module.c 78.7 KB
Newer Older
1
/*
Linus Torvalds's avatar
Linus Torvalds committed
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
   Copyright (C) 2002 Richard Henderson
   Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.

    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
*/
#include <linux/module.h>
#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/fs.h>
Roland McGrath's avatar
Roland McGrath committed
25
#include <linux/sysfs.h>
26
#include <linux/kernel.h>
Linus Torvalds's avatar
Linus Torvalds committed
27 28 29
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/elf.h>
30
#include <linux/proc_fs.h>
Linus Torvalds's avatar
Linus Torvalds committed
31 32 33 34
#include <linux/seq_file.h>
#include <linux/syscalls.h>
#include <linux/fcntl.h>
#include <linux/rcupdate.h>
35
#include <linux/capability.h>
Linus Torvalds's avatar
Linus Torvalds committed
36 37 38 39 40 41
#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
42
#include <linux/sched.h>
Linus Torvalds's avatar
Linus Torvalds committed
43 44
#include <linux/stop_machine.h>
#include <linux/device.h>
45
#include <linux/string.h>
Arjan van de Ven's avatar
Arjan van de Ven committed
46
#include <linux/mutex.h>
47
#include <linux/rculist.h>
Linus Torvalds's avatar
Linus Torvalds committed
48 49
#include <asm/uaccess.h>
#include <asm/cacheflush.h>
50
#include <asm/mmu_context.h>
51
#include <linux/license.h>
52
#include <asm/sections.h>
53
#include <linux/tracepoint.h>
54
#include <linux/ftrace.h>
55
#include <linux/async.h>
56
#include <linux/percpu.h>
57
#include <linux/kmemleak.h>
Linus Torvalds's avatar
Linus Torvalds committed
58

59 60 61
#define CREATE_TRACE_POINTS
#include <trace/events/module.h>

Linus Torvalds's avatar
Linus Torvalds committed
62 63 64 65 66 67 68 69 70 71 72 73 74
#if 0
#define DEBUGP printk
#else
#define DEBUGP(fmt , a...)
#endif

#ifndef ARCH_SHF_SMALL
#define ARCH_SHF_SMALL 0
#endif

/* If this is set, the section belongs in the init part of the module */
#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))

Rusty Russell's avatar
Rusty Russell committed
75
/* List of modules, protected by module_mutex or preempt_disable
76
 * (delete uses stop_machine/add uses RCU list operations). */
77 78
DEFINE_MUTEX(module_mutex);
EXPORT_SYMBOL_GPL(module_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
79 80
static LIST_HEAD(modules);

81 82 83
/* Block module loading/unloading? */
int modules_disabled = 0;

84 85 86
/* Waiting for a module to finish initializing? */
static DECLARE_WAIT_QUEUE_HEAD(module_wq);

87
static BLOCKING_NOTIFIER_HEAD(module_notify_list);
Linus Torvalds's avatar
Linus Torvalds committed
88

Rusty Russell's avatar
Rusty Russell committed
89
/* Bounds of module allocation, for speeding __module_address */
90 91
static unsigned long module_addr_min = -1UL, module_addr_max = 0;

Linus Torvalds's avatar
Linus Torvalds committed
92 93
int register_module_notifier(struct notifier_block * nb)
{
94
	return blocking_notifier_chain_register(&module_notify_list, nb);
Linus Torvalds's avatar
Linus Torvalds committed
95 96 97 98 99
}
EXPORT_SYMBOL(register_module_notifier);

int unregister_module_notifier(struct notifier_block * nb)
{
100
	return blocking_notifier_chain_unregister(&module_notify_list, nb);
Linus Torvalds's avatar
Linus Torvalds committed
101 102 103
}
EXPORT_SYMBOL(unregister_module_notifier);

104 105
/* 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
106 107 108
static inline int strong_try_module_get(struct module *mod)
{
	if (mod && mod->state == MODULE_STATE_COMING)
109 110
		return -EBUSY;
	if (try_module_get(mod))
Linus Torvalds's avatar
Linus Torvalds committed
111
		return 0;
112 113
	else
		return -ENOENT;
Linus Torvalds's avatar
Linus Torvalds committed
114 115
}

116 117 118
static inline void add_taint_module(struct module *mod, unsigned flag)
{
	add_taint(flag);
Andi Kleen's avatar
Andi Kleen committed
119
	mod->taints |= (1U << flag);
120 121
}

122 123 124
/*
 * 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
125 126 127 128 129 130 131
 */
void __module_put_and_exit(struct module *mod, long code)
{
	module_put(mod);
	do_exit(code);
}
EXPORT_SYMBOL(__module_put_and_exit);
132

