PM / Runtime: Add no_callbacks flag
[linux/fpc-iii.git] / kernel / module.c
blobccd641991842f4990906946f895fd5062a0389c3
1 /*
2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
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.
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.
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
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>
59 #define CREATE_TRACE_POINTS
60 #include <trace/events/module.h>
62 #if 0
63 #define DEBUGP printk
64 #else
65 #define DEBUGP(fmt , a...)
66 #endif
68 #ifndef ARCH_SHF_SMALL
69 #define ARCH_SHF_SMALL 0
70 #endif
72 /* If this is set, the section belongs in the init part of the module */
73 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
76 * Mutex protects:
77 * 1) List of modules (also safely readable with preempt_disable),
78 * 2) module_use links,
79 * 3) module_addr_min/module_addr_max.
80 * (delete uses stop_machine/add uses RCU list operations). */
81 DEFINE_MUTEX(module_mutex);
82 EXPORT_SYMBOL_GPL(module_mutex);
83 static LIST_HEAD(modules);
84 #ifdef CONFIG_KGDB_KDB
85 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
86 #endif /* CONFIG_KGDB_KDB */
89 /* Block module loading/unloading? */
90 int modules_disabled = 0;
92 /* Waiting for a module to finish initializing? */
93 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
95 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
97 /* Bounds of module allocation, for speeding __module_address.
98 * Protected by module_mutex. */
99 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
101 int register_module_notifier(struct notifier_block * nb)
103 return blocking_notifier_chain_register(&module_notify_list, nb);
105 EXPORT_SYMBOL(register_module_notifier);
107 int unregister_module_notifier(struct notifier_block * nb)
109 return blocking_notifier_chain_unregister(&module_notify_list, nb);
111 EXPORT_SYMBOL(unregister_module_notifier);
113 struct load_info {
114 Elf_Ehdr *hdr;
115 unsigned long len;
116 Elf_Shdr *sechdrs;
117 char *secstrings, *strtab;
118 unsigned long *strmap;
119 unsigned long symoffs, stroffs;
120 struct _ddebug *debug;
121 unsigned int num_debug;
122 struct {
123 unsigned int sym, str, mod, vers, info, pcpu;
124 } index;
127 /* We require a truly strong try_module_get(): 0 means failure due to
128 ongoing or failed initialization etc. */
129 static inline int strong_try_module_get(struct module *mod)
131 if (mod && mod->state == MODULE_STATE_COMING)
132 return -EBUSY;
133 if (try_module_get(mod))
134 return 0;
135 else
136 return -ENOENT;
139 static inline void add_taint_module(struct module *mod, unsigned flag)
141 add_taint(flag);
142 mod->taints |= (1U << flag);
146 * A thread that wants to hold a reference to a module only while it
147 * is running can call this to safely exit. nfsd and lockd use this.
149 void __module_put_and_exit(struct module *mod, long code)
151 module_put(mod);
152 do_exit(code);
154 EXPORT_SYMBOL(__module_put_and_exit);
156 /* Find a module section: 0 means not found. */
157 static unsigned int find_sec(const struct load_info *info, const char *name)
159 unsigned int i;
161 for (i = 1; i < info->hdr->e_shnum; i++) {
162 Elf_Shdr *shdr = &info->sechdrs[i];
163 /* Alloc bit cleared means "ignore it." */
164 if ((shdr->sh_flags & SHF_ALLOC)
165 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
166 return i;
168 return 0;
171 /* Find a module section, or NULL. */
172 static void *section_addr(const struct load_info *info, const char *name)
174 /* Section 0 has sh_addr 0. */
175 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
178 /* Find a module section, or NULL. Fill in number of "objects" in section. */
179 static void *section_objs(const struct load_info *info,
180 const char *name,
181 size_t object_size,
182 unsigned int *num)
184 unsigned int sec = find_sec(info, name);
186 /* Section 0 has sh_addr 0 and sh_size 0. */
187 *num = info->sechdrs[sec].sh_size / object_size;
188 return (void *)info->sechdrs[sec].sh_addr;
191 /* Provided by the linker */
192 extern const struct kernel_symbol __start___ksymtab[];
193 extern const struct kernel_symbol __stop___ksymtab[];
194 extern const struct kernel_symbol __start___ksymtab_gpl[];
195 extern const struct kernel_symbol __stop___ksymtab_gpl[];
196 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
197 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
198 extern const unsigned long __start___kcrctab[];
199 extern const unsigned long __start___kcrctab_gpl[];
200 extern const unsigned long __start___kcrctab_gpl_future[];
201 #ifdef CONFIG_UNUSED_SYMBOLS
202 extern const struct kernel_symbol __start___ksymtab_unused[];
203 extern const struct kernel_symbol __stop___ksymtab_unused[];
204 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
205 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
206 extern const unsigned long __start___kcrctab_unused[];
207 extern const unsigned long __start___kcrctab_unused_gpl[];
208 #endif
210 #ifndef CONFIG_MODVERSIONS
211 #define symversion(base, idx) NULL
212 #else
213 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
214 #endif
216 static bool each_symbol_in_section(const struct symsearch *arr,
217 unsigned int arrsize,
218 struct module *owner,
219 bool (*fn)(const struct symsearch *syms,
220 struct module *owner,
221 unsigned int symnum, void *data),
222 void *data)
224 unsigned int i, j;
226 for (j = 0; j < arrsize; j++) {
227 for (i = 0; i < arr[j].stop - arr[j].start; i++)
228 if (fn(&arr[j], owner, i, data))
229 return true;
232 return false;
235 /* Returns true as soon as fn returns true, otherwise false. */
236 bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
237 unsigned int symnum, void *data), void *data)
239 struct module *mod;
240 static const struct symsearch arr[] = {
241 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
242 NOT_GPL_ONLY, false },
243 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
244 __start___kcrctab_gpl,
245 GPL_ONLY, false },
246 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
247 __start___kcrctab_gpl_future,
248 WILL_BE_GPL_ONLY, false },
249 #ifdef CONFIG_UNUSED_SYMBOLS
250 { __start___ksymtab_unused, __stop___ksymtab_unused,
251 __start___kcrctab_unused,
252 NOT_GPL_ONLY, true },
253 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
254 __start___kcrctab_unused_gpl,
255 GPL_ONLY, true },
256 #endif
259 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
260 return true;
262 list_for_each_entry_rcu(mod, &modules, list) {
263 struct symsearch arr[] = {
264 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
265 NOT_GPL_ONLY, false },
266 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
267 mod->gpl_crcs,
268 GPL_ONLY, false },
269 { mod->gpl_future_syms,
270 mod->gpl_future_syms + mod->num_gpl_future_syms,
271 mod->gpl_future_crcs,
272 WILL_BE_GPL_ONLY, false },
273 #ifdef CONFIG_UNUSED_SYMBOLS
274 { mod->unused_syms,
275 mod->unused_syms + mod->num_unused_syms,
276 mod->unused_crcs,
277 NOT_GPL_ONLY, true },
278 { mod->unused_gpl_syms,
