projects/linux·blob v2.6.34-rc5 · refs

3084 lines · 79.0 KiB

1/*
2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18*/
19#include <linux/module.h>
20#include <linux/moduleloader.h>
21#include <linux/ftrace_event.h>
22#include <linux/init.h>
23#include <linux/kallsyms.h>
24#include <linux/fs.h>
25#include <linux/sysfs.h>
26#include <linux/kernel.h>
27#include <linux/slab.h>
28#include <linux/vmalloc.h>
29#include <linux/elf.h>
30#include <linux/proc_fs.h>
31#include <linux/seq_file.h>
32#include <linux/syscalls.h>
33#include <linux/fcntl.h>
34#include <linux/rcupdate.h>
35#include <linux/capability.h>
36#include <linux/cpu.h>
37#include <linux/moduleparam.h>
38#include <linux/errno.h>
39#include <linux/err.h>
40#include <linux/vermagic.h>
41#include <linux/notifier.h>
42#include <linux/sched.h>
43#include <linux/stop_machine.h>
44#include <linux/device.h>
45#include <linux/string.h>
46#include <linux/mutex.h>
47#include <linux/rculist.h>
48#include <asm/uaccess.h>
49#include <asm/cacheflush.h>
50#include <asm/mmu_context.h>
51#include <linux/license.h>
52#include <asm/sections.h>
53#include <linux/tracepoint.h>
54#include <linux/ftrace.h>
55#include <linux/async.h>
56#include <linux/percpu.h>
57#include <linux/kmemleak.h>
58
59#define CREATE_TRACE_POINTS
60#include <trace/events/module.h>
61
62EXPORT_TRACEPOINT_SYMBOL(module_get);
63
64#if 0
65#define DEBUGP printk
66#else
67#define DEBUGP(fmt , a...)
68#endif
69
70#ifndef ARCH_SHF_SMALL
71#define ARCH_SHF_SMALL 0
72#endif
73
74/* If this is set, the section belongs in the init part of the module */
75#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
76
77/* List of modules, protected by module_mutex or preempt_disable
78 * (delete uses stop_machine/add uses RCU list operations). */
79DEFINE_MUTEX(module_mutex);
80EXPORT_SYMBOL_GPL(module_mutex);
81static LIST_HEAD(modules);
82
83/* Block module loading/unloading? */
84int modules_disabled = 0;
85
86/* Waiting for a module to finish initializing? */
87static DECLARE_WAIT_QUEUE_HEAD(module_wq);
88
89static BLOCKING_NOTIFIER_HEAD(module_notify_list);
90
91/* Bounds of module allocation, for speeding __module_address */
92static unsigned long module_addr_min = -1UL, module_addr_max = 0;
93
94int register_module_notifier(struct notifier_block * nb)
95{
96 return blocking_notifier_chain_register(&module_notify_list, nb);
97}
98EXPORT_SYMBOL(register_module_notifier);
99
100int unregister_module_notifier(struct notifier_block * nb)
101{
102 return blocking_notifier_chain_unregister(&module_notify_list, nb);
103}
104EXPORT_SYMBOL(unregister_module_notifier);
105
106/* We require a truly strong try_module_get(): 0 means failure due to
107 ongoing or failed initialization etc. */
108static inline int strong_try_module_get(struct module *mod)
109{
110 if (mod && mod->state == MODULE_STATE_COMING)
111 return -EBUSY;
112 if (try_module_get(mod))
113 return 0;
114 else
115 return -ENOENT;
116}
117
118static inline void add_taint_module(struct module *mod, unsigned flag)
119{
120 add_taint(flag);
121 mod->taints |= (1U << flag);
122}
123
124/*
125 * A thread that wants to hold a reference to a module only while it
126 * is running can call this to safely exit. nfsd and lockd use this.
127 */
128void __module_put_and_exit(struct module *mod, long code)
129{
130 module_put(mod);
131 do_exit(code);
132}
133EXPORT_SYMBOL(__module_put_and_exit);
134
135/* Find a module section: 0 means not found. */
136static unsigned int find_sec(Elf_Ehdr *hdr,
137 Elf_Shdr *sechdrs,
138 const char *secstrings,
139 const char *name)
140{
141 unsigned int i;
142
143 for (i = 1; i < hdr->e_shnum; i++)
144 /* Alloc bit cleared means "ignore it." */
145 if ((sechdrs[i].sh_flags & SHF_ALLOC)
146 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
147 return i;
148 return 0;
149}
150
151/* Find a module section, or NULL. */
152static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
153 const char *secstrings, const char *name)
154{
155 /* Section 0 has sh_addr 0. */
156 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
157}
158
159/* Find a module section, or NULL. Fill in number of "objects" in section. */
160static void *section_objs(Elf_Ehdr *hdr,
161 Elf_Shdr *sechdrs,
162 const char *secstrings,
163 const char *name,
164 size_t object_size,
165 unsigned int *num)
166{
167 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
168
169 /* Section 0 has sh_addr 0 and sh_size 0. */
170 *num = sechdrs[sec].sh_size / object_size;
171 return (void *)sechdrs[sec].sh_addr;
172}
173
174/* Provided by the linker */
175extern const struct kernel_symbol __start___ksymtab[];
176extern const struct kernel_symbol __stop___ksymtab[];
177extern const struct kernel_symbol __start___ksymtab_gpl[];
178extern const struct kernel_symbol __stop___ksymtab_gpl[];
179extern const struct kernel_symbol __start___ksymtab_gpl_future[];
180extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
181extern const struct kernel_symbol __start___ksymtab_gpl_future[];
182extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
183extern const unsigned long __start___kcrctab[];
184extern const unsigned long __start___kcrctab_gpl[];
185extern const unsigned long __start___kcrctab_gpl_future[];
186#ifdef CONFIG_UNUSED_SYMBOLS
187extern const struct kernel_symbol __start___ksymtab_unused[];
188extern const struct kernel_symbol __stop___ksymtab_unused[];
189extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
190extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
191extern const unsigned long __start___kcrctab_unused[];
192extern const unsigned long __start___kcrctab_unused_gpl[];
193#endif
194
195#ifndef CONFIG_MODVERSIONS
196#define symversion(base, idx) NULL
197#else
198#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
199#endif
200
201static bool each_symbol_in_section(const struct symsearch *arr,
202 unsigned int arrsize,
203 struct module *owner,
204 bool (*fn)(const struct symsearch *syms,
205 struct module *owner,
206 unsigned int symnum, void *data),
207 void *data)
208{
209 unsigned int i, j;
210
211 for (j = 0; j < arrsize; j++) {
212 for (i = 0; i < arr[j].stop - arr[j].start; i++)
213 if (fn(&arr[j], owner, i, data))
214 return true;
215 }
216
217 return false;
218}
219
220/* Returns true as soon as fn returns true, otherwise false. */
221bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
222 unsigned int symnum, void *data), void *data)
223{
224 struct module *mod;
225 const struct symsearch arr[] = {
226 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
227 NOT_GPL_ONLY, false },
228 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
229 __start___kcrctab_gpl,
230 GPL_ONLY, false },
231 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
232 __start___kcrctab_gpl_future,
233 WILL_BE_GPL_ONLY, false },
234#ifdef CONFIG_UNUSED_SYMBOLS
235 { __start___ksymtab_unused, __stop___ksymtab_unused,
236 __start___kcrctab_unused,
237 NOT_GPL_ONLY, true },
238 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
239 __start___kcrctab_unused_gpl,
240 GPL_ONLY, true },
241#endif
242 };
243
244 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
245 return true;
246
247 list_for_each_entry_rcu(mod, &modules, list) {
248 struct symsearch arr[] = {
249 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
250 NOT_GPL_ONLY, false },
251 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
252 mod->gpl_crcs,
253 GPL_ONLY, false },
254 { mod->gpl_future_syms,
255 mod->gpl_future_syms + mod->num_gpl_future_syms,
256 mod->gpl_future_crcs,
257 WILL_BE_GPL_ONLY, false },
258#ifdef CONFIG_UNUSED_SYMBOLS
259 { mod->unused_syms,
260 mod->unused_syms + mod->num_unused_syms,
261 mod->unused_crcs,
262 NOT_GPL_ONLY, true },
263 { mod->unused_gpl_syms,
264 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
265 mod->unused_gpl_crcs,
266 GPL_ONLY, true },
267#endif
268 };
269
270 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
271 return true;
272 }
273 return false;
274}
275EXPORT_SYMBOL_GPL(each_symbol);
276
277struct find_symbol_arg {
278 /* Input */
279 const char *name;
280 bool gplok;
281 bool warn;
282
283 /* Output */
284 struct module *owner;
285 const unsigned long *crc;
286 const struct kernel_symbol *sym;
287};
288
289static bool find_symbol_in_section(const struct symsearch *syms,
290 struct module *owner,
291 unsigned int symnum, void *data)
292{
293 struct find_symbol_arg *fsa = data;
294
295 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
296 return false;
297
298 if (!fsa->gplok) {
299 if (syms->licence == GPL_ONLY)
300 return false;
301 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
302 printk(KERN_WARNING "Symbol %s is being used "
303 "by a non-GPL module, which will not "
304 "be allowed in the future\n", fsa->name);
305 printk(KERN_WARNING "Please see the file "
306 "Documentation/feature-removal-schedule.txt "
307 "in the kernel source tree for more details.\n");
308 }
309 }
310
311#ifdef CONFIG_UNUSED_SYMBOLS
312 if (syms->unused && fsa->warn) {
313 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
314 "however this module is using it.\n", fsa->name);
315 printk(KERN_WARNING
316 "This symbol will go away in the future.\n");
317 printk(KERN_WARNING
318 "Please evalute if this is the right api to use and if "
319 "it really is, submit a report the linux kernel "
320 "mailinglist together with submitting your code for "
321 "inclusion.\n");
322 }
323#endif
324
325 fsa->owner = owner;
326 fsa->crc = symversion(syms->crcs, symnum);
327 fsa->sym = &syms->start[symnum];
328 return true;
329}
330
331/* Find a symbol and return it, along with, (optional) crc and
332 * (optional) module which owns it */
333const struct kernel_symbol *find_symbol(const char *name,
334 struct module **owner,
335 const unsigned long **crc,
336 bool gplok,
337 bool warn)
338{
339 struct find_symbol_arg fsa;
340
341 fsa.name = name;
342 fsa.gplok = gplok;
343 fsa.warn = warn;
344
345 if (each_symbol(find_symbol_in_section, &fsa)) {
346 if (owner)
347 *owner = fsa.owner;
348 if (crc)
349 *crc = fsa.crc;
350 return fsa.sym;
351 }
352
353 DEBUGP("Failed to find symbol %s\n", name);
354 return NULL;
355}
356EXPORT_SYMBOL_GPL(find_symbol);
357
358/* Search for module by name: must hold module_mutex. */
359struct module *find_module(const char *name)
360{
361 struct module *mod;
362
363 list_for_each_entry(mod, &modules, list) {
364 if (strcmp(mod->name, name) == 0)
365 return mod;
366 }
367 return NULL;
368}
369EXPORT_SYMBOL_GPL(find_module);
370
371#ifdef CONFIG_SMP
372
373static inline void __percpu *mod_percpu(struct module *mod)
374{
375 return mod->percpu;
376}
377
378static int percpu_modalloc(struct module *mod,
379 unsigned long size, unsigned long align)
380{
381 if (align > PAGE_SIZE) {
382 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
383 mod->name, align, PAGE_SIZE);
384 align = PAGE_SIZE;
385 }
386
387 mod->percpu = __alloc_reserved_percpu(size, align);
388 if (!mod->percpu) {
389 printk(KERN_WARNING
390 "Could not allocate %lu bytes percpu data\n", size);
391 return -ENOMEM;
392 }
393 mod->percpu_size = size;
394 return 0;
395}
396
397static void percpu_modfree(struct module *mod)
398{
399 free_percpu(mod->percpu);
400}
401
402static unsigned int find_pcpusec(Elf_Ehdr *hdr,
403 Elf_Shdr *sechdrs,
404 const char *secstrings)
405{
406 return find_sec(hdr, sechdrs, secstrings, ".data.percpu");
407}
408
409static void percpu_modcopy(struct module *mod,
410 const void *from, unsigned long size)
411{
412 int cpu;
413
414 for_each_possible_cpu(cpu)
415 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
416}
417
418/**
419 * is_module_percpu_address - test whether address is from module static percpu
420 * @addr: address to test
421 *
422 * Test whether @addr belongs to module static percpu area.