Linus Torvalds's avatar
Linus Torvalds committed
133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148
/* Find a module section: 0 means not found. */
static unsigned int find_sec(Elf_Ehdr *hdr,
			     Elf_Shdr *sechdrs,
			     const char *secstrings,
			     const char *name)
{
	unsigned int i;

	for (i = 1; i < hdr->e_shnum; i++)
		/* Alloc bit cleared means "ignore it." */
		if ((sechdrs[i].sh_flags & SHF_ALLOC)
		    && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
			return i;
	return 0;
}

Rusty Russell's avatar
Rusty Russell committed
149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171
/* Find a module section, or NULL. */
static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
			  const char *secstrings, const char *name)
{
	/* Section 0 has sh_addr 0. */
	return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
}

/* Find a module section, or NULL.  Fill in number of "objects" in section. */
static void *section_objs(Elf_Ehdr *hdr,
			  Elf_Shdr *sechdrs,
			  const char *secstrings,
			  const char *name,
			  size_t object_size,
			  unsigned int *num)
{
	unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);

	/* Section 0 has sh_addr 0 and sh_size 0. */
	*num = sechdrs[sec].sh_size / object_size;
	return (void *)sechdrs[sec].sh_addr;
}

Linus Torvalds's avatar
Linus Torvalds committed
172 173 174 175 176
/* 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[];
177 178
extern const struct kernel_symbol __start___ksymtab_gpl_future[];
extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
179 180
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
181 182
extern const unsigned long __start___kcrctab[];
extern const unsigned long __start___kcrctab_gpl[];
183
extern const unsigned long __start___kcrctab_gpl_future[];
184 185 186 187 188
#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[];
189 190
extern const unsigned long __start___kcrctab_unused[];
extern const unsigned long __start___kcrctab_unused_gpl[];
191
#endif
Linus Torvalds's avatar
Linus Torvalds committed
192 193 194 195

#ifndef CONFIG_MODVERSIONS
#define symversion(base, idx) NULL
#else
Andrew Morton's avatar
Andrew Morton committed
196
#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
Linus Torvalds's avatar
Linus Torvalds committed
197 198
#endif

199 200 201 202 203 204 205
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,
					      unsigned int symnum, void *data),
				   void *data)
206
{
207
	unsigned int i, j;
208

209 210 211 212
	for (j = 0; j < arrsize; j++) {
		for (i = 0; i < arr[j].stop - arr[j].start; i++)
			if (fn(&arr[j], owner, i, data))
				return true;
213
	}
214 215

	return false;
216 217
}

218
/* Returns true as soon as fn returns true, otherwise false. */
219 220
bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
			    unsigned int symnum, void *data), void *data)
221 222 223 224
{
	struct module *mod;
	const struct symsearch arr[] = {
		{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
225
		  NOT_GPL_ONLY, false },
226
		{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
227 228
		  __start___kcrctab_gpl,
		  GPL_ONLY, false },
229
		{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
230 231
		  __start___kcrctab_gpl_future,
		  WILL_BE_GPL_ONLY, false },
232
#ifdef CONFIG_UNUSED_SYMBOLS
233
		{ __start___ksymtab_unused, __stop___ksymtab_unused,
234 235
		  __start___kcrctab_unused,
		  NOT_GPL_ONLY, true },
236
		{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
237 238
		  __start___kcrctab_unused_gpl,
		  GPL_ONLY, true },
239
#endif
240
	};
241

242 243
	if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
		return true;
244

245
	list_for_each_entry_rcu(mod, &modules, list) {
246 247
		struct symsearch arr[] = {
			{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
248
			  NOT_GPL_ONLY, false },
249
			{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
250 251
			  mod->gpl_crcs,
			  GPL_ONLY, false },
252 253
			{ mod->gpl_future_syms,
			  mod->gpl_future_syms + mod->num_gpl_future_syms,
254 255
			  mod->gpl_future_crcs,
			  WILL_BE_GPL_ONLY, false },
256
#ifdef CONFIG_UNUSED_SYMBOLS
257 258
			{ mod->unused_syms,
			  mod->unused_syms + mod->num_unused_syms,
259 260
			  mod->unused_crcs,
			  NOT_GPL_ONLY, true },
261 262
			{ mod->unused_gpl_syms,
			  mod->unused_gpl_syms + mod->num_unused_gpl_syms,
263 264
			  mod->unused_gpl_crcs,
			  GPL_ONLY, true },
265
#endif
266 267
		};

268 269 270 271 272
		if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
			return true;
	}
	return false;
}
273
EXPORT_SYMBOL_GPL(each_symbol);
274 275 276 277 278 279 280 281 282 283