279 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
280 mod->unused_gpl_crcs,
281 GPL_ONLY, true },
282 #endif
285 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
286 return true;
288 return false;
290 EXPORT_SYMBOL_GPL(each_symbol);
292 struct find_symbol_arg {
293 /* Input */
294 const char *name;
295 bool gplok;
296 bool warn;
298 /* Output */
299 struct module *owner;
300 const unsigned long *crc;
301 const struct kernel_symbol *sym;
304 static bool find_symbol_in_section(const struct symsearch *syms,
305 struct module *owner,
306 unsigned int symnum, void *data)
308 struct find_symbol_arg *fsa = data;
310 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
311 return false;
313 if (!fsa->gplok) {
314 if (syms->licence == GPL_ONLY)
315 return false;
316 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
317 printk(KERN_WARNING "Symbol %s is being used "
318 "by a non-GPL module, which will not "
319 "be allowed in the future\n", fsa->name);
320 printk(KERN_WARNING "Please see the file "
321 "Documentation/feature-removal-schedule.txt "
322 "in the kernel source tree for more details.\n");
326 #ifdef CONFIG_UNUSED_SYMBOLS
327 if (syms->unused && fsa->warn) {
328 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
329 "however this module is using it.\n", fsa->name);
330 printk(KERN_WARNING
331 "This symbol will go away in the future.\n");
332 printk(KERN_WARNING
333 "Please evalute if this is the right api to use and if "
334 "it really is, submit a report the linux kernel "
335 "mailinglist together with submitting your code for "
336 "inclusion.\n");
338 #endif
340 fsa->owner = owner;
341 fsa->crc = symversion(syms->crcs, symnum);
342 fsa->sym = &syms->start[symnum];
343 return true;
346 /* Find a symbol and return it, along with, (optional) crc and
347 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
348 const struct kernel_symbol *find_symbol(const char *name,
349 struct module **owner,
350 const unsigned long **crc,
351 bool gplok,
352 bool warn)
354 struct find_symbol_arg fsa;
356 fsa.name = name;
357 fsa.gplok = gplok;
358 fsa.warn = warn;
360 if (each_symbol(find_symbol_in_section, &fsa)) {
361 if (owner)
362 *owner = fsa.owner;
363 if (crc)
364 *crc = fsa.crc;
365 return fsa.sym;
368 DEBUGP("Failed to find symbol %s\n", name);
369 return NULL;
371 EXPORT_SYMBOL_GPL(find_symbol);
373 /* Search for module by name: must hold module_mutex. */
374 struct module *find_module(const char *name)
376 struct module *mod;
378 list_for_each_entry(mod, &modules, list) {
379 if (strcmp(mod->name, name) == 0)
380 return mod;
382 return NULL;
384 EXPORT_SYMBOL_GPL(find_module);
386 #ifdef CONFIG_SMP
388 static inline void __percpu *mod_percpu(struct module *mod)
390 return mod->percpu;
393 static int percpu_modalloc(struct module *mod,
394 unsigned long size, unsigned long align)
396 if (align > PAGE_SIZE) {
397 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
398 mod->name, align, PAGE_SIZE);
399 align = PAGE_SIZE;
402 mod->percpu = __alloc_reserved_percpu(size, align);
403 if (!mod->percpu) {
404 printk(KERN_WARNING
405 "%s: Could not allocate %lu bytes percpu data\n",
406 mod->name, size);
407 return -ENOMEM;
409 mod->percpu_size = size;
410 return 0;
413 static void percpu_modfree(struct module *mod)
415 free_percpu(mod->percpu);
418 static unsigned int find_pcpusec(struct load_info *info)
420 return find_sec(info, ".data..percpu");
423 static void percpu_modcopy(struct module *mod,
424 const void *from, unsigned long size)
426 int cpu;
428 for_each_possible_cpu(cpu)
429 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
433 * is_module_percpu_address - test whether address is from module static percpu
434 * @addr: address to test
436 * Test whether @addr belongs to module static percpu area.
438 * RETURNS:
439 * %true if @addr is from module static percpu area
441 bool is_module_percpu_address(unsigned long addr)
443 struct module *mod;
444 unsigned int cpu;
446 preempt_disable();
448 list_for_each_entry_rcu(mod, &modules, list) {
449 if (!mod->percpu_size)
450 continue;
451 for_each_possible_cpu(cpu) {
452 void *start = per_cpu_ptr(mod->percpu, cpu);
454 if ((void *)addr >= start &&
455 (void *)addr < start + mod->percpu_size) {
456 preempt_enable();
457 return true;
462 preempt_enable();
463 return false;
466 #else /* ... !CONFIG_SMP */
468 static inline void __percpu *mod_percpu(struct module *mod)
470 return NULL;
472 static inline int percpu_modalloc(struct module *mod,
473 unsigned long size, unsigned long align)
475 return -ENOMEM;
477 static inline void percpu_modfree(struct module *mod)
480 static unsigned int find_pcpusec(struct load_info *info)
482 return 0;
484 static inline void percpu_modcopy(struct module *mod,
485 const void *from, unsigned long size)
487 /* pcpusec should be 0, and size of that section should be 0. */
488 BUG_ON(size != 0);
490 bool is_module_percpu_address(unsigned long addr)
492 return false;
495 #endif /* CONFIG_SMP */
497 #define MODINFO_ATTR(field) \
498 static void setup_modinfo_##field(struct module *mod, const char *s) \
500 mod->field = kstrdup(s, GFP_KERNEL); \
502 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
503 struct module *mod, char *buffer) \
505 return sprintf(buffer, "%s\n", mod->field); \
507 static int modinfo_##field##_exists(struct module *mod) \
509 return mod->field != NULL; \
511 static void free_modinfo_##field(struct module *mod) \
513 kfree(mod->field); \
514 mod->field = NULL; \
516 static struct module_attribute modinfo_##field = { \
517 .attr = { .name = __stringify(field), .mode = 0444 }, \
518 .show = show_modinfo_##field, \
519 .setup = setup_modinfo_##field, \
520 .test = modinfo_##field##_exists, \
521 .free = free_modinfo_##field, \
524 MODINFO_ATTR(version);
525 MODINFO_ATTR(srcversion);
527 static char last_unloaded_module[MODULE_NAME_LEN+1];
529 #ifdef CONFIG_MODULE_UNLOAD
531 EXPORT_TRACEPOINT_SYMBOL(module_get);
533 /* Init the unload section of the module. */
534 static int module_unload_init(struct module *mod)
536 mod->refptr = alloc_percpu(struct module_ref);
537 if (!mod->refptr)
538 return -ENOMEM;
540 INIT_LIST_HEAD(&mod->source_list);
541 INIT_LIST_HEAD(&mod->target_list);
543 /* Hold reference count during initialization. */
544 __this_cpu_write(mod->refptr->incs, 1);
545 /* Backwards compatibility macros put refcount during init. */
546 mod->waiter = current;
548 return 0;
551 /* Does a already use b? */
552 static int already_uses(struct module *a, struct module *b)
554 struct module_use *use;
556 list_for_each_entry(use, &b->source_list, source_list) {
557 if (use->source == a) {
558 DEBUGP("%s uses %s!\n", a->name, b->name);
559 return 1;
562 DEBUGP("%s does not use %s!\n", a->name, b->name);
563 return 0;
567 * Module a uses b
568 * - we add 'a' as a "source", 'b' as a "target" of module use
569 * - the module_use is added to the list of 'b' sources (so
570 * 'b' can walk the list to see who sourced them), and of 'a'
571 * targets (so 'a' can see what modules it targets).