423 *
424 * RETURNS:
425 * %true if @addr is from module static percpu area
426 */
427bool is_module_percpu_address(unsigned long addr)
428{
429 struct module *mod;
430 unsigned int cpu;
431
432 preempt_disable();
433
434 list_for_each_entry_rcu(mod, &modules, list) {
435 if (!mod->percpu_size)
436 continue;
437 for_each_possible_cpu(cpu) {
438 void *start = per_cpu_ptr(mod->percpu, cpu);
439
440 if ((void *)addr >= start &&
441 (void *)addr < start + mod->percpu_size) {
442 preempt_enable();
443 return true;
444 }
445 }
446 }
447
448 preempt_enable();
449 return false;
450}
451
452#else /* ... !CONFIG_SMP */
453
454static inline void __percpu *mod_percpu(struct module *mod)
455{
456 return NULL;
457}
458static inline int percpu_modalloc(struct module *mod,
459 unsigned long size, unsigned long align)
460{
461 return -ENOMEM;
462}
463static inline void percpu_modfree(struct module *mod)
464{
465}
466static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
467 Elf_Shdr *sechdrs,
468 const char *secstrings)
469{
470 return 0;
471}
472static inline void percpu_modcopy(struct module *mod,
473 const void *from, unsigned long size)
474{
475 /* pcpusec should be 0, and size of that section should be 0. */
476 BUG_ON(size != 0);
477}
478bool is_module_percpu_address(unsigned long addr)
479{
480 return false;
481}
482
483#endif /* CONFIG_SMP */
484
485#define MODINFO_ATTR(field) \
486static void setup_modinfo_##field(struct module *mod, const char *s) \
487{ \
488 mod->field = kstrdup(s, GFP_KERNEL); \
489} \
490static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
491 struct module *mod, char *buffer) \
492{ \
493 return sprintf(buffer, "%s\n", mod->field); \
494} \
495static int modinfo_##field##_exists(struct module *mod) \
496{ \
497 return mod->field != NULL; \
498} \
499static void free_modinfo_##field(struct module *mod) \
500{ \
501 kfree(mod->field); \
502 mod->field = NULL; \
503} \
504static struct module_attribute modinfo_##field = { \
505 .attr = { .name = __stringify(field), .mode = 0444 }, \
506 .show = show_modinfo_##field, \
507 .setup = setup_modinfo_##field, \
508 .test = modinfo_##field##_exists, \
509 .free = free_modinfo_##field, \
510};
511
512MODINFO_ATTR(version);
513MODINFO_ATTR(srcversion);
514
515static char last_unloaded_module[MODULE_NAME_LEN+1];
516
517#ifdef CONFIG_MODULE_UNLOAD
518/* Init the unload section of the module. */
519static void module_unload_init(struct module *mod)
520{
521 int cpu;
522
523 INIT_LIST_HEAD(&mod->modules_which_use_me);
524 for_each_possible_cpu(cpu) {
525 per_cpu_ptr(mod->refptr, cpu)->incs = 0;
526 per_cpu_ptr(mod->refptr, cpu)->decs = 0;
527 }
528
529 /* Hold reference count during initialization. */
530 __this_cpu_write(mod->refptr->incs, 1);
531 /* Backwards compatibility macros put refcount during init. */
532 mod->waiter = current;
533}
534
535/* modules using other modules */
536struct module_use
537{
538 struct list_head list;
539 struct module *module_which_uses;
540};
541
542/* Does a already use b? */
543static int already_uses(struct module *a, struct module *b)
544{
545 struct module_use *use;
546
547 list_for_each_entry(use, &b->modules_which_use_me, list) {
548 if (use->module_which_uses == a) {
549 DEBUGP("%s uses %s!\n", a->name, b->name);
550 return 1;
551 }
552 }
553 DEBUGP("%s does not use %s!\n", a->name, b->name);
554 return 0;
555}
556
557/* Module a uses b */
558int use_module(struct module *a, struct module *b)
559{
560 struct module_use *use;
561 int no_warn, err;
562
563 if (b == NULL || already_uses(a, b)) return 1;
564
565 /* If we're interrupted or time out, we fail. */
566 if (wait_event_interruptible_timeout(
567 module_wq, (err = strong_try_module_get(b)) != -EBUSY,
568 30 * HZ) <= 0) {
569 printk("%s: gave up waiting for init of module %s.\n",
570 a->name, b->name);
571 return 0;
572 }
573
574 /* If strong_try_module_get() returned a different error, we fail. */
575 if (err)
576 return 0;
577
578 DEBUGP("Allocating new usage for %s.\n", a->name);
579 use = kmalloc(sizeof(*use), GFP_ATOMIC);
580 if (!use) {
581 printk("%s: out of memory loading\n", a->name);
582 module_put(b);
583 return 0;
584 }
585
586 use->module_which_uses = a;
587 list_add(&use->list, &b->modules_which_use_me);
588 no_warn = sysfs_create_link(b->holders_dir, &a->mkobj.kobj, a->name);
589 return 1;
590}
591EXPORT_SYMBOL_GPL(use_module);
592
593/* Clear the unload stuff of the module. */
594static void module_unload_free(struct module *mod)
595{
596 struct module *i;
597
598 list_for_each_entry(i, &modules, list) {
599 struct module_use *use;
600
601 list_for_each_entry(use, &i->modules_which_use_me, list) {
602 if (use->module_which_uses == mod) {
603 DEBUGP("%s unusing %s\n", mod->name, i->name);
604 module_put(i);
605 list_del(&use->list);
606 kfree(use);
607 sysfs_remove_link(i->holders_dir, mod->name);
608 /* There can be at most one match. */
609 break;
610 }
611 }
612 }
613}
614
615#ifdef CONFIG_MODULE_FORCE_UNLOAD
616static inline int try_force_unload(unsigned int flags)
617{
618 int ret = (flags & O_TRUNC);
619 if (ret)
620 add_taint(TAINT_FORCED_RMMOD);
621 return ret;
622}
623#else
624static inline int try_force_unload(unsigned int flags)
625{
626 return 0;
627}
628#endif /* CONFIG_MODULE_FORCE_UNLOAD */
629
630struct stopref
631{
632 struct module *mod;
633 int flags;
634 int *forced;
635};
636
637/* Whole machine is stopped with interrupts off when this runs. */
638static int __try_stop_module(void *_sref)
639{
640 struct stopref *sref = _sref;
641
642 /* If it's not unused, quit unless we're forcing. */
643 if (module_refcount(sref->mod) != 0) {
644 if (!(*sref->forced = try_force_unload(sref->flags)))
645 return -EWOULDBLOCK;
646 }
647
648 /* Mark it as dying. */
649 sref->mod->state = MODULE_STATE_GOING;
650 return 0;
651}
652
653static int try_stop_module(struct module *mod, int flags, int *forced)
654{
655 if (flags & O_NONBLOCK) {
656 struct stopref sref = { mod, flags, forced };
657
658 return stop_machine(__try_stop_module, &sref, NULL);
659 } else {
660 /* We don't need to stop the machine for this. */
661 mod->state = MODULE_STATE_GOING;
662 synchronize_sched();
663 return 0;
664 }
665}
666
667unsigned int module_refcount(struct module *mod)
668{
669 unsigned int incs = 0, decs = 0;
670 int cpu;
671
672 for_each_possible_cpu(cpu)
673 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
674 /*
675 * ensure the incs are added up after the decs.
676 * module_put ensures incs are visible before decs with smp_wmb.
677 *
678 * This 2-count scheme avoids the situation where the refcount
679 * for CPU0 is read, then CPU0 increments the module refcount,
680 * then CPU1 drops that refcount, then the refcount for CPU1 is
681 * read. We would record a decrement but not its corresponding
682 * increment so we would see a low count (disaster).
683 *
684 * Rare situation? But module_refcount can be preempted, and we
685 * might be tallying up 4096+ CPUs. So it is not impossible.