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

	/* Output */
	struct module *owner;
	const unsigned long *crc;
284
	const struct kernel_symbol *sym;
285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305
};

static bool find_symbol_in_section(const struct symsearch *syms,
				   struct module *owner,
				   unsigned int symnum, void *data)
{
	struct find_symbol_arg *fsa = data;

	if (strcmp(syms->start[symnum].name, fsa->name) != 0)
		return false;

	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);
			printk(KERN_WARNING "Please see the file "
			       "Documentation/feature-removal-schedule.txt "
			       "in the kernel source tree for more details.\n");
306
		}
Linus Torvalds's avatar
Linus Torvalds committed
307
	}
308

309
#ifdef CONFIG_UNUSED_SYMBOLS
310 311 312 313 314 315 316 317 318 319 320
	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");
	}
321
#endif
322 323 324

	fsa->owner = owner;
	fsa->crc = symversion(syms->crcs, symnum);
325
	fsa->sym = &syms->start[symnum];
326 327 328
	return true;
}

329 330
/* Find a symbol and return it, along with, (optional) crc and
 * (optional) module which owns it */
331 332 333 334 335
const struct kernel_symbol *find_symbol(const char *name,
					struct module **owner,
					const unsigned long **crc,
					bool gplok,
					bool warn)
336 337 338 339 340 341 342 343 344 345 346 347
{
	struct find_symbol_arg fsa;

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

	if (each_symbol(find_symbol_in_section, &fsa)) {
		if (owner)
			*owner = fsa.owner;
		if (crc)
			*crc = fsa.crc;
348
		return fsa.sym;
349 350
	}

Linus Torvalds's avatar
Linus Torvalds committed
351
	DEBUGP("Failed to find symbol %s\n", name);
352
	return NULL;
Linus Torvalds's avatar
Linus Torvalds committed
353
}
354
EXPORT_SYMBOL_GPL(find_symbol);
Linus Torvalds's avatar
Linus Torvalds committed
355 356

/* Search for module by name: must hold module_mutex. */
357
struct module *find_module(const char *name)
Linus Torvalds's avatar
Linus Torvalds committed
358 359 360 361 362 363 364 365 366
{
	struct module *mod;

	list_for_each_entry(mod, &modules, list) {
		if (strcmp(mod->name, name) == 0)
			return mod;
	}
	return NULL;
}
367
EXPORT_SYMBOL_GPL(find_module);
Linus Torvalds's avatar
Linus Torvalds committed
368 369

#ifdef CONFIG_SMP
370

371
static inline void __percpu *mod_percpu(struct module *mod)
372
{
373 374
	return mod->percpu;
}
375

376 377 378
static int percpu_modalloc(struct module *mod,
			   unsigned long size, unsigned long align)
{
379 380
	if (align > PAGE_SIZE) {
		printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
381
		       mod->name, align, PAGE_SIZE);
382 383 384
		align = PAGE_SIZE;
	}

385 386
	mod->percpu = __alloc_reserved_percpu(size, align);
	if (!mod->percpu) {
387 388
		printk(KERN_WARNING
		       "Could not allocate %lu bytes percpu data\n", size);
389 390 391 392
		return -ENOMEM;
	}
	mod->percpu_size = size;
	return 0;
393 394
}

395
static void percpu_modfree(struct module *mod)
396
{
397
	free_percpu(mod->percpu);
398 399
}

400 401 402 403 404 405 406
static unsigned int find_pcpusec(Elf_Ehdr *hdr,
				 Elf_Shdr *sechdrs,
				 const char *secstrings)
{
	return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
}

407 408
static void percpu_modcopy(struct module *mod,
			   const void *from, unsigned long size)
409 410 411 412
{
	int cpu;

	for_each_possible_cpu(cpu)
413
		memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
414 415
}

416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447
/**
 * 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) {
		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;
448 449
}

Linus Torvalds's avatar
Linus Torvalds committed
450
#else /* ... !CONFIG_SMP */
451

452
static inline void __percpu *mod_percpu(struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
453 454 455
{
	return NULL;
}
456 457 458 459 460 461
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
462 463 464 465 466 467 468 469
{
}
static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
					Elf_Shdr *sechdrs,
					const char *secstrings)
{
	return 0;
}
470 471
static inline void percpu_modcopy(struct module *mod,
				  const void *from, unsigned long size)
Linus Torvalds's avatar
Linus Torvalds committed
472 473 474 475
{
	/* pcpusec should be 0, and size of that section should be 0. */
	BUG_ON(size != 0);
}
476 477 478 479
bool is_module_percpu_address(unsigned long addr)
{
	return false;
}
480

