 | supposed to happen. */ | |
1146 | DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name); | |
1147 | printk("%s: please compile with -fno-common\n", | |
1148 | mod->name); | |
1149 | ret = -ENOEXEC; | |
1150 | break; | |
1151 | ||
1152 | case SHN_ABS: | |
1153 | /* Don't need to do anything */ | |
1154 | DEBUGP("Absolute symbol: 0x%08lx\n", | |
1155 | (long)sym[i].st_value); | |
1156 | break; | |
1157 | ||
1158 | case SHN_UNDEF: | |
1159 | sym[i].st_value | |
1160 | = resolve_symbol(sechdrs, versindex, | |
1161 | strtab + sym[i].st_name, mod); | |
1162 | ||
1163 | /* Ok if resolved. */ | |
1164 | if (sym[i].st_value != 0) | |
1165 | break; | |
1166 | /* Ok if weak. */ | |
1167 | if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK) | |
1168 | break; | |
1169 | ||
1170 | printk(KERN_WARNING "%s: Unknown symbol %s\n", | |
1171 | mod->name, strtab + sym[i].st_name); | |
1172 | ret = -ENOENT; | |
1173 | break; | |
1174 | ||
1175 | default: | |
1176 | /* Divert to percpu allocation if a percpu var. */ | |
1177 | if (sym[i].st_shndx == pcpuindex) | |
1178 | secbase = (unsigned long)mod->percpu; | |
1179 | else | |
1180 | secbase = sechdrs[sym[i].st_shndx].sh_addr; | |
1181 | sym[i].st_value += secbase; | |
1182 | break; | |
1183 | } | |
1184 | } | |
1185 | ||
1186 | return ret; | |
1187 | } | |
1188 | ||
1189 | /* Update size with this section: return offset. */ | |
1190 | static long get_offset(unsigned long *size, Elf_Shdr *sechdr) | |
1191 | { | |
1192 | long ret; | |
1193 | ||
1194 | ret = ALIGN(*size, sechdr->sh_addralign ?: 1); | |
1195 | *size = ret + sechdr->sh_size; | |
1196 | return ret; | |
1197 | } | |
1198 | ||
1199 | /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld | |
1200 | might -- code, read-only data, read-write data, small data. Tally | |
1201 | sizes, and place the offsets into sh_entsize fields: high bit means it | |
1202 | belongs in init. */ | |
1203 | static void layout_sections(struct module *mod, | |
1204 | const Elf_Ehdr *hdr, | |
1205 | Elf_Shdr *sechdrs, | |
1206 | const char *secstrings) | |
1207 | { | |
1208 | static unsigned long const masks[][2] = { | |
1209 | /* NOTE: all executable code must be the first section | |
1210 | * in this array; otherwise modify the text_size | |
1211 | * finder in the two loops below */ | |
1212 | { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL }, | |
1213 | { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL }, | |
1214 | { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL }, | |
1215 | { ARCH_SHF_SMALL | SHF_ALLOC, 0 } | |
1216 | }; | |
1217 | unsigned int m, i; | |
1218 | ||
1219 | for (i = 0; i < hdr->e_shnum; i++) | |
1220 | sechdrs[i].sh_entsize = ~0UL; | |
1221 | ||
1222 | DEBUGP("Core section allocation order:\n"); | |
1223 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { | |
1224 | for (i = 0; i < hdr->e_shnum; ++i) { | |
1225 | Elf_Shdr *s = &sechdrs[i]; | |
1226 | ||
1227 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
1228 | || (s->sh_flags & masks[m][1]) | |
1229 | || s->sh_entsize != ~0UL | |
1230 | || strncmp(secstrings + s->sh_name, | |
1231 | ".init", 5) == 0) | |
1232 | continue; | |
1233 | s->sh_entsize = get_offset(&mod->core_size, s); | |
1234 | DEBUGP("\t%s\n", secstrings + s->sh_name); | |
1235 | } | |
1236 | if (m == 0) | |
1237 | mod->core_text_size = mod->core_size; | |
1238 | } | |
1239 | ||
1240 | DEBUGP("Init section allocation order:\n"); | |
1241 | for (m = 0; m < ARRAY_SIZE(masks); ++m) { | |
1242 | for (i = 0; i < hdr->e_shnum; ++i) { | |
1243 | Elf_Shdr *s = &sechdrs[i]; | |
1244 | ||
1245 | if ((s->sh_flags & masks[m][0]) != masks[m][0] | |
1246 | || (s->sh_flags & masks[m][1]) | |
1247 | || s->sh_entsize != ~0UL | |
1248 | || strncmp(secstrings + s->sh_name, | |
1249 | ".init", 5) != 0) | |
1250 | continue; | |
1251 | s->sh_entsize = (get_offset(&mod->init_size, s) | |
1252 | | INIT_OFFSET_MASK); | |
1253 | DEBUGP("\t%s\n", secstrings + s->sh_name); | |
1254 | } | |
1255 | if (m == 0) | |
1256 | mod->init_text_size = mod->init_size; | |
1257 | } | |
1258 | } | |
1259 | ||
1260 | static inline int license_is_gpl_compatible(const char *license) | |
1261 | { | |
1262 | return (strcmp(license, "GPL") == 0 | |
1263 | || strcmp(license, "GPL v2") == 0 | |
1264 | || strcmp(license, "GPL and additional rights") == 0 | |
1265 | || strcmp(license, "Dual BSD/GPL") == 0 | |
1266 | || strcmp(license, "Dual MPL/GPL") == 0); | |
1267 | } | |
1268 | ||
1269 | static void set_license(struct module *mod, const char *license) | |
1270 | { | |
1271 | if (!license) | |