686 */
687 smp_rmb();
688 for_each_possible_cpu(cpu)
689 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
690 return incs - decs;
691}
692EXPORT_SYMBOL(module_refcount);
693
694/* This exists whether we can unload or not */
695static void free_module(struct module *mod);
696
697static void wait_for_zero_refcount(struct module *mod)
698{
699 /* Since we might sleep for some time, release the mutex first */
700 mutex_unlock(&module_mutex);
701 for (;;) {
702 DEBUGP("Looking at refcount...\n");
703 set_current_state(TASK_UNINTERRUPTIBLE);
704 if (module_refcount(mod) == 0)
705 break;
706 schedule();
707 }
708 current->state = TASK_RUNNING;
709 mutex_lock(&module_mutex);
710}
711
712SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
713 unsigned int, flags)
714{
715 struct module *mod;
716 char name[MODULE_NAME_LEN];
717 int ret, forced = 0;
718
719 if (!capable(CAP_SYS_MODULE) || modules_disabled)
720 return -EPERM;
721
722 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
723 return -EFAULT;
724 name[MODULE_NAME_LEN-1] = '\0';
725
726 /* Create stop_machine threads since free_module relies on
727 * a non-failing stop_machine call. */
728 ret = stop_machine_create();
729 if (ret)
730 return ret;
731
732 if (mutex_lock_interruptible(&module_mutex) != 0) {
733 ret = -EINTR;
734 goto out_stop;
735 }
736
737 mod = find_module(name);
738 if (!mod) {
739 ret = -ENOENT;
740 goto out;
741 }
742
743 if (!list_empty(&mod->modules_which_use_me)) {
744 /* Other modules depend on us: get rid of them first. */
745 ret = -EWOULDBLOCK;
746 goto out;
747 }
748
749 /* Doing init or already dying? */
750 if (mod->state != MODULE_STATE_LIVE) {
751 /* FIXME: if (force), slam module count and wake up
752 waiter --RR */
753 DEBUGP("%s already dying\n", mod->name);
754 ret = -EBUSY;
755 goto out;
756 }
757
758 /* If it has an init func, it must have an exit func to unload */
759 if (mod->init && !mod->exit) {
760 forced = try_force_unload(flags);
761 if (!forced) {
762 /* This module can't be removed */
763 ret = -EBUSY;
764 goto out;
765 }
766 }
767
768 /* Set this up before setting mod->state */
769 mod->waiter = current;
770
771 /* Stop the machine so refcounts can't move and disable module. */
772 ret = try_stop_module(mod, flags, &forced);
773 if (ret != 0)
774 goto out;
775
776 /* Never wait if forced. */
777 if (!forced && module_refcount(mod) != 0)
778 wait_for_zero_refcount(mod);
779
780 mutex_unlock(&module_mutex);
781 /* Final destruction now noone is using it. */
782 if (mod->exit != NULL)
783 mod->exit();
784 blocking_notifier_call_chain(&module_notify_list,
785 MODULE_STATE_GOING, mod);
786 async_synchronize_full();
787 mutex_lock(&module_mutex);
788 /* Store the name of the last unloaded module for diagnostic purposes */
789 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
790 ddebug_remove_module(mod->name);
791 free_module(mod);
792
793 out:
794 mutex_unlock(&module_mutex);
795out_stop:
796 stop_machine_destroy();
797 return ret;
798}
799
800static inline void print_unload_info(struct seq_file *m, struct module *mod)
801{
802 struct module_use *use;
803 int printed_something = 0;
804
805 seq_printf(m, " %u ", module_refcount(mod));
806
807 /* Always include a trailing , so userspace can differentiate
808 between this and the old multi-field proc format. */
809 list_for_each_entry(use, &mod->modules_which_use_me, list) {
810 printed_something = 1;
811 seq_printf(m, "%s,", use->module_which_uses->name);
812 }
813
814 if (mod->init != NULL && mod->exit == NULL) {
815 printed_something = 1;
816 seq_printf(m, "[permanent],");
817 }
818
819 if (!printed_something)
820 seq_printf(m, "-");
821}
822
823void __symbol_put(const char *symbol)
824{
825 struct module *owner;
826
827 preempt_disable();
828 if (!find_symbol(symbol, &owner, NULL, true, false))
829 BUG();
830 module_put(owner);
831 preempt_enable();
832}
833EXPORT_SYMBOL(__symbol_put);
834
835/* Note this assumes addr is a function, which it currently always is. */
836void symbol_put_addr(void *addr)
837{
838 struct module *modaddr;
839 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
840
841 if (core_kernel_text(a))
842 return;
843
844 /* module_text_address is safe here: we're supposed to have reference
845 * to module from symbol_get, so it can't go away. */
846 modaddr = __module_text_address(a);
847 BUG_ON(!modaddr);
848 module_put(modaddr);
849}
850EXPORT_SYMBOL_GPL(symbol_put_addr);
851
852static ssize_t show_refcnt(struct module_attribute *mattr,
853 struct module *mod, char *buffer)
854{
855 return sprintf(buffer, "%u\n", module_refcount(mod));
856}
857
858static struct module_attribute refcnt = {
859 .attr = { .name = "refcnt", .mode = 0444 },
860 .show = show_refcnt,
861};
862
863void module_put(struct module *module)
864{
865 if (module) {
866 preempt_disable();
867 smp_wmb(); /* see comment in module_refcount */
868 __this_cpu_inc(module->refptr->decs);
869
870 trace_module_put(module, _RET_IP_,
871 __this_cpu_read(module->refptr->decs));
872 /* Maybe they're waiting for us to drop reference? */
873 if (unlikely(!module_is_live(module)))
874 wake_up_process(module->waiter);
875 preempt_enable();
876 }
877}
878EXPORT_SYMBOL(module_put);
879
880#else /* !CONFIG_MODULE_UNLOAD */
881static inline void print_unload_info(struct seq_file *m, struct module *mod)
882{
883 /* We don't know the usage count, or what modules are using. */
884 seq_printf(m, " - -");
885}
886
887static inline void module_unload_free(struct module *mod)
888{
889}
890
891int use_module(struct module *a, struct module *b)
892{
893 return strong_try_module_get(b) == 0;
894}
895EXPORT_SYMBOL_GPL(use_module);
896
897static inline void module_unload_init(struct module *mod)
898{
899}
900#endif /* CONFIG_MODULE_UNLOAD */
901
902static ssize_t show_initstate(struct module_attribute *mattr,
903 struct module *mod, char *buffer)
904{
905 const char *state = "unknown";
906
907 switch (mod->state) {
908 case MODULE_STATE_LIVE:
909 state = "live";
910 break;
911 case MODULE_STATE_COMING:
912 state = "coming";
913 break;
914 case MODULE_STATE_GOING:
915 state = "going";
916 break;
917 }
918 return sprintf(buffer, "%s\n", state);
919}
920
921static struct module_attribute initstate = {
922 .attr = { .name = "initstate", .mode = 0444 },
923 .show = show_initstate,
924};
925
926static struct module_attribute *modinfo_attrs[] = {
927 &modinfo_version,
928 &modinfo_srcversion,
929 &initstate,
930#ifdef CONFIG_MODULE_UNLOAD
931 &refcnt,
932#endif
933 NULL,
934};
935
936static const char vermagic[] = VERMAGIC_STRING;
937
938static int try_to_force_load(struct module *mod, const char *reason)
939{
940#ifdef CONFIG_MODULE_FORCE_LOAD
941 if (!test_taint(TAINT_FORCED_MODULE))
942 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
943 mod->name, reason);
944 add_taint_module(mod, TAINT_FORCED_MODULE);
945 return 0;
946#else
947 return -ENOEXEC;
948#endif
949}
950
951#ifdef CONFIG_MODVERSIONS
952/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
953static unsigned long maybe_relocated(unsigned long crc,
954 const struct module *crc_owner)
955{
956#ifdef ARCH_RELOCATES_KCRCTAB
957 if (crc_owner == NULL)
958 return crc - (unsigned long)reloc_start;
959#endif
960 return crc;
961}
962
963static int check_version(Elf_Shdr *sechdrs,
964 unsigned int versindex,
965 const char *symname,
966 struct module *mod,
967 const unsigned long *crc,
968 const struct module *crc_owner)
969{
970 unsigned int i, num_versions;
971 struct modversion_info *versions;
972
973 /* Exporting module didn't supply crcs? OK, we're already tainted. */
974 if (!crc)
975 return 1;
976
977 /* No versions at all? modprobe --force does this. */
978 if (versindex == 0)
979 return try_to_force_load(mod, symname) == 0;
980
981 versions = (void *) sechdrs[versindex].sh_addr;
982 num_versions = sechdrs[versindex].sh_size
983 / sizeof(struct modversion_info);
984
985 for (i = 0; i < num_versions; i++) {
986 if (strcmp(versions[i].name, symname) != 0)
987 continue;
988
989 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
990 return 1;
991 DEBUGP("Found checksum %lX vs module %lX\n",
992 maybe_relocated(*crc, crc_owner), versions[i].crc);
993 goto bad_version;
994 }
995
996 printk(KERN_WARNING "%s: no symbol version for %s\n",
997 mod->name, symname);
998 return 0;
999
1000bad_version:
1001 printk("%s: disagrees about version of symbol %s\n",
1002 mod->name, symname);
1003 return 0;
1004}
1005
1006static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1007 unsigned int versindex,
1008 struct module *mod)
1009{
1010 const unsigned long *crc;
1011
1012 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1013 &crc, true, false))
1014 BUG();
1015 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1016 NULL);
1017}
1018
1019/* First part is kernel version, which we ignore if module has crcs. */
1020static inline int same_magic(const char *amagic, const char *bmagic,
1021 bool has_crcs)
1022{
1023 if (has_crcs) {
1024 amagic += strcspn(amagic, " ");
1025 bmagic += strcspn(bmagic, " ");
1026 }
1027 return strcmp(amagic, bmagic) == 0;
1028}
1029#else
1030static inline int check_version(Elf_Shdr *sechdrs,
1031 unsigned int versindex,
1032 const char *symname,
1033 struct module *mod,
1034 const unsigned long *crc,
1035 const struct module *crc_owner)
1036{
1037 return 1;
1038}
1039
1040static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1041 unsigned int versindex,
1042 struct module *mod)
1043{
1044 return 1;
1045}
1046
1047static inline int same_magic(const char *amagic, const char *bmagic,
1048 bool has_crcs)
1049{
1050 return strcmp(amagic, bmagic) == 0;
1051}
1052#endif /* CONFIG_MODVERSIONS */
1053
1054/* Resolve a symbol for this module. I.e. if we find one, record usage.
1055 Must be holding module_mutex. */
1056static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
1057 unsigned int versindex,
1058 const char *name,
1059 struct module *mod)
1060{
1061 struct module *owner;
1062 const struct kernel_symbol *sym;
1063 const unsigned long *crc;
1064
1065 sym = find_symbol(name, &owner, &crc,
1066 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1067 /* use_module can fail due to OOM,
1068 or module initialization or unloading */
1069 if (sym) {
1070 if (!check_version(sechdrs, versindex, name, mod, crc, owner)
1071 || !use_module(mod, owner))
1072 sym = NULL;
1073 }
1074 return sym;
1075}
1076
1077/*
1078 * /sys/module/foo/sections stuff
1079 * J. Corbet <[email protected]>
1080 */
1081#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1082
1083static inline bool sect_empty(const Elf_Shdr *sect)
1084{
1085 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1086}
1087
1088struct module_sect_attr
1089{
1090 struct module_attribute mattr;
1091 char *name;
1092 unsigned long address;
1093};
1094
1095struct module_sect_attrs
1096{
1097 struct attribute_group grp;
1098 unsigned int nsections;
1099 struct module_sect_attr attrs[0];
1100};
1101
1102static ssize_t module_sect_show(struct module_attribute *mattr,
1103 struct module *mod, char *buf)
1104{
1105 struct module_sect_attr *sattr =
1106 container_of(mattr, struct module_sect_attr, mattr);
1107 return sprintf(buf, "0x%lx\n", sattr->address);
1108}
1109
1110static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1111{
1112 unsigned int section;
1113
1114 for (section = 0; section < sect_attrs->nsections; section++)
1115 kfree(sect_attrs->attrs[section].name);
1116 kfree(sect_attrs);
1117}
1118
1119static void add_sect_attrs(struct module *mod, unsigned int nsect,
1120 char *secstrings, Elf_Shdr *sechdrs)
1121{
1122 unsigned int nloaded = 0, i, size[2];
1123 struct module_sect_attrs *sect_attrs;
1124 struct module_sect_attr *sattr;
1125 struct attribute **gattr;
1126
1127 /* Count loaded sections and allocate structures */
1128 for (i = 0; i < nsect; i++)
1129 if (!sect_empty(&sechdrs[i]))
1130 nloaded++;
1131 size[0] = ALIGN(sizeof(*sect_attrs)
1132 + nloaded * sizeof(sect_attrs->attrs[0]),
1133 sizeof(sect_attrs->grp.attrs[0]));
1134 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1135 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1136 if (sect_attrs == NULL)
1137 return;
1138
1139 /* Setup section attributes. */
1140 sect_attrs->grp.name = "sections";
1141 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1142
1143 sect_attrs->nsections = 0;
1144 sattr = &sect_attrs->attrs[0];
1145 gattr = &sect_attrs->grp.attrs[0];
1146 for (i = 0; i < nsect; i++) {
1147 if (sect_empty(&sechdrs[i]))
1148 continue;
1149 sattr->address = sechdrs[i].sh_addr;
1150 sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
1151 GFP_KERNEL);
1152 if (sattr->name == NULL)
1153 goto out;
1154 sect_attrs->nsections++;
1155 sysfs_attr_init(&sattr->mattr.attr);
1156 sattr->mattr.show = module_sect_show;
1157 sattr->mattr.store = NULL;
1158 sattr->mattr.attr.name = sattr->name;
1159 sattr->mattr.attr.mode = S_IRUGO;
1160 *(gattr++) = &(sattr++)->mattr.attr;
1161 }
1162 *gattr = NULL;
1163
1164 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1165 goto out;
1166
1167 mod->sect_attrs = sect_attrs;
1168 return;
1169 out:
1170 free_sect_attrs(sect_attrs);
1171}
1172
1173static void remove_sect_attrs(struct module *mod)
1174{
1175 if (mod->sect_attrs) {
1176 sysfs_remove_group(&mod->mkobj.kobj,
1177 &mod->sect_attrs->grp);
1178 /* We are positive that no one is using any sect attrs
1179 * at this point. Deallocate immediately. */
1180 free_sect_attrs(mod->sect_attrs);
1181 mod->sect_attrs = NULL;
1182 }
1183}
1184
1185/*
1186 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1187 */
1188
1189struct module_notes_attrs {
1190 struct kobject *dir;
1191 unsigned int notes;
1192 struct bin_attribute attrs[0];
1193};
1194
1195static ssize_t module_notes_read(struct kobject *kobj,
1196 struct bin_attribute *bin_attr,
1197 char *buf, loff_t pos, size_t count)
1198{
1199 /*
1200 * The caller checked the pos and count against our size.
