module.c 96 KB
Newer Older
1
/*
Linus Torvalds's avatar
Linus Torvalds committed
2
   Copyright (C) 2002 Richard Henderson
3
   Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
Linus Torvalds's avatar
Linus Torvalds committed
4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
19
#include <linux/export.h>
Linus Torvalds's avatar
Linus Torvalds committed
20
#include <linux/moduleloader.h>
21
#include <linux/ftrace_event.h>
Linus Torvalds's avatar
Linus Torvalds committed
22
#include <linux/init.h>
23
#include <linux/kallsyms.h>
24
#include <linux/file.h>
25
#include <linux/fs.h>
Roland McGrath's avatar
Roland McGrath committed
26
#include <linux/sysfs.h>
27
#include <linux/kernel.h>
Linus Torvalds's avatar
Linus Torvalds committed
28 29 30
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/elf.h>
31
#include <linux/proc_fs.h>
32
#include <linux/security.h>
Linus Torvalds's avatar
Linus Torvalds committed
33 34 35 36
#include <linux/seq_file.h>
#include <linux/syscalls.h>
#include <linux/fcntl.h>
#include <linux/rcupdate.h>
37
#include <linux/capability.h>
Linus Torvalds's avatar
Linus Torvalds committed
38 39 40 41 42 43
#include <linux/cpu.h>
#include <linux/moduleparam.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/vermagic.h>
#include <linux/notifier.h>
Al Viro's avatar
Al Viro committed
44
#include <linux/sched.h>
Linus Torvalds's avatar
Linus Torvalds committed
45 46
#include <linux/stop_machine.h>
#include <linux/device.h>
47
#include <linux/string.h>
48
#include <linux/mutex.h>
49
#include <linux/rculist.h>
Linus Torvalds's avatar
Linus Torvalds committed
50 51
#include <asm/uaccess.h>
#include <asm/cacheflush.h>
52
#include <asm/mmu_context.h>
53
#include <linux/license.h>
54
#include <asm/sections.h>
55
#include <linux/tracepoint.h>
56
#include <linux/ftrace.h>
57
#include <linux/async.h>
58
#include <linux/percpu.h>
59
#include <linux/kmemleak.h>
60
#include <linux/jump_label.h>
61
#include <linux/pfn.h>
62
#include <linux/bsearch.h>
David Howells's avatar
David Howells committed
63
#include <linux/fips.h>
64
#include <uapi/linux/module.h>
65
#include "module-internal.h"
Linus Torvalds's avatar
Linus Torvalds committed
66

67 68 69
#define CREATE_TRACE_POINTS
#include <trace/events/module.h>

Linus Torvalds's avatar
Linus Torvalds committed
70 71 72 73
#ifndef ARCH_SHF_SMALL
#define ARCH_SHF_SMALL 0
#endif

74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93
/*
 * Modules' sections will be aligned on page boundaries
 * to ensure complete separation of code and data, but
 * only when CONFIG_DEBUG_SET_MODULE_RONX=y
 */
#ifdef CONFIG_DEBUG_SET_MODULE_RONX
# define debug_align(X) ALIGN(X, PAGE_SIZE)
#else
# define debug_align(X) (X)
#endif

/*
 * Given BASE and SIZE this macro calculates the number of pages the
 * memory regions occupies
 */
#define MOD_NUMBER_OF_PAGES(BASE, SIZE) (((SIZE) > 0) ?		\
		(PFN_DOWN((unsigned long)(BASE) + (SIZE) - 1) -	\
			 PFN_DOWN((unsigned long)BASE) + 1)	\
		: (0UL))

Linus Torvalds's avatar
Linus Torvalds committed
94 95 96
/* If this is set, the section belongs in the init part of the module */
#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))

97 98 99 100 101
/*
 * Mutex protects:
 * 1) List of modules (also safely readable with preempt_disable),
 * 2) module_use links,
 * 3) module_addr_min/module_addr_max.
102
 * (delete uses stop_machine/add uses RCU list operations). */
103 104
DEFINE_MUTEX(module_mutex);
EXPORT_SYMBOL_GPL(module_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
105
static LIST_HEAD(modules);
106 107 108 109
#ifdef CONFIG_KGDB_KDB
struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
#endif /* CONFIG_KGDB_KDB */

110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146
#ifdef CONFIG_MODULE_SIG
#ifdef CONFIG_MODULE_SIG_FORCE
static bool sig_enforce = true;
#else
static bool sig_enforce = false;

static int param_set_bool_enable_only(const char *val,
				      const struct kernel_param *kp)
{
	int err;
	bool test;
	struct kernel_param dummy_kp = *kp;

	dummy_kp.arg = &test;

	err = param_set_bool(val, &dummy_kp);
	if (err)
		return err;

	/* Don't let them unset it once it's set! */
	if (!test && sig_enforce)
		return -EROFS;

	if (test)
		sig_enforce = true;
	return 0;
}

static const struct kernel_param_ops param_ops_bool_enable_only = {
	.set = param_set_bool_enable_only,
	.get = param_get_bool,
};
#define param_check_bool_enable_only param_check_bool

module_param(sig_enforce, bool_enable_only, 0644);
#endif /* !CONFIG_MODULE_SIG_FORCE */
#endif /* CONFIG_MODULE_SIG */
Linus Torvalds's avatar
Linus Torvalds committed
147

148 149
/* Block module loading/unloading? */
int modules_disabled = 0;
150
core_param(nomodule, modules_disabled, bint, 0);
151

152 153 154
/* Waiting for a module to finish initializing? */
static DECLARE_WAIT_QUEUE_HEAD(module_wq);

155
static BLOCKING_NOTIFIER_HEAD(module_notify_list);
Linus Torvalds's avatar
Linus Torvalds committed
156

