module.c 67.8 KB
Newer Older
1
/*
L
Linus Torvalds 已提交
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
   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>
#include <linux/init.h>
22
#include <linux/kallsyms.h>
R
Roland McGrath 已提交
23
#include <linux/sysfs.h>
24
#include <linux/kernel.h>
L
Linus Torvalds 已提交
25 26 27 28 29 30 31
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/elf.h>
#include <linux/seq_file.h>
#include <linux/syscalls.h>
#include <linux/fcntl.h>
#include <linux/rcupdate.h>
32
#include <linux/capability.h>
L
Linus Torvalds 已提交
33 34 35 36 37 38
#include <linux/cpu.h>
#include <linux/moduleparam.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/vermagic.h>
#include <linux/notifier.h>
A
Al Viro 已提交
39
#include <linux/sched.h>
L
Linus Torvalds 已提交
40 41
#include <linux/stop_machine.h>
#include <linux/device.h>
42
#include <linux/string.h>
A
Arjan van de Ven 已提交
43
#include <linux/mutex.h>
44
#include <linux/unwind.h>
L
Linus Torvalds 已提交
45 46
#include <asm/uaccess.h>
#include <asm/cacheflush.h>
47
#include <linux/license.h>
48
#include <asm/sections.h>
L
Linus Torvalds 已提交
49 50 51 52 53 54 55 56 57 58 59 60 61 62

#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))

R
Rusty Russell 已提交
63 64
/* List of modules, protected by module_mutex or preempt_disable
 * (add/delete uses stop_machine). */
65
static DEFINE_MUTEX(module_mutex);
L
Linus Torvalds 已提交
66 67
static LIST_HEAD(modules);

68 69 70
/* Waiting for a module to finish initializing? */
static DECLARE_WAIT_QUEUE_HEAD(module_wq);

71
static BLOCKING_NOTIFIER_HEAD(module_notify_list);
L
Linus Torvalds 已提交
72 73 74

int register_module_notifier(struct notifier_block * nb)
{
75
	return blocking_notifier_chain_register(&module_notify_list, nb);
L
Linus Torvalds 已提交
76 77 78 79 80
}
EXPORT_SYMBOL(register_module_notifier);

int unregister_module_notifier(struct notifier_block * nb)
{
81
	return blocking_notifier_chain_unregister(&module_notify_list, nb);
L
Linus Torvalds 已提交
82 83 84
}
EXPORT_SYMBOL(unregister_module_notifier);

85 86
/* We require a truly strong try_module_get(): 0 means failure due to
   ongoing or failed initialization etc. */
L
Linus Torvalds 已提交
87 88 89
static inline int strong_try_module_get(struct module *mod)
{
	if (mod && mod->state == MODULE_STATE_COMING)
90 91
		return -EBUSY;
	if (try_module_get(mod))
L
Linus Torvalds 已提交
92
		return 0;
93 94
	else
		return -ENOENT;
L
Linus Torvalds 已提交
95 96
}

97 98 99 100 101 102
static inline void add_taint_module(struct module *mod, unsigned flag)
{
	add_taint(flag);
	mod->taints |= flag;
}

103 104 105
/*
 * 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.
L
Linus Torvalds 已提交
106 107 108 109 110 111 112
 */
void __module_put_and_exit(struct module *mod, long code)
{
	module_put(mod);
	do_exit(code);
}
EXPORT_SYMBOL(__module_put_and_exit);
D
Daniel Walker 已提交
113

L
Linus Torvalds 已提交
114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134
/* 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;
}

/* 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[];
135 136
extern const struct kernel_symbol __start___ksymtab_gpl_future[];
extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
137 138 139 140 141 142
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[];
extern const struct kernel_symbol __start___ksymtab_gpl_future[];
extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
L
Linus Torvalds 已提交
143 144
extern const unsigned long __start___kcrctab[];
extern const unsigned long __start___kcrctab_gpl[];
145
extern const unsigned long __start___kcrctab_gpl_future[];
146 147
extern const unsigned long __start___kcrctab_unused[];
extern const unsigned long __start___kcrctab_unused_gpl[];
L
Linus Torvalds 已提交
148 149 150 151

#ifndef CONFIG_MODVERSIONS
#define symversion(base, idx) NULL
#else
A
Andrew Morton 已提交
152
#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
L
Linus Torvalds 已提交
153 154
#endif

155 156 157 158 159 160 161 162 163 164 165 166
/* lookup symbol in given range of kernel_symbols */
static const struct kernel_symbol *lookup_symbol(const char *name,
	const struct kernel_symbol *start,
	const struct kernel_symbol *stop)
{
	const struct kernel_symbol *ks = start;
	for (; ks < stop; ks++)
		if (strcmp(ks->name, name) == 0)
			return ks;
	return NULL;
}

167
static bool always_ok(bool gplok, bool warn, const char *name)
168
{
169
	return true;
170 171
}

172
static bool printk_unused_warning(bool gplok, bool warn, const char *name)
L
Linus Torvalds 已提交
173
{
174 175 176 177 178 179 180 181 182 183
	if (warn) {
		printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
		       "however this module is using it.\n", 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");
L
Linus Torvalds 已提交
184
	}
185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208
	return true;
}

static bool gpl_only_unused_warning(bool gplok, bool warn, const char *name)
{
	if (!gplok)
		return false;
	return printk_unused_warning(gplok, warn, name);
}

static bool gpl_only(bool gplok, bool warn, const char *name)
{
	return gplok;
}

static bool warn_if_not_gpl(bool gplok, bool warn, const char *name)
{
	if (!gplok && warn) {
		printk(KERN_WARNING "Symbol %s is being used "
		       "by a non-GPL module, which will not "
		       "be allowed in the future\n", name);
		printk(KERN_WARNING "Please see the file "
		       "Documentation/feature-removal-schedule.txt "
		       "in the kernel source tree for more details.\n");
209
	}
210 211
	return true;
}
L
Linus Torvalds 已提交
212

213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238
struct symsearch {
	const struct kernel_symbol *start, *stop;
	const unsigned long *crcs;
	bool (*check)(bool gplok, bool warn, const char *name);
};

/* Look through this array of symbol tables for a symbol match which
 * passes the check function. */
static const struct kernel_symbol *search_symarrays(const struct symsearch *arr,
						    unsigned int num,
						    const char *name,
						    bool gplok,
						    bool warn,
						    const unsigned long **crc)
{
	unsigned int i;
	const struct kernel_symbol *ks;

	for (i = 0; i < num; i++) {
		ks = lookup_symbol(name, arr[i].start, arr[i].stop);
		if (!ks || !arr[i].check(gplok, warn, name))
			continue;

		if (crc)
			*crc = symversion(arr[i].crcs, ks - arr[i].start);
		return ks;
239
	}
240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264
	return NULL;
}

/* Find a symbol, return value, (optional) crc and (optional) module
 * which owns it */
static unsigned long find_symbol(const char *name,
				 struct module **owner,
				 const unsigned long **crc,
				 bool gplok,
				 bool warn)
{
	struct module *mod;
	const struct kernel_symbol *ks;
	const struct symsearch arr[] = {
		{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
		  always_ok },
		{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
		  __start___kcrctab_gpl, gpl_only },
		{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
		  __start___kcrctab_gpl_future, warn_if_not_gpl },
		{ __start___ksymtab_unused, __stop___ksymtab_unused,
		  __start___kcrctab_unused, printk_unused_warning },
		{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
		  __start___kcrctab_unused_gpl, gpl_only_unused_warning },
	};
265

266 267
	/* Core kernel first. */
	ks = search_symarrays(arr, ARRAY_SIZE(arr), name, gplok, warn, crc);
268
	if (ks) {
269 270
		if (owner)
			*owner = NULL;
271 272 273
		return ks->value;
	}

D
Daniel Walker 已提交
274
	/* Now try modules. */
L
Linus Torvalds 已提交
275
	list_for_each_entry(mod, &modules, list) {
276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293
		struct symsearch arr[] = {
			{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
			  always_ok },
			{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
			  mod->gpl_crcs, gpl_only },
			{ mod->gpl_future_syms,
			  mod->gpl_future_syms + mod->num_gpl_future_syms,
			  mod->gpl_future_crcs, warn_if_not_gpl },
			{ mod->unused_syms,
			  mod->unused_syms + mod->num_unused_syms,
			  mod->unused_crcs, printk_unused_warning },
			{ mod->unused_gpl_syms,
			  mod->unused_gpl_syms + mod->num_unused_gpl_syms,
			  mod->unused_gpl_crcs, gpl_only_unused_warning },
		};

		ks = search_symarrays(arr, ARRAY_SIZE(arr),
				      name, gplok, warn, crc);
294
		if (ks) {
295 296
			if (owner)
				*owner = mod;
297 298
			return ks->value;
		}
L
Linus Torvalds 已提交
299
	}
300

L
Linus Torvalds 已提交
301
	DEBUGP("Failed to find symbol %s\n", name);
302
	return -ENOENT;
L
Linus Torvalds 已提交
303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326
}

/* Search for module by name: must hold module_mutex. */
static struct module *find_module(const char *name)
{
	struct module *mod;

	list_for_each_entry(mod, &modules, list) {
		if (strcmp(mod->name, name) == 0)
			return mod;
	}
	return NULL;
}

#ifdef CONFIG_SMP
/* Number of blocks used and allocated. */
static unsigned int pcpu_num_used, pcpu_num_allocated;
/* Size of each block.  -ve means used. */
static int *pcpu_size;

static int split_block(unsigned int i, unsigned short size)
{
	/* Reallocation required? */
	if (pcpu_num_used + 1 > pcpu_num_allocated) {
P
Pekka Enberg 已提交
327 328 329 330
		int *new;

		new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2,
			       GFP_KERNEL);
L
Linus Torvalds 已提交
331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354
		if (!new)
			return 0;

		pcpu_num_allocated *= 2;
		pcpu_size = new;
	}

	/* Insert a new subblock */
	memmove(&pcpu_size[i+1], &pcpu_size[i],
		sizeof(pcpu_size[0]) * (pcpu_num_used - i));
	pcpu_num_used++;

	pcpu_size[i+1] -= size;
	pcpu_size[i] = size;
	return 1;
}

static inline unsigned int block_size(int val)
{
	if (val < 0)
		return -val;
	return val;
}