1201 */
1202 memcpy(buf, bin_attr->private + pos, count);
1203 return count;
1204}
1205
1206static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1207 unsigned int i)
1208{
1209 if (notes_attrs->dir) {
1210 while (i-- > 0)
1211 sysfs_remove_bin_file(notes_attrs->dir,
1212 &notes_attrs->attrs[i]);
1213 kobject_put(notes_attrs->dir);
1214 }
1215 kfree(notes_attrs);
1216}
1217
1218static void add_notes_attrs(struct module *mod, unsigned int nsect,
1219 char *secstrings, Elf_Shdr *sechdrs)
1220{
1221 unsigned int notes, loaded, i;
1222 struct module_notes_attrs *notes_attrs;
1223 struct bin_attribute *nattr;
1224
1225 /* failed to create section attributes, so can't create notes */
1226 if (!mod->sect_attrs)
1227 return;
1228
1229 /* Count notes sections and allocate structures. */
1230 notes = 0;
1231 for (i = 0; i < nsect; i++)
1232 if (!sect_empty(&sechdrs[i]) &&
1233 (sechdrs[i].sh_type == SHT_NOTE))
1234 ++notes;
1235
1236 if (notes == 0)
1237 return;
1238
1239 notes_attrs = kzalloc(sizeof(*notes_attrs)
1240 + notes * sizeof(notes_attrs->attrs[0]),
1241 GFP_KERNEL);
1242 if (notes_attrs == NULL)
1243 return;
1244
1245 notes_attrs->notes = notes;
1246 nattr = &notes_attrs->attrs[0];
1247 for (loaded = i = 0; i < nsect; ++i) {
1248 if (sect_empty(&sechdrs[i]))
1249 continue;
1250 if (sechdrs[i].sh_type == SHT_NOTE) {
1251 sysfs_bin_attr_init(nattr);
1252 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1253 nattr->attr.mode = S_IRUGO;
1254 nattr->size = sechdrs[i].sh_size;
1255 nattr->private = (void *) sechdrs[i].sh_addr;
1256 nattr->read = module_notes_read;
1257 ++nattr;
1258 }
1259 ++loaded;
1260 }
1261
1262 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1263 if (!notes_attrs->dir)
1264 goto out;
1265
1266 for (i = 0; i < notes; ++i)
1267 if (sysfs_create_bin_file(notes_attrs->dir,
1268 &notes_attrs->attrs[i]))
1269 goto out;
1270
1271 mod->notes_attrs = notes_attrs;
1272 return;
1273
1274 out:
1275 free_notes_attrs(notes_attrs, i);
1276}
1277
1278static void remove_notes_attrs(struct module *mod)
1279{
1280 if (mod->notes_attrs)
1281 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1282}
1283
1284#else
1285
1286static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
1287 char *sectstrings, Elf_Shdr *sechdrs)
1288{
1289}
1290
1291static inline void remove_sect_attrs(struct module *mod)
1292{
1293}
1294
1295static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
1296 char *sectstrings, Elf_Shdr *sechdrs)
1297{
1298}
1299
1300static inline void remove_notes_attrs(struct module *mod)
1301{
1302}
1303#endif
1304
1305#ifdef CONFIG_SYSFS
1306int module_add_modinfo_attrs(struct module *mod)
1307{
1308 struct module_attribute *attr;
1309 struct module_attribute *temp_attr;
1310 int error = 0;
1311 int i;
1312
1313 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1314 (ARRAY_SIZE(modinfo_attrs) + 1)),
1315 GFP_KERNEL);
1316 if (!mod->modinfo_attrs)
1317 return -ENOMEM;
1318
1319 temp_attr = mod->modinfo_attrs;
1320 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1321 if (!attr->test ||
1322 (attr->test && attr->test(mod))) {
1323 memcpy(temp_attr, attr, sizeof(*temp_attr));
1324 sysfs_attr_init(&temp_attr->attr);
1325 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1326 ++temp_attr;
1327 }
1328 }
1329 return error;
1330}
1331
1332void module_remove_modinfo_attrs(struct module *mod)
1333{
1334 struct module_attribute *attr;
1335 int i;
1336
1337 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1338 /* pick a field to test for end of list */
1339 if (!attr->attr.name)
1340 break;
1341 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1342 if (attr->free)
1343 attr->free(mod);
1344 }
1345 kfree(mod->modinfo_attrs);
1346}
1347
1348int mod_sysfs_init(struct module *mod)
1349{
1350 int err;
1351 struct kobject *kobj;
1352
1353 if (!module_sysfs_initialized) {
1354 printk(KERN_ERR "%s: module sysfs not initialized\n",
1355 mod->name);
1356 err = -EINVAL;
1357 goto out;
1358 }
1359
1360 kobj = kset_find_obj(module_kset, mod->name);
1361 if (kobj) {
1362 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1363 kobject_put(kobj);
1364 err = -EINVAL;
1365 goto out;
1366 }
1367
1368 mod->mkobj.mod = mod;
1369
1370 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1371 mod->mkobj.kobj.kset = module_kset;
1372 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1373 "%s", mod->name);
1374 if (err)
1375 kobject_put(&mod->mkobj.kobj);
1376
1377 /* delay uevent until full sysfs population */
1378out:
1379 return err;
1380}
1381
1382int mod_sysfs_setup(struct module *mod,
1383 struct kernel_param *kparam,
1384 unsigned int num_params)
1385{
1386 int err;
1387
1388 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1389 if (!mod->holders_dir) {
1390 err = -ENOMEM;
1391 goto out_unreg;
1392 }
1393
1394 err = module_param_sysfs_setup(mod, kparam, num_params);
1395 if (err)
1396 goto out_unreg_holders;
1397
1398 err = module_add_modinfo_attrs(mod);
1399 if (err)
1400 goto out_unreg_param;
1401
1402 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1403 return 0;
1404
1405out_unreg_param:
1406 module_param_sysfs_remove(mod);
1407out_unreg_holders:
1408 kobject_put(mod->holders_dir);
1409out_unreg:
1410 kobject_put(&mod->mkobj.kobj);
1411 return err;
1412}
1413
1414static void mod_sysfs_fini(struct module *mod)
1415{
1416 kobject_put(&mod->mkobj.kobj);
1417}
1418
1419#else /* CONFIG_SYSFS */
1420
1421static void mod_sysfs_fini(struct module *mod)
1422{
1423}
1424
1425#endif /* CONFIG_SYSFS */
1426
1427static void mod_kobject_remove(struct module *mod)
1428{
1429 module_remove_modinfo_attrs(mod);
1430 module_param_sysfs_remove(mod);
1431 kobject_put(mod->mkobj.drivers_dir);
1432 kobject_put(mod->holders_dir);
1433 mod_sysfs_fini(mod);
1434}
1435
1436/*
1437 * unlink the module with the whole machine is stopped with interrupts off
1438 * - this defends against kallsyms not taking locks
1439 */
1440static int __unlink_module(void *_mod)
1441{
1442 struct module *mod = _mod;
1443 list_del(&mod->list);
1444 return 0;
1445}
1446
1447/* Free a module, remove from lists, etc (must hold module_mutex). */
1448static void free_module(struct module *mod)
1449{
1450 trace_module_free(mod);
1451
1452 /* Delete from various lists */
1453 stop_machine(__unlink_module, mod, NULL);
1454 remove_notes_attrs(mod);
1455 remove_sect_attrs(mod);
1456 mod_kobject_remove(mod);
1457
1458 /* Arch-specific cleanup. */
1459 module_arch_cleanup(mod);
1460
1461 /* Module unload stuff */
1462 module_unload_free(mod);
1463
1464 /* Free any allocated parameters. */
1465 destroy_params(mod->kp, mod->num_kp);
1466
1467 /* This may be NULL, but that's OK */
1468 module_free(mod, mod->module_init);
1469 kfree(mod->args);
1470 percpu_modfree(mod);
1471#if defined(CONFIG_MODULE_UNLOAD)
1472 if (mod->refptr)
1473 free_percpu(mod->refptr);
1474#endif
1475 /* Free lock-classes: */
1476 lockdep_free_key_range(mod->module_core, mod->core_size);
1477
1478 /* Finally, free the core (containing the module structure) */
1479 module_free(mod, mod->module_core);
1480
1481#ifdef CONFIG_MPU
1482 update_protections(current->mm);
1483#endif
1484}
1485
1486void *__symbol_get(const char *symbol)
1487{
1488 struct module *owner;
1489 const struct kernel_symbol *sym;
1490
1491 preempt_disable();
1492 sym = find_symbol(symbol, &owner, NULL, true, true);
1493 if (sym && strong_try_module_get(owner))
1494 sym = NULL;
1495 preempt_enable();
1496
1497 return sym ? (void *)sym->value : NULL;
1498}
1499EXPORT_SYMBOL_GPL(__symbol_get);
1500
1501/*
1502 * Ensure that an exported symbol [global namespace] does not already exist
1503 * in the kernel or in some other module's exported symbol table.