1272 | license = "unspecified"; | |
1273 | ||
1274 | mod->license_gplok = license_is_gpl_compatible(license); | |
1275 | if (!mod->license_gplok && !(tainted & TAINT_PROPRIETARY_MODULE)) { | |
1276 | printk(KERN_WARNING "%s: module license '%s' taints kernel.\n", | |
1277 | mod->name, license); | |
9f158333 | 1278 | add_taint(TAINT_PROPRIETARY_MODULE); |
1da177e4 LT |
1279 | } |
1280 | } | |
1281 | ||
1282 | /* Parse tag=value strings from .modinfo section */ | |
1283 | static char *next_string(char *string, unsigned long *secsize) | |
1284 | { | |
1285 | /* Skip non-zero chars */ | |
1286 | while (string[0]) { | |
1287 | string++; | |
1288 | if ((*secsize)-- <= 1) | |
1289 | return NULL; | |
1290 | } | |
1291 | ||
1292 | /* Skip any zero padding. */ | |
1293 | while (!string[0]) { | |
1294 | string++; | |
1295 | if ((*secsize)-- <= 1) | |
1296 | return NULL; | |
1297 | } | |
1298 | return string; | |
1299 | } | |
1300 | ||
1301 | static char *get_modinfo(Elf_Shdr *sechdrs, | |
1302 | unsigned int info, | |
1303 | const char *tag) | |
1304 | { | |
1305 | char *p; | |
1306 | unsigned int taglen = strlen(tag); | |
1307 | unsigned long size = sechdrs[info].sh_size; | |
1308 | ||
1309 | for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) { | |
1310 | if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') | |
1311 | return p + taglen + 1; | |
1312 | } | |
1313 | return NULL; | |
1314 | } | |
1315 | ||
c988d2b2 MD |
1316 | static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs, |
1317 | unsigned int infoindex) | |
1318 | { | |
1319 | struct module_attribute *attr; | |
1320 | int i; | |
1321 | ||
1322 | for (i = 0; (attr = modinfo_attrs[i]); i++) { | |
1323 | if (attr->setup) | |
1324 | attr->setup(mod, | |
1325 | get_modinfo(sechdrs, | |
1326 | infoindex, | |
1327 | attr->attr.name)); | |
1328 | } | |
1329 | } | |
c988d2b2 | 1330 | |
1da177e4 LT |
1331 | #ifdef CONFIG_KALLSYMS |
1332 | int is_exported(const char *name, const struct module *mod) | |
1333 | { | |
3fd6805f SR |
1334 | if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab)) |
1335 | return 1; | |
1336 | else | |
1337 | if (lookup_symbol(name, mod->syms, mod->syms + mod->num_syms)) | |
1da177e4 | 1338 | return 1; |
3fd6805f SR |
1339 | else |
1340 | return 0; | |
1da177e4 LT |
1341 | } |
1342 | ||
1343 | /* As per nm */ | |
1344 | static char elf_type(const Elf_Sym *sym, | |
1345 | Elf_Shdr *sechdrs, | |
1346 | const char *secstrings, | |
1347 | struct module *mod) | |
1348 | { | |
1349 | if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { | |
1350 | if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT) | |
1351 | return 'v'; | |
1352 | else | |
1353 | return 'w'; | |
1354 | } | |
1355 | if (sym->st_shndx == SHN_UNDEF) | |
1356 | return 'U'; | |
1357 | if (sym->st_shndx == SHN_ABS) | |
1358 | return 'a'; | |
1359 | if (sym->st_shndx >= SHN_LORESERVE) | |
1360 | return '?'; | |
1361 | if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR) | |
1362 | return 't'; | |
1363 | if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC | |
1364 | && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) { | |
1365 | if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE)) | |
1366 | return 'r'; | |
1367 | else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
1368 | return 'g'; | |
1369 | else | |
1370 | return 'd'; | |
1371 | } | |
1372 | if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { | |
1373 | if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL) | |
1374 | return 's'; | |
1375 | else | |
1376 | return 'b'; | |
1377 | } | |
1378 | if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name, | |
1379 | ".debug", strlen(".debug")) == 0) | |
1380 | return 'n'; | |
1381 | return '?'; | |
1382 | } | |
1383 | ||
1384 | static void add_kallsyms(struct module *mod, | |
1385 | Elf_Shdr *sechdrs, | |
1386 | unsigned int symindex, | |
1387 | unsigned int strindex, | |
1388 | const char *secstrings) | |
1389 | { | |
1390 | unsigned int i; | |
1391 | ||
1392 | mod->symtab = (void *)sechdrs[symindex].sh_addr; | |
1393 | mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym); | |
1394 | mod->strtab = (void *)sechdrs[strindex].sh_addr; | |
1395 | ||
1396 | /* Set types up while we still have access to sections. */ | |
1397 | for (i = 0; i < mod->num_symtab; i++) | |
1398 | mod->symtab[i].st_info | |
1399 | = elf_type(&mod->symtab[i], sechdrs, secstrings, mod); | |
1400 | } | |
1401 | #else | |
1402 | static inline void add_kallsyms(struct module *mod, | |
1403 | Elf_Shdr *sechdrs, | |