573 static int add_module_usage(struct module *a, struct module *b)
575 struct module_use *use;
577 DEBUGP("Allocating new usage for %s.\n", a->name);
578 use = kmalloc(sizeof(*use), GFP_ATOMIC);
579 if (!use) {
580 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
581 return -ENOMEM;
584 use->source = a;
585 use->target = b;
586 list_add(&use->source_list, &b->source_list);
587 list_add(&use->target_list, &a->target_list);
588 return 0;
591 /* Module a uses b: caller needs module_mutex() */
592 int ref_module(struct module *a, struct module *b)
594 int err;
596 if (b == NULL || already_uses(a, b))
597 return 0;
599 /* If module isn't available, we fail. */
600 err = strong_try_module_get(b);
601 if (err)
602 return err;
604 err = add_module_usage(a, b);
605 if (err) {
606 module_put(b);
607 return err;
609 return 0;
611 EXPORT_SYMBOL_GPL(ref_module);
613 /* Clear the unload stuff of the module. */
614 static void module_unload_free(struct module *mod)
616 struct module_use *use, *tmp;
618 mutex_lock(&module_mutex);
619 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
620 struct module *i = use->target;
621 DEBUGP("%s unusing %s\n", mod->name, i->name);
622 module_put(i);
623 list_del(&use->source_list);
624 list_del(&use->target_list);
625 kfree(use);
627 mutex_unlock(&module_mutex);
629 free_percpu(mod->refptr);
632 #ifdef CONFIG_MODULE_FORCE_UNLOAD
633 static inline int try_force_unload(unsigned int flags)
635 int ret = (flags & O_TRUNC);
636 if (ret)
637 add_taint(TAINT_FORCED_RMMOD);
638 return ret;
640 #else
641 static inline int try_force_unload(unsigned int flags)
643 return 0;
645 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
647 struct stopref
649 struct module *mod;
650 int flags;
651 int *forced;
654 /* Whole machine is stopped with interrupts off when this runs. */
655 static int __try_stop_module(void *_sref)
657 struct stopref *sref = _sref;
659 /* If it's not unused, quit unless we're forcing. */
660 if (module_refcount(sref->mod) != 0) {
661 if (!(*sref->forced = try_force_unload(sref->flags)))
662 return -EWOULDBLOCK;
665 /* Mark it as dying. */
666 sref->mod->state = MODULE_STATE_GOING;
667 return 0;
670 static int try_stop_module(struct module *mod, int flags, int *forced)
672 if (flags & O_NONBLOCK) {
673 struct stopref sref = { mod, flags, forced };
675 return stop_machine(__try_stop_module, &sref, NULL);
676 } else {
677 /* We don't need to stop the machine for this. */
678 mod->state = MODULE_STATE_GOING;
679 synchronize_sched();
680 return 0;
684 unsigned int module_refcount(struct module *mod)
686 unsigned int incs = 0, decs = 0;
687 int cpu;
689 for_each_possible_cpu(cpu)
690 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
692 * ensure the incs are added up after the decs.
693 * module_put ensures incs are visible before decs with smp_wmb.
695 * This 2-count scheme avoids the situation where the refcount
696 * for CPU0 is read, then CPU0 increments the module refcount,
697 * then CPU1 drops that refcount, then the refcount for CPU1 is
698 * read. We would record a decrement but not its corresponding
699 * increment so we would see a low count (disaster).
701 * Rare situation? But module_refcount can be preempted, and we
702 * might be tallying up 4096+ CPUs. So it is not impossible.
704 smp_rmb();
705 for_each_possible_cpu(cpu)
706 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
707 return incs - decs;
709 EXPORT_SYMBOL(module_refcount);
711 /* This exists whether we can unload or not */
712 static void free_module(struct module *mod);
714 static void wait_for_zero_refcount(struct module *mod)
716 /* Since we might sleep for some time, release the mutex first */
717 mutex_unlock(&module_mutex);
718 for (;;) {
719 DEBUGP("Looking at refcount...\n");
720 set_current_state(TASK_UNINTERRUPTIBLE);
721 if (module_refcount(mod) == 0)
722 break;
723 schedule();
725 current->state = TASK_RUNNING;
726 mutex_lock(&module_mutex);
729 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
730 unsigned int, flags)
732 struct module *mod;
733 char name[MODULE_NAME_LEN];
734 int ret, forced = 0;
736 if (!capable(CAP_SYS_MODULE) || modules_disabled)
737 return -EPERM;
739 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
740 return -EFAULT;
741 name[MODULE_NAME_LEN-1] = '\0';
743 if (mutex_lock_interruptible(&module_mutex) != 0)
744 return -EINTR;
746 mod = find_module(name);
747 if (!mod) {
748 ret = -ENOENT;
749 goto out;
752 if (!list_empty(&mod->source_list)) {
753 /* Other modules depend on us: get rid of them first. */
754 ret = -EWOULDBLOCK;
755 goto out;
758 /* Doing init or already dying? */
759 if (mod->state != MODULE_STATE_LIVE) {
760 /* FIXME: if (force), slam module count and wake up
761 waiter --RR */
762 DEBUGP("%s already dying\n", mod->name);
763 ret = -EBUSY;
764 goto out;
767 /* If it has an init func, it must have an exit func to unload */
768 if (mod->init && !mod->exit) {
769 forced = try_force_unload(flags);
770 if (!forced) {
771 /* This module can't be removed */
772 ret = -EBUSY;
773 goto out;
777 /* Set this up before setting mod->state */
778 mod->waiter = current;
780 /* Stop the machine so refcounts can't move and disable module. */
781 ret = try_stop_module(mod, flags, &forced);
782 if (ret != 0)
783 goto out;
785 /* Never wait if forced. */
786 if (!forced && module_refcount(mod) != 0)
787 wait_for_zero_refcount(mod);
789 mutex_unlock(&module_mutex);
790 /* Final destruction now noone is using it. */
791 if (mod->exit != NULL)
792 mod->exit();
793 blocking_notifier_call_chain(&module_notify_list,
794 MODULE_STATE_GOING, mod);
795 async_synchronize_full();
797 /* Store the name of the last unloaded module for diagnostic purposes */
798 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
800 free_module(mod);
801 return 0;
802 out:
803 mutex_unlock(&module_mutex);
804 return ret;
807 static inline void print_unload_info(struct seq_file *m, struct module *mod)
809 struct module_use *use;
810 int printed_something = 0;
812 seq_printf(m, " %u ", module_refcount(mod));
814 /* Always include a trailing , so userspace can differentiate
815 between this and the old multi-field proc format. */
816 list_for_each_entry(use, &mod->source_list, source_list) {
817 printed_something = 1;
818 seq_printf(m, "%s,", use->source->name);
821 if (mod->init != NULL && mod->exit == NULL) {