1504 */
1505static int verify_export_symbols(struct module *mod)
1506{
1507 unsigned int i;
1508 struct module *owner;
1509 const struct kernel_symbol *s;
1510 struct {
1511 const struct kernel_symbol *sym;
1512 unsigned int num;
1513 } arr[] = {
1514 { mod->syms, mod->num_syms },
1515 { mod->gpl_syms, mod->num_gpl_syms },
1516 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1517#ifdef CONFIG_UNUSED_SYMBOLS
1518 { mod->unused_syms, mod->num_unused_syms },
1519 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1520#endif
1521 };
1522
1523 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1524 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1525 if (find_symbol(s->name, &owner, NULL, true, false)) {
1526 printk(KERN_ERR
1527 "%s: exports duplicate symbol %s"
1528 " (owned by %s)\n",
1529 mod->name, s->name, module_name(owner));
1530 return -ENOEXEC;
1531 }
1532 }
1533 }
1534 return 0;
1535}
1536
1537/* Change all symbols so that st_value encodes the pointer directly. */
1538static int simplify_symbols(Elf_Shdr *sechdrs,
1539 unsigned int symindex,
1540 const char *strtab,
1541 unsigned int versindex,
1542 unsigned int pcpuindex,
1543 struct module *mod)
1544{
1545 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1546 unsigned long secbase;
1547 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1548 int ret = 0;
1549 const struct kernel_symbol *ksym;
1550
1551 for (i = 1; i < n; i++) {
1552 switch (sym[i].st_shndx) {
1553 case SHN_COMMON:
1554 /* We compiled with -fno-common. These are not
1555 supposed to happen. */
1556 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1557 printk("%s: please compile with -fno-common\n",
1558 mod->name);
1559 ret = -ENOEXEC;
1560 break;
1561
1562 case SHN_ABS:
1563 /* Don't need to do anything */
1564 DEBUGP("Absolute symbol: 0x%08lx\n",
1565 (long)sym[i].st_value);
1566 break;
1567
1568 case SHN_UNDEF:
1569 ksym = resolve_symbol(sechdrs, versindex,
1570 strtab + sym[i].st_name, mod);
1571 /* Ok if resolved. */
1572 if (ksym) {
1573 sym[i].st_value = ksym->value;
1574 break;
1575 }
1576
1577 /* Ok if weak. */
1578 if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1579 break;
1580
1581 printk(KERN_WARNING "%s: Unknown symbol %s\n",
1582 mod->name, strtab + sym[i].st_name);
1583 ret = -ENOENT;
1584 break;
1585
1586 default:
1587 /* Divert to percpu allocation if a percpu var. */
1588 if (sym[i].st_shndx == pcpuindex)
1589 secbase = (unsigned long)mod_percpu(mod);
1590 else
1591 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1592 sym[i].st_value += secbase;
1593 break;
1594 }
1595 }
1596
1597 return ret;
1598}
1599
1600/* Additional bytes needed by arch in front of individual sections */
1601unsigned int __weak arch_mod_section_prepend(struct module *mod,
1602 unsigned int section)
1603{
1604 /* default implementation just returns zero */
1605 return 0;
1606}
1607
1608/* Update size with this section: return offset. */
1609static long get_offset(struct module *mod, unsigned int *size,
1610 Elf_Shdr *sechdr, unsigned int section)
1611{
1612 long ret;
1613
1614 *size += arch_mod_section_prepend(mod, section);
1615 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1616 *size = ret + sechdr->sh_size;
1617 return ret;
1618}
1619
1620/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1621 might -- code, read-only data, read-write data, small data. Tally
1622 sizes, and place the offsets into sh_entsize fields: high bit means it
1623 belongs in init. */
1624static void layout_sections(struct module *mod,
1625 const Elf_Ehdr *hdr,
1626 Elf_Shdr *sechdrs,
1627 const char *secstrings)
1628{
1629 static unsigned long const masks[][2] = {
1630 /* NOTE: all executable code must be the first section
1631 * in this array; otherwise modify the text_size
1632 * finder in the two loops below */
1633 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1634 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1635 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1636 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1637 };
1638 unsigned int m, i;
1639
1640 for (i = 0; i < hdr->e_shnum; i++)
1641 sechdrs[i].sh_entsize = ~0UL;
1642
1643 DEBUGP("Core section allocation order:\n");
1644 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1645 for (i = 0; i < hdr->e_shnum; ++i) {
1646 Elf_Shdr *s = &sechdrs[i];
1647
1648 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1649 || (s->sh_flags & masks[m][1])
1650 || s->sh_entsize != ~0UL
1651 || strstarts(secstrings + s->sh_name, ".init"))
1652 continue;
1653 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1654 DEBUGP("\t%s\n", secstrings + s->sh_name);
1655 }
1656 if (m == 0)
1657 mod->core_text_size = mod->core_size;
1658 }
1659
1660 DEBUGP("Init section allocation order:\n");
1661 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1662 for (i = 0; i < hdr->e_shnum; ++i) {
1663 Elf_Shdr *s = &sechdrs[i];
1664
1665 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1666 || (s->sh_flags & masks[m][1])
1667 || s->sh_entsize != ~0UL
1668 || !strstarts(secstrings + s->sh_name, ".init"))
1669 continue;
1670 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1671 | INIT_OFFSET_MASK);
1672 DEBUGP("\t%s\n", secstrings + s->sh_name);
1673 }
1674 if (m == 0)
1675 mod->init_text_size = mod->init_size;
1676 }
1677}
1678
1679static void set_license(struct module *mod, const char *license)
1680{
1681 if (!license)
1682 license = "unspecified";
1683
1684 if (!license_is_gpl_compatible(license)) {
1685 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1686 printk(KERN_WARNING "%s: module license '%s' taints "
1687 "kernel.\n", mod->name, license);
1688 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1689 }
1690}
1691
1692/* Parse tag=value strings from .modinfo section */
1693static char *next_string(char *string, unsigned long *secsize)
1694{
1695 /* Skip non-zero chars */
1696 while (string[0]) {
1697 string++;
1698 if ((*secsize)-- <= 1)
1699 return NULL;
1700 }
1701
1702 /* Skip any zero padding. */
1703 while (!string[0]) {
1704 string++;
1705 if ((*secsize)-- <= 1)
1706 return NULL;
1707 }
1708 return string;
1709}
1710
1711static char *get_modinfo(Elf_Shdr *sechdrs,
1712 unsigned int info,
1713 const char *tag)
1714{
1715 char *p;
1716 unsigned int taglen = strlen(tag);
1717 unsigned long size = sechdrs[info].sh_size;
1718
1719 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1720 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1721 return p + taglen + 1;
1722 }
1723 return NULL;
1724}
1725
1726static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1727 unsigned int infoindex)
1728{
1729 struct module_attribute *attr;
1730 int i;
1731
1732 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1733 if (attr->setup)
1734 attr->setup(mod,
1735 get_modinfo(sechdrs,
1736 infoindex,
1737 attr->attr.name));
1738 }
1739}
1740
1741static void free_modinfo(struct module *mod)
1742{
1743 struct module_attribute *attr;
1744 int i;
1745
1746 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1747 if (attr->free)
1748 attr->free(mod);
1749 }
1750}
1751
1752#ifdef CONFIG_KALLSYMS
1753
1754/* lookup symbol in given range of kernel_symbols */
1755static const struct kernel_symbol *lookup_symbol(const char *name,
1756 const struct kernel_symbol *start,
1757 const struct kernel_symbol *stop)
1758{
1759 const struct kernel_symbol *ks = start;
1760 for (; ks < stop; ks++)
1761 if (strcmp(ks->name, name) == 0)
1762 return ks;
1763 return NULL;
1764}
1765
1766static int is_exported(const char *name, unsigned long value,
1767 const struct module *mod)
1768{
1769 const struct kernel_symbol *ks;
1770 if (!mod)
1771 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1772 else
1773 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1774 return ks != NULL && ks->value == value;
1775}
1776
1777/* As per nm */
1778static char elf_type(const Elf_Sym *sym,
1779 Elf_Shdr *sechdrs,
1780 const char *secstrings,
1781 struct module *mod)
1782{
1783 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1784 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1785 return 'v';
1786 else
1787 return 'w';
1788 }
1789 if (sym->st_shndx == SHN_UNDEF)
1790 return 'U';
1791 if (sym->st_shndx == SHN_ABS)
1792 return 'a';
1793 if (sym->st_shndx >= SHN_LORESERVE)
1794 return '?';
1795 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1796 return 't';
1797 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1798 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1799 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1800 return 'r';
1801 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1802 return 'g';
1803 else
1804 return 'd';
1805 }
1806 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1807 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1808 return 's';
1809 else
1810 return 'b';
1811 }
1812 if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug"))
1813 return 'n';
1814 return '?';
1815}
1816
1817static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1818 unsigned int shnum)
1819{
1820 const Elf_Shdr *sec;
1821
1822 if (src->st_shndx == SHN_UNDEF
1823 || src->st_shndx >= shnum
1824 || !src->st_name)
1825 return false;
1826
1827 sec = sechdrs + src->st_shndx;
1828 if (!(sec->sh_flags & SHF_ALLOC)
1829#ifndef CONFIG_KALLSYMS_ALL
1830 || !(sec->sh_flags & SHF_EXECINSTR)
1831#endif
1832 || (sec->sh_entsize & INIT_OFFSET_MASK))
1833 return false;
1834
1835 return true;
1836}
1837
1838static unsigned long layout_symtab(struct module *mod,
1839 Elf_Shdr *sechdrs,
1840 unsigned int symindex,
1841 unsigned int strindex,
1842 const Elf_Ehdr *hdr,
1843 const char *secstrings,
1844 unsigned long *pstroffs,
1845 unsigned long *strmap)
1846{
1847 unsigned long symoffs;
1848 Elf_Shdr *symsect = sechdrs + symindex;
1849 Elf_Shdr *strsect = sechdrs + strindex;
1850 const Elf_Sym *src;
1851 const char *strtab;
1852 unsigned int i, nsrc, ndst;
1853
1854 /* Put symbol section at end of init part of module. */
1855 symsect->sh_flags |= SHF_ALLOC;
1856 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1857 symindex) | INIT_OFFSET_MASK;
1858 DEBUGP("\t%s\n", secstrings + symsect->sh_name);
1859
1860 src = (void *)hdr + symsect->sh_offset;
1861 nsrc = symsect->sh_size / sizeof(*src);
1862 strtab = (void *)hdr + strsect->sh_offset;
1863 for (ndst = i = 1; i < nsrc; ++i, ++src)
1864 if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
1865 unsigned int j = src->st_name;
1866
1867 while(!__test_and_set_bit(j, strmap) && strtab[j])
1868 ++j;
1869 ++ndst;
1870 }
1871
1872 /* Append room for core symbols at end of core part. */
1873 symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
1874 mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
1875
1876 /* Put string table section at end of init part of module. */
1877 strsect->sh_flags |= SHF_ALLOC;
1878 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
1879 strindex) | INIT_OFFSET_MASK;
1880 DEBUGP("\t%s\n", secstrings + strsect->sh_name);
1881
1882 /* Append room for core symbols' strings at end of core part. */
1883 *pstroffs = mod->core_size;
1884 __set_bit(0, strmap);
1885 mod->core_size += bitmap_weight(strmap, strsect->sh_size);
1886
1887 return symoffs;
1888}
1889
1890static void add_kallsyms(struct module *mod,
1891 Elf_Shdr *sechdrs,
1892 unsigned int shnum,
1893 unsigned int symindex,
1894 unsigned int strindex,
1895 unsigned long symoffs,
1896 unsigned long stroffs,
1897 const char *secstrings,
1898 unsigned long *strmap)
1899{
1900 unsigned int i, ndst;
1901 const Elf_Sym *src;
1902 Elf_Sym *dst;
1903 char *s;
1904
1905 mod->symtab = (void *)sechdrs[symindex].sh_addr;
1906 mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1907 mod->strtab = (void *)sechdrs[strindex].sh_addr;
1908
1909 /* Set types up while we still have access to sections. */
1910 for (i = 0; i < mod->num_symtab; i++)
1911 mod->symtab[i].st_info
1912 = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
1913
1914 mod->core_symtab = dst = mod->module_core + symoffs;
1915 src = mod->symtab;
1916 *dst = *src;
1917 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
1918 if (!is_core_symbol(src, sechdrs, shnum))
1919 continue;
1920 dst[ndst] = *src;
1921 dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
1922 ++ndst;
1923 }
1924 mod->core_num_syms = ndst;
1925
1926 mod->core_strtab = s = mod->module_core + stroffs;
1927 for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i)
1928 if (test_bit(i, strmap))
1929 *++s = mod->strtab[i];