1404 | unsigned int symindex, | |
1405 | unsigned int strindex, | |
1406 | const char *secstrings) | |
1407 | { | |
1408 | } | |
1409 | #endif /* CONFIG_KALLSYMS */ | |
1410 | ||
1411 | /* Allocate and load the module: note that size of section 0 is always | |
1412 | zero, and we rely on this for optional sections. */ | |
1413 | static struct module *load_module(void __user *umod, | |
1414 | unsigned long len, | |
1415 | const char __user *uargs) | |
1416 | { | |
1417 | Elf_Ehdr *hdr; | |
1418 | Elf_Shdr *sechdrs; | |
1419 | char *secstrings, *args, *modmagic, *strtab = NULL; | |
1420 | unsigned int i, symindex = 0, strindex = 0, setupindex, exindex, | |
1421 | exportindex, modindex, obsparmindex, infoindex, gplindex, | |
9f28bb7e GKH |
1422 | crcindex, gplcrcindex, versindex, pcpuindex, gplfutureindex, |
1423 | gplfuturecrcindex; | |
1da177e4 LT |
1424 | struct module *mod; |
1425 | long err = 0; | |
1426 | void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */ | |
1427 | struct exception_table_entry *extable; | |
378bac82 | 1428 | mm_segment_t old_fs; |
1da177e4 LT |
1429 | |
1430 | DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n", | |
1431 | umod, len, uargs); | |
1432 | if (len < sizeof(*hdr)) | |
1433 | return ERR_PTR(-ENOEXEC); | |
1434 | ||
1435 | /* Suck in entire file: we'll want most of it. */ | |
1436 | /* vmalloc barfs on "unusual" numbers. Check here */ | |
1437 | if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL) | |
1438 | return ERR_PTR(-ENOMEM); | |
1439 | if (copy_from_user(hdr, umod, len) != 0) { | |
1440 | err = -EFAULT; | |
1441 | goto free_hdr; | |
1442 | } | |
1443 | ||
1444 | /* Sanity checks against insmoding binaries or wrong arch, | |
1445 | weird elf version */ | |
1446 | if (memcmp(hdr->e_ident, ELFMAG, 4) != 0 | |
1447 | || hdr->e_type != ET_REL | |
1448 | || !elf_check_arch(hdr) | |
1449 | || hdr->e_shentsize != sizeof(*sechdrs)) { | |
1450 | err = -ENOEXEC; | |
1451 | goto free_hdr; | |
1452 | } | |
1453 | ||
1454 | if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) | |
1455 | goto truncated; | |
1456 | ||
1457 | /* Convenience variables */ | |
1458 | sechdrs = (void *)hdr + hdr->e_shoff; | |
1459 | secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; | |
1460 | sechdrs[0].sh_addr = 0; | |
1461 | ||
1462 | for (i = 1; i < hdr->e_shnum; i++) { | |
1463 | if (sechdrs[i].sh_type != SHT_NOBITS | |
1464 | && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) | |
1465 | goto truncated; | |
1466 | ||
1467 | /* Mark all sections sh_addr with their address in the | |
1468 | temporary image. */ | |
1469 | sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset; | |
1470 | ||
1471 | /* Internal symbols and strings. */ | |
1472 | if (sechdrs[i].sh_type == SHT_SYMTAB) { | |
1473 | symindex = i; | |
1474 | strindex = sechdrs[i].sh_link; | |
1475 | strtab = (char *)hdr + sechdrs[strindex].sh_offset; | |
1476 | } | |
1477 | #ifndef CONFIG_MODULE_UNLOAD | |
1478 | /* Don't load .exit sections */ | |
1479 | if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0) | |
1480 | sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
1481 | #endif | |
1482 | } | |
1483 | ||
1484 | modindex = find_sec(hdr, sechdrs, secstrings, | |
1485 | ".gnu.linkonce.this_module"); | |
1486 | if (!modindex) { | |
1487 | printk(KERN_WARNING "No module found in object\n"); | |
1488 | err = -ENOEXEC; | |
1489 | goto free_hdr; | |
1490 | } | |
1491 | mod = (void *)sechdrs[modindex].sh_addr; | |
1492 | ||
1493 | if (symindex == 0) { | |
1494 | printk(KERN_WARNING "%s: module has no symbols (stripped?)\n", | |
1495 | mod->name); | |
1496 | err = -ENOEXEC; | |
1497 | goto free_hdr; | |
1498 | } | |
1499 | ||
1500 | /* Optional sections */ | |
1501 | exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab"); | |
1502 | gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl"); | |
9f28bb7e | 1503 | gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future"); |
1da177e4 LT |
1504 | crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab"); |
1505 | gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl"); | |
9f28bb7e | 1506 | gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future"); |
1da177e4 LT |
1507 | setupindex = find_sec(hdr, sechdrs, secstrings, "__param"); |
1508 | exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table"); | |
1509 | obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm"); | |
1510 | versindex = find_sec(hdr, sechdrs, secstrings, "__versions"); | |
1511 | infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo"); | |