822 printed_something = 1;
823 seq_printf(m, "[permanent],");
826 if (!printed_something)
827 seq_printf(m, "-");
830 void __symbol_put(const char *symbol)
832 struct module *owner;
834 preempt_disable();
835 if (!find_symbol(symbol, &owner, NULL, true, false))
836 BUG();
837 module_put(owner);
838 preempt_enable();
840 EXPORT_SYMBOL(__symbol_put);
842 /* Note this assumes addr is a function, which it currently always is. */
843 void symbol_put_addr(void *addr)
845 struct module *modaddr;
846 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
848 if (core_kernel_text(a))
849 return;
851 /* module_text_address is safe here: we're supposed to have reference
852 * to module from symbol_get, so it can't go away. */
853 modaddr = __module_text_address(a);
854 BUG_ON(!modaddr);
855 module_put(modaddr);
857 EXPORT_SYMBOL_GPL(symbol_put_addr);
859 static ssize_t show_refcnt(struct module_attribute *mattr,
860 struct module *mod, char *buffer)
862 return sprintf(buffer, "%u\n", module_refcount(mod));
865 static struct module_attribute refcnt = {
866 .attr = { .name = "refcnt", .mode = 0444 },
867 .show = show_refcnt,
870 void module_put(struct module *module)
872 if (module) {
873 preempt_disable();
874 smp_wmb(); /* see comment in module_refcount */
875 __this_cpu_inc(module->refptr->decs);
877 trace_module_put(module, _RET_IP_);
878 /* Maybe they're waiting for us to drop reference? */
879 if (unlikely(!module_is_live(module)))
880 wake_up_process(module->waiter);
881 preempt_enable();
884 EXPORT_SYMBOL(module_put);
886 #else /* !CONFIG_MODULE_UNLOAD */
887 static inline void print_unload_info(struct seq_file *m, struct module *mod)
889 /* We don't know the usage count, or what modules are using. */
890 seq_printf(m, " - -");
893 static inline void module_unload_free(struct module *mod)
897 int ref_module(struct module *a, struct module *b)
899 return strong_try_module_get(b);
901 EXPORT_SYMBOL_GPL(ref_module);
903 static inline int module_unload_init(struct module *mod)
905 return 0;
907 #endif /* CONFIG_MODULE_UNLOAD */
909 static ssize_t show_initstate(struct module_attribute *mattr,
910 struct module *mod, char *buffer)
912 const char *state = "unknown";
914 switch (mod->state) {
915 case MODULE_STATE_LIVE:
916 state = "live";
917 break;
918 case MODULE_STATE_COMING:
919 state = "coming";
920 break;
921 case MODULE_STATE_GOING:
922 state = "going";
923 break;
925 return sprintf(buffer, "%s\n", state);
928 static struct module_attribute initstate = {
929 .attr = { .name = "initstate", .mode = 0444 },
930 .show = show_initstate,
933 static struct module_attribute *modinfo_attrs[] = {
934 &modinfo_version,
935 &modinfo_srcversion,
936 &initstate,
937 #ifdef CONFIG_MODULE_UNLOAD
938 &refcnt,
939 #endif
940 NULL,
943 static const char vermagic[] = VERMAGIC_STRING;
945 static int try_to_force_load(struct module *mod, const char *reason)
947 #ifdef CONFIG_MODULE_FORCE_LOAD
948 if (!test_taint(TAINT_FORCED_MODULE))
949 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
950 mod->name, reason);
951 add_taint_module(mod, TAINT_FORCED_MODULE);
952 return 0;
953 #else
954 return -ENOEXEC;
955 #endif
958 #ifdef CONFIG_MODVERSIONS
959 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
960 static unsigned long maybe_relocated(unsigned long crc,
961 const struct module *crc_owner)
963 #ifdef ARCH_RELOCATES_KCRCTAB
964 if (crc_owner == NULL)
965 return crc - (unsigned long)reloc_start;
966 #endif
967 return crc;
970 static int check_version(Elf_Shdr *sechdrs,
971 unsigned int versindex,
972 const char *symname,
973 struct module *mod,
974 const unsigned long *crc,
975 const struct module *crc_owner)
977 unsigned int i, num_versions;
978 struct modversion_info *versions;
980 /* Exporting module didn't supply crcs? OK, we're already tainted. */
981 if (!crc)
982 return 1;
984 /* No versions at all? modprobe --force does this. */
985 if (versindex == 0)
986 return try_to_force_load(mod, symname) == 0;
988 versions = (void *) sechdrs[versindex].sh_addr;
989 num_versions = sechdrs[versindex].sh_size
990 / sizeof(struct modversion_info);
992 for (i = 0; i < num_versions; i++) {
993 if (strcmp(versions[i].name, symname) != 0)
994 continue;
996 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
997 return 1;
998 DEBUGP("Found checksum %lX vs module %lX\n",
999 maybe_relocated(*crc, crc_owner), versions[i].crc);
1000 goto bad_version;
1003 printk(KERN_WARNING "%s: no symbol version for %s\n",
1004 mod->name, symname);
1005 return 0;
1007 bad_version:
1008 printk("%s: disagrees about version of symbol %s\n",
1009 mod->name, symname);
1010 return 0;
1013 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1014 unsigned int versindex,
1015 struct module *mod)
1017 const unsigned long *crc;
1019 /* Since this should be found in kernel (which can't be removed),
1020 * no locking is necessary. */
1021 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1022 &crc, true, false))
1023 BUG();
1024 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1025 NULL);
1028 /* First part is kernel version, which we ignore if module has crcs. */
1029 static inline int same_magic(const char *amagic, const char *bmagic,
1030 bool has_crcs)
1032 if (has_crcs) {
1033 amagic += strcspn(amagic, " ");
1034 bmagic += strcspn(bmagic, " ");
1036 return strcmp(amagic, bmagic) == 0;
1038 #else
1039 static inline int check_version(Elf_Shdr *sechdrs,
1040 unsigned int versindex,
1041 const char *symname,
1042 struct module *mod,
1043 const unsigned long *crc,
1044 const struct module *crc_owner)
1046 return 1;
1049 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1050 unsigned int versindex,
1051 struct module *mod)
1053 return 1;
1056 static inline int same_magic(const char *amagic, const char *bmagic,
1057 bool has_crcs)
1059 return strcmp(amagic, bmagic) == 0;
1061 #endif /* CONFIG_MODVERSIONS */
1063 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1064 static const struct kernel_symbol *resolve_symbol(struct module *mod,
1065 const struct load_info *info,
1066 const char *name,
1067 char ownername[])
1069 struct module *owner;
1070 const struct kernel_symbol *sym;
1071 const unsigned long *crc;
1072 int err;
1074 mutex_lock(&module_mutex);
1075 sym = find_symbol(name, &owner, &crc,
1076 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1077 if (!sym)
1078 goto unlock;