355 356
static void *percpu_modalloc(unsigned long size, unsigned long align,
			     const char *name)
L
Linus Torvalds 已提交
357 358 359 360 361
{
	unsigned long extra;
	unsigned int i;
	void *ptr;

362 363 364 365
	if (align > PAGE_SIZE) {
		printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
		       name, align, PAGE_SIZE);
		align = PAGE_SIZE;
366
	}
L
Linus Torvalds 已提交
367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438

	ptr = __per_cpu_start;
	for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
		/* Extra for alignment requirement. */
		extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
		BUG_ON(i == 0 && extra != 0);

		if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
			continue;

		/* Transfer extra to previous block. */
		if (pcpu_size[i-1] < 0)
			pcpu_size[i-1] -= extra;
		else
			pcpu_size[i-1] += extra;
		pcpu_size[i] -= extra;
		ptr += extra;

		/* Split block if warranted */
		if (pcpu_size[i] - size > sizeof(unsigned long))
			if (!split_block(i, size))
				return NULL;

		/* Mark allocated */
		pcpu_size[i] = -pcpu_size[i];
		return ptr;
	}

	printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
	       size);
	return NULL;
}

static void percpu_modfree(void *freeme)
{
	unsigned int i;
	void *ptr = __per_cpu_start + block_size(pcpu_size[0]);

	/* First entry is core kernel percpu data. */
	for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
		if (ptr == freeme) {
			pcpu_size[i] = -pcpu_size[i];
			goto free;
		}
	}
	BUG();

 free:
	/* Merge with previous? */
	if (pcpu_size[i-1] >= 0) {
		pcpu_size[i-1] += pcpu_size[i];
		pcpu_num_used--;
		memmove(&pcpu_size[i], &pcpu_size[i+1],
			(pcpu_num_used - i) * sizeof(pcpu_size[0]));
		i--;
	}
	/* Merge with next? */
	if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
		pcpu_size[i] += pcpu_size[i+1];
		pcpu_num_used--;
		memmove(&pcpu_size[i+1], &pcpu_size[i+2],
			(pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
	}
}

static unsigned int find_pcpusec(Elf_Ehdr *hdr,
				 Elf_Shdr *sechdrs,
				 const char *secstrings)
{
	return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
}

439 440 441 442 443 444 445 446
static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size)
{
	int cpu;

	for_each_possible_cpu(cpu)
		memcpy(pcpudest + per_cpu_offset(cpu), from, size);
}

L
Linus Torvalds 已提交
447 448 449 450 451 452 453
static int percpu_modinit(void)
{
	pcpu_num_used = 2;
	pcpu_num_allocated = 2;
	pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
			    GFP_KERNEL);
	/* Static in-kernel percpu data (used). */
454
	pcpu_size[0] = -(__per_cpu_end-__per_cpu_start);
L
Linus Torvalds 已提交
455 456 457 458 459 460 461 462
	/* Free room. */
	pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
	if (pcpu_size[1] < 0) {
		printk(KERN_ERR "No per-cpu room for modules.\n");
		pcpu_num_used = 1;
	}

	return 0;
D
Daniel Walker 已提交
463
}
L
Linus Torvalds 已提交
464 465
__initcall(percpu_modinit);
#else /* ... !CONFIG_SMP */
466 467
static inline void *percpu_modalloc(unsigned long size, unsigned long align,
				    const char *name)
L
Linus Torvalds 已提交
468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488
{
	return NULL;
}
static inline void percpu_modfree(void *pcpuptr)
{
	BUG();
}
static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
					Elf_Shdr *sechdrs,
					const char *secstrings)
{
	return 0;
}
static inline void percpu_modcopy(void *pcpudst, const void *src,
				  unsigned long size)
{
	/* pcpusec should be 0, and size of that section should be 0. */
	BUG_ON(size != 0);
}
#endif /* CONFIG_SMP */

489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504
#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)                  \
{                                                                     \
D
Daniel Walker 已提交
505 506
	kfree(mod->field);                                            \
	mod->field = NULL;                                            \
507 508
}                                                                     \
static struct module_attribute modinfo_##field = {                    \
509
	.attr = { .name = __stringify(field), .mode = 0444 },         \
510 511 512 513 514 515 516 517 518
	.show = show_modinfo_##field,                                 \
	.setup = setup_modinfo_##field,                               \
	.test = modinfo_##field##_exists,                             \
	.free = free_modinfo_##field,                                 \
};

MODINFO_ATTR(version);
MODINFO_ATTR(srcversion);

519 520
static char last_unloaded_module[MODULE_NAME_LEN+1];

521
#ifdef CONFIG_MODULE_UNLOAD
L
Linus Torvalds 已提交
522 523 524 525 526 527 528 529 530
/* Init the unload section of the module. */
static void module_unload_init(struct module *mod)
{
	unsigned int i;

	INIT_LIST_HEAD(&mod->modules_which_use_me);
	for (i = 0; i < NR_CPUS; i++)
		local_set(&mod->ref[i].count, 0);
	/* Hold reference count during initialization. */
I
Ingo Molnar 已提交
531
	local_set(&mod->ref[raw_smp_processor_id()].count, 1);
L
Linus Torvalds 已提交
532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561
	/* 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 */
static int use_module(struct module *a, struct module *b)
{
	struct module_use *use;
562
	int no_warn, err;
K
Kay Sievers 已提交
563

L
Linus Torvalds 已提交
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)
L
Linus Torvalds 已提交
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);
K
Kay Sievers 已提交
589
	no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
L
Linus Torvalds 已提交
590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606
	return 1;
}

/* 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);
K
Kay Sievers 已提交
607
				sysfs_remove_link(i->holders_dir, mod->name);
L
Linus Torvalds 已提交
608 609 610 611 612 613 614 615
				/* There can be at most one match. */
				break;
			}
		}
	}
}

#ifdef CONFIG_MODULE_FORCE_UNLOAD
616
static inline int try_force_unload(unsigned int flags)
L
Linus Torvalds 已提交
617 618 619
{
	int ret = (flags & O_TRUNC);
	if (ret)
620
		add_taint(TAINT_FORCED_RMMOD);
L
Linus Torvalds 已提交
621 622 623
	return ret;
}
#else
624
static inline int try_force_unload(unsigned int flags)
L
Linus Torvalds 已提交
625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643
{
	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;

	/* If it's not unused, quit unless we are told to block. */
	if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
644
		if (!(*sref->forced = try_force_unload(sref->flags)))
L
Linus Torvalds 已提交
645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674
			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)
{
	struct stopref sref = { mod, flags, forced };

	return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
}

unsigned int module_refcount(struct module *mod)
{
	unsigned int i, total = 0;

	for (i = 0; i < NR_CPUS; i++)
		total += local_read(&mod->ref[i].count);
	return total;
}
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)
{
675
	/* Since we might sleep for some time, release the mutex first */
676
	mutex_unlock(&module_mutex);
L
Linus Torvalds 已提交
677 678 679 680 681 682 683 684
	for (;;) {
		DEBUGP("Looking at refcount...\n");
		set_current_state(TASK_UNINTERRUPTIBLE);
		if (module_refcount(mod) == 0)
			break;
		schedule();
	}
	current->state = TASK_RUNNING;
685
	mutex_lock(&module_mutex);
L
Linus Torvalds 已提交
686 687
}

688 689
asmlinkage long
sys_delete_module(const char __user *name_user, unsigned int flags)
L
Linus Torvalds 已提交
690 691
{
	struct module *mod;
692
	char name[MODULE_NAME_LEN];
L
Linus Torvalds 已提交
693 694
	int ret, forced = 0;

695 696 697 698 699 700 701
	if (!capable(CAP_SYS_MODULE))
		return -EPERM;

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

702
	if (mutex_lock_interruptible(&module_mutex) != 0)
L
Linus Torvalds 已提交
703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726
		return -EINTR;

	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 */
R
Rusty Russell 已提交
727
	if (mod->init && !mod->exit) {
728
		forced = try_force_unload(flags);
L
Linus Torvalds 已提交
729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747
		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);

748
	mutex_unlock(&module_mutex);
L
Linus Torvalds 已提交
749
	/* Final destruction now noone is using it. */
750
	if (mod->exit != NULL)
L
Linus Torvalds 已提交
751
		mod->exit();
752 753 754
	blocking_notifier_call_chain(&module_notify_list,
				     MODULE_STATE_GOING, mod);
	mutex_lock(&module_mutex);
755
	/* Store the name of the last unloaded module for diagnostic purposes */
756
	strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
L
Linus Torvalds 已提交
757 758 759
	free_module(mod);

 out:
760
	mutex_unlock(&module_mutex);
L
Linus Torvalds 已提交
761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790
	return ret;
}

static void print_unload_info(struct seq_file *m, struct module *mod)
{
	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;

R
Rusty Russell 已提交
791
	preempt_disable();
792
	if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false)))
L
Linus Torvalds 已提交
793 794
		BUG();
	module_put(owner);
R
Rusty Russell 已提交
795
	preempt_enable();
L
Linus Torvalds 已提交
796 797 798 799 800
}
EXPORT_SYMBOL(__symbol_put);

void symbol_put_addr(void *addr)
{
801
	struct module *modaddr;
L
Linus Torvalds 已提交
802

803 804
	if (core_kernel_text((unsigned long)addr))
		return;
L
Linus Torvalds 已提交
805