1512 | pcpuindex = find_pcpusec(hdr, sechdrs, secstrings); | |
1513 | ||
1514 | /* Don't keep modinfo section */ | |
1515 | sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
1516 | #ifdef CONFIG_KALLSYMS | |
1517 | /* Keep symbol and string tables for decoding later. */ | |
1518 | sechdrs[symindex].sh_flags |= SHF_ALLOC; | |
1519 | sechdrs[strindex].sh_flags |= SHF_ALLOC; | |
1520 | #endif | |
1521 | ||
1522 | /* Check module struct version now, before we try to use module. */ | |
1523 | if (!check_modstruct_version(sechdrs, versindex, mod)) { | |
1524 | err = -ENOEXEC; | |
1525 | goto free_hdr; | |
1526 | } | |
1527 | ||
1528 | modmagic = get_modinfo(sechdrs, infoindex, "vermagic"); | |
1529 | /* This is allowed: modprobe --force will invalidate it. */ | |
1530 | if (!modmagic) { | |
9f158333 | 1531 | add_taint(TAINT_FORCED_MODULE); |
1da177e4 LT |
1532 | printk(KERN_WARNING "%s: no version magic, tainting kernel.\n", |
1533 | mod->name); | |
1534 | } else if (!same_magic(modmagic, vermagic)) { | |
1535 | printk(KERN_ERR "%s: version magic '%s' should be '%s'\n", | |
1536 | mod->name, modmagic, vermagic); | |
1537 | err = -ENOEXEC; | |
1538 | goto free_hdr; | |
1539 | } | |
1540 | ||
1541 | /* Now copy in args */ | |
24277dda DA |
1542 | args = strndup_user(uargs, ~0UL >> 1); |
1543 | if (IS_ERR(args)) { | |
1544 | err = PTR_ERR(args); | |
1da177e4 LT |
1545 | goto free_hdr; |
1546 | } | |
8e08b756 | 1547 | |
1da177e4 LT |
1548 | if (find_module(mod->name)) { |
1549 | err = -EEXIST; | |
1550 | goto free_mod; | |
1551 | } | |
1552 | ||
1553 | mod->state = MODULE_STATE_COMING; | |
1554 | ||
1555 | /* Allow arches to frob section contents and sizes. */ | |
1556 | err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod); | |
1557 | if (err < 0) | |
1558 | goto free_mod; | |
1559 | ||
1560 | if (pcpuindex) { | |
1561 | /* We have a special allocation for this section. */ | |
1562 | percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size, | |
842bbaaa RR |
1563 | sechdrs[pcpuindex].sh_addralign, |
1564 | mod->name); | |
1da177e4 LT |
1565 | if (!percpu) { |
1566 | err = -ENOMEM; | |
1567 | goto free_mod; | |
1568 | } | |
1569 | sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC; | |
1570 | mod->percpu = percpu; | |
1571 | } | |
1572 | ||
1573 | /* Determine total sizes, and put offsets in sh_entsize. For now | |
1574 | this is done generically; there doesn't appear to be any | |
1575 | special cases for the architectures. */ | |
1576 | layout_sections(mod, hdr, sechdrs, secstrings); | |
1577 | ||
1578 | /* Do the allocs. */ | |
1579 | ptr = module_alloc(mod->core_size); | |
1580 | if (!ptr) { | |
1581 | err = -ENOMEM; | |
1582 | goto free_percpu; | |
1583 | } | |
1584 | memset(ptr, 0, mod->core_size); | |
1585 | mod->module_core = ptr; | |
1586 | ||
1587 | ptr = module_alloc(mod->init_size); | |
1588 | if (!ptr && mod->init_size) { | |
1589 | err = -ENOMEM; | |
1590 | goto free_core; | |
1591 | } | |
1592 | memset(ptr, 0, mod->init_size); | |
1593 | mod->module_init = ptr; | |
1594 | ||
1595 | /* Transfer each section which specifies SHF_ALLOC */ | |
1596 | DEBUGP("final section addresses:\n"); | |
1597 | for (i = 0; i < hdr->e_shnum; i++) { | |
1598 | void *dest; | |
1599 | ||
1600 | if (!(sechdrs[i].sh_flags & SHF_ALLOC)) | |
1601 | continue; | |
1602 | ||
1603 | if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK) | |
1604 | dest = mod->module_init | |
1605 | + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK); | |
1606 | else | |
1607 | dest = mod->module_core + sechdrs[i].sh_entsize; | |
1608 | ||
1609 | if (sechdrs[i].sh_type != SHT_NOBITS) | |
1610 | memcpy(dest, (void *)sechdrs[i].sh_addr, | |
1611 | sechdrs[i].sh_size); | |
1612 | /* Update sh_addr to point to copy in image. */ | |
1613 | sechdrs[i].sh_addr = (unsigned long)dest; | |
1614 | DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name); | |
1615 | } | |
1616 | /* Module has been moved. */ | |
1617 | mod = (void *)sechdrs[modindex].sh_addr; | |
1618 | ||
1619 | /* Now we've moved module, initialize linked lists, etc. */ | |
1620 | module_unload_init(mod); | |
1621 | ||
1622 | /* Set up license info based on the info section */ | |
1623 | set_license(mod, get_modinfo(sechdrs, infoindex, "license")); | |
1624 | ||
9841d61d DJ |
1625 | if (strcmp(mod->name, "ndiswrapper") == 0) |
1626 | add_taint(TAINT_PROPRIETARY_MODULE); | |
1627 | if (strcmp(mod->name, "driverloader") == 0) | |
1628 | add_taint(TAINT_PROPRIETARY_MODULE); | |
1629 | ||
c988d2b2 MD |
1630 | /* Set up MODINFO_ATTR fields */ |