1930}
1931#else
1932static inline unsigned long layout_symtab(struct module *mod,
1933 Elf_Shdr *sechdrs,
1934 unsigned int symindex,
1935 unsigned int strindex,
1936 const Elf_Ehdr *hdr,
1937 const char *secstrings,
1938 unsigned long *pstroffs,
1939 unsigned long *strmap)
1940{
1941 return 0;
1942}
1943
1944static inline void add_kallsyms(struct module *mod,
1945 Elf_Shdr *sechdrs,
1946 unsigned int shnum,
1947 unsigned int symindex,
1948 unsigned int strindex,
1949 unsigned long symoffs,
1950 unsigned long stroffs,
1951 const char *secstrings,
1952 const unsigned long *strmap)
1953{
1954}
1955#endif /* CONFIG_KALLSYMS */
1956
1957static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
1958{
1959#ifdef CONFIG_DYNAMIC_DEBUG
1960 if (ddebug_add_module(debug, num, debug->modname))
1961 printk(KERN_ERR "dynamic debug error adding module: %s\n",
1962 debug->modname);
1963#endif
1964}
1965
1966static void *module_alloc_update_bounds(unsigned long size)
1967{
1968 void *ret = module_alloc(size);
1969
1970 if (ret) {
1971 /* Update module bounds. */
1972 if ((unsigned long)ret < module_addr_min)
1973 module_addr_min = (unsigned long)ret;
1974 if ((unsigned long)ret + size > module_addr_max)
1975 module_addr_max = (unsigned long)ret + size;
1976 }
1977 return ret;
1978}
1979
1980#ifdef CONFIG_DEBUG_KMEMLEAK
1981static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
1982 Elf_Shdr *sechdrs, char *secstrings)
1983{
1984 unsigned int i;
1985
1986 /* only scan the sections containing data */
1987 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
1988
1989 for (i = 1; i < hdr->e_shnum; i++) {
1990 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
1991 continue;
1992 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
1993 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
1994 continue;
1995
1996 kmemleak_scan_area((void *)sechdrs[i].sh_addr,
1997 sechdrs[i].sh_size, GFP_KERNEL);
1998 }
1999}
2000#else
2001static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2002 Elf_Shdr *sechdrs, char *secstrings)
2003{
2004}
2005#endif
2006
2007/* Allocate and load the module: note that size of section 0 is always
2008 zero, and we rely on this for optional sections. */
2009static noinline struct module *load_module(void __user *umod,
2010 unsigned long len,
2011 const char __user *uargs)
2012{
2013 Elf_Ehdr *hdr;
2014 Elf_Shdr *sechdrs;
2015 char *secstrings, *args, *modmagic, *strtab = NULL;
2016 char *staging;
2017 unsigned int i;
2018 unsigned int symindex = 0;
2019 unsigned int strindex = 0;
2020 unsigned int modindex, versindex, infoindex, pcpuindex;
2021 struct module *mod;
2022 long err = 0;
2023 void *ptr = NULL; /* Stops spurious gcc warning */
2024 unsigned long symoffs, stroffs, *strmap;
2025
2026 mm_segment_t old_fs;
2027
2028 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2029 umod, len, uargs);
2030 if (len < sizeof(*hdr))
2031 return ERR_PTR(-ENOEXEC);
2032
2033 /* Suck in entire file: we'll want most of it. */
2034 /* vmalloc barfs on "unusual" numbers. Check here */
2035 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
2036 return ERR_PTR(-ENOMEM);
2037
2038 if (copy_from_user(hdr, umod, len) != 0) {
2039 err = -EFAULT;
2040 goto free_hdr;
2041 }
2042
2043 /* Sanity checks against insmoding binaries or wrong arch,
2044 weird elf version */
2045 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
2046 || hdr->e_type != ET_REL
2047 || !elf_check_arch(hdr)
2048 || hdr->e_shentsize != sizeof(*sechdrs)) {
2049 err = -ENOEXEC;
2050 goto free_hdr;
2051 }
2052
2053 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
2054 goto truncated;
2055
2056 /* Convenience variables */
2057 sechdrs = (void *)hdr + hdr->e_shoff;
2058 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
2059 sechdrs[0].sh_addr = 0;
2060
2061 for (i = 1; i < hdr->e_shnum; i++) {
2062 if (sechdrs[i].sh_type != SHT_NOBITS
2063 && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
2064 goto truncated;
2065
2066 /* Mark all sections sh_addr with their address in the
2067 temporary image. */
2068 sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;
2069
2070 /* Internal symbols and strings. */
2071 if (sechdrs[i].sh_type == SHT_SYMTAB) {
2072 symindex = i;
2073 strindex = sechdrs[i].sh_link;
2074 strtab = (char *)hdr + sechdrs[strindex].sh_offset;
2075 }
2076#ifndef CONFIG_MODULE_UNLOAD
2077 /* Don't load .exit sections */
2078 if (strstarts(secstrings+sechdrs[i].sh_name, ".exit"))
2079 sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
2080#endif
2081 }
2082
2083 modindex = find_sec(hdr, sechdrs, secstrings,
2084 ".gnu.linkonce.this_module");
2085 if (!modindex) {
2086 printk(KERN_WARNING "No module found in object\n");
2087 err = -ENOEXEC;
2088 goto free_hdr;
2089 }
2090 /* This is temporary: point mod into copy of data. */
2091 mod = (void *)sechdrs[modindex].sh_addr;
2092
2093 if (symindex == 0) {
2094 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2095 mod->name);
2096 err = -ENOEXEC;
2097 goto free_hdr;
2098 }
2099
2100 versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
2101 infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
2102 pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
2103
2104 /* Don't keep modinfo and version sections. */
2105 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2106 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2107
2108 /* Check module struct version now, before we try to use module. */
2109 if (!check_modstruct_version(sechdrs, versindex, mod)) {
2110 err = -ENOEXEC;
2111 goto free_hdr;
2112 }
2113
2114 modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2115 /* This is allowed: modprobe --force will invalidate it. */
2116 if (!modmagic) {
2117 err = try_to_force_load(mod, "bad vermagic");
2118 if (err)
2119 goto free_hdr;
2120 } else if (!same_magic(modmagic, vermagic, versindex)) {
2121 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2122 mod->name, modmagic, vermagic);
2123 err = -ENOEXEC;
2124 goto free_hdr;
2125 }
2126
2127 staging = get_modinfo(sechdrs, infoindex, "staging");
2128 if (staging) {
2129 add_taint_module(mod, TAINT_CRAP);
2130 printk(KERN_WARNING "%s: module is from the staging directory,"
2131 " the quality is unknown, you have been warned.\n",
2132 mod->name);
2133 }
2134
2135 /* Now copy in args */
2136 args = strndup_user(uargs, ~0UL >> 1);
2137 if (IS_ERR(args)) {
2138 err = PTR_ERR(args);
2139 goto free_hdr;
2140 }
2141
2142 strmap = kzalloc(BITS_TO_LONGS(sechdrs[strindex].sh_size)
2143 * sizeof(long), GFP_KERNEL);
2144 if (!strmap) {
2145 err = -ENOMEM;
2146 goto free_mod;
2147 }
2148
2149 if (find_module(mod->name)) {
2150 err = -EEXIST;
2151 goto free_mod;
2152 }
2153
2154 mod->state = MODULE_STATE_COMING;
2155
2156 /* Allow arches to frob section contents and sizes. */
2157 err = module_frob_arch_sections(hdr, sechdrs, secstrings, mod);
2158 if (err < 0)
2159 goto free_mod;
2160
2161 if (pcpuindex) {
2162 /* We have a special allocation for this section. */
2163 err = percpu_modalloc(mod, sechdrs[pcpuindex].sh_size,
2164 sechdrs[pcpuindex].sh_addralign);
2165 if (err)
2166 goto free_mod;
2167 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
2168 }
2169
2170 /* Determine total sizes, and put offsets in sh_entsize. For now
2171 this is done generically; there doesn't appear to be any
2172 special cases for the architectures. */
2173 layout_sections(mod, hdr, sechdrs, secstrings);
2174 symoffs = layout_symtab(mod, sechdrs, symindex, strindex, hdr,
2175 secstrings, &stroffs, strmap);
2176
2177 /* Do the allocs. */
2178 ptr = module_alloc_update_bounds(mod->core_size);
2179 /*
2180 * The pointer to this block is stored in the module structure
2181 * which is inside the block. Just mark it as not being a
2182 * leak.
2183 */
2184 kmemleak_not_leak(ptr);
2185 if (!ptr) {
2186 err = -ENOMEM;
2187 goto free_percpu;
2188 }
2189 memset(ptr, 0, mod->core_size);
2190 mod->module_core = ptr;
2191
2192 ptr = module_alloc_update_bounds(mod->init_size);
2193 /*
2194 * The pointer to this block is stored in the module structure
2195 * which is inside the block. This block doesn't need to be
2196 * scanned as it contains data and code that will be freed
2197 * after the module is initialized.
2198 */
2199 kmemleak_ignore(ptr);
2200 if (!ptr && mod->init_size) {
2201 err = -ENOMEM;
2202 goto free_core;
2203 }
2204 memset(ptr, 0, mod->init_size);
2205 mod->module_init = ptr;
2206
2207 /* Transfer each section which specifies SHF_ALLOC */
2208 DEBUGP("final section addresses:\n");
2209 for (i = 0; i < hdr->e_shnum; i++) {
2210 void *dest;
2211
2212 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2213 continue;
2214
2215 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2216 dest = mod->module_init
2217 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2218 else
2219 dest = mod->module_core + sechdrs[i].sh_entsize;
2220
2221 if (sechdrs[i].sh_type != SHT_NOBITS)
2222 memcpy(dest, (void *)sechdrs[i].sh_addr,
2223 sechdrs[i].sh_size);
2224 /* Update sh_addr to point to copy in image. */
2225 sechdrs[i].sh_addr = (unsigned long)dest;
2226 DEBUGP("\t0x%lx %s\n", sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2227 }
2228 /* Module has been moved. */
2229 mod = (void *)sechdrs[modindex].sh_addr;
2230 kmemleak_load_module(mod, hdr, sechdrs, secstrings);
2231
2232#if defined(CONFIG_MODULE_UNLOAD)
2233 mod->refptr = alloc_percpu(struct module_ref);
2234 if (!mod->refptr) {
2235 err = -ENOMEM;
2236 goto free_init;
2237 }
2238#endif
2239 /* Now we've moved module, initialize linked lists, etc. */
2240 module_unload_init(mod);
2241
2242 /* add kobject, so we can reference it. */
2243 err = mod_sysfs_init(mod);
2244 if (err)
2245 goto free_unload;
2246
2247 /* Set up license info based on the info section */
2248 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2249
2250 /*
2251 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2252 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2253 * using GPL-only symbols it needs.
2254 */
2255 if (strcmp(mod->name, "ndiswrapper") == 0)
2256 add_taint(TAINT_PROPRIETARY_MODULE);
2257
2258 /* driverloader was caught wrongly pretending to be under GPL */
2259 if (strcmp(mod->name, "driverloader") == 0)
2260 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2261
2262 /* Set up MODINFO_ATTR fields */
2263 setup_modinfo(mod, sechdrs, infoindex);
2264
2265 /* Fix up syms, so that st_value is a pointer to location. */
2266 err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
2267 mod);
2268 if (err < 0)
2269 goto cleanup;
2270
2271 /* Now we've got everything in the final locations, we can
2272 * find optional sections. */
2273 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2274 sizeof(*mod->kp), &mod->num_kp);
2275 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2276 sizeof(*mod->syms), &mod->num_syms);
2277 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2278 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2279 sizeof(*mod->gpl_syms),
2280 &mod->num_gpl_syms);
2281 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2282 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2283 "__ksymtab_gpl_future",
2284 sizeof(*mod->gpl_future_syms),
2285 &mod->num_gpl_future_syms);
2286 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2287 "__kcrctab_gpl_future");
2288
2289#ifdef CONFIG_UNUSED_SYMBOLS
2290 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2291 "__ksymtab_unused",
2292 sizeof(*mod->unused_syms),
2293 &mod->num_unused_syms);
2294 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2295 "__kcrctab_unused");
2296 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2297 "__ksymtab_unused_gpl",
2298 sizeof(*mod->unused_gpl_syms),
2299 &mod->num_unused_gpl_syms);
2300 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2301 "__kcrctab_unused_gpl");
2302#endif
2303#ifdef CONFIG_CONSTRUCTORS
2304 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2305 sizeof(*mod->ctors), &mod->num_ctors);
2306#endif
2307
2308#ifdef CONFIG_TRACEPOINTS
2309 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2310 "__tracepoints",
2311 sizeof(*mod->tracepoints),
2312 &mod->num_tracepoints);
2313#endif
2314#ifdef CONFIG_EVENT_TRACING
2315 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2316 "_ftrace_events",
2317 sizeof(*mod->trace_events),
2318 &mod->num_trace_events);
2319 /*
2320 * This section contains pointers to allocated objects in the trace
2321 * code and not scanning it leads to false positives.