157 158
/* Bounds of module allocation, for speeding __module_address.
 * Protected by module_mutex. */
159 160
static unsigned long module_addr_min = -1UL, module_addr_max = 0;

Linus Torvalds's avatar
Linus Torvalds committed
161 162
int register_module_notifier(struct notifier_block * nb)
{
163
	return blocking_notifier_chain_register(&module_notify_list, nb);
Linus Torvalds's avatar
Linus Torvalds committed
164 165 166 167 168
}
EXPORT_SYMBOL(register_module_notifier);

int unregister_module_notifier(struct notifier_block * nb)
{
169
	return blocking_notifier_chain_unregister(&module_notify_list, nb);
Linus Torvalds's avatar
Linus Torvalds committed
170 171 172
}
EXPORT_SYMBOL(unregister_module_notifier);

173 174 175 176
struct load_info {
	Elf_Ehdr *hdr;
	unsigned long len;
	Elf_Shdr *sechdrs;
177
	char *secstrings, *strtab;
Rusty Russell's avatar
Rusty Russell committed
178
	unsigned long symoffs, stroffs;
179 180
	struct _ddebug *debug;
	unsigned int num_debug;
181
	bool sig_ok;
182 183 184 185 186
	struct {
		unsigned int sym, str, mod, vers, info, pcpu;
	} index;
};

187 188
/* We require a truly strong try_module_get(): 0 means failure due to
   ongoing or failed initialization etc. */
Linus Torvalds's avatar
Linus Torvalds committed
189 190
static inline int strong_try_module_get(struct module *mod)
{
191
	BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
Linus Torvalds's avatar
Linus Torvalds committed
192
	if (mod && mod->state == MODULE_STATE_COMING)
193 194
		return -EBUSY;
	if (try_module_get(mod))
Linus Torvalds's avatar
Linus Torvalds committed
195
		return 0;
196 197
	else
		return -ENOENT;
Linus Torvalds's avatar
Linus Torvalds committed
198 199
}

200 201 202
static inline void add_taint_module(struct module *mod, unsigned flag)
{
	add_taint(flag);
Andi Kleen's avatar
Andi Kleen committed
203
	mod->taints |= (1U << flag);
204 205
}

206 207 208
/*
 * A thread that wants to hold a reference to a module only while it
 * is running can call this to safely exit.  nfsd and lockd use this.
Linus Torvalds's avatar
Linus Torvalds committed
209 210 211 212 213 214 215
 */
void __module_put_and_exit(struct module *mod, long code)
{
	module_put(mod);
	do_exit(code);
}
EXPORT_SYMBOL(__module_put_and_exit);
216

Linus Torvalds's avatar
Linus Torvalds committed
217
/* Find a module section: 0 means not found. */
218
static unsigned int find_sec(const struct load_info *info, const char *name)
Linus Torvalds's avatar
Linus Torvalds committed
219 220 221
{
	unsigned int i;

222 223
	for (i = 1; i < info->hdr->e_shnum; i++) {
		Elf_Shdr *shdr = &info->sechdrs[i];
Linus Torvalds's avatar
Linus Torvalds committed
224
		/* Alloc bit cleared means "ignore it." */
225 226
		if ((shdr->sh_flags & SHF_ALLOC)
		    && strcmp(info->secstrings + shdr->sh_name, name) == 0)
Linus Torvalds's avatar
Linus Torvalds committed
227
			return i;
228
	}
Linus Torvalds's avatar
Linus Torvalds committed
229 230 231
	return 0;
}

232
/* Find a module section, or NULL. */
233
static void *section_addr(const struct load_info *info, const char *name)
234 235
{
	/* Section 0 has sh_addr 0. */
236
	return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
237 238 239
}

/* Find a module section, or NULL.  Fill in number of "objects" in section. */
240
static void *section_objs(const struct load_info *info,
241 242 243 244
			  const char *name,
			  size_t object_size,
			  unsigned int *num)
{
245
	unsigned int sec = find_sec(info, name);
246 247

	/* Section 0 has sh_addr 0 and sh_size 0. */
248 249
	*num = info->sechdrs[sec].sh_size / object_size;
	return (void *)info->sechdrs[sec].sh_addr;
250 251
}

Linus Torvalds's avatar
Linus Torvalds committed
252 253 254 255 256
/* Provided by the linker */
extern const struct kernel_symbol __start___ksymtab[];
extern const struct kernel_symbol __stop___ksymtab[];
extern const struct kernel_symbol __start___ksymtab_gpl[];
extern const struct kernel_symbol __stop___ksymtab_gpl[];
257 258
extern const struct kernel_symbol __start___ksymtab_gpl_future[];
extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
Linus Torvalds's avatar
Linus Torvalds committed
259 260
extern const unsigned long __start___kcrctab[];
extern const unsigned long __start___kcrctab_gpl[];
261
extern const unsigned long __start___kcrctab_gpl_future[];
262 263 264 265 266
#ifdef CONFIG_UNUSED_SYMBOLS
extern const struct kernel_symbol __start___ksymtab_unused[];
extern const struct kernel_symbol __stop___ksymtab_unused[];
extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
267 268
extern const unsigned long __start___kcrctab_unused[];
extern const unsigned long __start___kcrctab_unused_gpl[];
269
#endif
Linus Torvalds's avatar
Linus Torvalds committed
270 271 272 273

#ifndef CONFIG_MODVERSIONS
#define symversion(base, idx) NULL
#else
274
#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
Linus Torvalds's avatar
Linus Torvalds committed
275 276
#endif

277 278 279 280 281
static bool each_symbol_in_section(const struct symsearch *arr,
				   unsigned int arrsize,
				   struct module *owner,
				   bool (*fn)(const struct symsearch *syms,
					      struct module *owner,
282
					      void *data),
283
				   void *data)
284
{
285
	unsigned int j;
286