1631 | setup_modinfo(mod, sechdrs, infoindex); | |
c988d2b2 | 1632 | |
1da177e4 LT |
1633 | /* Fix up syms, so that st_value is a pointer to location. */ |
1634 | err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex, | |
1635 | mod); | |
1636 | if (err < 0) | |
1637 | goto cleanup; | |
1638 | ||
1639 | /* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */ | |
1640 | mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms); | |
1641 | mod->syms = (void *)sechdrs[exportindex].sh_addr; | |
1642 | if (crcindex) | |
1643 | mod->crcs = (void *)sechdrs[crcindex].sh_addr; | |
1644 | mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms); | |
1645 | mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr; | |
1646 | if (gplcrcindex) | |
1647 | mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr; | |
9f28bb7e GKH |
1648 | mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size / |
1649 | sizeof(*mod->gpl_future_syms); | |
1650 | mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr; | |
1651 | if (gplfuturecrcindex) | |
1652 | mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr; | |
1da177e4 LT |
1653 | |
1654 | #ifdef CONFIG_MODVERSIONS | |
1655 | if ((mod->num_syms && !crcindex) || | |
9f28bb7e GKH |
1656 | (mod->num_gpl_syms && !gplcrcindex) || |
1657 | (mod->num_gpl_future_syms && !gplfuturecrcindex)) { | |
1da177e4 LT |
1658 | printk(KERN_WARNING "%s: No versions for exported symbols." |
1659 | " Tainting kernel.\n", mod->name); | |
9f158333 | 1660 | add_taint(TAINT_FORCED_MODULE); |
1da177e4 LT |
1661 | } |
1662 | #endif | |
1663 | ||
1664 | /* Now do relocations. */ | |
1665 | for (i = 1; i < hdr->e_shnum; i++) { | |
1666 | const char *strtab = (char *)sechdrs[strindex].sh_addr; | |
1667 | unsigned int info = sechdrs[i].sh_info; | |
1668 | ||
1669 | /* Not a valid relocation section? */ | |
1670 | if (info >= hdr->e_shnum) | |
1671 | continue; | |
1672 | ||
1673 | /* Don't bother with non-allocated sections */ | |
1674 | if (!(sechdrs[info].sh_flags & SHF_ALLOC)) | |
1675 | continue; | |
1676 | ||
1677 | if (sechdrs[i].sh_type == SHT_REL) | |
1678 | err = apply_relocate(sechdrs, strtab, symindex, i,mod); | |
1679 | else if (sechdrs[i].sh_type == SHT_RELA) | |
1680 | err = apply_relocate_add(sechdrs, strtab, symindex, i, | |
1681 | mod); | |
1682 | if (err < 0) | |
1683 | goto cleanup; | |
1684 | } | |
1685 | ||
eea8b54d AN |
1686 | /* Find duplicate symbols */ |
1687 | err = verify_export_symbols(mod); | |
1688 | ||
1689 | if (err < 0) | |
1690 | goto cleanup; | |
1691 | ||
1da177e4 LT |
1692 | /* Set up and sort exception table */ |
1693 | mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable); | |
1694 | mod->extable = extable = (void *)sechdrs[exindex].sh_addr; | |
1695 | sort_extable(extable, extable + mod->num_exentries); | |
1696 | ||
1697 | /* Finally, copy percpu area over. */ | |
1698 | percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr, | |
1699 | sechdrs[pcpuindex].sh_size); | |
1700 | ||
1701 | add_kallsyms(mod, sechdrs, symindex, strindex, secstrings); | |
1702 | ||
1703 | err = module_finalize(hdr, sechdrs, mod); | |
1704 | if (err < 0) | |
1705 | goto cleanup; | |
1706 | ||
378bac82 TK |
1707 | /* flush the icache in correct context */ |
1708 | old_fs = get_fs(); | |
1709 | set_fs(KERNEL_DS); | |
1710 | ||
1711 | /* | |
1712 | * Flush the instruction cache, since we've played with text. | |
1713 | * Do it before processing of module parameters, so the module | |
1714 | * can provide parameter accessor functions of its own. | |
1715 | */ | |
1716 | if (mod->module_init) | |
1717 | flush_icache_range((unsigned long)mod->module_init, | |
1718 | (unsigned long)mod->module_init | |
1719 | + mod->init_size); | |
1720 | flush_icache_range((unsigned long)mod->module_core, | |
1721 | (unsigned long)mod->module_core + mod->core_size); | |
1722 | ||
1723 | set_fs(old_fs); | |
1724 | ||
1da177e4 | 1725 | mod->args = args; |
8d3b33f6 RR |
1726 | if (obsparmindex) |
1727 | printk(KERN_WARNING "%s: Ignoring obsolete parameters\n", | |
1728 | mod->name); | |
1729 | ||
1730 | /* Size of section 0 is 0, so this works well if no params */ | |
1731 | err = parse_args(mod->name, mod->args, | |
1732 | (struct kernel_param *) | |
1733 | sechdrs[setupindex].sh_addr, | |
1734 | sechdrs[setupindex].sh_size | |
1735 | / sizeof(struct kernel_param), | |
1736 | NULL); | |
1da177e4 LT |
1737 | if (err < 0) |
1738 | goto arch_cleanup; | |
1739 | ||
1740 | err = mod_sysfs_setup(mod, | |
1741 | (struct kernel_param *) | |
1742 | sechdrs[setupindex].sh_addr, | |