2322 */
2323 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2324 mod->num_trace_events, GFP_KERNEL);
2325#endif
2326#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2327 /* sechdrs[0].sh_size is always zero */
2328 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2329 "__mcount_loc",
2330 sizeof(*mod->ftrace_callsites),
2331 &mod->num_ftrace_callsites);
2332#endif
2333#ifdef CONFIG_MODVERSIONS
2334 if ((mod->num_syms && !mod->crcs)
2335 || (mod->num_gpl_syms && !mod->gpl_crcs)
2336 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2337#ifdef CONFIG_UNUSED_SYMBOLS
2338 || (mod->num_unused_syms && !mod->unused_crcs)
2339 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2340#endif
2341 ) {
2342 err = try_to_force_load(mod,
2343 "no versions for exported symbols");
2344 if (err)
2345 goto cleanup;
2346 }
2347#endif
2348
2349 /* Now do relocations. */
2350 for (i = 1; i < hdr->e_shnum; i++) {
2351 const char *strtab = (char *)sechdrs[strindex].sh_addr;
2352 unsigned int info = sechdrs[i].sh_info;
2353
2354 /* Not a valid relocation section? */
2355 if (info >= hdr->e_shnum)
2356 continue;
2357
2358 /* Don't bother with non-allocated sections */
2359 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
2360 continue;
2361
2362 if (sechdrs[i].sh_type == SHT_REL)
2363 err = apply_relocate(sechdrs, strtab, symindex, i,mod);
2364 else if (sechdrs[i].sh_type == SHT_RELA)
2365 err = apply_relocate_add(sechdrs, strtab, symindex, i,
2366 mod);
2367 if (err < 0)
2368 goto cleanup;
2369 }
2370
2371 /* Find duplicate symbols */
2372 err = verify_export_symbols(mod);
2373 if (err < 0)
2374 goto cleanup;
2375
2376 /* Set up and sort exception table */
2377 mod->extable = section_objs(hdr, sechdrs, secstrings, "__ex_table",
2378 sizeof(*mod->extable), &mod->num_exentries);
2379 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2380
2381 /* Finally, copy percpu area over. */
2382 percpu_modcopy(mod, (void *)sechdrs[pcpuindex].sh_addr,
2383 sechdrs[pcpuindex].sh_size);
2384
2385 add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex,
2386 symoffs, stroffs, secstrings, strmap);
2387 kfree(strmap);
2388 strmap = NULL;
2389
2390 if (!mod->taints) {
2391 struct _ddebug *debug;
2392 unsigned int num_debug;
2393
2394 debug = section_objs(hdr, sechdrs, secstrings, "__verbose",
2395 sizeof(*debug), &num_debug);
2396 if (debug)
2397 dynamic_debug_setup(debug, num_debug);
2398 }
2399
2400 err = module_finalize(hdr, sechdrs, mod);
2401 if (err < 0)
2402 goto cleanup;
2403
2404 /* flush the icache in correct context */
2405 old_fs = get_fs();
2406 set_fs(KERNEL_DS);
2407
2408 /*
2409 * Flush the instruction cache, since we've played with text.
2410 * Do it before processing of module parameters, so the module
2411 * can provide parameter accessor functions of its own.
2412 */
2413 if (mod->module_init)
2414 flush_icache_range((unsigned long)mod->module_init,
2415 (unsigned long)mod->module_init
2416 + mod->init_size);
2417 flush_icache_range((unsigned long)mod->module_core,
2418 (unsigned long)mod->module_core + mod->core_size);
2419
2420 set_fs(old_fs);
2421
2422 mod->args = args;
2423 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2424 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2425 mod->name);
2426
2427 /* Now sew it into the lists so we can get lockdep and oops
2428 * info during argument parsing. Noone should access us, since
2429 * strong_try_module_get() will fail.
2430 * lockdep/oops can run asynchronous, so use the RCU list insertion
2431 * function to insert in a way safe to concurrent readers.
2432 * The mutex protects against concurrent writers.
2433 */
2434 list_add_rcu(&mod->list, &modules);
2435
2436 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2437 if (err < 0)
2438 goto unlink;
2439
2440 err = mod_sysfs_setup(mod, mod->kp, mod->num_kp);
2441 if (err < 0)
2442 goto unlink;
2443 add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2444 add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs);
2445
2446 /* Get rid of temporary copy */
2447 vfree(hdr);
2448
2449 trace_module_load(mod);
2450
2451 /* Done! */
2452 return mod;
2453
2454 unlink:
2455 /* Unlink carefully: kallsyms could be walking list. */
2456 list_del_rcu(&mod->list);
2457 synchronize_sched();
2458 module_arch_cleanup(mod);
2459 cleanup:
2460 free_modinfo(mod);
2461 kobject_del(&mod->mkobj.kobj);
2462 kobject_put(&mod->mkobj.kobj);
2463 free_unload:
2464 module_unload_free(mod);
2465#if defined(CONFIG_MODULE_UNLOAD)
2466 free_percpu(mod->refptr);
2467 free_init:
2468#endif
2469 module_free(mod, mod->module_init);
2470 free_core:
2471 module_free(mod, mod->module_core);
2472 /* mod will be freed with core. Don't access it beyond this line! */
2473 free_percpu:
2474 percpu_modfree(mod);
2475 free_mod:
2476 kfree(args);
2477 kfree(strmap);
2478 free_hdr:
2479 vfree(hdr);
2480 return ERR_PTR(err);
2481
2482 truncated:
2483 printk(KERN_ERR "Module len %lu truncated\n", len);
2484 err = -ENOEXEC;
2485 goto free_hdr;
2486}
2487
2488/* Call module constructors. */
2489static void do_mod_ctors(struct module *mod)
2490{
2491#ifdef CONFIG_CONSTRUCTORS
2492 unsigned long i;
2493
2494 for (i = 0; i < mod->num_ctors; i++)
2495 mod->ctors[i]();
2496#endif
2497}
2498
2499/* This is where the real work happens */
2500SYSCALL_DEFINE3(init_module, void __user *, umod,
2501 unsigned long, len, const char __user *, uargs)
2502{
2503 struct module *mod;
2504 int ret = 0;
2505
2506 /* Must have permission */
2507 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2508 return -EPERM;
2509
2510 /* Only one module load at a time, please */
2511 if (mutex_lock_interruptible(&module_mutex) != 0)
2512 return -EINTR;
2513
2514 /* Do all the hard work */
2515 mod = load_module(umod, len, uargs);
2516 if (IS_ERR(mod)) {
2517 mutex_unlock(&module_mutex);
2518 return PTR_ERR(mod);
2519 }
2520
2521 /* Drop lock so they can recurse */
2522 mutex_unlock(&module_mutex);
2523
2524 blocking_notifier_call_chain(&module_notify_list,
2525 MODULE_STATE_COMING, mod);
2526
2527 do_mod_ctors(mod);
2528 /* Start the module */
2529 if (mod->init != NULL)
2530 ret = do_one_initcall(mod->init);
2531 if (ret < 0) {
2532 /* Init routine failed: abort. Try to protect us from
2533 buggy refcounters. */
2534 mod->state = MODULE_STATE_GOING;
2535 synchronize_sched();
2536 module_put(mod);
2537 blocking_notifier_call_chain(&module_notify_list,
2538 MODULE_STATE_GOING, mod);
2539 mutex_lock(&module_mutex);
2540 free_module(mod);
2541 mutex_unlock(&module_mutex);
2542 wake_up(&module_wq);
2543 return ret;
2544 }
2545 if (ret > 0) {
2546 printk(KERN_WARNING
2547"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2548"%s: loading module anyway...\n",
2549 __func__, mod->name, ret,
2550 __func__);
2551 dump_stack();
2552 }
2553
2554 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2555 mod->state = MODULE_STATE_LIVE;
2556 wake_up(&module_wq);
2557 blocking_notifier_call_chain(&module_notify_list,
2558 MODULE_STATE_LIVE, mod);
2559
2560 /* We need to finish all async code before the module init sequence is done */
2561 async_synchronize_full();
2562
2563 mutex_lock(&module_mutex);
2564 /* Drop initial reference. */
2565 module_put(mod);
2566 trim_init_extable(mod);
2567#ifdef CONFIG_KALLSYMS
2568 mod->num_symtab = mod->core_num_syms;
2569 mod->symtab = mod->core_symtab;
2570 mod->strtab = mod->core_strtab;
2571#endif
2572 module_free(mod, mod->module_init);
2573 mod->module_init = NULL;
2574 mod->init_size = 0;
2575 mod->init_text_size = 0;
2576 mutex_unlock(&module_mutex);
2577
2578 return 0;
2579}
2580
2581static inline int within(unsigned long addr, void *start, unsigned long size)
2582{
2583 return ((void *)addr >= start && (void *)addr < start + size);
2584}
2585
2586#ifdef CONFIG_KALLSYMS
2587/*
2588 * This ignores the intensely annoying "mapping symbols" found
2589 * in ARM ELF files: $a, $t and $d.