287
	for (j = 0; j < arrsize; j++) {
288 289
		if (fn(&arr[j], owner, data))
			return true;
290
	}
291 292

	return false;
293 294
}

295
/* Returns true as soon as fn returns true, otherwise false. */
296 297 298 299
bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
				    struct module *owner,
				    void *data),
			 void *data)
300 301
{
	struct module *mod;
302
	static const struct symsearch arr[] = {
303
		{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
304
		  NOT_GPL_ONLY, false },
305
		{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
306 307
		  __start___kcrctab_gpl,
		  GPL_ONLY, false },
308
		{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
309 310
		  __start___kcrctab_gpl_future,
		  WILL_BE_GPL_ONLY, false },
311
#ifdef CONFIG_UNUSED_SYMBOLS
312
		{ __start___ksymtab_unused, __stop___ksymtab_unused,
313 314
		  __start___kcrctab_unused,
		  NOT_GPL_ONLY, true },
315
		{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
316 317
		  __start___kcrctab_unused_gpl,
		  GPL_ONLY, true },
318
#endif
319
	};
320

321 322
	if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
		return true;
323

324
	list_for_each_entry_rcu(mod, &modules, list) {
325 326
		struct symsearch arr[] = {
			{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
327
			  NOT_GPL_ONLY, false },
328
			{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
329 330
			  mod->gpl_crcs,
			  GPL_ONLY, false },
331 332
			{ mod->gpl_future_syms,
			  mod->gpl_future_syms + mod->num_gpl_future_syms,
333 334
			  mod->gpl_future_crcs,
			  WILL_BE_GPL_ONLY, false },
335
#ifdef CONFIG_UNUSED_SYMBOLS
336 337
			{ mod->unused_syms,
			  mod->unused_syms + mod->num_unused_syms,
338 339
			  mod->unused_crcs,
			  NOT_GPL_ONLY, true },
340 341
			{ mod->unused_gpl_syms,
			  mod->unused_gpl_syms + mod->num_unused_gpl_syms,
342 343
			  mod->unused_gpl_crcs,
			  GPL_ONLY, true },
344
#endif
345 346
		};

347 348 349
		if (mod->state == MODULE_STATE_UNFORMED)
			continue;

350 351 352 353 354
		if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
			return true;
	}
	return false;
}
355
EXPORT_SYMBOL_GPL(each_symbol_section);
356 357 358 359 360 361 362 363 364 365

struct find_symbol_arg {
	/* Input */
	const char *name;
	bool gplok;
	bool warn;

	/* Output */
	struct module *owner;
	const unsigned long *crc;
366
	const struct kernel_symbol *sym;
367 368
};

369 370 371
static bool check_symbol(const struct symsearch *syms,
				 struct module *owner,
				 unsigned int symnum, void *data)
372 373 374 375 376 377 378 379 380 381
{
	struct find_symbol_arg *fsa = data;

	if (!fsa->gplok) {
		if (syms->licence == GPL_ONLY)
			return false;
		if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
			printk(KERN_WARNING "Symbol %s is being used "
			       "by a non-GPL module, which will not "
			       "be allowed in the future\n", fsa->name);
382
		}
Linus Torvalds's avatar
Linus Torvalds committed
383
	}
384

385
#ifdef CONFIG_UNUSED_SYMBOLS
386 387 388 389 390 391 392 393 394 395 396
	if (syms->unused && fsa->warn) {
		printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
		       "however this module is using it.\n", fsa->name);
		printk(KERN_WARNING
		       "This symbol will go away in the future.\n");
		printk(KERN_WARNING
		       "Please evalute if this is the right api to use and if "
		       "it really is, submit a report the linux kernel "
		       "mailinglist together with submitting your code for "
		       "inclusion.\n");
	}
397
#endif
398 399 400

	fsa->owner = owner;
	fsa->crc = symversion(syms->crcs, symnum);
401
	fsa->sym = &syms->start[symnum];
402 403 404
	return true;
}

405 406 407 408 409 410 411 412
static int cmp_name(const void *va, const void *vb)
{
	const char *a;
	const struct kernel_symbol *b;
	a = va; b = vb;
	return strcmp(a, b->name);
}

413 414 415 416 417
static bool find_symbol_in_section(const struct symsearch *syms,
				   struct module *owner,
				   void *data)
{
	struct find_symbol_arg *fsa = data;
418 419 420 421 422 423 424
	struct kernel_symbol *sym;

	sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
			sizeof(struct kernel_symbol), cmp_name);

	if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
		return true;
425 426 427 428

	return false;
}

429
/* Find a symbol and return it, along with, (optional) crc and
430
 * (optional) module which owns it.  Needs preempt disabled or module_mutex. */
431 432 433 434 435
const struct kernel_symbol *find_symbol(const char *name,
					struct module **owner,
					const unsigned long **crc,
					bool gplok,
					bool warn)
436 437 438 439 440 441 442
{
	struct find_symbol_arg fsa;

	fsa.name = name;
	fsa.gplok = gplok;
	fsa.warn = warn;

443
	if (each_symbol_section(find_symbol_in_section, &fsa)) {
444 445 446 447
		if (owner)
			*owner = fsa.owner;
		if (crc)
			*crc = fsa.crc;
448
		return fsa.sym;
449 450
	}

451
	pr_debug("Failed to find symbol %s\n", name);
452
	return NULL;
Linus Torvalds's avatar
Linus Torvalds committed
453
}
454
EXPORT_SYMBOL_GPL(find_symbol);
Linus Torvalds's avatar
Linus Torvalds committed
455 456