1080 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1081 owner)) {
1082 sym = ERR_PTR(-EINVAL);
1083 goto getname;
1086 err = ref_module(mod, owner);
1087 if (err) {
1088 sym = ERR_PTR(err);
1089 goto getname;
1092 getname:
1093 /* We must make copy under the lock if we failed to get ref. */
1094 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1095 unlock:
1096 mutex_unlock(&module_mutex);
1097 return sym;
1100 static const struct kernel_symbol *
1101 resolve_symbol_wait(struct module *mod,
1102 const struct load_info *info,
1103 const char *name)
1105 const struct kernel_symbol *ksym;
1106 char owner[MODULE_NAME_LEN];
1108 if (wait_event_interruptible_timeout(module_wq,
1109 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1110 || PTR_ERR(ksym) != -EBUSY,
1111 30 * HZ) <= 0) {
1112 printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
1113 mod->name, owner);
1115 return ksym;
1119 * /sys/module/foo/sections stuff
1120 * J. Corbet <corbet@lwn.net>
1122 #ifdef CONFIG_SYSFS
1124 #ifdef CONFIG_KALLSYMS
1125 static inline bool sect_empty(const Elf_Shdr *sect)
1127 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1130 struct module_sect_attr
1132 struct module_attribute mattr;
1133 char *name;
1134 unsigned long address;
1137 struct module_sect_attrs
1139 struct attribute_group grp;
1140 unsigned int nsections;
1141 struct module_sect_attr attrs[0];
1144 static ssize_t module_sect_show(struct module_attribute *mattr,
1145 struct module *mod, char *buf)
1147 struct module_sect_attr *sattr =
1148 container_of(mattr, struct module_sect_attr, mattr);
1149 return sprintf(buf, "0x%lx\n", sattr->address);
1152 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1154 unsigned int section;
1156 for (section = 0; section < sect_attrs->nsections; section++)
1157 kfree(sect_attrs->attrs[section].name);
1158 kfree(sect_attrs);
1161 static void add_sect_attrs(struct module *mod, const struct load_info *info)
1163 unsigned int nloaded = 0, i, size[2];
1164 struct module_sect_attrs *sect_attrs;
1165 struct module_sect_attr *sattr;
1166 struct attribute **gattr;
1168 /* Count loaded sections and allocate structures */
1169 for (i = 0; i < info->hdr->e_shnum; i++)
1170 if (!sect_empty(&info->sechdrs[i]))
1171 nloaded++;
1172 size[0] = ALIGN(sizeof(*sect_attrs)
1173 + nloaded * sizeof(sect_attrs->attrs[0]),
1174 sizeof(sect_attrs->grp.attrs[0]));
1175 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1176 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1177 if (sect_attrs == NULL)
1178 return;
1180 /* Setup section attributes. */
1181 sect_attrs->grp.name = "sections";
1182 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1184 sect_attrs->nsections = 0;
1185 sattr = &sect_attrs->attrs[0];
1186 gattr = &sect_attrs->grp.attrs[0];
1187 for (i = 0; i < info->hdr->e_shnum; i++) {
1188 Elf_Shdr *sec = &info->sechdrs[i];
1189 if (sect_empty(sec))
1190 continue;
1191 sattr->address = sec->sh_addr;
1192 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1193 GFP_KERNEL);
1194 if (sattr->name == NULL)
1195 goto out;
1196 sect_attrs->nsections++;
1197 sysfs_attr_init(&sattr->mattr.attr);
1198 sattr->mattr.show = module_sect_show;
1199 sattr->mattr.store = NULL;
1200 sattr->mattr.attr.name = sattr->name;
1201 sattr->mattr.attr.mode = S_IRUGO;
1202 *(gattr++) = &(sattr++)->mattr.attr;
1204 *gattr = NULL;
1206 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1207 goto out;
1209 mod->sect_attrs = sect_attrs;
1210 return;
1211 out:
1212 free_sect_attrs(sect_attrs);
1215 static void remove_sect_attrs(struct module *mod)
1217 if (mod->sect_attrs) {
1218 sysfs_remove_group(&mod->mkobj.kobj,
1219 &mod->sect_attrs->grp);
1220 /* We are positive that no one is using any sect attrs
1221 * at this point. Deallocate immediately. */
1222 free_sect_attrs(mod->sect_attrs);
1223 mod->sect_attrs = NULL;
1228 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1231 struct module_notes_attrs {
1232 struct kobject *dir;
1233 unsigned int notes;
1234 struct bin_attribute attrs[0];
1237 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1238 struct bin_attribute *bin_attr,
1239 char *buf, loff_t pos, size_t count)
1242 * The caller checked the pos and count against our size.
1244 memcpy(buf, bin_attr->private + pos, count);
1245 return count;
1248 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1249 unsigned int i)
1251 if (notes_attrs->dir) {
1252 while (i-- > 0)
1253 sysfs_remove_bin_file(notes_attrs->dir,
1254 &notes_attrs->attrs[i]);
1255 kobject_put(notes_attrs->dir);
1257 kfree(notes_attrs);
1260 static void add_notes_attrs(struct module *mod, const struct load_info *info)
1262 unsigned int notes, loaded, i;
1263 struct module_notes_attrs *notes_attrs;
1264 struct bin_attribute *nattr;
1266 /* failed to create section attributes, so can't create notes */
1267 if (!mod->sect_attrs)
1268 return;
1270 /* Count notes sections and allocate structures. */
1271 notes = 0;
1272 for (i = 0; i < info->hdr->e_shnum; i++)
1273 if (!sect_empty(&info->sechdrs[i]) &&
1274 (info->sechdrs[i].sh_type == SHT_NOTE))
1275 ++notes;
1277 if (notes == 0)
1278 return;
1280 notes_attrs = kzalloc(sizeof(*notes_attrs)
1281 + notes * sizeof(notes_attrs->attrs[0]),
1282 GFP_KERNEL);
1283 if (notes_attrs == NULL)
1284 return;
1286 notes_attrs->notes = notes;
1287 nattr = &notes_attrs->attrs[0];
1288 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1289 if (sect_empty(&info->sechdrs[i]))
1290 continue;
1291 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1292 sysfs_bin_attr_init(nattr);
1293 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1294 nattr->attr.mode = S_IRUGO;
1295 nattr->size = info->sechdrs[i].sh_size;
1296 nattr->private = (void *) info->sechdrs[i].sh_addr;
1297 nattr->read = module_notes_read;
1298 ++nattr;
1300 ++loaded;
1303 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1304 if (!notes_attrs->dir)
1305 goto out;
1307 for (i = 0; i < notes; ++i)
1308 if (sysfs_create_bin_file(notes_attrs->dir,
1309 &notes_attrs->attrs[i]))
1310 goto out;
1312 mod->notes_attrs = notes_attrs;
1313 return;
1315 out:
1316 free_notes_attrs(notes_attrs, i);
1319 static void remove_notes_attrs(struct module *mod)
1321 if (mod->notes_attrs)
1322 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1325 #else
1327 static inline void add_sect_attrs(struct module *mod,