Linus Torvalds's avatar
Linus Torvalds committed
481 482
#endif /* CONFIG_SMP */

483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498
#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,   \
	                struct module *mod, char *buffer)             \
{                                                                     \
	return sprintf(buffer, "%s\n", mod->field);                   \
}                                                                     \
static int modinfo_##field##_exists(struct module *mod)               \
{                                                                     \
	return mod->field != NULL;                                    \
}                                                                     \
static void free_modinfo_##field(struct module *mod)                  \
{                                                                     \
499 500
	kfree(mod->field);                                            \
	mod->field = NULL;                                            \
501 502
}                                                                     \
static struct module_attribute modinfo_##field = {                    \
503
	.attr = { .name = __stringify(field), .mode = 0444 },         \
504 505 506 507 508 509 510 511 512
	.show = show_modinfo_##field,                                 \
	.setup = setup_modinfo_##field,                               \
	.test = modinfo_##field##_exists,                             \
	.free = free_modinfo_##field,                                 \
};

MODINFO_ATTR(version);
MODINFO_ATTR(srcversion);

513 514
static char last_unloaded_module[MODULE_NAME_LEN+1];

515
#ifdef CONFIG_MODULE_UNLOAD
516 517 518

EXPORT_TRACEPOINT_SYMBOL(module_get);

Linus Torvalds's avatar
Linus Torvalds committed
519 520 521
/* Init the unload section of the module. */
static void module_unload_init(struct module *mod)
{
522
	int cpu;
Linus Torvalds's avatar
Linus Torvalds committed
523 524

	INIT_LIST_HEAD(&mod->modules_which_use_me);
525 526 527 528
	for_each_possible_cpu(cpu) {
		per_cpu_ptr(mod->refptr, cpu)->incs = 0;
		per_cpu_ptr(mod->refptr, cpu)->decs = 0;
	}
529

Linus Torvalds's avatar
Linus Torvalds committed
530
	/* Hold reference count during initialization. */
531
	__this_cpu_write(mod->refptr->incs, 1);
Linus Torvalds's avatar
Linus Torvalds committed
532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558
	/* Backwards compatibility macros put refcount during init. */
	mod->waiter = current;
}

/* modules using other modules */
struct module_use
{
	struct list_head list;
	struct module *module_which_uses;
};

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

	list_for_each_entry(use, &b->modules_which_use_me, list) {
		if (use->module_which_uses == a) {
			DEBUGP("%s uses %s!\n", a->name, b->name);
			return 1;
		}
	}
	DEBUGP("%s does not use %s!\n", a->name, b->name);
	return 0;
}

/* Module a uses b */
559
int use_module(struct module *a, struct module *b)
Linus Torvalds's avatar
Linus Torvalds committed
560 561
{
	struct module_use *use;
562
	int no_warn, err;
Kay Sievers's avatar
Kay Sievers committed
563

Linus Torvalds's avatar
Linus Torvalds committed
564 565
	if (b == NULL || already_uses(a, b)) return 1;

566 567 568 569 570 571 572 573 574 575 576
	/* If we're interrupted or time out, we fail. */
	if (wait_event_interruptible_timeout(
		    module_wq, (err = strong_try_module_get(b)) != -EBUSY,
		    30 * HZ) <= 0) {
		printk("%s: gave up waiting for init of module %s.\n",
		       a->name, b->name);
		return 0;
	}

	/* If strong_try_module_get() returned a different error, we fail. */
	if (err)
Linus Torvalds's avatar
Linus Torvalds committed
577 578 579 580 581 582 583 584 585 586 587 588
		return 0;

	DEBUGP("Allocating new usage for %s.\n", a->name);
	use = kmalloc(sizeof(*use), GFP_ATOMIC);
	if (!use) {
		printk("%s: out of memory loading\n", a->name);
		module_put(b);
		return 0;
	}

	use->module_which_uses = a;
	list_add(&use->list, &b->modules_which_use_me);
Kay Sievers's avatar
Kay Sievers committed
589
	no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
Linus Torvalds's avatar
Linus Torvalds committed
590 591
	return 1;
}
592
EXPORT_SYMBOL_GPL(use_module);
Linus Torvalds's avatar
Linus Torvalds committed
593 594 595 596 597 598 599 600 601 602 603 604 605 606 607

/* Clear the unload stuff of the module. */
static void module_unload_free(struct module *mod)
{
	struct module *i;

	list_for_each_entry(i, &modules, list) {
		struct module_use *use;

		list_for_each_entry(use, &i->modules_which_use_me, list) {
			if (use->module_which_uses == mod) {
				DEBUGP("%s unusing %s\n", mod->name, i->name);
				module_put(i);
				list_del(&use->list);
				kfree(use);
Kay Sievers's avatar
Kay Sievers committed
608
				sysfs_remove_link(i->holders_dir, mod->name);
Linus Torvalds's avatar
Linus Torvalds committed
609 610 611 612 613 614 615 616
				/* There can be at most one match. */
				break;
			}
		}
	}
}