/* Search for module by name: must hold module_mutex. */
457 458
static struct module *find_module_all(const char *name,
				      bool even_unformed)
Linus Torvalds's avatar
Linus Torvalds committed
459 460 461 462
{
	struct module *mod;

	list_for_each_entry(mod, &modules, list) {
463 464
		if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
			continue;
Linus Torvalds's avatar
Linus Torvalds committed
465 466 467 468 469
		if (strcmp(mod->name, name) == 0)
			return mod;
	}
	return NULL;
}
470 471 472 473 474

struct module *find_module(const char *name)
{
	return find_module_all(name, false);
}
475
EXPORT_SYMBOL_GPL(find_module);
Linus Torvalds's avatar
Linus Torvalds committed
476 477

#ifdef CONFIG_SMP
478

479
static inline void __percpu *mod_percpu(struct module *mod)
480
{
481 482
	return mod->percpu;
}
483

484 485 486
static int percpu_modalloc(struct module *mod,
			   unsigned long size, unsigned long align)
{
487 488
	if (align > PAGE_SIZE) {
		printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
489
		       mod->name, align, PAGE_SIZE);
490 491 492
		align = PAGE_SIZE;
	}

493 494
	mod->percpu = __alloc_reserved_percpu(size, align);
	if (!mod->percpu) {
495
		printk(KERN_WARNING
Rusty Russell's avatar
Rusty Russell committed
496 497
		       "%s: Could not allocate %lu bytes percpu data\n",
		       mod->name, size);
498 499 500 501
		return -ENOMEM;
	}
	mod->percpu_size = size;
	return 0;
502 503
}

504
static void percpu_modfree(struct module *mod)
505
{
506
	free_percpu(mod->percpu);
507 508
}

509
static unsigned int find_pcpusec(struct load_info *info)
510
{
511
	return find_sec(info, ".data..percpu");
512 513
}

514 515
static void percpu_modcopy(struct module *mod,
			   const void *from, unsigned long size)
516 517 518 519
{
	int cpu;

	for_each_possible_cpu(cpu)
520
		memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
521 522
}

523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539
/**
 * is_module_percpu_address - test whether address is from module static percpu
 * @addr: address to test
 *
 * Test whether @addr belongs to module static percpu area.
 *
 * RETURNS:
 * %true if @addr is from module static percpu area
 */
bool is_module_percpu_address(unsigned long addr)
{
	struct module *mod;
	unsigned int cpu;

	preempt_disable();

	list_for_each_entry_rcu(mod, &modules, list) {
540 541
		if (mod->state == MODULE_STATE_UNFORMED)
			continue;
542 543 544 545 546 547 548 549 550 551 552 553 554 555 556
		if (!mod->percpu_size)
			continue;
		for_each_possible_cpu(cpu) {
			void *start = per_cpu_ptr(mod->percpu, cpu);

			if ((void *)addr >= start &&
			    (void *)addr < start + mod->percpu_size) {
				preempt_enable();
				return true;
			}
		}
	}

	preempt_enable();
	return false;
557 558
}

Linus Torvalds's avatar
Linus Torvalds committed
559
#else /* ... !CONFIG_SMP */
560

561
static inline void __percpu *mod_percpu(struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
562 563 564
{
	return NULL;
}
565 566 567 568 569 570
static inline int percpu_modalloc(struct module *mod,
				  unsigned long size, unsigned long align)
{
	return -ENOMEM;
}
static inline void percpu_modfree(struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
571 572
{
}
573
static unsigned int find_pcpusec(struct load_info *info)
Linus Torvalds's avatar
Linus Torvalds committed
574 575 576
{
	return 0;
}
577 578
static inline void percpu_modcopy(struct module *mod,
				  const void *from, unsigned long size)
Linus Torvalds's avatar
Linus Torvalds committed
579 580 581 582
{
	/* pcpusec should be 0, and size of that section should be 0. */
	BUG_ON(size != 0);
}
583 584 585 586
bool is_module_percpu_address(unsigned long addr)
{
	return false;
}
587

Linus Torvalds's avatar
Linus Torvalds committed
588 589
#endif /* CONFIG_SMP */

590 591 592 593 594 595
#define MODINFO_ATTR(field)	\
static void setup_modinfo_##field(struct module *mod, const char *s)  \
{                                                                     \
	mod->field = kstrdup(s, GFP_KERNEL);                          \
}                                                                     \
static ssize_t show_modinfo_##field(struct module_attribute *mattr,   \
596
			struct module_kobject *mk, char *buffer)      \
597
{                                                                     \
598
	return sprintf(buffer, "%s\n", mk->mod->field);               \
599 600 601 602 603 604 605
}                                                                     \
static int modinfo_##field##_exists(struct module *mod)               \
{                                                                     \
	return mod->field != NULL;                                    \
}                                                                     \
static void free_modinfo_##field(struct module *mod)                  \
{                                                                     \
606 607
	kfree(mod->field);                                            \
	mod->field = NULL;                                            \
608 609
}                                                                     \
static struct module_attribute modinfo_##field = {                    \
610
	.attr = { .name = __stringify(field), .mode = 0444 },         \
611 612 613 614 615 616 617 618 619
	.show = show_modinfo_##field,                                 \
	.setup = setup_modinfo_##field,                               \
	.test = modinfo_##field##_exists,                             \
	.free = free_modinfo_##field,                                 \
};

MODINFO_ATTR(version);
MODINFO_ATTR(srcversion);

620 621
static char last_unloaded_module[MODULE_NAME_LEN+1];

622
#ifdef CONFIG_MODULE_UNLOAD
623 624 625

EXPORT_TRACEPOINT_SYMBOL(module_get);

Linus Torvalds's avatar
Linus Torvalds committed
626
/* Init the unload section of the module. */
627
static int module_unload_init(struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
628
{
629 630 631 632
	mod->refptr = alloc_percpu(struct module_ref);
	if (!mod->refptr)
		return -ENOMEM;

633 634
	INIT_LIST_HEAD(&mod->source_list);
	INIT_LIST_HEAD(&mod->target_list);
635