1743 | sechdrs[setupindex].sh_size | |
1744 | / sizeof(struct kernel_param)); | |
1745 | if (err < 0) | |
1746 | goto arch_cleanup; | |
1747 | add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs); | |
1748 | ||
1749 | /* Get rid of temporary copy */ | |
1750 | vfree(hdr); | |
1751 | ||
1752 | /* Done! */ | |
1753 | return mod; | |
1754 | ||
1755 | arch_cleanup: | |
1756 | module_arch_cleanup(mod); | |
1757 | cleanup: | |
1758 | module_unload_free(mod); | |
1759 | module_free(mod, mod->module_init); | |
1760 | free_core: | |
1761 | module_free(mod, mod->module_core); | |
1762 | free_percpu: | |
1763 | if (percpu) | |
1764 | percpu_modfree(percpu); | |
1765 | free_mod: | |
1766 | kfree(args); | |
1767 | free_hdr: | |
1768 | vfree(hdr); | |
6fe2e70b | 1769 | return ERR_PTR(err); |
1da177e4 LT |
1770 | |
1771 | truncated: | |
1772 | printk(KERN_ERR "Module len %lu truncated\n", len); | |
1773 | err = -ENOEXEC; | |
1774 | goto free_hdr; | |
1775 | } | |
1776 | ||
1777 | /* | |
1778 | * link the module with the whole machine is stopped with interrupts off | |
1779 | * - this defends against kallsyms not taking locks | |
1780 | */ | |
1781 | static int __link_module(void *_mod) | |
1782 | { | |
1783 | struct module *mod = _mod; | |
1784 | list_add(&mod->list, &modules); | |
1785 | return 0; | |
1786 | } | |
1787 | ||
1788 | /* This is where the real work happens */ | |
1789 | asmlinkage long | |
1790 | sys_init_module(void __user *umod, | |
1791 | unsigned long len, | |
1792 | const char __user *uargs) | |
1793 | { | |
1794 | struct module *mod; | |
1795 | int ret = 0; | |
1796 | ||
1797 | /* Must have permission */ | |
1798 | if (!capable(CAP_SYS_MODULE)) | |
1799 | return -EPERM; | |
1800 | ||
1801 | /* Only one module load at a time, please */ | |
6389a385 | 1802 | if (mutex_lock_interruptible(&module_mutex) != 0) |
1da177e4 LT |
1803 | return -EINTR; |
1804 | ||
1805 | /* Do all the hard work */ | |
1806 | mod = load_module(umod, len, uargs); | |
1807 | if (IS_ERR(mod)) { | |
6389a385 | 1808 | mutex_unlock(&module_mutex); |
1da177e4 LT |
1809 | return PTR_ERR(mod); |
1810 | } | |
1811 | ||
1da177e4 LT |
1812 | /* Now sew it into the lists. They won't access us, since |
1813 | strong_try_module_get() will fail. */ | |
1814 | stop_machine_run(__link_module, mod, NR_CPUS); | |
1815 | ||
1816 | /* Drop lock so they can recurse */ | |
6389a385 | 1817 | mutex_unlock(&module_mutex); |
1da177e4 | 1818 | |
97d1f15b | 1819 | mutex_lock(¬ify_mutex); |
1da177e4 | 1820 | notifier_call_chain(&module_notify_list, MODULE_STATE_COMING, mod); |
97d1f15b | 1821 | mutex_unlock(¬ify_mutex); |
1da177e4 LT |
1822 | |
1823 | /* Start the module */ | |
1824 | if (mod->init != NULL) | |
1825 | ret = mod->init(); | |
1826 | if (ret < 0) { | |
1827 | /* Init routine failed: abort. Try to protect us from | |
1828 | buggy refcounters. */ | |
1829 | mod->state = MODULE_STATE_GOING; | |
fbd568a3 | 1830 | synchronize_sched(); |
1da177e4 LT |
1831 | if (mod->unsafe) |
1832 | printk(KERN_ERR "%s: module is now stuck!\n", | |
1833 | mod->name); | |
1834 | else { | |
1835 | module_put(mod); | |
6389a385 | 1836 | mutex_lock(&module_mutex); |
1da177e4 | 1837 | free_module(mod); |
6389a385 | 1838 | mutex_unlock(&module_mutex); |
1da177e4 LT |
1839 | } |
1840 | return ret; | |
1841 | } | |
1842 | ||
1843 | /* Now it's a first class citizen! */ | |
6389a385 | 1844 | mutex_lock(&module_mutex); |
1da177e4 LT |
1845 | mod->state = MODULE_STATE_LIVE; |
1846 | /* Drop initial reference. */ | |
1847 | module_put(mod); | |
1848 | module_free(mod, mod->module_init); | |
1849 | mod->module_init = NULL; | |
1850 | mod->init_size = 0; | |
1851 | mod->init_text_size = 0; | |
6389a385 | 1852 | mutex_unlock(&module_mutex); |
1da177e4 LT |
1853 | |
1854 | return 0; | |
1855 | } | |
1856 | ||
1857 | static inline int within(unsigned long addr, void *start, unsigned long size) | |
1858 | { | |
1859 | return ((void *)addr >= start && (void *)addr < start + size); | |
1860 | } | |
1861 | ||
1862 | #ifdef CONFIG_KALLSYMS | |
1863 | /* | |
1864 | * This ignores the intensely annoying "mapping symbols" found | |
1865 | * in ARM ELF files: $a, $t and $d. | |
1866 | */ | |
1867 | static inline int is_arm_mapping_symbol(const char *str) | |
1868 | { | |
1869 | return str[0] == '$' && strchr("atd", str[1]) | |
1870 | && (str[2] == '\0' || str[2] == '.'); | |
1871 | } | |
1872 | ||
1873 | static const char *get_ksymbol(struct module *mod, | |
1874 | unsigned long addr, | |
1875 | unsigned long *size, | |
1876 | unsigned long *offset) | |