2590 */
2591static inline int is_arm_mapping_symbol(const char *str)
2592{
2593 return str[0] == '$' && strchr("atd", str[1])
2594 && (str[2] == '\0' || str[2] == '.');
2595}
2596
2597static const char *get_ksymbol(struct module *mod,
2598 unsigned long addr,
2599 unsigned long *size,
2600 unsigned long *offset)
2601{
2602 unsigned int i, best = 0;
2603 unsigned long nextval;
2604
2605 /* At worse, next value is at end of module */
2606 if (within_module_init(addr, mod))
2607 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2608 else
2609 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2610
2611 /* Scan for closest preceeding symbol, and next symbol. (ELF
2612 starts real symbols at 1). */
2613 for (i = 1; i < mod->num_symtab; i++) {
2614 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2615 continue;
2616
2617 /* We ignore unnamed symbols: they're uninformative
2618 * and inserted at a whim. */
2619 if (mod->symtab[i].st_value <= addr
2620 && mod->symtab[i].st_value > mod->symtab[best].st_value
2621 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2622 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2623 best = i;
2624 if (mod->symtab[i].st_value > addr
2625 && mod->symtab[i].st_value < nextval
2626 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2627 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2628 nextval = mod->symtab[i].st_value;
2629 }
2630
2631 if (!best)
2632 return NULL;
2633
2634 if (size)
2635 *size = nextval - mod->symtab[best].st_value;
2636 if (offset)
2637 *offset = addr - mod->symtab[best].st_value;
2638 return mod->strtab + mod->symtab[best].st_name;
2639}
2640
2641/* For kallsyms to ask for address resolution. NULL means not found. Careful
2642 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2643const char *module_address_lookup(unsigned long addr,
2644 unsigned long *size,
2645 unsigned long *offset,
2646 char **modname,
2647 char *namebuf)
2648{
2649 struct module *mod;
2650 const char *ret = NULL;
2651
2652 preempt_disable();
2653 list_for_each_entry_rcu(mod, &modules, list) {
2654 if (within_module_init(addr, mod) ||
2655 within_module_core(addr, mod)) {
2656 if (modname)
2657 *modname = mod->name;
2658 ret = get_ksymbol(mod, addr, size, offset);
2659 break;
2660 }
2661 }
2662 /* Make a copy in here where it's safe */
2663 if (ret) {
2664 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2665 ret = namebuf;
2666 }
2667 preempt_enable();
2668 return ret;
2669}
2670
2671int lookup_module_symbol_name(unsigned long addr, char *symname)
2672{
2673 struct module *mod;
2674
2675 preempt_disable();
2676 list_for_each_entry_rcu(mod, &modules, list) {
2677 if (within_module_init(addr, mod) ||
2678 within_module_core(addr, mod)) {
2679 const char *sym;
2680
2681 sym = get_ksymbol(mod, addr, NULL, NULL);
2682 if (!sym)
2683 goto out;
2684 strlcpy(symname, sym, KSYM_NAME_LEN);
2685 preempt_enable();
2686 return 0;
2687 }
2688 }
2689out:
2690 preempt_enable();
2691 return -ERANGE;
2692}
2693
2694int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2695 unsigned long *offset, char *modname, char *name)
2696{
2697 struct module *mod;
2698
2699 preempt_disable();
2700 list_for_each_entry_rcu(mod, &modules, list) {
2701 if (within_module_init(addr, mod) ||
2702 within_module_core(addr, mod)) {
2703 const char *sym;
2704
2705 sym = get_ksymbol(mod, addr, size, offset);
2706 if (!sym)
2707 goto out;
2708 if (modname)
2709 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2710 if (name)
2711 strlcpy(name, sym, KSYM_NAME_LEN);
2712 preempt_enable();
2713 return 0;
2714 }
2715 }
2716out:
2717 preempt_enable();
2718 return -ERANGE;
2719}
2720
2721int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2722 char *name, char *module_name, int *exported)
2723{
2724 struct module *mod;
2725
2726 preempt_disable();
2727 list_for_each_entry_rcu(mod, &modules, list) {
2728 if (symnum < mod->num_symtab) {
2729 *value = mod->symtab[symnum].st_value;
2730 *type = mod->symtab[symnum].st_info;
2731 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2732 KSYM_NAME_LEN);
2733 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2734 *exported = is_exported(name, *value, mod);
2735 preempt_enable();
2736 return 0;
2737 }
2738 symnum -= mod->num_symtab;
2739 }
2740 preempt_enable();
2741 return -ERANGE;
2742}
2743
2744static unsigned long mod_find_symname(struct module *mod, const char *name)
2745{
2746 unsigned int i;
2747
2748 for (i = 0; i < mod->num_symtab; i++)
2749 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2750 mod->symtab[i].st_info != 'U')
2751 return mod->symtab[i].st_value;
2752 return 0;
2753}
2754
2755/* Look for this name: can be of form module:name. */
2756unsigned long module_kallsyms_lookup_name(const char *name)
2757{
2758 struct module *mod;
2759 char *colon;
2760 unsigned long ret = 0;
2761
2762 /* Don't lock: we're in enough trouble already. */
2763 preempt_disable();
2764 if ((colon = strchr(name, ':')) != NULL) {
2765 *colon = '\0';
2766 if ((mod = find_module(name)) != NULL)
2767 ret = mod_find_symname(mod, colon+1);
2768 *colon = ':';
2769 } else {
2770 list_for_each_entry_rcu(mod, &modules, list)
2771 if ((ret = mod_find_symname(mod, name)) != 0)
2772 break;
2773 }
2774 preempt_enable();
2775 return ret;
2776}
2777
2778int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
2779 struct module *, unsigned long),
2780 void *data)
2781{
2782 struct module *mod;
2783 unsigned int i;
2784 int ret;
2785
2786 list_for_each_entry(mod, &modules, list) {
2787 for (i = 0; i < mod->num_symtab; i++) {
2788 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
2789 mod, mod->symtab[i].st_value);
2790 if (ret != 0)
2791 return ret;
2792 }
2793 }
2794 return 0;
2795}
2796#endif /* CONFIG_KALLSYMS */
2797
2798static char *module_flags(struct module *mod, char *buf)
2799{
2800 int bx = 0;
2801
2802 if (mod->taints ||
2803 mod->state == MODULE_STATE_GOING ||
2804 mod->state == MODULE_STATE_COMING) {
2805 buf[bx++] = '(';
2806 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2807 buf[bx++] = 'P';
2808 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2809 buf[bx++] = 'F';
2810 if (mod->taints & (1 << TAINT_CRAP))
2811 buf[bx++] = 'C';
2812 /*
2813 * TAINT_FORCED_RMMOD: could be added.
2814 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2815 * apply to modules.
2816 */
2817
2818 /* Show a - for module-is-being-unloaded */
2819 if (mod->state == MODULE_STATE_GOING)
2820 buf[bx++] = '-';
2821 /* Show a + for module-is-being-loaded */
2822 if (mod->state == MODULE_STATE_COMING)
2823 buf[bx++] = '+';
2824 buf[bx++] = ')';
2825 }
2826 buf[bx] = '\0';
2827
2828 return buf;
2829}
2830
2831#ifdef CONFIG_PROC_FS
2832/* Called by the /proc file system to return a list of modules. */
2833static void *m_start(struct seq_file *m, loff_t *pos)
2834{
2835 mutex_lock(&module_mutex);
2836 return seq_list_start(&modules, *pos);
2837}
2838
2839static void *m_next(struct seq_file *m, void *p, loff_t *pos)
2840{
2841 return seq_list_next(p, &modules, pos);
2842}
2843
2844static void m_stop(struct seq_file *m, void *p)
2845{
2846 mutex_unlock(&module_mutex);
2847}
2848
2849static int m_show(struct seq_file *m, void *p)
2850{
2851 struct module *mod = list_entry(p, struct module, list);
2852 char buf[8];
2853
2854 seq_printf(m, "%s %u",
2855 mod->name, mod->init_size + mod->core_size);
2856 print_unload_info(m, mod);
2857
2858 /* Informative for users. */
2859 seq_printf(m, " %s",
2860 mod->state == MODULE_STATE_GOING ? "Unloading":
2861 mod->state == MODULE_STATE_COMING ? "Loading":
2862 "Live");
2863 /* Used by oprofile and other similar tools. */
2864 seq_printf(m, " 0x%p", mod->module_core);
2865
2866 /* Taints info */
2867 if (mod->taints)
2868 seq_printf(m, " %s", module_flags(mod, buf));
2869
2870 seq_printf(m, "\n");
2871 return 0;
2872}
2873
2874/* Format: modulename size refcount deps address
2875
2876 Where refcount is a number or -, and deps is a comma-separated list
2877 of depends or -.
2878*/
2879static const struct seq_operations modules_op = {
2880 .start = m_start,
2881 .next = m_next,
2882 .stop = m_stop,
2883 .show = m_show
2884};
2885
2886static int modules_open(struct inode *inode, struct file *file)
2887{
2888 return seq_open(file, &modules_op);
2889}
2890
2891static const struct file_operations proc_modules_operations = {
2892 .open = modules_open,
2893 .read = seq_read,
2894 .llseek = seq_lseek,
2895 .release = seq_release,
2896};
2897
2898static int __init proc_modules_init(void)
2899{
2900 proc_create("modules", 0, NULL, &proc_modules_operations);
2901 return 0;
2902}
2903module_init(proc_modules_init);
2904#endif
2905
2906/* Given an address, look for it in the module exception tables. */
2907const struct exception_table_entry *search_module_extables(unsigned long addr)
2908{
2909 const struct exception_table_entry *e = NULL;
2910 struct module *mod;
2911
2912 preempt_disable();
2913 list_for_each_entry_rcu(mod, &modules, list) {
2914 if (mod->num_exentries == 0)
2915 continue;
2916
2917 e = search_extable(mod->extable,
2918 mod->extable + mod->num_exentries - 1,
2919 addr);
2920 if (e)
2921 break;
2922 }
2923 preempt_enable();
2924
2925 /* Now, if we found one, we are running inside it now, hence
2926 we cannot unload the module, hence no refcnt needed. */
2927 return e;
2928}
2929
2930/*
2931 * is_module_address - is this address inside a module?
2932 * @addr: the address to check.
2933 *
2934 * See is_module_text_address() if you simply want to see if the address
2935 * is code (not data).
2936 */
2937bool is_module_address(unsigned long addr)
2938{
2939 bool ret;
2940
2941 preempt_disable();
2942 ret = __module_address(addr) != NULL;
2943 preempt_enable();
2944
2945 return ret;
2946}
2947
2948/*
2949 * __module_address - get the module which contains an address.
2950 * @addr: the address.
2951 *
2952 * Must be called with preempt disabled or module mutex held so that
2953 * module doesn't get freed during this.
2954 */
2955struct module *__module_address(unsigned long addr)
2956{
2957 struct module *mod;
2958
2959 if (addr < module_addr_min || addr > module_addr_max)
2960 return NULL;
2961
2962 list_for_each_entry_rcu(mod, &modules, list)
2963 if (within_module_core(addr, mod)
2964 || within_module_init(addr, mod))
2965 return mod;
2966 return NULL;
2967}
2968EXPORT_SYMBOL_GPL(__module_address);
2969
2970/*
2971 * is_module_text_address - is this address inside module code?
2972 * @addr: the address to check.
2973 *
2974 * See is_module_address() if you simply want to see if the address is
2975 * anywhere in a module. See kernel_text_address() for testing if an
2976 * address corresponds to kernel or module code.
2977 */
2978bool is_module_text_address(unsigned long addr)
2979{
2980 bool ret;
2981
2982 preempt_disable();
2983 ret = __module_text_address(addr) != NULL;
2984 preempt_enable();
2985
2986 return ret;
2987}
2988
2989/*
2990 * __module_text_address - get the module whose code contains an address.
2991 * @addr: the address.
2992 *
2993 * Must be called with preempt disabled or module mutex held so that
2994 * module doesn't get freed during this.
2995 */
2996struct module *__module_text_address(unsigned long addr)
2997{
2998 struct module *mod = __module_address(addr);
2999 if (mod) {
3000 /* Make sure it's within the text section. */
3001 if (!within(addr, mod->module_init, mod->init_text_size)
3002 && !within(addr, mod->module_core, mod->core_text_size))
3003 mod = NULL;
3004 }
3005 return mod;
3006}
3007EXPORT_SYMBOL_GPL(__module_text_address);
3008
3009/* Don't grab lock, we're oopsing. */
3010void print_modules(void)
3011{
3012 struct module *mod;
3013 char buf[8];
3014
3015 printk(KERN_DEFAULT "Modules linked in:");
3016 /* Most callers should already have preempt disabled, but make sure */
3017 preempt_disable();
3018 list_for_each_entry_rcu(mod, &modules, list)
3019 printk(" %s%s", mod->name, module_flags(mod, buf));
3020 preempt_enable();
3021 if (last_unloaded_module[0])
3022 printk(" [last unloaded: %s]", last_unloaded_module);
3023 printk("\n");
3024}
3025
3026#ifdef CONFIG_MODVERSIONS
3027/* Generate the signature for all relevant module structures here.
3028 * If these change, we don't want to try to parse the module. */
3029void module_layout(struct module *mod,
3030 struct modversion_info *ver,
3031 struct kernel_param *kp,
3032 struct kernel_symbol *ks,
3033 struct tracepoint *tp)
3034{
3035}
3036EXPORT_SYMBOL(module_layout);
3037#endif
3038
3039#ifdef CONFIG_TRACEPOINTS
3040void module_update_tracepoints(void)
3041{
3042 struct module *mod;
3043
3044 mutex_lock(&module_mutex);
3045 list_for_each_entry(mod, &modules, list)
3046 if (!mod->taints)
3047 tracepoint_update_probe_range(mod->tracepoints,
3048 mod->tracepoints + mod->num_tracepoints);
3049 mutex_unlock(&module_mutex);
3050}
3051
3052/*
3053 * Returns 0 if current not found.
3054 * Returns 1 if current found.
3055 */
3056int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3057{
3058 struct module *iter_mod;
3059 int found = 0;
3060
3061 mutex_lock(&module_mutex);
3062 list_for_each_entry(iter_mod, &modules, list) {
3063 if (!iter_mod->taints) {
3064 /*
3065 * Sorted module list
3066 */
3067 if (iter_mod < iter->module)
3068 continue;
3069 else if (iter_mod > iter->module)
3070 iter->tracepoint = NULL;
3071 found = tracepoint_get_iter_range(&iter->tracepoint,
3072 iter_mod->tracepoints,
3073 iter_mod->tracepoints
3074 + iter_mod->num_tracepoints);
3075 if (found) {
3076 iter->module = iter_mod;
3077 break;
3078 }
3079 }
3080 }
3081 mutex_unlock(&module_mutex);
3082 return found;
3083}
3084#endif