Linus Torvalds's avatar
Linus Torvalds committed
636
	/* Hold reference count during initialization. */
637
	__this_cpu_write(mod->refptr->incs, 1);
Linus Torvalds's avatar
Linus Torvalds committed
638 639
	/* Backwards compatibility macros put refcount during init. */
	mod->waiter = current;
640 641

	return 0;
Linus Torvalds's avatar
Linus Torvalds committed
642 643 644 645 646 647 648
}

/* Does a already use b? */
static int already_uses(struct module *a, struct module *b)
{
	struct module_use *use;

649 650
	list_for_each_entry(use, &b->source_list, source_list) {
		if (use->source == a) {
651
			pr_debug("%s uses %s!\n", a->name, b->name);
Linus Torvalds's avatar
Linus Torvalds committed
652 653 654
			return 1;
		}
	}
655
	pr_debug("%s does not use %s!\n", a->name, b->name);
Linus Torvalds's avatar
Linus Torvalds committed
656 657 658
	return 0;
}

659 660 661 662 663 664 665 666 667 668 669
/*
 * Module a uses b
 *  - we add 'a' as a "source", 'b' as a "target" of module use
 *  - the module_use is added to the list of 'b' sources (so
 *    'b' can walk the list to see who sourced them), and of 'a'
 *    targets (so 'a' can see what modules it targets).
 */
static int add_module_usage(struct module *a, struct module *b)
{
	struct module_use *use;

670
	pr_debug("Allocating new usage for %s.\n", a->name);
671 672 673 674 675 676 677 678 679 680 681 682 683
	use = kmalloc(sizeof(*use), GFP_ATOMIC);
	if (!use) {
		printk(KERN_WARNING "%s: out of memory loading\n", a->name);
		return -ENOMEM;
	}

	use->source = a;
	use->target = b;
	list_add(&use->source_list, &b->source_list);
	list_add(&use->target_list, &a->target_list);
	return 0;
}

684
/* Module a uses b: caller needs module_mutex() */
685
int ref_module(struct module *a, struct module *b)
Linus Torvalds's avatar
Linus Torvalds committed
686
{
687
	int err;
Kay Sievers's avatar
Kay Sievers committed
688

689
	if (b == NULL || already_uses(a, b))
690 691
		return 0;

692 693
	/* If module isn't available, we fail. */
	err = strong_try_module_get(b);
694
	if (err)
695
		return err;
Linus Torvalds's avatar
Linus Torvalds committed
696

697 698
	err = add_module_usage(a, b);
	if (err) {
Linus Torvalds's avatar
Linus Torvalds committed
699
		module_put(b);
700
		return err;
Linus Torvalds's avatar
Linus Torvalds committed
701
	}
702
	return 0;
Linus Torvalds's avatar
Linus Torvalds committed
703
}
704
EXPORT_SYMBOL_GPL(ref_module);
Linus Torvalds's avatar
Linus Torvalds committed
705 706 707 708

/* Clear the unload stuff of the module. */
static void module_unload_free(struct module *mod)
{
709
	struct module_use *use, *tmp;
Linus Torvalds's avatar
Linus Torvalds committed
710

711
	mutex_lock(&module_mutex);
712 713
	list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
		struct module *i = use->target;
714
		pr_debug("%s unusing %s\n", mod->name, i->name);
715 716 717 718
		module_put(i);
		list_del(&use->source_list);
		list_del(&use->target_list);
		kfree(use);
Linus Torvalds's avatar
Linus Torvalds committed
719
	}
720
	mutex_unlock(&module_mutex);
721 722

	free_percpu(mod->refptr);
Linus Torvalds's avatar
Linus Torvalds committed
723 724 725
}

#ifdef CONFIG_MODULE_FORCE_UNLOAD
726
static inline int try_force_unload(unsigned int flags)
Linus Torvalds's avatar
Linus Torvalds committed
727 728 729
{
	int ret = (flags & O_TRUNC);
	if (ret)
730
		add_taint(TAINT_FORCED_RMMOD);
Linus Torvalds's avatar
Linus Torvalds committed
731 732 733
	return ret;
}
#else
734
static inline int try_force_unload(unsigned int flags)
Linus Torvalds's avatar
Linus Torvalds committed
735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751
{
	return 0;
}
#endif /* CONFIG_MODULE_FORCE_UNLOAD */

struct stopref
{
	struct module *mod;
	int flags;
	int *forced;
};

/* Whole machine is stopped with interrupts off when this runs. */
static int __try_stop_module(void *_sref)
{
	struct stopref *sref = _sref;

752 753
	/* If it's not unused, quit unless we're forcing. */
	if (module_refcount(sref->mod) != 0) {
754
		if (!(*sref->forced = try_force_unload(sref->flags)))
Linus Torvalds's avatar
Linus Torvalds committed
755 756 757 758 759 760 761 762 763 764
			return -EWOULDBLOCK;
	}

	/* Mark it as dying. */
	sref->mod->state = MODULE_STATE_GOING;
	return 0;
}

static int try_stop_module(struct module *mod, int flags, int *forced)
{
765 766
	if (flags & O_NONBLOCK) {
		struct stopref sref = { mod, flags, forced };
Linus Torvalds's avatar
Linus Torvalds committed
767

768
		return stop_machine(__try_stop_module, &sref, NULL);
769 770 771 772 773 774
	} else {
		/* We don't need to stop the machine for this. */
		mod->state = MODULE_STATE_GOING;
		synchronize_sched();
		return 0;
	}
Linus Torvalds's avatar
Linus Torvalds committed
775 776
}

777
unsigned long module_refcount(struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
778
{
779
	unsigned long incs = 0, decs = 0;
780
	int cpu;
Linus Torvalds's avatar
Linus Torvalds committed
781