#ifdef CONFIG_MODULE_FORCE_UNLOAD
617
static inline int try_force_unload(unsigned int flags)
Linus Torvalds's avatar
Linus Torvalds committed
618 619 620
{
	int ret = (flags & O_TRUNC);
	if (ret)
621
		add_taint(TAINT_FORCED_RMMOD);
Linus Torvalds's avatar
Linus Torvalds committed
622 623 624
	return ret;
}
#else
625
static inline int try_force_unload(unsigned int flags)
Linus Torvalds's avatar
Linus Torvalds committed
626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642
{
	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;

643 644
	/* If it's not unused, quit unless we're forcing. */
	if (module_refcount(sref->mod) != 0) {
645
		if (!(*sref->forced = try_force_unload(sref->flags)))
Linus Torvalds's avatar
Linus Torvalds committed
646 647 648 649 650 651 652 653 654 655
			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)
{
656 657
	if (flags & O_NONBLOCK) {
		struct stopref sref = { mod, flags, forced };
Linus Torvalds's avatar
Linus Torvalds committed
658

659
		return stop_machine(__try_stop_module, &sref, NULL);
660 661 662 663 664 665
	} 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
666 667 668 669
}

unsigned int module_refcount(struct module *mod)
{
670
	unsigned int incs = 0, decs = 0;
671
	int cpu;
Linus Torvalds's avatar
Linus Torvalds committed
672

673
	for_each_possible_cpu(cpu)
674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691
		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
692 693 694 695 696 697 698 699
}
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)
{
700
	/* Since we might sleep for some time, release the mutex first */
701
	mutex_unlock(&module_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
702 703 704 705 706 707 708 709
	for (;;) {
		DEBUGP("Looking at refcount...\n");
		set_current_state(TASK_UNINTERRUPTIBLE);
		if (module_refcount(mod) == 0)
			break;
		schedule();
	}
	current->state = TASK_RUNNING;
710
	mutex_lock(&module_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
711 712
}

713 714
SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
		unsigned int, flags)
Linus Torvalds's avatar
Linus Torvalds committed
715 716
{
	struct module *mod;
717
	char name[MODULE_NAME_LEN];
Linus Torvalds's avatar
Linus Torvalds committed
718 719
	int ret, forced = 0;

720
	if (!capable(CAP_SYS_MODULE) || modules_disabled)
721 722 723 724 725 726
		return -EPERM;

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

727 728
	if (mutex_lock_interruptible(&module_mutex) != 0)
		return -EINTR;
Linus Torvalds's avatar
Linus Torvalds committed
729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751

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

	if (!list_empty(&mod->modules_which_use_me)) {
		/* 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 */
		DEBUGP("%s already dying\n", mod->name);
		ret = -EBUSY;
		goto out;
	}

	/* If it has an init func, it must have an exit func to unload */
752
	if (mod->init && !mod->exit) {
753
		forced = try_force_unload(flags);
Linus Torvalds's avatar
Linus Torvalds committed
754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772
		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);

773
	mutex_unlock(&module_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
774
	/* Final destruction now noone is using it. */
775
	if (mod->exit != NULL)
Linus Torvalds's avatar
Linus Torvalds committed
776
		mod->exit();
777 778
	blocking_notifier_call_chain(&module_notify_list,
				     MODULE_STATE_GOING, mod);
779
	async_synchronize_full();
780
	mutex_lock(&module_mutex);
781
	/* Store the name of the last unloaded module for diagnostic purposes */
782
	strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
783
	ddebug_remove_module(mod->name);
Linus Torvalds's avatar
Linus Torvalds committed
784 785 786
	free_module(mod);

 out:
787
	mutex_unlock(&module_mutex);
Linus Torvalds's avatar
Linus Torvalds committed
788 789 790
	return ret;
}

791
static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817
{
	struct module_use *use;
	int printed_something = 0;

	seq_printf(m, " %u ", module_refcount(mod));

	/* Always include a trailing , so userspace can differentiate
           between this and the old multi-field proc format. */
	list_for_each_entry(use, &mod->modules_which_use_me, list) {
		printed_something = 1;
		seq_printf(m, "%s,", use->module_which_uses->name);
	}

	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
818
	preempt_disable();
819
	if (!find_symbol(symbol, &owner, NULL, true, false))
Linus Torvalds's avatar
Linus Torvalds committed
820 821
		BUG();
	module_put(owner);
Rusty Russell's avatar
Rusty Russell committed
822
	preempt_enable();
Linus Torvalds's avatar
Linus Torvalds committed
823 824 825
}
EXPORT_SYMBOL(__symbol_put);

826
/* Note this assumes addr is a function, which it currently always is. */
Linus Torvalds's avatar
Linus Torvalds committed
827 828
void symbol_put_addr(void *addr)
{
829
	struct module *modaddr;
830
	unsigned long a = (unsigned long)dereference_function_descriptor(addr);
Linus Torvalds's avatar
Linus Torvalds committed
831