1328 const struct load_info *info)
1332 static inline void remove_sect_attrs(struct module *mod)
1336 static inline void add_notes_attrs(struct module *mod,
1337 const struct load_info *info)
1341 static inline void remove_notes_attrs(struct module *mod)
1344 #endif /* CONFIG_KALLSYMS */
1346 static void add_usage_links(struct module *mod)
1348 #ifdef CONFIG_MODULE_UNLOAD
1349 struct module_use *use;
1350 int nowarn;
1352 mutex_lock(&module_mutex);
1353 list_for_each_entry(use, &mod->target_list, target_list) {
1354 nowarn = sysfs_create_link(use->target->holders_dir,
1355 &mod->mkobj.kobj, mod->name);
1357 mutex_unlock(&module_mutex);
1358 #endif
1361 static void del_usage_links(struct module *mod)
1363 #ifdef CONFIG_MODULE_UNLOAD
1364 struct module_use *use;
1366 mutex_lock(&module_mutex);
1367 list_for_each_entry(use, &mod->target_list, target_list)
1368 sysfs_remove_link(use->target->holders_dir, mod->name);
1369 mutex_unlock(&module_mutex);
1370 #endif
1373 static int module_add_modinfo_attrs(struct module *mod)
1375 struct module_attribute *attr;
1376 struct module_attribute *temp_attr;
1377 int error = 0;
1378 int i;
1380 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1381 (ARRAY_SIZE(modinfo_attrs) + 1)),
1382 GFP_KERNEL);
1383 if (!mod->modinfo_attrs)
1384 return -ENOMEM;
1386 temp_attr = mod->modinfo_attrs;
1387 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1388 if (!attr->test ||
1389 (attr->test && attr->test(mod))) {
1390 memcpy(temp_attr, attr, sizeof(*temp_attr));
1391 sysfs_attr_init(&temp_attr->attr);
1392 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1393 ++temp_attr;
1396 return error;
1399 static void module_remove_modinfo_attrs(struct module *mod)
1401 struct module_attribute *attr;
1402 int i;
1404 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1405 /* pick a field to test for end of list */
1406 if (!attr->attr.name)
1407 break;
1408 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1409 if (attr->free)
1410 attr->free(mod);
1412 kfree(mod->modinfo_attrs);
1415 static int mod_sysfs_init(struct module *mod)
1417 int err;
1418 struct kobject *kobj;
1420 if (!module_sysfs_initialized) {
1421 printk(KERN_ERR "%s: module sysfs not initialized\n",
1422 mod->name);
1423 err = -EINVAL;
1424 goto out;
1427 kobj = kset_find_obj(module_kset, mod->name);
1428 if (kobj) {
1429 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1430 kobject_put(kobj);
1431 err = -EINVAL;
1432 goto out;
1435 mod->mkobj.mod = mod;
1437 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1438 mod->mkobj.kobj.kset = module_kset;
1439 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1440 "%s", mod->name);
1441 if (err)
1442 kobject_put(&mod->mkobj.kobj);
1444 /* delay uevent until full sysfs population */
1445 out:
1446 return err;
1449 static int mod_sysfs_setup(struct module *mod,
1450 const struct load_info *info,
1451 struct kernel_param *kparam,
1452 unsigned int num_params)
1454 int err;
1456 err = mod_sysfs_init(mod);
1457 if (err)
1458 goto out;
1460 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1461 if (!mod->holders_dir) {
1462 err = -ENOMEM;
1463 goto out_unreg;
1466 err = module_param_sysfs_setup(mod, kparam, num_params);
1467 if (err)
1468 goto out_unreg_holders;
1470 err = module_add_modinfo_attrs(mod);
1471 if (err)
1472 goto out_unreg_param;
1474 add_usage_links(mod);
1475 add_sect_attrs(mod, info);
1476 add_notes_attrs(mod, info);
1478 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1479 return 0;
1481 out_unreg_param:
1482 module_param_sysfs_remove(mod);
1483 out_unreg_holders:
1484 kobject_put(mod->holders_dir);
1485 out_unreg:
1486 kobject_put(&mod->mkobj.kobj);
1487 out:
1488 return err;
1491 static void mod_sysfs_fini(struct module *mod)
1493 remove_notes_attrs(mod);
1494 remove_sect_attrs(mod);
1495 kobject_put(&mod->mkobj.kobj);
1498 #else /* !CONFIG_SYSFS */
1500 static int mod_sysfs_setup(struct module *mod,
1501 const struct load_info *info,
1502 struct kernel_param *kparam,
1503 unsigned int num_params)
1505 return 0;
1508 static void mod_sysfs_fini(struct module *mod)
1512 static void module_remove_modinfo_attrs(struct module *mod)
1516 static void del_usage_links(struct module *mod)
1520 #endif /* CONFIG_SYSFS */
1522 static void mod_sysfs_teardown(struct module *mod)
1524 del_usage_links(mod);
1525 module_remove_modinfo_attrs(mod);
1526 module_param_sysfs_remove(mod);
1527 kobject_put(mod->mkobj.drivers_dir);
1528 kobject_put(mod->holders_dir);
1529 mod_sysfs_fini(mod);
1533 * unlink the module with the whole machine is stopped with interrupts off
1534 * - this defends against kallsyms not taking locks
1536 static int __unlink_module(void *_mod)
1538 struct module *mod = _mod;
1539 list_del(&mod->list);
1540 module_bug_cleanup(mod);
1541 return 0;
1544 /* Free a module, remove from lists, etc. */
1545 static void free_module(struct module *mod)
1547 trace_module_free(mod);
1549 /* Delete from various lists */
1550 mutex_lock(&module_mutex);
1551 stop_machine(__unlink_module, mod, NULL);
1552 mutex_unlock(&module_mutex);
1553 mod_sysfs_teardown(mod);
1555 /* Remove dynamic debug info */
1556 ddebug_remove_module(mod->name);
1558 /* Arch-specific cleanup. */
1559 module_arch_cleanup(mod);
1561 /* Module unload stuff */
1562 module_unload_free(mod);
1564 /* Free any allocated parameters. */
1565 destroy_params(mod->kp, mod->num_kp);
1567 /* This may be NULL, but that's OK */
1568 module_free(mod, mod->module_init);
1569 kfree(mod->args);
1570 percpu_modfree(mod);
1572 /* Free lock-classes: */
1573 lockdep_free_key_range(mod->module_core, mod->core_size);
1575 /* Finally, free the core (containing the module structure) */
1576 module_free(mod, mod->module_core);
1578 #ifdef CONFIG_MPU
1579 update_protections(current->mm);
1580 #endif
1583 void *__symbol_get(const char *symbol)
1585 struct module *owner;
1586 const struct kernel_symbol *sym;
1588 preempt_disable();
1589 sym = find_symbol(symbol, &owner, NULL, true, true);
1590 if (sym && strong_try_module_get(owner))
1591 sym = NULL;
1592 preempt_enable();
1594 return sym ? (void *)sym->value : NULL;
1596 EXPORT_SYMBOL_GPL(__symbol_get);
1599 * Ensure that an exported symbol [global namespace] does not already exist
1600 * in the kernel or in some other module's exported symbol table.
1602 * You must hold the module_mutex.