1877 | { | |
1878 | unsigned int i, best = 0; | |
1879 | unsigned long nextval; | |
1880 | ||
1881 | /* At worse, next value is at end of module */ | |
1882 | if (within(addr, mod->module_init, mod->init_size)) | |
1883 | nextval = (unsigned long)mod->module_init+mod->init_text_size; | |
1884 | else | |
1885 | nextval = (unsigned long)mod->module_core+mod->core_text_size; | |
1886 | ||
1887 | /* Scan for closest preceeding symbol, and next symbol. (ELF | |
1888 | starts real symbols at 1). */ | |
1889 | for (i = 1; i < mod->num_symtab; i++) { | |
1890 | if (mod->symtab[i].st_shndx == SHN_UNDEF) | |
1891 | continue; | |
1892 | ||
1893 | /* We ignore unnamed symbols: they're uninformative | |
1894 | * and inserted at a whim. */ | |
1895 | if (mod->symtab[i].st_value <= addr | |
1896 | && mod->symtab[i].st_value > mod->symtab[best].st_value | |
1897 | && *(mod->strtab + mod->symtab[i].st_name) != '\0' | |
1898 | && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name)) | |
1899 | best = i; | |
1900 | if (mod->symtab[i].st_value > addr | |
1901 | && mod->symtab[i].st_value < nextval | |
1902 | && *(mod->strtab + mod->symtab[i].st_name) != '\0' | |
1903 | && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name)) | |
1904 | nextval = mod->symtab[i].st_value; | |
1905 | } | |
1906 | ||
1907 | if (!best) | |
1908 | return NULL; | |
1909 | ||
1910 | *size = nextval - mod->symtab[best].st_value; | |
1911 | *offset = addr - mod->symtab[best].st_value; | |
1912 | return mod->strtab + mod->symtab[best].st_name; | |
1913 | } | |
1914 | ||
1915 | /* For kallsyms to ask for address resolution. NULL means not found. | |
1916 | We don't lock, as this is used for oops resolution and races are a | |
1917 | lesser concern. */ | |
1918 | const char *module_address_lookup(unsigned long addr, | |
1919 | unsigned long *size, | |
1920 | unsigned long *offset, | |
1921 | char **modname) | |
1922 | { | |
1923 | struct module *mod; | |
1924 | ||
1925 | list_for_each_entry(mod, &modules, list) { | |
1926 | if (within(addr, mod->module_init, mod->init_size) | |
1927 | || within(addr, mod->module_core, mod->core_size)) { | |
1928 | *modname = mod->name; | |
1929 | return get_ksymbol(mod, addr, size, offset); | |
1930 | } | |
1931 | } | |
1932 | return NULL; | |
1933 | } | |
1934 | ||
1935 | struct module *module_get_kallsym(unsigned int symnum, | |
1936 | unsigned long *value, | |
1937 | char *type, | |
1938 | char namebuf[128]) | |
1939 | { | |
1940 | struct module *mod; | |
1941 | ||
6389a385 | 1942 | mutex_lock(&module_mutex); |
1da177e4 LT |
1943 | list_for_each_entry(mod, &modules, list) { |
1944 | if (symnum < mod->num_symtab) { | |
1945 | *value = mod->symtab[symnum].st_value; | |
1946 | *type = mod->symtab[symnum].st_info; | |
1947 | strncpy(namebuf, | |
1948 | mod->strtab + mod->symtab[symnum].st_name, | |
1949 | 127); | |
6389a385 | 1950 | mutex_unlock(&module_mutex); |
1da177e4 LT |
1951 | return mod; |
1952 | } | |
1953 | symnum -= mod->num_symtab; | |
1954 | } | |
6389a385 | 1955 | mutex_unlock(&module_mutex); |
1da177e4 LT |
1956 | return NULL; |
1957 | } | |
1958 | ||
1959 | static unsigned long mod_find_symname(struct module *mod, const char *name) | |
1960 | { | |
1961 | unsigned int i; | |
1962 | ||
1963 | for (i = 0; i < mod->num_symtab; i++) | |
54e8ce46 KO |
1964 | if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 && |
1965 | mod->symtab[i].st_info != 'U') | |
1da177e4 LT |
1966 | return mod->symtab[i].st_value; |
1967 | return 0; | |
1968 | } | |
1969 | ||
1970 | /* Look for this name: can be of form module:name. */ | |
1971 | unsigned long module_kallsyms_lookup_name(const char *name) | |
1972 | { | |
1973 | struct module *mod; | |
1974 | char *colon; | |
1975 | unsigned long ret = 0; | |
1976 | ||
1977 | /* Don't lock: we're in enough trouble already. */ | |
1978 | if ((colon = strchr(name, ':')) != NULL) { | |
1979 | *colon = '\0'; | |
1980 | if ((mod = find_module(name)) != NULL) | |
1981 | ret = mod_find_symname(mod, colon+1); | |
1982 | *colon = ':'; | |
1983 | } else { | |
1984 | list_for_each_entry(mod, &modules, list) | |
1985 | if ((ret = mod_find_symname(mod, name)) != 0) | |
1986 | break; | |
1987 | } | |
1988 | return ret; | |
1989 | } | |
1990 | #endif /* CONFIG_KALLSYMS */ | |
1991 | ||
1992 | /* Called by the /proc file system to return a list of modules. */ | |
1993 | static void *m_start(struct seq_file *m, loff_t *pos) | |
1994 | { | |
1995 | struct list_head *i; | |
1996 | loff_t n = 0; | |
1997 | ||
6389a385 | 1998 | mutex_lock(&module_mutex); |