832
	if (core_kernel_text(a))
833
		return;
Linus Torvalds's avatar
Linus Torvalds committed
834

835 836
	/* module_text_address is safe here: we're supposed to have reference
	 * to module from symbol_get, so it can't go away. */
837
	modaddr = __module_text_address(a);
838
	BUG_ON(!modaddr);
839
	module_put(modaddr);
Linus Torvalds's avatar
Linus Torvalds committed
840 841 842 843 844 845
}
EXPORT_SYMBOL_GPL(symbol_put_addr);

static ssize_t show_refcnt(struct module_attribute *mattr,
			   struct module *mod, char *buffer)
{
846
	return sprintf(buffer, "%u\n", module_refcount(mod));
Linus Torvalds's avatar
Linus Torvalds committed
847 848 849
}

static struct module_attribute refcnt = {
850
	.attr = { .name = "refcnt", .mode = 0444 },
Linus Torvalds's avatar
Linus Torvalds committed
851 852 853
	.show = show_refcnt,
};

Al Viro's avatar
Al Viro committed
854 855 856
void module_put(struct module *module)
{
	if (module) {
857
		preempt_disable();
858 859
		smp_wmb(); /* see comment in module_refcount */
		__this_cpu_inc(module->refptr->decs);
860

861
		trace_module_put(module, _RET_IP_);
Al Viro's avatar
Al Viro committed
862 863 864
		/* Maybe they're waiting for us to drop reference? */
		if (unlikely(!module_is_live(module)))
			wake_up_process(module->waiter);
865
		preempt_enable();
Al Viro's avatar
Al Viro committed
866 867 868 869
	}
}
EXPORT_SYMBOL(module_put);

Linus Torvalds's avatar
Linus Torvalds committed
870
#else /* !CONFIG_MODULE_UNLOAD */
871
static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
872 873 874 875 876 877 878 879 880
{
	/* We don't know the usage count, or what modules are using. */
	seq_printf(m, " - -");
}

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

881
int use_module(struct module *a, struct module *b)
Linus Torvalds's avatar
Linus Torvalds committed
882
{
883
	return strong_try_module_get(b) == 0;
Linus Torvalds's avatar
Linus Torvalds committed
884
}
885
EXPORT_SYMBOL_GPL(use_module);
Linus Torvalds's avatar
Linus Torvalds committed
886 887 888 889 890 891

static inline void module_unload_init(struct module *mod)
{
}
#endif /* CONFIG_MODULE_UNLOAD */

892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911
static ssize_t show_initstate(struct module_attribute *mattr,
			   struct module *mod, char *buffer)
{
	const char *state = "unknown";

	switch (mod->state) {
	case MODULE_STATE_LIVE:
		state = "live";
		break;
	case MODULE_STATE_COMING:
		state = "coming";
		break;
	case MODULE_STATE_GOING:
		state = "going";
		break;
	}
	return sprintf(buffer, "%s\n", state);
}

static struct module_attribute initstate = {
912
	.attr = { .name = "initstate", .mode = 0444 },
913 914 915
	.show = show_initstate,
};

916 917 918
static struct module_attribute *modinfo_attrs[] = {
	&modinfo_version,
	&modinfo_srcversion,
919
	&initstate,
920 921 922 923 924 925
#ifdef CONFIG_MODULE_UNLOAD
	&refcnt,
#endif
	NULL,
};

Linus Torvalds's avatar
Linus Torvalds committed
926 927
static const char vermagic[] = VERMAGIC_STRING;

928
static int try_to_force_load(struct module *mod, const char *reason)
929 930
{
#ifdef CONFIG_MODULE_FORCE_LOAD
Andi Kleen's avatar
Andi Kleen committed
931
	if (!test_taint(TAINT_FORCED_MODULE))
932 933
		printk(KERN_WARNING "%s: %s: kernel tainted.\n",
		       mod->name, reason);
934 935 936 937 938 939 940
	add_taint_module(mod, TAINT_FORCED_MODULE);
	return 0;
#else
	return -ENOEXEC;
#endif
}

Linus Torvalds's avatar
Linus Torvalds committed
941
#ifdef CONFIG_MODVERSIONS
942 943 944 945 946 947 948 949 950 951 952
/* 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
953 954 955 956
static int check_version(Elf_Shdr *sechdrs,
			 unsigned int versindex,
			 const char *symname,
			 struct module *mod, 
957 958
			 const unsigned long *crc,
			 const struct module *crc_owner)
Linus Torvalds's avatar
Linus Torvalds committed
959 960 961 962 963 964 965 966
{
	unsigned int i, num_versions;
	struct modversion_info *versions;