1604 static int verify_export_symbols(struct module *mod)
1606 unsigned int i;
1607 struct module *owner;
1608 const struct kernel_symbol *s;
1609 struct {
1610 const struct kernel_symbol *sym;
1611 unsigned int num;
1612 } arr[] = {
1613 { mod->syms, mod->num_syms },
1614 { mod->gpl_syms, mod->num_gpl_syms },
1615 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1616 #ifdef CONFIG_UNUSED_SYMBOLS
1617 { mod->unused_syms, mod->num_unused_syms },
1618 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1619 #endif
1622 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1623 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1624 if (find_symbol(s->name, &owner, NULL, true, false)) {
1625 printk(KERN_ERR
1626 "%s: exports duplicate symbol %s"
1627 " (owned by %s)\n",
1628 mod->name, s->name, module_name(owner));
1629 return -ENOEXEC;
1633 return 0;
1636 /* Change all symbols so that st_value encodes the pointer directly. */
1637 static int simplify_symbols(struct module *mod, const struct load_info *info)
1639 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
1640 Elf_Sym *sym = (void *)symsec->sh_addr;
1641 unsigned long secbase;
1642 unsigned int i;
1643 int ret = 0;
1644 const struct kernel_symbol *ksym;
1646 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
1647 const char *name = info->strtab + sym[i].st_name;
1649 switch (sym[i].st_shndx) {
1650 case SHN_COMMON:
1651 /* We compiled with -fno-common. These are not
1652 supposed to happen. */
1653 DEBUGP("Common symbol: %s\n", name);
1654 printk("%s: please compile with -fno-common\n",
1655 mod->name);
1656 ret = -ENOEXEC;
1657 break;
1659 case SHN_ABS:
1660 /* Don't need to do anything */
1661 DEBUGP("Absolute symbol: 0x%08lx\n",
1662 (long)sym[i].st_value);
1663 break;
1665 case SHN_UNDEF:
1666 ksym = resolve_symbol_wait(mod, info, name);
1667 /* Ok if resolved. */
1668 if (ksym && !IS_ERR(ksym)) {
1669 sym[i].st_value = ksym->value;
1670 break;
1673 /* Ok if weak. */
1674 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1675 break;
1677 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
1678 mod->name, name, PTR_ERR(ksym));
1679 ret = PTR_ERR(ksym) ?: -ENOENT;
1680 break;
1682 default:
1683 /* Divert to percpu allocation if a percpu var. */
1684 if (sym[i].st_shndx == info->index.pcpu)
1685 secbase = (unsigned long)mod_percpu(mod);
1686 else
1687 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
1688 sym[i].st_value += secbase;
1689 break;
1693 return ret;
1696 static int apply_relocations(struct module *mod, const struct load_info *info)
1698 unsigned int i;
1699 int err = 0;
1701 /* Now do relocations. */
1702 for (i = 1; i < info->hdr->e_shnum; i++) {
1703 unsigned int infosec = info->sechdrs[i].sh_info;
1705 /* Not a valid relocation section? */
1706 if (infosec >= info->hdr->e_shnum)
1707 continue;
1709 /* Don't bother with non-allocated sections */
1710 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
1711 continue;
1713 if (info->sechdrs[i].sh_type == SHT_REL)
1714 err = apply_relocate(info->sechdrs, info->strtab,
1715 info->index.sym, i, mod);
1716 else if (info->sechdrs[i].sh_type == SHT_RELA)
1717 err = apply_relocate_add(info->sechdrs, info->strtab,
1718 info->index.sym, i, mod);
1719 if (err < 0)
1720 break;
1722 return err;
1725 /* Additional bytes needed by arch in front of individual sections */
1726 unsigned int __weak arch_mod_section_prepend(struct module *mod,
1727 unsigned int section)
1729 /* default implementation just returns zero */
1730 return 0;
1733 /* Update size with this section: return offset. */
1734 static long get_offset(struct module *mod, unsigned int *size,
1735 Elf_Shdr *sechdr, unsigned int section)
1737 long ret;
1739 *size += arch_mod_section_prepend(mod, section);
1740 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1741 *size = ret + sechdr->sh_size;
1742 return ret;
1745 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1746 might -- code, read-only data, read-write data, small data. Tally
1747 sizes, and place the offsets into sh_entsize fields: high bit means it
1748 belongs in init. */
1749 static void layout_sections(struct module *mod, struct load_info *info)
1751 static unsigned long const masks[][2] = {
1752 /* NOTE: all executable code must be the first section
1753 * in this array; otherwise modify the text_size
1754 * finder in the two loops below */
1755 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1756 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1757 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1758 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1760 unsigned int m, i;
1762 for (i = 0; i < info->hdr->e_shnum; i++)
1763 info->sechdrs[i].sh_entsize = ~0UL;
1765 DEBUGP("Core section allocation order:\n");
1766 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1767 for (i = 0; i < info->hdr->e_shnum; ++i) {
1768 Elf_Shdr *s = &info->sechdrs[i];
1769 const char *sname = info->secstrings + s->sh_name;
1771 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1772 || (s->sh_flags & masks[m][1])
1773 || s->sh_entsize != ~0UL
1774 || strstarts(sname, ".init"))
1775 continue;
1776 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1777 DEBUGP("\t%s\n", name);
1779 if (m == 0)
1780 mod->core_text_size = mod->core_size;
1783 DEBUGP("Init section allocation order:\n");
1784 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1785 for (i = 0; i < info->hdr->e_shnum; ++i) {
1786 Elf_Shdr *s = &info->sechdrs[i];
1787 const char *sname = info->secstrings + s->sh_name;
1789 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1790 || (s->sh_flags & masks[m][1])
1791 || s->sh_entsize != ~0UL
1792 || !strstarts(sname, ".init"))
1793 continue;
1794 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1795 | INIT_OFFSET_MASK);
1796 DEBUGP("\t%s\n", sname);
1798 if (m == 0)
1799 mod->init_text_size = mod->init_size;
1803 static void set_license(struct module *mod, const char *license)
1805 if (!license)
1806 license = "unspecified";
1808 if (!license_is_gpl_compatible(license)) {
1809 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1810 printk(KERN_WARNING "%s: module license '%s' taints "
1811 "kernel.\n", mod->name, license);
1812 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1816 /* Parse tag=value strings from .modinfo section */
1817 static char *next_string(char *string, unsigned long *secsize)
1819 /* Skip non-zero chars */
1820 while (string[0]) {
1821 string++;
1822 if ((*secsize)-- <= 1)
1823 return NULL;
1826 /* Skip any zero padding. */
1827 while (!string[0]) {
1828 string++;
1829 if ((*secsize)-- <= 1)
1830 return NULL;
1832 return string;
1835 static char *get_modinfo(struct load_info *info, const char *tag)
1837 char *p;
1838 unsigned int taglen = strlen(tag);
1839 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
1840 unsigned long size = infosec->sh_size;
1842 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
1843 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1844 return p + taglen + 1;
1846 return NULL;
1849 static void setup_modinfo(struct module *mod, struct load_info *info)
1851 struct module_attribute *attr;
1852 int i;
1854 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1855 if (attr->setup)
1856 attr->setup(mod, get_modinfo(info, attr->attr.name));
1860 static void free_modinfo(struct module *mod)
1862 struct module_attribute *attr;
1863 int i;
1865 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1866 if (attr->free)
1867 attr->free(mod);
1871 #ifdef CONFIG_KALLSYMS
1873 /* lookup symbol in given range of kernel_symbols */
1874 static const struct kernel_symbol *lookup_symbol(const char *name,
1875 const struct kernel_symbol *start,
1876 const struct kernel_symbol *stop)
1878 const struct kernel_symbol *ks = start;
1879 for (; ks < stop; ks++)
1880 if (strcmp(ks->name, name) == 0)
1881 return ks;
1882 return NULL;
1885 static int is_exported(const char *name, unsigned long value,
1886 const struct module *mod)
1888 const struct kernel_symbol *ks;
1889 if (!mod)
1890 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1891 else
1892 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1893 return ks != NULL && ks->value == value;
1896 /* As per nm */
1897 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
1899 const Elf_Shdr *sechdrs = info->sechdrs;