782
	for_each_possible_cpu(cpu)
783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800
		decs += per_cpu_ptr(mod->refptr, cpu)->decs;
	/*
	 * ensure the incs are added up after the decs.
	 * module_put ensures incs are visible before decs with smp_wmb.
	 *
	 * This 2-count scheme avoids the situation where the refcount
	 * for CPU0 is read, then CPU0 increments the module refcount,
	 * then CPU1 drops that refcount, then the refcount for CPU1 is
	 * read. We would record a decrement but not its corresponding
	 * increment so we would see a low count (disaster).
	 *
	 * Rare situation? But module_refcount can be preempted, and we
	 * might be tallying up 4096+ CPUs. So it is not impossible.
	 */
	smp_rmb();
	for_each_possible_cpu(cpu)
		incs += per_cpu_ptr(mod->refptr, cpu)->incs;
	return incs - decs;
Linus Torvalds's avatar
Linus Torvalds committed
801 802 803 804 805 806 807 808
}
EXPORT_SYMBOL(module_refcount);

/* This exists whether we can unload or not */
static void free_module(struct module *mod);

static void wait_for_zero_refcount(struct module *mod)
{
809
	/* Since we might sleep for some time, release the mutex first */
810
	mutex_unlock(&module_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
811
	for (;;) {
812
		pr_debug("Looking at refcount...\n");
Linus Torvalds's avatar
Linus Torvalds committed
813 814 815 816 817 818
		set_current_state(TASK_UNINTERRUPTIBLE);
		if (module_refcount(mod) == 0)
			break;
		schedule();
	}
	current->state = TASK_RUNNING;
819
	mutex_lock(&module_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
820 821
}

822 823
SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
		unsigned int, flags)
Linus Torvalds's avatar
Linus Torvalds committed
824 825
{
	struct module *mod;
826
	char name[MODULE_NAME_LEN];
Linus Torvalds's avatar
Linus Torvalds committed
827 828
	int ret, forced = 0;

829
	if (!capable(CAP_SYS_MODULE) || modules_disabled)
830 831 832 833 834 835
		return -EPERM;

	if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
		return -EFAULT;
	name[MODULE_NAME_LEN-1] = '\0';

836 837
	if (mutex_lock_interruptible(&module_mutex) != 0)
		return -EINTR;
Linus Torvalds's avatar
Linus Torvalds committed
838 839 840 841 842 843 844

	mod = find_module(name);
	if (!mod) {
		ret = -ENOENT;
		goto out;
	}

845
	if (!list_empty(&mod->source_list)) {
Linus Torvalds's avatar
Linus Torvalds committed
846 847 848 849 850 851 852 853 854
		/* Other modules depend on us: get rid of them first. */
		ret = -EWOULDBLOCK;
		goto out;
	}

	/* Doing init or already dying? */
	if (mod->state != MODULE_STATE_LIVE) {
		/* FIXME: if (force), slam module count and wake up
                   waiter --RR */
855
		pr_debug("%s already dying\n", mod->name);
Linus Torvalds's avatar
Linus Torvalds committed
856 857 858 859 860
		ret = -EBUSY;
		goto out;
	}

	/* If it has an init func, it must have an exit func to unload */
861
	if (mod->init && !mod->exit) {
862
		forced = try_force_unload(flags);
Linus Torvalds's avatar
Linus Torvalds committed
863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881
		if (!forced) {
			/* This module can't be removed */
			ret = -EBUSY;
			goto out;
		}
	}

	/* Set this up before setting mod->state */
	mod->waiter = current;

	/* Stop the machine so refcounts can't move and disable module. */
	ret = try_stop_module(mod, flags, &forced);
	if (ret != 0)
		goto out;

	/* Never wait if forced. */
	if (!forced && module_refcount(mod) != 0)
		wait_for_zero_refcount(mod);

882
	mutex_unlock(&module_mutex);
Lucas De Marchi's avatar
Lucas De Marchi committed
883
	/* Final destruction now no one is using it. */
884
	if (mod->exit != NULL)
Linus Torvalds's avatar
Linus Torvalds committed
885
		mod->exit();
886 887
	blocking_notifier_call_chain(&module_notify_list,
				     MODULE_STATE_GOING, mod);
888
	async_synchronize_full();
889

890
	/* Store the name of the last unloaded module for diagnostic purposes */
891
	strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
Linus Torvalds's avatar
Linus Torvalds committed
892

893 894 895
	free_module(mod);
	return 0;
out:
896
	mutex_unlock(&module_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
897 898 899
	return ret;
}

900
static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
901 902 903 904
{
	struct module_use *use;
	int printed_something = 0;

905
	seq_printf(m, " %lu ", module_refcount(mod));
Linus Torvalds's avatar
Linus Torvalds committed
906 907 908

	/* Always include a trailing , so userspace can differentiate
           between this and the old multi-field proc format. */
909
	list_for_each_entry(use, &mod->source_list, source_list) {
Linus Torvalds's avatar
Linus Torvalds committed
910
		printed_something = 1;
911
		seq_printf(m, "%s,", use->source->name);
Linus Torvalds's avatar
Linus Torvalds committed
912 913 914 915 916 917 918 919 920 921 922 923 924 925 926
	}

	if (mod->init != NULL && mod->exit == NULL) {
		printed_something = 1;
		seq_printf(m, "[permanent],");
	}

	if (!printed_something)
		seq_printf(m, "-");
}

void __symbol_put(const char *symbol)
{
	struct module *owner;

Rusty Russell's avatar
Rusty Russell committed
927
	preempt_disable();
928
	if (!find_symbol(symbol, &owner, NULL, true, false))
Linus Torvalds's avatar
Linus Torvalds committed
929 930
		BUG();
	module_put(owner);
Rusty Russell's avatar
Rusty Russell committed
931
	preempt_enable();
Linus Torvalds's avatar
Linus Torvalds committed
932 933 934
}
EXPORT_SYMBOL(__symbol_put);