806 807 808
	if (!(modaddr = module_text_address((unsigned long)addr)))
		BUG();
	module_put(modaddr);
L
Linus Torvalds 已提交
809 810 811 812 813 814
}
EXPORT_SYMBOL_GPL(symbol_put_addr);

static ssize_t show_refcnt(struct module_attribute *mattr,
			   struct module *mod, char *buffer)
{
815
	return sprintf(buffer, "%u\n", module_refcount(mod));
L
Linus Torvalds 已提交
816 817 818
}

static struct module_attribute refcnt = {
819
	.attr = { .name = "refcnt", .mode = 0444 },
L
Linus Torvalds 已提交
820 821 822
	.show = show_refcnt,
};

A
Al Viro 已提交
823 824 825 826 827 828 829 830 831 832 833 834 835
void module_put(struct module *module)
{
	if (module) {
		unsigned int cpu = get_cpu();
		local_dec(&module->ref[cpu].count);
		/* Maybe they're waiting for us to drop reference? */
		if (unlikely(!module_is_live(module)))
			wake_up_process(module->waiter);
		put_cpu();
	}
}
EXPORT_SYMBOL(module_put);

L
Linus Torvalds 已提交
836 837 838 839 840 841 842 843 844 845 846 847 848
#else /* !CONFIG_MODULE_UNLOAD */
static void print_unload_info(struct seq_file *m, struct module *mod)
{
	/* We don't know the usage count, or what modules are using. */
	seq_printf(m, " - -");
}

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

static inline int use_module(struct module *a, struct module *b)
{
849
	return strong_try_module_get(b) == 0;
L
Linus Torvalds 已提交
850 851 852 853 854 855 856
}

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

857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876
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 = {
877
	.attr = { .name = "initstate", .mode = 0444 },
878 879 880
	.show = show_initstate,
};

881 882 883
static struct module_attribute *modinfo_attrs[] = {
	&modinfo_version,
	&modinfo_srcversion,
884
	&initstate,
885 886 887 888 889 890
#ifdef CONFIG_MODULE_UNLOAD
	&refcnt,
#endif
	NULL,
};

L
Linus Torvalds 已提交
891 892
static const char vermagic[] = VERMAGIC_STRING;

893 894 895 896 897 898 899 900 901 902 903 904 905
static int try_to_force_load(struct module *mod, const char *symname)
{
#ifdef CONFIG_MODULE_FORCE_LOAD
	if (!(tainted & TAINT_FORCED_MODULE))
		printk("%s: no version for \"%s\" found: kernel tainted.\n",
		       mod->name, symname);
	add_taint_module(mod, TAINT_FORCED_MODULE);
	return 0;
#else
	return -ENOEXEC;
#endif
}

L
Linus Torvalds 已提交
906 907 908 909 910 911 912 913 914 915 916 917 918 919
#ifdef CONFIG_MODVERSIONS
static int check_version(Elf_Shdr *sechdrs,
			 unsigned int versindex,
			 const char *symname,
			 struct module *mod, 
			 const unsigned long *crc)
{
	unsigned int i, num_versions;
	struct modversion_info *versions;

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

920 921 922 923
	/* No versions at all?  modprobe --force does this. */
	if (versindex == 0)
		return try_to_force_load(mod, symname) == 0;

L
Linus Torvalds 已提交
924 925 926 927 928 929 930 931 932 933 934 935
	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;

		if (versions[i].crc == *crc)
			return 1;
		DEBUGP("Found checksum %lX vs module %lX\n",
		       *crc, versions[i].crc);
936
		goto bad_version;
L
Linus Torvalds 已提交
937
	}
938

939 940 941
	printk(KERN_WARNING "%s: no symbol version for %s\n",
	       mod->name, symname);
	return 0;
942 943 944 945 946

bad_version:
	printk("%s: disagrees about version of symbol %s\n",
	       mod->name, symname);
	return 0;
L
Linus Torvalds 已提交
947 948 949 950 951 952 953 954
}

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

955
	if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false)))
L
Linus Torvalds 已提交
956
		BUG();
957
	return check_version(sechdrs, versindex, "struct_module", mod, crc);
L
Linus Torvalds 已提交
958 959
}

960 961 962
/* 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)
L
Linus Torvalds 已提交
963
{
964 965 966 967
	if (has_crcs) {
		amagic += strcspn(amagic, " ");
		bmagic += strcspn(bmagic, " ");
	}
L
Linus Torvalds 已提交
968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986
	return strcmp(amagic, bmagic) == 0;
}
#else
static inline int check_version(Elf_Shdr *sechdrs,
				unsigned int versindex,
				const char *symname,
				struct module *mod, 
				const unsigned long *crc)
{
	return 1;
}

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

987 988
static inline int same_magic(const char *amagic, const char *bmagic,
			     bool has_crcs)
L
Linus Torvalds 已提交
989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004
{
	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. */
static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
				    unsigned int versindex,
				    const char *name,
				    struct module *mod)
{
	struct module *owner;
	unsigned long ret;
	const unsigned long *crc;

1005 1006
	ret = find_symbol(name, &owner, &crc,
			  !(mod->taints & TAINT_PROPRIETARY_MODULE), true);
1007
	if (!IS_ERR_VALUE(ret)) {
1008 1009
		/* use_module can fail due to OOM,
		   or module initialization or unloading */
L
Linus Torvalds 已提交
1010 1011
		if (!check_version(sechdrs, versindex, name, mod, crc) ||
		    !use_module(mod, owner))
1012
			ret = -EINVAL;
L
Linus Torvalds 已提交
1013 1014 1015 1016 1017 1018 1019 1020
	}
	return ret;
}

/*
 * /sys/module/foo/sections stuff
 * J. Corbet <corbet@lwn.net>
 */
1021
#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035
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];
};

L
Linus Torvalds 已提交
1036 1037 1038 1039 1040 1041 1042 1043
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);
}

1044 1045
static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
{
1046
	unsigned int section;
1047 1048 1049 1050 1051 1052

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

L
Linus Torvalds 已提交
1053 1054 1055 1056 1057 1058 1059
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;
D
Daniel Walker 已提交
1060

L
Linus Torvalds 已提交
1061 1062 1063 1064 1065 1066 1067 1068
	/* Count loaded sections and allocate structures */
	for (i = 0; i < nsect; i++)
		if (sechdrs[i].sh_flags & SHF_ALLOC)
			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]);
1069 1070
	sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
	if (sect_attrs == NULL)
L
Linus Torvalds 已提交
1071 1072 1073 1074 1075 1076
		return;

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

1077
	sect_attrs->nsections = 0;
L
Linus Torvalds 已提交
1078 1079 1080 1081 1082 1083
	sattr = &sect_attrs->attrs[0];
	gattr = &sect_attrs->grp.attrs[0];
	for (i = 0; i < nsect; i++) {
		if (! (sechdrs[i].sh_flags & SHF_ALLOC))
			continue;
		sattr->address = sechdrs[i].sh_addr;
1084 1085 1086 1087 1088
		sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
					GFP_KERNEL);
		if (sattr->name == NULL)
			goto out;
		sect_attrs->nsections++;
L
Linus Torvalds 已提交
1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102
		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:
1103
	free_sect_attrs(sect_attrs);
L
Linus Torvalds 已提交
1104 1105 1106 1107 1108 1109 1110 1111 1112
}

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. */
1113
		free_sect_attrs(mod->sect_attrs);
L
Linus Torvalds 已提交
1114 1115 1116 1117
		mod->sect_attrs = NULL;
	}
}

R
Roland McGrath 已提交
1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189
/*
 * /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]);
		kobject_del(notes_attrs->dir);
	}
	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;

	/* Count notes sections and allocate structures.  */
	notes = 0;
	for (i = 0; i < nsect; i++)
		if ((sechdrs[i].sh_flags & SHF_ALLOC) &&
		    (sechdrs[i].sh_type == SHT_NOTE))
			++notes;

	if (notes == 0)
		return;

	notes_attrs = kzalloc(sizeof(*notes_attrs)
			      + notes * sizeof(notes_attrs->attrs[0]),
			      GFP_KERNEL);
	if (notes_attrs == NULL)
		return;

	notes_attrs->notes = notes;
	nattr = &notes_attrs->attrs[0];
	for (loaded = i = 0; i < nsect; ++i) {
		if (!(sechdrs[i].sh_flags & SHF_ALLOC))
			continue;
		if (sechdrs[i].sh_type == SHT_NOTE) {
			nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
			nattr->attr.mode = S_IRUGO;
			nattr->size = sechdrs[i].sh_size;
			nattr->private = (void *) sechdrs[i].sh_addr;
			nattr->read = module_notes_read;
			++nattr;
		}
		++loaded;
	}

1190
	notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
R
Roland McGrath 已提交
1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211
	if (!notes_attrs->dir)
		goto out;

	for (i = 0; i < notes; ++i)
		if (sysfs_create_bin_file(notes_attrs->dir,
					  &notes_attrs->attrs[i]))
			goto out;

	mod->notes_attrs = notes_attrs;
	return;

  out:
	free_notes_attrs(notes_attrs, i);
}

static void remove_notes_attrs(struct module *mod)
{
	if (mod->notes_attrs)
		free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
}

L
Linus Torvalds 已提交
1212
#else
1213

L
Linus Torvalds 已提交
1214 1215 1216 1217 1218 1219 1220 1221
static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
		char *sectstrings, Elf_Shdr *sechdrs)
{
}

static inline void remove_sect_attrs(struct module *mod)
{
}
R
Roland McGrath 已提交
1222 1223 1224 1225 1226 1227 1228 1229 1230

static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
				   char *sectstrings, Elf_Shdr *sechdrs)
{
}

static inline void remove_notes_attrs(struct module *mod)
{
}
1231
#endif
L
Linus Torvalds 已提交
1232