1da177e4 LT |
1999 | list_for_each(i, &modules) { |
2000 | if (n++ == *pos) | |
2001 | break; | |
2002 | } | |
2003 | if (i == &modules) | |
2004 | return NULL; | |
2005 | return i; | |
2006 | } | |
2007 | ||
2008 | static void *m_next(struct seq_file *m, void *p, loff_t *pos) | |
2009 | { | |
2010 | struct list_head *i = p; | |
2011 | (*pos)++; | |
2012 | if (i->next == &modules) | |
2013 | return NULL; | |
2014 | return i->next; | |
2015 | } | |
2016 | ||
2017 | static void m_stop(struct seq_file *m, void *p) | |
2018 | { | |
6389a385 | 2019 | mutex_unlock(&module_mutex); |
1da177e4 LT |
2020 | } |
2021 | ||
2022 | static int m_show(struct seq_file *m, void *p) | |
2023 | { | |
2024 | struct module *mod = list_entry(p, struct module, list); | |
2025 | seq_printf(m, "%s %lu", | |
2026 | mod->name, mod->init_size + mod->core_size); | |
2027 | print_unload_info(m, mod); | |
2028 | ||
2029 | /* Informative for users. */ | |
2030 | seq_printf(m, " %s", | |
2031 | mod->state == MODULE_STATE_GOING ? "Unloading": | |
2032 | mod->state == MODULE_STATE_COMING ? "Loading": | |
2033 | "Live"); | |
2034 | /* Used by oprofile and other similar tools. */ | |
2035 | seq_printf(m, " 0x%p", mod->module_core); | |
2036 | ||
2037 | seq_printf(m, "\n"); | |
2038 | return 0; | |
2039 | } | |
2040 | ||
2041 | /* Format: modulename size refcount deps address | |
2042 | ||
2043 | Where refcount is a number or -, and deps is a comma-separated list | |
2044 | of depends or -. | |
2045 | */ | |
2046 | struct seq_operations modules_op = { | |
2047 | .start = m_start, | |
2048 | .next = m_next, | |
2049 | .stop = m_stop, | |
2050 | .show = m_show | |
2051 | }; | |
2052 | ||
2053 | /* Given an address, look for it in the module exception tables. */ | |
2054 | const struct exception_table_entry *search_module_extables(unsigned long addr) | |
2055 | { | |
2056 | unsigned long flags; | |
2057 | const struct exception_table_entry *e = NULL; | |
2058 | struct module *mod; | |
2059 | ||
2060 | spin_lock_irqsave(&modlist_lock, flags); | |
2061 | list_for_each_entry(mod, &modules, list) { | |
2062 | if (mod->num_exentries == 0) | |
2063 | continue; | |
2064 | ||
2065 | e = search_extable(mod->extable, | |
2066 | mod->extable + mod->num_exentries - 1, | |
2067 | addr); | |
2068 | if (e) | |
2069 | break; | |
2070 | } | |
2071 | spin_unlock_irqrestore(&modlist_lock, flags); | |
2072 | ||
2073 | /* Now, if we found one, we are running inside it now, hence | |
2074 | we cannot unload the module, hence no refcnt needed. */ | |
2075 | return e; | |
2076 | } | |
2077 | ||
2078 | /* Is this a valid kernel address? We don't grab the lock: we are oopsing. */ | |
2079 | struct module *__module_text_address(unsigned long addr) | |
2080 | { | |
2081 | struct module *mod; | |
2082 | ||
2083 | list_for_each_entry(mod, &modules, list) | |
2084 | if (within(addr, mod->module_init, mod->init_text_size) | |
2085 | || within(addr, mod->module_core, mod->core_text_size)) | |
2086 | return mod; | |
2087 | return NULL; | |
2088 | } | |
2089 | ||
2090 | struct module *module_text_address(unsigned long addr) | |
2091 | { | |
2092 | struct module *mod; | |
2093 | unsigned long flags; | |
2094 | ||
2095 | spin_lock_irqsave(&modlist_lock, flags); | |
2096 | mod = __module_text_address(addr); | |
2097 | spin_unlock_irqrestore(&modlist_lock, flags); | |
2098 | ||
2099 | return mod; | |
2100 | } | |
2101 | ||
2102 | /* Don't grab lock, we're oopsing. */ | |
2103 | void print_modules(void) | |
2104 | { | |
2105 | struct module *mod; | |
2106 | ||
2107 | printk("Modules linked in:"); | |
2108 | list_for_each_entry(mod, &modules, list) | |
2109 | printk(" %s", mod->name); | |
2110 | printk("\n"); | |
2111 | } | |
2112 | ||
2113 | void module_add_driver(struct module *mod, struct device_driver *drv) | |
2114 | { | |
2115 | if (!mod || !drv) | |
2116 | return; | |
2117 | ||
2118 | /* Don't check return code; this call is idempotent */ | |
2119 | sysfs_create_link(&drv->kobj, &mod->mkobj.kobj, "module"); | |
2120 | } | |
2121 | EXPORT_SYMBOL(module_add_driver); | |
2122 | ||
2123 | void module_remove_driver(struct device_driver *drv) | |
2124 | { | |
2125 | if (!drv) | |
2126 | return; | |
2127 | sysfs_remove_link(&drv->kobj, "module"); | |
2128 | } | |
2129 | EXPORT_SYMBOL(module_remove_driver); | |
2130 | ||
2131 | #ifdef CONFIG_MODVERSIONS | |
2132 | /* Generate the signature for struct module here, too, for modversions. */ | |
2133 | void struct_module(struct module *mod) { return; } | |
2134 | EXPORT_SYMBOL(struct_module); | |
2135 | #endif |