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

967 968 969 970
	/* 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
971 972 973 974 975 976 977 978
	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;

979
		if (versions[i].crc == maybe_relocated(*crc, crc_owner))
Linus Torvalds's avatar
Linus Torvalds committed
980 981
			return 1;
		DEBUGP("Found checksum %lX vs module %lX\n",
982
		       maybe_relocated(*crc, crc_owner), versions[i].crc);
983
		goto bad_version;
Linus Torvalds's avatar
Linus Torvalds committed
984
	}
985

986 987 988
	printk(KERN_WARNING "%s: no symbol version for %s\n",
	       mod->name, symname);
	return 0;
989 990 991 992 993

bad_version:
	printk("%s: disagrees about version of symbol %s\n",
	       mod->name, symname);
	return 0;
Linus Torvalds's avatar
Linus Torvalds committed
994 995 996 997 998 999 1000 1001
}

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

1002 1003
	if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
			 &crc, true, false))
Linus Torvalds's avatar
Linus Torvalds committed
1004
		BUG();
1005 1006
	return check_version(sechdrs, versindex, "module_layout", mod, crc,
			     NULL);
Linus Torvalds's avatar
Linus Torvalds committed
1007 1008
}

1009 1010 1011
/* 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
1012
{
1013 1014 1015 1016
	if (has_crcs) {
		amagic += strcspn(amagic, " ");
		bmagic += strcspn(bmagic, " ");
	}
Linus Torvalds's avatar
Linus Torvalds committed
1017 1018 1019 1020 1021 1022 1023
	return strcmp(amagic, bmagic) == 0;
}
#else
static inline int check_version(Elf_Shdr *sechdrs,
				unsigned int versindex,
				const char *symname,
				struct module *mod, 
1024 1025
				const unsigned long *crc,
				const struct module *crc_owner)
Linus Torvalds's avatar
Linus Torvalds committed
1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036
{
	return 1;
}

static inline int check_modstruct_version(Elf_Shdr *sechdrs,
					  unsigned int versindex,
					  struct module *mod)
{
	return 1;
}

1037 1038
static inline int same_magic(const char *amagic, const char *bmagic,
			     bool has_crcs)
Linus Torvalds's avatar
Linus Torvalds committed
1039 1040 1041 1042 1043 1044 1045
{
	return strcmp(amagic, bmagic) == 0;
}
#endif /* CONFIG_MODVERSIONS */

/* Resolve a symbol for this module.  I.e. if we find one, record usage.
   Must be holding module_mutex. */
1046 1047 1048 1049
static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
						  unsigned int versindex,
						  const char *name,
						  struct module *mod)
Linus Torvalds's avatar
Linus Torvalds committed
1050 1051
{
	struct module *owner;
1052
	const struct kernel_symbol *sym;
Linus Torvalds's avatar
Linus Torvalds committed
1053 1054
	const unsigned long *crc;

1055
	sym = find_symbol(name, &owner, &crc,
Andi Kleen's avatar
Andi Kleen committed
1056
			  !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1057 1058 1059
	/* use_module can fail due to OOM,
	   or module initialization or unloading */
	if (sym) {
1060 1061
		if (!check_version(sechdrs, versindex, name, mod, crc, owner)
		    || !use_module(mod, owner))
1062
			sym = NULL;
Linus Torvalds's avatar
Linus Torvalds committed
1063
	}
1064
	return sym;
Linus Torvalds's avatar
Linus Torvalds committed
1065 1066 1067 1068 1069 1070
}

/*
 * /sys/module/foo/sections stuff
 * J. Corbet <corbet@lwn.net>
 */
1071
#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1072 1073 1074 1075 1076 1077

static inline bool sect_empty(const Elf_Shdr *sect)
{
	return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
}

1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091
struct module_sect_attr
{
	struct module_attribute mattr;
	char *name;
	unsigned long address;
};

struct module_sect_attrs
{
	struct attribute_group grp;
	unsigned int nsections;
	struct module_sect_attr attrs[0];
};

Linus Torvalds's avatar
Linus Torvalds committed
1092 1093 1094 1095 1096 1097 1098 1099
static ssize_t module_sect_show(struct module_attribute *mattr,
				struct module *mod, char *buf)
{
	struct module_sect_attr *sattr =
		container_of(mattr, struct module_sect_attr, mattr);
	return sprintf(buf, "0x%lx\n", sattr->address);
}

1100 1101
static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
{
1102
	unsigned int section;
1103 1104 1105 1106 1107 1108

	for (section = 0; section < sect_attrs->nsections; section++)
		kfree(sect_attrs->attrs[section].name);
	kfree(sect_attrs);
}