1233 1234
#ifdef CONFIG_SYSFS
int module_add_modinfo_attrs(struct module *mod)
1235 1236
{
	struct module_attribute *attr;
1237
	struct module_attribute *temp_attr;
1238 1239 1240
	int error = 0;
	int i;

1241 1242 1243 1244 1245 1246 1247
	mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
					(ARRAY_SIZE(modinfo_attrs) + 1)),
					GFP_KERNEL);
	if (!mod->modinfo_attrs)
		return -ENOMEM;

	temp_attr = mod->modinfo_attrs;
1248 1249
	for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
		if (!attr->test ||
1250 1251 1252 1253 1254
		    (attr->test && attr->test(mod))) {
			memcpy(temp_attr, attr, sizeof(*temp_attr));
			error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
			++temp_attr;
		}
1255 1256 1257 1258
	}
	return error;
}

1259
void module_remove_modinfo_attrs(struct module *mod)
1260 1261 1262 1263
{
	struct module_attribute *attr;
	int i;

1264 1265 1266 1267
	for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
		/* pick a field to test for end of list */
		if (!attr->attr.name)
			break;
1268
		sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1269 1270
		if (attr->free)
			attr->free(mod);
1271
	}
1272
	kfree(mod->modinfo_attrs);
1273
}
L
Linus Torvalds 已提交
1274

1275
int mod_sysfs_init(struct module *mod)
L
Linus Torvalds 已提交
1276 1277
{
	int err;
1278
	struct kobject *kobj;
L
Linus Torvalds 已提交
1279

1280 1281
	if (!module_sysfs_initialized) {
		printk(KERN_ERR "%s: module sysfs not initialized\n",
1282 1283 1284 1285
		       mod->name);
		err = -EINVAL;
		goto out;
	}
1286 1287 1288 1289 1290 1291 1292 1293 1294

	kobj = kset_find_obj(module_kset, mod->name);
	if (kobj) {
		printk(KERN_ERR "%s: module is already loaded\n", mod->name);
		kobject_put(kobj);
		err = -EINVAL;
		goto out;
	}

L
Linus Torvalds 已提交
1295
	mod->mkobj.mod = mod;
1296

1297 1298 1299 1300 1301 1302
	memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
	mod->mkobj.kobj.kset = module_kset;
	err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
				   "%s", mod->name);
	if (err)
		kobject_put(&mod->mkobj.kobj);
K
Kay Sievers 已提交
1303

1304
	/* delay uevent until full sysfs population */
K
Kay Sievers 已提交
1305 1306 1307 1308
out:
	return err;
}

1309
int mod_sysfs_setup(struct module *mod,
K
Kay Sievers 已提交
1310 1311 1312 1313 1314
			   struct kernel_param *kparam,
			   unsigned int num_params)
{
	int err;

1315
	mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1316 1317
	if (!mod->holders_dir) {
		err = -ENOMEM;
K
Kay Sievers 已提交
1318
		goto out_unreg;
1319
	}
K
Kay Sievers 已提交
1320

L
Linus Torvalds 已提交
1321 1322
	err = module_param_sysfs_setup(mod, kparam, num_params);
	if (err)
K
Kay Sievers 已提交
1323
		goto out_unreg_holders;
L
Linus Torvalds 已提交
1324

1325 1326
	err = module_add_modinfo_attrs(mod);
	if (err)
1327
		goto out_unreg_param;
1328

1329
	kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
L
Linus Torvalds 已提交
1330 1331
	return 0;

1332 1333
out_unreg_param:
	module_param_sysfs_remove(mod);
K
Kay Sievers 已提交
1334
out_unreg_holders:
1335
	kobject_put(mod->holders_dir);
K
Kay Sievers 已提交
1336
out_unreg:
1337
	kobject_put(&mod->mkobj.kobj);
L
Linus Torvalds 已提交
1338 1339
	return err;
}
1340
#endif
L
Linus Torvalds 已提交
1341 1342 1343

static void mod_kobject_remove(struct module *mod)
{
1344
	module_remove_modinfo_attrs(mod);
L
Linus Torvalds 已提交
1345
	module_param_sysfs_remove(mod);
1346 1347 1348
	kobject_put(mod->mkobj.drivers_dir);
	kobject_put(mod->holders_dir);
	kobject_put(&mod->mkobj.kobj);
L
Linus Torvalds 已提交
1349 1350
}

1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361
/*
 * link the module with the whole machine is stopped with interrupts off
 * - this defends against kallsyms not taking locks
 */
static int __link_module(void *_mod)
{
	struct module *mod = _mod;
	list_add(&mod->list, &modules);
	return 0;
}

L
Linus Torvalds 已提交
1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372
/*
 * unlink the module with the whole machine is stopped with interrupts off
 * - this defends against kallsyms not taking locks
 */
static int __unlink_module(void *_mod)
{
	struct module *mod = _mod;
	list_del(&mod->list);
	return 0;
}

1373
/* Free a module, remove from lists, etc (must hold module_mutex). */
L
Linus Torvalds 已提交
1374 1375 1376 1377
static void free_module(struct module *mod)
{
	/* Delete from various lists */
	stop_machine_run(__unlink_module, mod, NR_CPUS);
R
Roland McGrath 已提交
1378
	remove_notes_attrs(mod);
L
Linus Torvalds 已提交
1379 1380 1381
	remove_sect_attrs(mod);
	mod_kobject_remove(mod);

1382 1383
	unwind_remove_table(mod->unwind_info, 0);

L
Linus Torvalds 已提交
1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395
	/* Arch-specific cleanup. */
	module_arch_cleanup(mod);

	/* Module unload stuff */
	module_unload_free(mod);

	/* This may be NULL, but that's OK */
	module_free(mod, mod->module_init);
	kfree(mod->args);
	if (mod->percpu)
		percpu_modfree(mod->percpu);

I
Ingo Molnar 已提交
1396 1397 1398
	/* Free lock-classes: */
	lockdep_free_key_range(mod->module_core, mod->core_size);

L
Linus Torvalds 已提交
1399 1400 1401 1402 1403 1404 1405
	/* Finally, free the core (containing the module structure) */
	module_free(mod, mod->module_core);
}

void *__symbol_get(const char *symbol)
{
	struct module *owner;
R
Rusty Russell 已提交
1406
	unsigned long value;
L
Linus Torvalds 已提交
1407

R
Rusty Russell 已提交
1408
	preempt_disable();
1409
	value = find_symbol(symbol, &owner, NULL, true, true);
1410 1411 1412
	if (IS_ERR_VALUE(value))
		value = 0;
	else if (strong_try_module_get(owner))
L
Linus Torvalds 已提交
1413
		value = 0;
R
Rusty Russell 已提交
1414
	preempt_enable();
L
Linus Torvalds 已提交
1415 1416 1417 1418 1419

	return (void *)value;
}
EXPORT_SYMBOL_GPL(__symbol_get);

1420 1421
/*
 * Ensure that an exported symbol [global namespace] does not already exist
1422
 * in the kernel or in some other module's exported symbol table.
1423 1424 1425
 */
static int verify_export_symbols(struct module *mod)
{
1426
	unsigned int i;
1427
	struct module *owner;
1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438
	const struct kernel_symbol *s;
	struct {
		const struct kernel_symbol *sym;
		unsigned int num;
	} arr[] = {
		{ mod->syms, mod->num_syms },
		{ mod->gpl_syms, mod->num_gpl_syms },
		{ mod->gpl_future_syms, mod->num_gpl_future_syms },
		{ mod->unused_syms, mod->num_unused_syms },
		{ mod->unused_gpl_syms, mod->num_unused_gpl_syms },
	};
1439

1440 1441 1442 1443 1444 1445 1446 1447 1448 1449
	for (i = 0; i < ARRAY_SIZE(arr); i++) {
		for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
			if (!IS_ERR_VALUE(find_symbol(s->name, &owner,
						      NULL, true, false))) {
				printk(KERN_ERR
				       "%s: exports duplicate symbol %s"
				       " (owned by %s)\n",
				       mod->name, s->name, module_name(owner));
				return -ENOEXEC;
			}
1450
		}
1451 1452
	}
	return 0;
1453 1454
}

1455
/* Change all symbols so that st_value encodes the pointer directly. */
L
Linus Torvalds 已提交
1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490
static int simplify_symbols(Elf_Shdr *sechdrs,
			    unsigned int symindex,
			    const char *strtab,
			    unsigned int versindex,
			    unsigned int pcpuindex,
			    struct module *mod)
{
	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
	unsigned long secbase;
	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
	int ret = 0;

	for (i = 1; i < n; i++) {
		switch (sym[i].st_shndx) {
		case SHN_COMMON:
			/* We compiled with -fno-common.  These are not
			   supposed to happen.  */
			DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
			printk("%s: please compile with -fno-common\n",
			       mod->name);
			ret = -ENOEXEC;
			break;

		case SHN_ABS:
			/* Don't need to do anything */
			DEBUGP("Absolute symbol: 0x%08lx\n",
			       (long)sym[i].st_value);
			break;

		case SHN_UNDEF:
			sym[i].st_value
			  = resolve_symbol(sechdrs, versindex,
					   strtab + sym[i].st_name, mod);

			/* Ok if resolved.  */
1491
			if (!IS_ERR_VALUE(sym[i].st_value))
L
Linus Torvalds 已提交
1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591
				break;
			/* Ok if weak.  */
			if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
				break;

			printk(KERN_WARNING "%s: Unknown symbol %s\n",
			       mod->name, strtab + sym[i].st_name);
			ret = -ENOENT;
			break;

		default:
			/* Divert to percpu allocation if a percpu var. */
			if (sym[i].st_shndx == pcpuindex)
				secbase = (unsigned long)mod->percpu;
			else
				secbase = sechdrs[sym[i].st_shndx].sh_addr;
			sym[i].st_value += secbase;
			break;
		}
	}

	return ret;
}

/* Update size with this section: return offset. */
static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
{
	long ret;

	ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
	*size = ret + sechdr->sh_size;
	return ret;
}

/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
   might -- code, read-only data, read-write data, small data.  Tally
   sizes, and place the offsets into sh_entsize fields: high bit means it
   belongs in init. */
static void layout_sections(struct module *mod,
			    const Elf_Ehdr *hdr,
			    Elf_Shdr *sechdrs,
			    const char *secstrings)
{
	static unsigned long const masks[][2] = {
		/* NOTE: all executable code must be the first section
		 * in this array; otherwise modify the text_size
		 * finder in the two loops below */
		{ SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
		{ SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
		{ SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
		{ ARCH_SHF_SMALL | SHF_ALLOC, 0 }
	};
	unsigned int m, i;

	for (i = 0; i < hdr->e_shnum; i++)
		sechdrs[i].sh_entsize = ~0UL;

	DEBUGP("Core section allocation order:\n");
	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
		for (i = 0; i < hdr->e_shnum; ++i) {
			Elf_Shdr *s = &sechdrs[i];

			if ((s->sh_flags & masks[m][0]) != masks[m][0]
			    || (s->sh_flags & masks[m][1])
			    || s->sh_entsize != ~0UL
			    || strncmp(secstrings + s->sh_name,
				       ".init", 5) == 0)
				continue;
			s->sh_entsize = get_offset(&mod->core_size, s);
			DEBUGP("\t%s\n", secstrings + s->sh_name);
		}
		if (m == 0)
			mod->core_text_size = mod->core_size;
	}

	DEBUGP("Init section allocation order:\n");
	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
		for (i = 0; i < hdr->e_shnum; ++i) {
			Elf_Shdr *s = &sechdrs[i];

			if ((s->sh_flags & masks[m][0]) != masks[m][0]
			    || (s->sh_flags & masks[m][1])
			    || s->sh_entsize != ~0UL
			    || strncmp(secstrings + s->sh_name,
				       ".init", 5) != 0)
				continue;
			s->sh_entsize = (get_offset(&mod->init_size, s)
					 | INIT_OFFSET_MASK);
			DEBUGP("\t%s\n", secstrings + s->sh_name);
		}
		if (m == 0)
			mod->init_text_size = mod->init_size;
	}
}

static void set_license(struct module *mod, const char *license)
{
	if (!license)
		license = "unspecified";

1592 1593
	if (!license_is_gpl_compatible(license)) {
		if (!(tainted & TAINT_PROPRIETARY_MODULE))
1594
			printk(KERN_WARNING "%s: module license '%s' taints "
1595 1596
				"kernel.\n", mod->name, license);
		add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
L
Linus Torvalds 已提交
1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633
	}
}

/* Parse tag=value strings from .modinfo section */
static char *next_string(char *string, unsigned long *secsize)
{
	/* Skip non-zero chars */
	while (string[0]) {
		string++;
		if ((*secsize)-- <= 1)
			return NULL;
	}

	/* Skip any zero padding. */
	while (!string[0]) {
		string++;
		if ((*secsize)-- <= 1)
			return NULL;
	}
	return string;
}

static char *get_modinfo(Elf_Shdr *sechdrs,
			 unsigned int info,
			 const char *tag)
{
	char *p;
	unsigned int taglen = strlen(tag);
	unsigned long size = sechdrs[info].sh_size;

	for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
		if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
			return p + taglen + 1;
	}
	return NULL;
}

1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648
static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
			  unsigned int infoindex)
{
	struct module_attribute *attr;
	int i;

	for (i = 0; (attr = modinfo_attrs[i]); i++) {
		if (attr->setup)
			attr->setup(mod,
				    get_modinfo(sechdrs,
						infoindex,
						attr->attr.name));
	}
}

L
Linus Torvalds 已提交
1649
#ifdef CONFIG_KALLSYMS
1650
static int is_exported(const char *name, const struct module *mod)
L
Linus Torvalds 已提交
1651
{
1652 1653 1654
	if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
		return 1;
	else
1655
		if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
L
Linus Torvalds 已提交
1656
			return 1;
1657 1658
		else
			return 0;
L
Linus Torvalds 已提交
1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737
}

/* As per nm */
static char elf_type(const Elf_Sym *sym,
		     Elf_Shdr *sechdrs,
		     const char *secstrings,
		     struct module *mod)
{
	if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
		if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
			return 'v';
		else
			return 'w';
	}
	if (sym->st_shndx == SHN_UNDEF)
		return 'U';
	if (sym->st_shndx == SHN_ABS)
		return 'a';
	if (sym->st_shndx >= SHN_LORESERVE)
		return '?';
	if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
		return 't';
	if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
	    && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
		if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
			return 'r';
		else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
			return 'g';
		else
			return 'd';
	}
	if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
		if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
			return 's';
		else
			return 'b';
	}
	if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
		    ".debug", strlen(".debug")) == 0)
		return 'n';
	return '?';
}

static void add_kallsyms(struct module *mod,
			 Elf_Shdr *sechdrs,
			 unsigned int symindex,
			 unsigned int strindex,
			 const char *secstrings)
{
	unsigned int i;

	mod->symtab = (void *)sechdrs[symindex].sh_addr;
	mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
	mod->strtab = (void *)sechdrs[strindex].sh_addr;

	/* Set types up while we still have access to sections. */
	for (i = 0; i < mod->num_symtab; i++)
		mod->symtab[i].st_info
			= elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
}
#else
static inline void add_kallsyms(struct module *mod,
				Elf_Shdr *sechdrs,
				unsigned int symindex,
				unsigned int strindex,
				const char *secstrings)
{
}
#endif /* CONFIG_KALLSYMS */

/* Allocate and load the module: note that size of section 0 is always
   zero, and we rely on this for optional sections. */
static struct module *load_module(void __user *umod,
				  unsigned long len,
				  const char __user *uargs)
{
	Elf_Ehdr *hdr;
	Elf_Shdr *sechdrs;
	char *secstrings, *args, *modmagic, *strtab = NULL;
A
Andrew Morton 已提交
1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758
	unsigned int i;
	unsigned int symindex = 0;
	unsigned int strindex = 0;
	unsigned int setupindex;
	unsigned int exindex;
	unsigned int exportindex;
	unsigned int modindex;
	unsigned int obsparmindex;
	unsigned int infoindex;
	unsigned int gplindex;
	unsigned int crcindex;
	unsigned int gplcrcindex;
	unsigned int versindex;
	unsigned int pcpuindex;
	unsigned int gplfutureindex;
	unsigned int gplfuturecrcindex;
	unsigned int unwindex = 0;
	unsigned int unusedindex;
	unsigned int unusedcrcindex;
	unsigned int unusedgplindex;
	unsigned int unusedgplcrcindex;
M
Mathieu Desnoyers 已提交
1759 1760
	unsigned int markersindex;
	unsigned int markersstringsindex;
L
Linus Torvalds 已提交
1761 1762 1763 1764
	struct module *mod;
	long err = 0;
	void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
	struct exception_table_entry *extable;
1765
	mm_segment_t old_fs;
L
Linus Torvalds 已提交
1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782

	DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
	       umod, len, uargs);
	if (len < sizeof(*hdr))
		return ERR_PTR(-ENOEXEC);

	/* Suck in entire file: we'll want most of it. */
	/* vmalloc barfs on "unusual" numbers.  Check here */
	if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
		return ERR_PTR(-ENOMEM);
	if (copy_from_user(hdr, umod, len) != 0) {
		err = -EFAULT;
		goto free_hdr;
	}

	/* Sanity checks against insmoding binaries or wrong arch,
           weird elf version */
1783
	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
L
Linus Torvalds 已提交
1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839
	    || hdr->e_type != ET_REL
	    || !elf_check_arch(hdr)
	    || hdr->e_shentsize != sizeof(*sechdrs)) {
		err = -ENOEXEC;
		goto free_hdr;
	}

	if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
		goto truncated;

	/* Convenience variables */
	sechdrs = (void *)hdr + hdr->e_shoff;
	secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
	sechdrs[0].sh_addr = 0;

	for (i = 1; i < hdr->e_shnum; i++) {
		if (sechdrs[i].sh_type != SHT_NOBITS
		    && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
			goto truncated;

		/* Mark all sections sh_addr with their address in the
		   temporary image. */
		sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;

		/* Internal symbols and strings. */
		if (sechdrs[i].sh_type == SHT_SYMTAB) {
			symindex = i;
			strindex = sechdrs[i].sh_link;
			strtab = (char *)hdr + sechdrs[strindex].sh_offset;
		}
#ifndef CONFIG_MODULE_UNLOAD
		/* Don't load .exit sections */
		if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
			sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
#endif
	}

	modindex = find_sec(hdr, sechdrs, secstrings,
			    ".gnu.linkonce.this_module");
	if (!modindex) {
		printk(KERN_WARNING "No module found in object\n");
		err = -ENOEXEC;
		goto free_hdr;
	}
	mod = (void *)sechdrs[modindex].sh_addr;

	if (symindex == 0) {
		printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
		       mod->name);
		err = -ENOEXEC;
		goto free_hdr;
	}

	/* Optional sections */
	exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
	gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1840
	gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
1841 1842
	unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
	unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
L
Linus Torvalds 已提交
1843 1844
	crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
	gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1845
	gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
1846 1847
	unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
	unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
L
Linus Torvalds 已提交
1848 1849 1850 1851 1852 1853
	setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
	exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
	obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
	versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
	infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
	pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
1854 1855 1856
#ifdef ARCH_UNWIND_SECTION_NAME
	unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
#endif
L
Linus Torvalds 已提交
1857