935
/* Note this assumes addr is a function, which it currently always is. */
Linus Torvalds's avatar
Linus Torvalds committed
936 937
void symbol_put_addr(void *addr)
{
938
	struct module *modaddr;
939
	unsigned long a = (unsigned long)dereference_function_descriptor(addr);
Linus Torvalds's avatar
Linus Torvalds committed
940

941
	if (core_kernel_text(a))
942
		return;
Linus Torvalds's avatar
Linus Torvalds committed
943

944 945
	/* module_text_address is safe here: we're supposed to have reference
	 * to module from symbol_get, so it can't go away. */
946
	modaddr = __module_text_address(a);
947
	BUG_ON(!modaddr);
948
	module_put(modaddr);
Linus Torvalds's avatar
Linus Torvalds committed
949 950 951 952
}
EXPORT_SYMBOL_GPL(symbol_put_addr);

static ssize_t show_refcnt(struct module_attribute *mattr,
953
			   struct module_kobject *mk, char *buffer)
Linus Torvalds's avatar
Linus Torvalds committed
954
{
955
	return sprintf(buffer, "%lu\n", module_refcount(mk->mod));
Linus Torvalds's avatar
Linus Torvalds committed
956 957
}

958 959
static struct module_attribute modinfo_refcnt =
	__ATTR(refcnt, 0444, show_refcnt, NULL);
Linus Torvalds's avatar
Linus Torvalds committed
960

961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990
void __module_get(struct module *module)
{
	if (module) {
		preempt_disable();
		__this_cpu_inc(module->refptr->incs);
		trace_module_get(module, _RET_IP_);
		preempt_enable();
	}
}
EXPORT_SYMBOL(__module_get);

bool try_module_get(struct module *module)
{
	bool ret = true;

	if (module) {
		preempt_disable();

		if (likely(module_is_live(module))) {
			__this_cpu_inc(module->refptr->incs);
			trace_module_get(module, _RET_IP_);
		} else
			ret = false;

		preempt_enable();
	}
	return ret;
}
EXPORT_SYMBOL(try_module_get);

Al Viro's avatar
Al Viro committed
991 992 993
void module_put(struct module *module)
{
	if (module) {
994
		preempt_disable();
995 996
		smp_wmb(); /* see comment in module_refcount */
		__this_cpu_inc(module->refptr->decs);
997

998
		trace_module_put(module, _RET_IP_);
Al Viro's avatar
Al Viro committed
999 1000 1001
		/* Maybe they're waiting for us to drop reference? */
		if (unlikely(!module_is_live(module)))
			wake_up_process(module->waiter);
1002
		preempt_enable();
Al Viro's avatar
Al Viro committed
1003 1004 1005 1006
	}
}
EXPORT_SYMBOL(module_put);

Linus Torvalds's avatar
Linus Torvalds committed
1007
#else /* !CONFIG_MODULE_UNLOAD */
1008
static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
1009 1010 1011 1012 1013 1014 1015 1016 1017
{
	/* We don't know the usage count, or what modules are using. */
	seq_printf(m, " - -");
}

static inline void module_unload_free(struct module *mod)
{
}

1018
int ref_module(struct module *a, struct module *b)
Linus Torvalds's avatar
Linus Torvalds committed
1019
{
1020
	return strong_try_module_get(b);
Linus Torvalds's avatar
Linus Torvalds committed
1021
}
1022
EXPORT_SYMBOL_GPL(ref_module);
Linus Torvalds's avatar
Linus Torvalds committed
1023

1024
static inline int module_unload_init(struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
1025
{
1026
	return 0;
Linus Torvalds's avatar
Linus Torvalds committed
1027 1028 1029
}
#endif /* CONFIG_MODULE_UNLOAD */

1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049
static size_t module_flags_taint(struct module *mod, char *buf)
{
	size_t l = 0;

	if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
		buf[l++] = 'P';
	if (mod->taints & (1 << TAINT_OOT_MODULE))
		buf[l++] = 'O';
	if (mod->taints & (1 << TAINT_FORCED_MODULE))
		buf[l++] = 'F';
	if (mod->taints & (1 << TAINT_CRAP))
		buf[l++] = 'C';
	/*
	 * TAINT_FORCED_RMMOD: could be added.
	 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
	 * apply to modules.
	 */
	return l;
}

1050
static ssize_t show_initstate(struct module_attribute *mattr,
1051
			      struct module_kobject *mk, char *buffer)
1052 1053 1054
{
	const char *state = "unknown";

1055
	switch (mk->mod->state) {
1056 1057 1058 1059 1060 1061 1062 1063 1064
	case MODULE_STATE_LIVE:
		state = "live";
		break;
	case MODULE_STATE_COMING:
		state = "coming";
		break;
	case MODULE_STATE_GOING:
		state = "going";
		break;
1065 1066
	default:
		BUG();
1067 1068 1069 1070
	}
	return sprintf(buffer, "%s\n", state);
}

1071 1072
static struct module_attribute modinfo_initstate =
	__ATTR(initstate, 0444, show_initstate, NULL);
1073

1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084
static ssize_t store_uevent(struct module_attribute *mattr,
			    struct module_kobject *mk,
			    const char *buffer, size_t count)
{
	enum kobject_action action;

	if (kobject_action_type(buffer, count, &action) == 0)
		kobject_uevent(&mk->kobj, action);
	return count;
}