Linus Torvalds's avatar
Linus Torvalds committed
1109 1110 1111 1112 1113 1114 1115
static void add_sect_attrs(struct module *mod, unsigned int nsect,
		char *secstrings, Elf_Shdr *sechdrs)
{
	unsigned int nloaded = 0, i, size[2];
	struct module_sect_attrs *sect_attrs;
	struct module_sect_attr *sattr;
	struct attribute **gattr;
1116

Linus Torvalds's avatar
Linus Torvalds committed
1117 1118
	/* Count loaded sections and allocate structures */
	for (i = 0; i < nsect; i++)
1119
		if (!sect_empty(&sechdrs[i]))
Linus Torvalds's avatar
Linus Torvalds committed
1120 1121 1122 1123 1124
			nloaded++;
	size[0] = ALIGN(sizeof(*sect_attrs)
			+ nloaded * sizeof(sect_attrs->attrs[0]),
			sizeof(sect_attrs->grp.attrs[0]));
	size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1125 1126
	sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
	if (sect_attrs == NULL)
Linus Torvalds's avatar
Linus Torvalds committed
1127 1128 1129 1130 1131 1132
		return;

	/* Setup section attributes. */
	sect_attrs->grp.name = "sections";
	sect_attrs->grp.attrs = (void *)sect_attrs + size[0];

1133
	sect_attrs->nsections = 0;
Linus Torvalds's avatar
Linus Torvalds committed
1134 1135 1136
	sattr = &sect_attrs->attrs[0];
	gattr = &sect_attrs->grp.attrs[0];
	for (i = 0; i < nsect; i++) {
1137
		if (sect_empty(&sechdrs[i]))
1138
			continue;
Linus Torvalds's avatar
Linus Torvalds committed
1139
		sattr->address = sechdrs[i].sh_addr;
1140 1141 1142 1143 1144
		sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
					GFP_KERNEL);
		if (sattr->name == NULL)
			goto out;
		sect_attrs->nsections++;
1145
		sysfs_attr_init(&sattr->mattr.attr);
Linus Torvalds's avatar
Linus Torvalds committed
1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159
		sattr->mattr.show = module_sect_show;
		sattr->mattr.store = NULL;
		sattr->mattr.attr.name = sattr->name;
		sattr->mattr.attr.mode = S_IRUGO;
		*(gattr++) = &(sattr++)->mattr.attr;
	}
	*gattr = NULL;

	if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
		goto out;

	mod->sect_attrs = sect_attrs;
	return;
  out:
1160
	free_sect_attrs(sect_attrs);
Linus Torvalds's avatar
Linus Torvalds committed
1161 1162 1163 1164 1165 1166 1167 1168 1169
}

static void remove_sect_attrs(struct module *mod)
{
	if (mod->sect_attrs) {
		sysfs_remove_group(&mod->mkobj.kobj,
				   &mod->sect_attrs->grp);
		/* We are positive that no one is using any sect attrs
		 * at this point.  Deallocate immediately. */
1170
		free_sect_attrs(mod->sect_attrs);
Linus Torvalds's avatar
Linus Torvalds committed
1171 1172 1173 1174
		mod->sect_attrs = NULL;
	}
}

Roland McGrath's avatar
Roland McGrath committed
1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202
/*
 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
 */

struct module_notes_attrs {
	struct kobject *dir;
	unsigned int notes;
	struct bin_attribute attrs[0];
};

static ssize_t module_notes_read(struct kobject *kobj,
				 struct bin_attribute *bin_attr,
				 char *buf, loff_t pos, size_t count)
{
	/*
	 * The caller checked the pos and count against our size.
	 */
	memcpy(buf, bin_attr->private + pos, count);
	return count;
}

static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
			     unsigned int i)
{
	if (notes_attrs->dir) {
		while (i-- > 0)
			sysfs_remove_bin_file(notes_attrs->dir,
					      &notes_attrs->attrs[i]);
1203
		kobject_put(notes_attrs->dir);
Roland McGrath's avatar
Roland McGrath committed
1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214
	}
	kfree(notes_attrs);
}

static void add_notes_attrs(struct module *mod, unsigned int nsect,
			    char *secstrings, Elf_Shdr *sechdrs)
{
	unsigned int notes, loaded, i;
	struct module_notes_attrs *notes_attrs;
	struct bin_attribute *nattr;

1215 1216 1217 1218
	/* failed to create section attributes, so can't create notes */
	if (!mod->sect_attrs)
		return;

Roland McGrath's avatar
Roland McGrath committed
1219 1220 1221
	/* Count notes sections and allocate structures.  */
	notes = 0;
	for (i = 0; i < nsect; i++)
1222
		if (!sect_empty(&sechdrs[i]) &&
Roland McGrath's avatar
Roland McGrath committed
1223 1224 1225 1226 1227 1228 1229