1858
	/* Don't keep modinfo and version sections. */
L
Linus Torvalds 已提交
1859
	sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1860
	sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
L
Linus Torvalds 已提交
1861 1862 1863 1864 1865
#ifdef CONFIG_KALLSYMS
	/* Keep symbol and string tables for decoding later. */
	sechdrs[symindex].sh_flags |= SHF_ALLOC;
	sechdrs[strindex].sh_flags |= SHF_ALLOC;
#endif
1866 1867
	if (unwindex)
		sechdrs[unwindex].sh_flags |= SHF_ALLOC;
L
Linus Torvalds 已提交
1868 1869 1870 1871 1872 1873 1874 1875 1876 1877

	/* Check module struct version now, before we try to use module. */
	if (!check_modstruct_version(sechdrs, versindex, mod)) {
		err = -ENOEXEC;
		goto free_hdr;
	}

	modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
	/* This is allowed: modprobe --force will invalidate it. */
	if (!modmagic) {
1878 1879 1880
		err = try_to_force_load(mod, "magic");
		if (err)
			goto free_hdr;
1881
	} else if (!same_magic(modmagic, vermagic, versindex)) {
L
Linus Torvalds 已提交
1882 1883 1884 1885 1886 1887 1888
		printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
		       mod->name, modmagic, vermagic);
		err = -ENOEXEC;
		goto free_hdr;
	}

	/* Now copy in args */
1889 1890 1891
	args = strndup_user(uargs, ~0UL >> 1);
	if (IS_ERR(args)) {
		err = PTR_ERR(args);
L
Linus Torvalds 已提交
1892 1893
		goto free_hdr;
	}
1894

L
Linus Torvalds 已提交
1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909
	if (find_module(mod->name)) {
		err = -EEXIST;
		goto free_mod;
	}

	mod->state = MODULE_STATE_COMING;

	/* Allow arches to frob section contents and sizes.  */
	err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
	if (err < 0)
		goto free_mod;

	if (pcpuindex) {
		/* We have a special allocation for this section. */
		percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
1910 1911
					 sechdrs[pcpuindex].sh_addralign,
					 mod->name);
L
Linus Torvalds 已提交
1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968
		if (!percpu) {
			err = -ENOMEM;
			goto free_mod;
		}
		sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
		mod->percpu = percpu;
	}

	/* Determine total sizes, and put offsets in sh_entsize.  For now
	   this is done generically; there doesn't appear to be any
	   special cases for the architectures. */
	layout_sections(mod, hdr, sechdrs, secstrings);

	/* Do the allocs. */
	ptr = module_alloc(mod->core_size);
	if (!ptr) {
		err = -ENOMEM;
		goto free_percpu;
	}
	memset(ptr, 0, mod->core_size);
	mod->module_core = ptr;

	ptr = module_alloc(mod->init_size);
	if (!ptr && mod->init_size) {
		err = -ENOMEM;
		goto free_core;
	}
	memset(ptr, 0, mod->init_size);
	mod->module_init = ptr;

	/* Transfer each section which specifies SHF_ALLOC */
	DEBUGP("final section addresses:\n");
	for (i = 0; i < hdr->e_shnum; i++) {
		void *dest;

		if (!(sechdrs[i].sh_flags & SHF_ALLOC))
			continue;

		if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
			dest = mod->module_init
				+ (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
		else
			dest = mod->module_core + sechdrs[i].sh_entsize;

		if (sechdrs[i].sh_type != SHT_NOBITS)
			memcpy(dest, (void *)sechdrs[i].sh_addr,
			       sechdrs[i].sh_size);
		/* Update sh_addr to point to copy in image. */
		sechdrs[i].sh_addr = (unsigned long)dest;
		DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
	}
	/* Module has been moved. */
	mod = (void *)sechdrs[modindex].sh_addr;

	/* Now we've moved module, initialize linked lists, etc. */
	module_unload_init(mod);

1969
	/* add kobject, so we can reference it. */
1970 1971
	err = mod_sysfs_init(mod);
	if (err)
1972
		goto free_unload;
K
Kay Sievers 已提交
1973

L
Linus Torvalds 已提交
1974 1975 1976
	/* Set up license info based on the info section */
	set_license(mod, get_modinfo(sechdrs, infoindex, "license"));

1977 1978 1979 1980 1981
	/*
	 * ndiswrapper is under GPL by itself, but loads proprietary modules.
	 * Don't use add_taint_module(), as it would prevent ndiswrapper from
	 * using GPL-only symbols it needs.
	 */
1982
	if (strcmp(mod->name, "ndiswrapper") == 0)
1983 1984 1985
		add_taint(TAINT_PROPRIETARY_MODULE);

	/* driverloader was caught wrongly pretending to be under GPL */
1986 1987
	if (strcmp(mod->name, "driverloader") == 0)
		add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1988

1989 1990 1991
	/* Set up MODINFO_ATTR fields */
	setup_modinfo(mod, sechdrs, infoindex);

L
Linus Torvalds 已提交
1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
	/* Fix up syms, so that st_value is a pointer to location. */
	err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
			       mod);
	if (err < 0)
		goto cleanup;

	/* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
	mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
	mod->syms = (void *)sechdrs[exportindex].sh_addr;
	if (crcindex)
		mod->crcs = (void *)sechdrs[crcindex].sh_addr;
	mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
	mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
	if (gplcrcindex)
		mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
2007 2008
	mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
					sizeof(*mod->gpl_future_syms);
2009 2010 2011 2012
	mod->num_unused_syms = sechdrs[unusedindex].sh_size /
					sizeof(*mod->unused_syms);
	mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
					sizeof(*mod->unused_gpl_syms);
2013 2014 2015
	mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
	if (gplfuturecrcindex)
		mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
L
Linus Torvalds 已提交
2016

2017 2018 2019 2020 2021
	mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
	if (unusedcrcindex)
		mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
	mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
	if (unusedgplcrcindex)
2022 2023
		mod->unused_gpl_crcs
			= (void *)sechdrs[unusedgplcrcindex].sh_addr;
2024

L
Linus Torvalds 已提交
2025
#ifdef CONFIG_MODVERSIONS
D
Daniel Walker 已提交
2026
	if ((mod->num_syms && !crcindex) ||
2027
	    (mod->num_gpl_syms && !gplcrcindex) ||
2028 2029 2030
	    (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
	    (mod->num_unused_syms && !unusedcrcindex) ||
	    (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
2031 2032 2033 2034
		printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name);
		err = try_to_force_load(mod, "nocrc");
		if (err)
			goto cleanup;
L
Linus Torvalds 已提交
2035 2036
	}
#endif
M
Mathieu Desnoyers 已提交
2037 2038 2039
	markersindex = find_sec(hdr, sechdrs, secstrings, "__markers");
 	markersstringsindex = find_sec(hdr, sechdrs, secstrings,
					"__markers_strings");
L
Linus Torvalds 已提交
2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061

	/* Now do relocations. */
	for (i = 1; i < hdr->e_shnum; i++) {
		const char *strtab = (char *)sechdrs[strindex].sh_addr;
		unsigned int info = sechdrs[i].sh_info;

		/* Not a valid relocation section? */
		if (info >= hdr->e_shnum)
			continue;

		/* Don't bother with non-allocated sections */
		if (!(sechdrs[info].sh_flags & SHF_ALLOC))
			continue;

		if (sechdrs[i].sh_type == SHT_REL)
			err = apply_relocate(sechdrs, strtab, symindex, i,mod);
		else if (sechdrs[i].sh_type == SHT_RELA)
			err = apply_relocate_add(sechdrs, strtab, symindex, i,
						 mod);
		if (err < 0)
			goto cleanup;
	}
M
Mathieu Desnoyers 已提交
2062 2063 2064 2065 2066
#ifdef CONFIG_MARKERS
	mod->markers = (void *)sechdrs[markersindex].sh_addr;
	mod->num_markers =
		sechdrs[markersindex].sh_size / sizeof(*mod->markers);
#endif
L
Linus Torvalds 已提交
2067

2068 2069 2070 2071 2072 2073
        /* Find duplicate symbols */
	err = verify_export_symbols(mod);

	if (err < 0)
		goto cleanup;

L
Linus Torvalds 已提交
2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084
  	/* Set up and sort exception table */
	mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
	mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
	sort_extable(extable, extable + mod->num_exentries);

	/* Finally, copy percpu area over. */
	percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
		       sechdrs[pcpuindex].sh_size);

	add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);

M
Mathieu Desnoyers 已提交
2085 2086 2087
#ifdef CONFIG_MARKERS
	if (!mod->taints)
		marker_update_probe_range(mod->markers,
2088
			mod->markers + mod->num_markers);
M
Mathieu Desnoyers 已提交
2089
#endif
L
Linus Torvalds 已提交
2090 2091 2092 2093
	err = module_finalize(hdr, sechdrs, mod);
	if (err < 0)
		goto cleanup;

2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111
	/* flush the icache in correct context */
	old_fs = get_fs();
	set_fs(KERNEL_DS);

	/*
	 * Flush the instruction cache, since we've played with text.
	 * Do it before processing of module parameters, so the module
	 * can provide parameter accessor functions of its own.
	 */
	if (mod->module_init)
		flush_icache_range((unsigned long)mod->module_init,
				   (unsigned long)mod->module_init
				   + mod->init_size);
	flush_icache_range((unsigned long)mod->module_core,
			   (unsigned long)mod->module_core + mod->core_size);

	set_fs(old_fs);

L
Linus Torvalds 已提交
2112
	mod->args = args;
R
Rusty Russell 已提交
2113 2114 2115 2116
	if (obsparmindex)
		printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
		       mod->name);

2117 2118 2119 2120 2121
	/* Now sew it into the lists so we can get lockdep and oops
         * info during argument parsing.  Noone should access us, since
         * strong_try_module_get() will fail. */
	stop_machine_run(__link_module, mod, NR_CPUS);