1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117
struct module_attribute module_uevent =
	__ATTR(uevent, 0200, NULL, store_uevent);

static ssize_t show_coresize(struct module_attribute *mattr,
			     struct module_kobject *mk, char *buffer)
{
	return sprintf(buffer, "%u\n", mk->mod->core_size);
}

static struct module_attribute modinfo_coresize =
	__ATTR(coresize, 0444, show_coresize, NULL);

static ssize_t show_initsize(struct module_attribute *mattr,
			     struct module_kobject *mk, char *buffer)
{
	return sprintf(buffer, "%u\n", mk->mod->init_size);
}

static struct module_attribute modinfo_initsize =
	__ATTR(initsize, 0444, show_initsize, NULL);

static ssize_t show_taint(struct module_attribute *mattr,
			  struct module_kobject *mk, char *buffer)
{
	size_t l;

	l = module_flags_taint(mk->mod, buffer);
	buffer[l++] = '\n';
	return l;
}

static struct module_attribute modinfo_taint =
	__ATTR(taint, 0444, show_taint, NULL);
1118

1119
static struct module_attribute *modinfo_attrs[] = {
1120
	&module_uevent,
1121 1122
	&modinfo_version,
	&modinfo_srcversion,
1123 1124 1125 1126
	&modinfo_initstate,
	&modinfo_coresize,
	&modinfo_initsize,
	&modinfo_taint,
1127
#ifdef CONFIG_MODULE_UNLOAD
1128
	&modinfo_refcnt,
1129 1130 1131 1132
#endif
	NULL,
};

Linus Torvalds's avatar
Linus Torvalds committed
1133 1134
static const char vermagic[] = VERMAGIC_STRING;

1135
static int try_to_force_load(struct module *mod, const char *reason)
1136 1137
{
#ifdef CONFIG_MODULE_FORCE_LOAD
Andi Kleen's avatar
Andi Kleen committed
1138
	if (!test_taint(TAINT_FORCED_MODULE))
1139 1140
		printk(KERN_WARNING "%s: %s: kernel tainted.\n",
		       mod->name, reason);
1141 1142 1143 1144 1145 1146 1147
	add_taint_module(mod, TAINT_FORCED_MODULE);
	return 0;
#else
	return -ENOEXEC;
#endif
}

Linus Torvalds's avatar
Linus Torvalds committed
1148
#ifdef CONFIG_MODVERSIONS
1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159
/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
static unsigned long maybe_relocated(unsigned long crc,
				     const struct module *crc_owner)
{
#ifdef ARCH_RELOCATES_KCRCTAB
	if (crc_owner == NULL)
		return crc - (unsigned long)reloc_start;
#endif
	return crc;
}

Linus Torvalds's avatar
Linus Torvalds committed
1160 1161 1162 1163
static int check_version(Elf_Shdr *sechdrs,
			 unsigned int versindex,
			 const char *symname,
			 struct module *mod, 
1164 1165
			 const unsigned long *crc,
			 const struct module *crc_owner)
Linus Torvalds's avatar
Linus Torvalds committed
1166 1167 1168 1169 1170 1171 1172 1173
{
	unsigned int i, num_versions;
	struct modversion_info *versions;

	/* Exporting module didn't supply crcs?  OK, we're already tainted. */
	if (!crc)
		return 1;

1174 1175 1176 1177
	/* No versions at all?  modprobe --force does this. */
	if (versindex == 0)
		return try_to_force_load(mod, symname) == 0;

Linus Torvalds's avatar
Linus Torvalds committed
1178 1179 1180 1181 1182 1183 1184 1185
	versions = (void *) sechdrs[versindex].sh_addr;
	num_versions = sechdrs[versindex].sh_size
		/ sizeof(struct modversion_info);

	for (i = 0; i < num_versions; i++) {
		if (strcmp(versions[i].name, symname) != 0)
			continue;

1186
		if (versions[i].crc == maybe_relocated(*crc, crc_owner))
Linus Torvalds's avatar
Linus Torvalds committed
1187
			return 1;
1188
		pr_debug("Found checksum %lX vs module %lX\n",
1189
		       maybe_relocated(*crc, crc_owner), versions[i].crc);
1190
		goto bad_version;
Linus Torvalds's avatar
Linus Torvalds committed
1191
	}
1192

1193 1194 1195
	printk(KERN_WARNING "%s: no symbol version for %s\n",
	       mod->name, symname);
	return 0;
1196 1197 1198 1199 1200

bad_version:
	printk("%s: disagrees about version of symbol %s\n",
	       mod->name, symname);
	return 0;
Linus Torvalds's avatar
Linus Torvalds committed
1201 1202 1203 1204 1205 1206 1207 1208
}

static inline int check_modstruct_version(Elf_Shdr *sechdrs,
					  unsigned int versindex,
					  struct module *mod)
{
	const unsigned long *crc;

1209 1210
	/* Since this should be found in kernel (which can't be removed),
	 * no locking is necessary. */
1211 1212
	if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
			 &crc, true, false))
Linus Torvalds's avatar
Linus Torvalds committed
1213
		BUG();
1214 1215
	return check_version(sechdrs, versindex, "module_layout", mod, crc,
			     NULL);
Linus Torvalds's avatar
Linus Torvalds committed
1216 1217
}

1218 1219 1220
/* First part is kernel version, which we ignore if module has crcs. */
static inline int same_magic(const char *amagic, const char *bmagic,
			     bool has_crcs)
Linus Torvalds's avatar
Linus Torvalds committed
1221
{
1222 1223 1224 1225
	if (has_crcs) {
		amagic += strcspn(amagic, " ");
		bmagic += strcspn(bmagic, " ");
	}
Linus Torvalds's avatar
Linus Torvalds committed
1226 1227 1228 1229 1230 1231 1232
	return strcmp(amagic, bmagic) == 0;
}
#else
static inline int check_version(Elf_Shdr *sechdrs,
				unsigned int versindex,
				const char *symname,
				struct module *mod, 
1233 1234
				const unsigned long *crc,
				const struct module *crc_owner)
Linus Torvalds's avatar
Linus Torvalds committed
1235 1236 1237