R
Rusty Russell 已提交
2122 2123 2124 2125 2126 2127 2128
	/* Size of section 0 is 0, so this works well if no params */
	err = parse_args(mod->name, mod->args,
			 (struct kernel_param *)
			 sechdrs[setupindex].sh_addr,
			 sechdrs[setupindex].sh_size
			 / sizeof(struct kernel_param),
			 NULL);
L
Linus Torvalds 已提交
2129
	if (err < 0)
2130
		goto unlink;
L
Linus Torvalds 已提交
2131

D
Daniel Walker 已提交
2132
	err = mod_sysfs_setup(mod,
L
Linus Torvalds 已提交
2133 2134 2135 2136 2137
			      (struct kernel_param *)
			      sechdrs[setupindex].sh_addr,
			      sechdrs[setupindex].sh_size
			      / sizeof(struct kernel_param));
	if (err < 0)
2138
		goto unlink;
L
Linus Torvalds 已提交
2139
	add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
R
Roland McGrath 已提交
2140
	add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
L
Linus Torvalds 已提交
2141

2142 2143
	/* Size of section 0 is 0, so this works well if no unwind info. */
	mod->unwind_info = unwind_add_table(mod,
D
Daniel Walker 已提交
2144 2145
					    (void *)sechdrs[unwindex].sh_addr,
					    sechdrs[unwindex].sh_size);
2146

L
Linus Torvalds 已提交
2147 2148 2149 2150 2151 2152
	/* Get rid of temporary copy */
	vfree(hdr);

	/* Done! */
	return mod;

2153 2154
 unlink:
	stop_machine_run(__unlink_module, mod, NR_CPUS);
L
Linus Torvalds 已提交
2155 2156
	module_arch_cleanup(mod);
 cleanup:
2157 2158 2159
	kobject_del(&mod->mkobj.kobj);
	kobject_put(&mod->mkobj.kobj);
 free_unload:
L
Linus Torvalds 已提交
2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170
	module_unload_free(mod);
	module_free(mod, mod->module_init);
 free_core:
	module_free(mod, mod->module_core);
 free_percpu:
	if (percpu)
		percpu_modfree(percpu);
 free_mod:
	kfree(args);
 free_hdr:
	vfree(hdr);
2171
	return ERR_PTR(err);
L
Linus Torvalds 已提交
2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192

 truncated:
	printk(KERN_ERR "Module len %lu truncated\n", len);
	err = -ENOEXEC;
	goto free_hdr;
}

/* This is where the real work happens */
asmlinkage long
sys_init_module(void __user *umod,
		unsigned long len,
		const char __user *uargs)
{
	struct module *mod;
	int ret = 0;

	/* Must have permission */
	if (!capable(CAP_SYS_MODULE))
		return -EPERM;

	/* Only one module load at a time, please */
2193
	if (mutex_lock_interruptible(&module_mutex) != 0)
L
Linus Torvalds 已提交
2194 2195 2196 2197 2198
		return -EINTR;

	/* Do all the hard work */
	mod = load_module(umod, len, uargs);
	if (IS_ERR(mod)) {
2199
		mutex_unlock(&module_mutex);
L
Linus Torvalds 已提交
2200 2201 2202 2203
		return PTR_ERR(mod);
	}

	/* Drop lock so they can recurse */
2204
	mutex_unlock(&module_mutex);
L
Linus Torvalds 已提交
2205

2206 2207
	blocking_notifier_call_chain(&module_notify_list,
			MODULE_STATE_COMING, mod);
L
Linus Torvalds 已提交
2208 2209 2210 2211 2212 2213 2214 2215

	/* Start the module */
	if (mod->init != NULL)
		ret = mod->init();
	if (ret < 0) {
		/* Init routine failed: abort.  Try to protect us from
                   buggy refcounters. */
		mod->state = MODULE_STATE_GOING;
2216
		synchronize_sched();
R
Rusty Russell 已提交
2217
		module_put(mod);
2218 2219
		blocking_notifier_call_chain(&module_notify_list,
					     MODULE_STATE_GOING, mod);
R
Rusty Russell 已提交
2220 2221 2222
		mutex_lock(&module_mutex);
		free_module(mod);
		mutex_unlock(&module_mutex);
2223
		wake_up(&module_wq);
L
Linus Torvalds 已提交
2224 2225
		return ret;
	}
2226 2227 2228 2229 2230 2231 2232 2233
	if (ret > 0) {
		printk(KERN_WARNING "%s: '%s'->init suspiciously returned %d, "
				    "it should follow 0/-E convention\n"
		       KERN_WARNING "%s: loading module anyway...\n",
		       __func__, mod->name, ret,
		       __func__);
		dump_stack();
	}
L
Linus Torvalds 已提交
2234

2235
	/* Now it's a first class citizen!  Wake up anyone waiting for it. */
L
Linus Torvalds 已提交
2236
	mod->state = MODULE_STATE_LIVE;
2237 2238 2239
	wake_up(&module_wq);

	mutex_lock(&module_mutex);
L
Linus Torvalds 已提交
2240 2241
	/* Drop initial reference. */
	module_put(mod);
2242
	unwind_remove_table(mod->unwind_info, 1);
L
Linus Torvalds 已提交
2243 2244 2245 2246
	module_free(mod, mod->module_init);
	mod->module_init = NULL;
	mod->init_size = 0;
	mod->init_text_size = 0;
2247
	mutex_unlock(&module_mutex);
L
Linus Torvalds 已提交
2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263

	return 0;
}

static inline int within(unsigned long addr, void *start, unsigned long size)
{
	return ((void *)addr >= start && (void *)addr < start + size);
}

#ifdef CONFIG_KALLSYMS
/*
 * This ignores the intensely annoying "mapping symbols" found
 * in ARM ELF files: $a, $t and $d.
 */
static inline int is_arm_mapping_symbol(const char *str)
{
D
Daniel Walker 已提交
2264
	return str[0] == '$' && strchr("atd", str[1])
L
Linus Torvalds 已提交
2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278
	       && (str[2] == '\0' || str[2] == '.');
}

static const char *get_ksymbol(struct module *mod,
			       unsigned long addr,
			       unsigned long *size,
			       unsigned long *offset)
{
	unsigned int i, best = 0;
	unsigned long nextval;

	/* At worse, next value is at end of module */
	if (within(addr, mod->module_init, mod->init_size))
		nextval = (unsigned long)mod->module_init+mod->init_text_size;
D
Daniel Walker 已提交
2279
	else
L
Linus Torvalds 已提交
2280 2281 2282
		nextval = (unsigned long)mod->module_core+mod->core_text_size;

	/* Scan for closest preceeding symbol, and next symbol. (ELF
D
Daniel Walker 已提交
2283
	   starts real symbols at 1). */
L
Linus Torvalds 已提交
2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304
	for (i = 1; i < mod->num_symtab; i++) {
		if (mod->symtab[i].st_shndx == SHN_UNDEF)
			continue;

		/* We ignore unnamed symbols: they're uninformative
		 * and inserted at a whim. */
		if (mod->symtab[i].st_value <= addr
		    && mod->symtab[i].st_value > mod->symtab[best].st_value
		    && *(mod->strtab + mod->symtab[i].st_name) != '\0'
		    && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
			best = i;
		if (mod->symtab[i].st_value > addr
		    && mod->symtab[i].st_value < nextval
		    && *(mod->strtab + mod->symtab[i].st_name) != '\0'
		    && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
			nextval = mod->symtab[i].st_value;
	}

	if (!best)
		return NULL;

A
Alexey Dobriyan 已提交
2305 2306 2307 2308
	if (size)
		*size = nextval - mod->symtab[best].st_value;
	if (offset)
		*offset = addr - mod->symtab[best].st_value;
L
Linus Torvalds 已提交
2309 2310 2311
	return mod->strtab + mod->symtab[best].st_name;
}

2312 2313
/* For kallsyms to ask for address resolution.  NULL means not found.  Careful
 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2314
const char *module_address_lookup(unsigned long addr,
2315 2316 2317 2318
			    unsigned long *size,
			    unsigned long *offset,
			    char **modname,
			    char *namebuf)
L
Linus Torvalds 已提交
2319 2320
{
	struct module *mod;
2321
	const char *ret = NULL;
L
Linus Torvalds 已提交
2322

2323
	preempt_disable();
L
Linus Torvalds 已提交
2324 2325 2326
	list_for_each_entry(mod, &modules, list) {
		if (within(addr, mod->module_init, mod->init_size)
		    || within(addr, mod->module_core, mod->core_size)) {
2327 2328
			if (modname)
				*modname = mod->name;
2329 2330
			ret = get_ksymbol(mod, addr, size, offset);
			break;
L
Linus Torvalds 已提交
2331 2332
		}
	}
2333 2334 2335 2336 2337
	/* Make a copy in here where it's safe */
	if (ret) {
		strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
		ret = namebuf;
	}
2338
	preempt_enable();
2339
	return ret;
L
Linus Torvalds 已提交
2340 2341
}

2342 2343 2344 2345
int lookup_module_symbol_name(unsigned long addr, char *symname)
{
	struct module *mod;

2346
	preempt_disable();
2347 2348 2349 2350 2351 2352 2353 2354
	list_for_each_entry(mod, &modules, list) {
		if (within(addr, mod->module_init, mod->init_size) ||
		    within(addr, mod->module_core, mod->core_size)) {
			const char *sym;

			sym = get_ksymbol(mod, addr, NULL, NULL);
			if (!sym)
				goto out;
2355
			strlcpy(symname, sym, KSYM_NAME_LEN);
2356
			preempt_enable();
2357 2358 2359 2360
			return 0;
		}
	}
out:
2361
	preempt_enable();
2362 2363 2364
	return -ERANGE;
}

2365 2366 2367 2368 2369
int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
			unsigned long *offset, char *modname, char *name)
{
	struct module *mod;

2370
	preempt_disable();
2371 2372 2373 2374 2375 2376 2377 2378 2379
	list_for_each_entry(mod, &modules, list) {
		if (within(addr, mod->module_init, mod->init_size) ||
		    within(addr, mod->module_core, mod->core_size)) {
			const char *sym;

			sym = get_ksymbol(mod, addr, size, offset);
			if (!sym)
				goto out;
			if (modname)
2380
				strlcpy(modname, mod->name, MODULE_NAME_LEN);
2381
			if (name)
2382
				strlcpy(name, sym, KSYM_NAME_LEN);
2383
			preempt_enable();
2384 2385 2386 2387
			return 0;
		}
	}
out:
2388
	preempt_enable();
2389 2390 2391
	return -ERANGE;
}

2392 2393
int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
			char *name, char *module_name, int *exported)
L
Linus Torvalds 已提交
2394 2395 2396
{
	struct module *mod;

2397
	preempt_disable();
L
Linus Torvalds 已提交
2398 2399 2400 2401
	list_for_each_entry(mod, &modules, list) {
		if (symnum < mod->num_symtab) {
			*value = mod->symtab[symnum].st_value;
			*type = mod->symtab[symnum].st_info;
2402
			strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2403 2404
				KSYM_NAME_LEN);
			strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2405
			*exported = is_exported(name, mod);
2406
			preempt_enable();
2407
			return 0;
L
Linus Torvalds 已提交
2408 2409 2410
		}
		symnum -= mod->num_symtab;
	}
2411
	preempt_enable();
2412
	return -ERANGE;
L
Linus Torvalds 已提交
2413 2414 2415 2416 2417 2418 2419
}

static unsigned long mod_find_symname(struct module *mod, const char *name)
{
	unsigned int i;

	for (i = 0; i < mod->num_symtab; i++)
2420 2421
		if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
		    mod->symtab[i].st_info != 'U')
L
Linus Torvalds 已提交
2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433
			return mod->symtab[i].st_value;
	return 0;
}

/* Look for this name: can be of form module:name. */
unsigned long module_kallsyms_lookup_name(const char *name)
{
	struct module *mod;
	char *colon;
	unsigned long ret = 0;

	/* Don't lock: we're in enough trouble already. */
2434
	preempt_disable();
L
Linus Torvalds 已提交
2435 2436 2437 2438 2439 2440 2441 2442 2443 2444
	if ((colon = strchr(name, ':')) != NULL) {
		*colon = '\0';
		if ((mod = find_module(name)) != NULL)
			ret = mod_find_symname(mod, colon+1);
		*colon = ':';
	} else {
		list_for_each_entry(mod, &modules, list)
			if ((ret = mod_find_symname(mod, name)) != 0)
				break;
	}
2445
	preempt_enable();
L
Linus Torvalds 已提交
2446 2447 2448 2449 2450 2451 2452
	return ret;
}
#endif /* CONFIG_KALLSYMS */

/* Called by the /proc file system to return a list of modules. */
static void *m_start(struct seq_file *m, loff_t *pos)
{
2453
	mutex_lock(&module_mutex);
2454
	return seq_list_start(&modules, *pos);
L
Linus Torvalds 已提交
2455 2456 2457 2458
}

static void *m_next(struct seq_file *m, void *p, loff_t *pos)
{
2459
	return seq_list_next(p, &modules, pos);
L
Linus Torvalds 已提交
2460 2461 2462 2463
}

static void m_stop(struct seq_file *m, void *p)
{
2464
	mutex_unlock(&module_mutex);
L
Linus Torvalds 已提交
2465 2466
}

2467
static char *module_flags(struct module *mod, char *buf)
2468 2469 2470
{
	int bx = 0;

2471 2472 2473
	if (mod->taints ||
	    mod->state == MODULE_STATE_GOING ||
	    mod->state == MODULE_STATE_COMING) {
2474
		buf[bx++] = '(';
2475
		if (mod->taints & TAINT_PROPRIETARY_MODULE)
2476
			buf[bx++] = 'P';
2477
		if (mod->taints & TAINT_FORCED_MODULE)
2478 2479 2480 2481 2482 2483
			buf[bx++] = 'F';
		/*
		 * TAINT_FORCED_RMMOD: could be added.
		 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
		 * apply to modules.
		 */
2484 2485 2486 2487 2488 2489 2490

		/* Show a - for module-is-being-unloaded */
		if (mod->state == MODULE_STATE_GOING)
			buf[bx++] = '-';
		/* Show a + for module-is-being-loaded */
		if (mod->state == MODULE_STATE_COMING)
			buf[bx++] = '+';
2491 2492 2493 2494 2495 2496 2497
		buf[bx++] = ')';
	}
	buf[bx] = '\0';

	return buf;
}

L
Linus Torvalds 已提交
2498 2499 2500
static int m_show(struct seq_file *m, void *p)
{
	struct module *mod = list_entry(p, struct module, list);
2501 2502
	char buf[8];

L
Linus Torvalds 已提交
2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514
	seq_printf(m, "%s %lu",
		   mod->name, mod->init_size + mod->core_size);
	print_unload_info(m, mod);

	/* Informative for users. */
	seq_printf(m, " %s",
		   mod->state == MODULE_STATE_GOING ? "Unloading":
		   mod->state == MODULE_STATE_COMING ? "Loading":
		   "Live");
	/* Used by oprofile and other similar tools. */
	seq_printf(m, " 0x%p", mod->module_core);

2515 2516
	/* Taints info */
	if (mod->taints)
2517
		seq_printf(m, " %s", module_flags(mod, buf));
2518

L
Linus Torvalds 已提交
2519 2520 2521 2522 2523 2524 2525 2526 2527
	seq_printf(m, "\n");
	return 0;
}

/* Format: modulename size refcount deps address

   Where refcount is a number or -, and deps is a comma-separated list
   of depends or -.
*/
2528
const struct seq_operations modules_op = {
L
Linus Torvalds 已提交
2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540
	.start	= m_start,
	.next	= m_next,
	.stop	= m_stop,
	.show	= m_show
};

/* Given an address, look for it in the module exception tables. */
const struct exception_table_entry *search_module_extables(unsigned long addr)
{
	const struct exception_table_entry *e = NULL;
	struct module *mod;

R
Rusty Russell 已提交
2541
	preempt_disable();
L
Linus Torvalds 已提交
2542 2543 2544
	list_for_each_entry(mod, &modules, list) {
		if (mod->num_exentries == 0)
			continue;
D
Daniel Walker 已提交
2545

L
Linus Torvalds 已提交
2546 2547 2548 2549 2550 2551
		e = search_extable(mod->extable,
				   mod->extable + mod->num_exentries - 1,
				   addr);
		if (e)
			break;
	}
R
Rusty Russell 已提交
2552
	preempt_enable();
L
Linus Torvalds 已提交
2553 2554

	/* Now, if we found one, we are running inside it now, hence
D
Daniel Walker 已提交
2555
	   we cannot unload the module, hence no refcnt needed. */
L
Linus Torvalds 已提交
2556 2557 2558
	return e;
}

2559 2560 2561 2562 2563 2564 2565
/*
 * Is this a valid module address?
 */
int is_module_address(unsigned long addr)
{
	struct module *mod;

R
Rusty Russell 已提交
2566
	preempt_disable();
2567 2568 2569

	list_for_each_entry(mod, &modules, list) {
		if (within(addr, mod->module_core, mod->core_size)) {
R
Rusty Russell 已提交
2570
			preempt_enable();
2571 2572 2573 2574
			return 1;
		}
	}

R
Rusty Russell 已提交
2575
	preempt_enable();
2576 2577 2578 2579 2580

	return 0;
}


R
Rusty Russell 已提交
2581
/* Is this a valid kernel address? */
L
Linus Torvalds 已提交
2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596
struct module *__module_text_address(unsigned long addr)
{
	struct module *mod;

	list_for_each_entry(mod, &modules, list)
		if (within(addr, mod->module_init, mod->init_text_size)
		    || within(addr, mod->module_core, mod->core_text_size))
			return mod;
	return NULL;
}

struct module *module_text_address(unsigned long addr)
{
	struct module *mod;

R
Rusty Russell 已提交
2597
	preempt_disable();
L
Linus Torvalds 已提交
2598
	mod = __module_text_address(addr);
R
Rusty Russell 已提交
2599
	preempt_enable();
L
Linus Torvalds 已提交
2600 2601 2602 2603 2604 2605 2606 2607

	return mod;
}

/* Don't grab lock, we're oopsing. */
void print_modules(void)
{
	struct module *mod;
2608
	char buf[8];
L
Linus Torvalds 已提交
2609 2610 2611

	printk("Modules linked in:");
	list_for_each_entry(mod, &modules, list)
2612
		printk(" %s%s", mod->name, module_flags(mod, buf));
2613 2614
	if (last_unloaded_module[0])
		printk(" [last unloaded: %s]", last_unloaded_module);
L
Linus Torvalds 已提交
2615 2616 2617 2618 2619 2620 2621 2622
	printk("\n");
}

#ifdef CONFIG_MODVERSIONS
/* Generate the signature for struct module here, too, for modversions. */
void struct_module(struct module *mod) { return; }
EXPORT_SYMBOL(struct_module);
#endif
M
Mathieu Desnoyers 已提交
2623 2624

#ifdef CONFIG_MARKERS
2625
void module_update_markers(void)
M
Mathieu Desnoyers 已提交
2626 2627 2628 2629 2630 2631 2632
{
	struct module *mod;

	mutex_lock(&module_mutex);
	list_for_each_entry(mod, &modules, list)
		if (!mod->taints)
			marker_update_probe_range(mod->markers,
2633
				mod->markers + mod->num_markers);
M
Mathieu Desnoyers 已提交
2634 2635 2636
	mutex_unlock(&module_mutex);
}
#endif