1901 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1902 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1903 return 'v';
1904 else
1905 return 'w';
1907 if (sym->st_shndx == SHN_UNDEF)
1908 return 'U';
1909 if (sym->st_shndx == SHN_ABS)
1910 return 'a';
1911 if (sym->st_shndx >= SHN_LORESERVE)
1912 return '?';
1913 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1914 return 't';
1915 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1916 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1917 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1918 return 'r';
1919 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1920 return 'g';
1921 else
1922 return 'd';
1924 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1925 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1926 return 's';
1927 else
1928 return 'b';
1930 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
1931 ".debug")) {
1932 return 'n';
1934 return '?';
1937 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1938 unsigned int shnum)
1940 const Elf_Shdr *sec;
1942 if (src->st_shndx == SHN_UNDEF
1943 || src->st_shndx >= shnum
1944 || !src->st_name)
1945 return false;
1947 sec = sechdrs + src->st_shndx;
1948 if (!(sec->sh_flags & SHF_ALLOC)
1949 #ifndef CONFIG_KALLSYMS_ALL
1950 || !(sec->sh_flags & SHF_EXECINSTR)
1951 #endif
1952 || (sec->sh_entsize & INIT_OFFSET_MASK))
1953 return false;
1955 return true;
1958 static void layout_symtab(struct module *mod, struct load_info *info)
1960 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
1961 Elf_Shdr *strsect = info->sechdrs + info->index.str;
1962 const Elf_Sym *src;
1963 unsigned int i, nsrc, ndst;
1965 /* Put symbol section at end of init part of module. */
1966 symsect->sh_flags |= SHF_ALLOC;
1967 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1968 info->index.sym) | INIT_OFFSET_MASK;
1969 DEBUGP("\t%s\n", info->secstrings + symsect->sh_name);
1971 src = (void *)info->hdr + symsect->sh_offset;
1972 nsrc = symsect->sh_size / sizeof(*src);
1973 for (ndst = i = 1; i < nsrc; ++i, ++src)
1974 if (is_core_symbol(src, info->sechdrs, info->hdr->e_shnum)) {
1975 unsigned int j = src->st_name;
1977 while (!__test_and_set_bit(j, info->strmap)
1978 && info->strtab[j])
1979 ++j;
1980 ++ndst;
1983 /* Append room for core symbols at end of core part. */
1984 info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
1985 mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym);
1987 /* Put string table section at end of init part of module. */
1988 strsect->sh_flags |= SHF_ALLOC;
1989 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
1990 info->index.str) | INIT_OFFSET_MASK;
1991 DEBUGP("\t%s\n", info->secstrings + strsect->sh_name);
1993 /* Append room for core symbols' strings at end of core part. */
1994 info->stroffs = mod->core_size;
1995 __set_bit(0, info->strmap);
1996 mod->core_size += bitmap_weight(info->strmap, strsect->sh_size);
1999 static void add_kallsyms(struct module *mod, const struct load_info *info)
2001 unsigned int i, ndst;
2002 const Elf_Sym *src;
2003 Elf_Sym *dst;
2004 char *s;
2005 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2007 mod->symtab = (void *)symsec->sh_addr;
2008 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2009 /* Make sure we get permanent strtab: don't use info->strtab. */
2010 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2012 /* Set types up while we still have access to sections. */
2013 for (i = 0; i < mod->num_symtab; i++)
2014 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
2016 mod->core_symtab = dst = mod->module_core + info->symoffs;
2017 src = mod->symtab;
2018 *dst = *src;
2019 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
2020 if (!is_core_symbol(src, info->sechdrs, info->hdr->e_shnum))
2021 continue;
2022 dst[ndst] = *src;
2023 dst[ndst].st_name = bitmap_weight(info->strmap,
2024 dst[ndst].st_name);
2025 ++ndst;
2027 mod->core_num_syms = ndst;
2029 mod->core_strtab = s = mod->module_core + info->stroffs;
2030 for (*s = 0, i = 1; i < info->sechdrs[info->index.str].sh_size; ++i)
2031 if (test_bit(i, info->strmap))
2032 *++s = mod->strtab[i];
2034 #else
2035 static inline void layout_symtab(struct module *mod, struct load_info *info)
2039 static void add_kallsyms(struct module *mod, struct load_info *info)
2042 #endif /* CONFIG_KALLSYMS */
2044 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2046 if (!debug)
2047 return;
2048 #ifdef CONFIG_DYNAMIC_DEBUG
2049 if (ddebug_add_module(debug, num, debug->modname))
2050 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2051 debug->modname);
2052 #endif
2055 static void dynamic_debug_remove(struct _ddebug *debug)
2057 if (debug)
2058 ddebug_remove_module(debug->modname);
2061 static void *module_alloc_update_bounds(unsigned long size)
2063 void *ret = module_alloc(size);
2065 if (ret) {
2066 mutex_lock(&module_mutex);
2067 /* Update module bounds. */
2068 if ((unsigned long)ret < module_addr_min)
2069 module_addr_min = (unsigned long)ret;
2070 if ((unsigned long)ret + size > module_addr_max)
2071 module_addr_max = (unsigned long)ret + size;
2072 mutex_unlock(&module_mutex);
2074 return ret;
2077 #ifdef CONFIG_DEBUG_KMEMLEAK
2078 static void kmemleak_load_module(const struct module *mod,
2079 const struct load_info *info)
2081 unsigned int i;
2083 /* only scan the sections containing data */
2084 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2086 for (i = 1; i < info->hdr->e_shnum; i++) {
2087 const char *name = info->secstrings + info->sechdrs[i].sh_name;
2088 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC))
2089 continue;
2090 if (!strstarts(name, ".data") && !strstarts(name, ".bss"))
2091 continue;
2093 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2094 info->sechdrs[i].sh_size, GFP_KERNEL);
2097 #else
2098 static inline void kmemleak_load_module(const struct module *mod,
2099 const struct load_info *info)
2102 #endif
2104 /* Sets info->hdr and info->len. */
2105 static int copy_and_check(struct load_info *info,
2106 const void __user *umod, unsigned long len,
2107 const char __user *uargs)
2109 int err;
2110 Elf_Ehdr *hdr;
2112 if (len < sizeof(*hdr))
2113 return -ENOEXEC;
2115 /* Suck in entire file: we'll want most of it. */
2116 /* vmalloc barfs on "unusual" numbers. Check here */
2117 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
2118 return -ENOMEM;
2120 if (copy_from_user(hdr, umod, len) != 0) {
2121 err = -EFAULT;
2122 goto free_hdr;
2125 /* Sanity checks against insmoding binaries or wrong arch,
2126 weird elf version */
2127 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
2128 || hdr->e_type != ET_REL
2129 || !elf_check_arch(hdr)
2130 || hdr->e_shentsize != sizeof(Elf_Shdr)) {
2131 err = -ENOEXEC;
2132 goto free_hdr;
2135 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
2136 err = -ENOEXEC;
2137 goto free_hdr;
2140 info->hdr = hdr;
2141 info->len = len;
2142 return 0;
2144 free_hdr:
2145 vfree(hdr);
2146 return err;
2149 static void free_copy(struct load_info *info)
2151 vfree(info->hdr);
2154 static int rewrite_section_headers(struct load_info *info)
2156 unsigned int i;
2158 /* This should always be true, but let's be sure. */
2159 info->sechdrs[0].sh_addr = 0;
2161 for (i = 1; i < info->hdr->e_shnum; i++) {
2162 Elf_Shdr *shdr = &info->sechdrs[i];
2163 if (shdr->sh_type != SHT_NOBITS
2164 && info->len < shdr->sh_offset + shdr->sh_size) {
2165 printk(KERN_ERR "Module len %lu truncated\n",
2166 info->len);
2167 return -ENOEXEC;
2170 /* Mark all sections sh_addr with their address in the
2171 temporary image. */
2172 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2174 #ifndef CONFIG_MODULE_UNLOAD
2175 /* Don't load .exit sections */
2176 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2177 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2178 #endif
2181 /* Track but don't keep modinfo and version sections. */
2182 info->index.vers = find_sec(info, "__versions");
2183 info->index.info = find_sec(info, ".modinfo");
2184 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2185 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2186 return 0;
2190 * Set up our basic convenience variables (pointers to section headers,
2191 * search for module section index etc), and do some basic section
2192 * verification.
2194 * Return the temporary module pointer (we'll replace it with the final
2195 * one when we move the module sections around).
2197 static struct module *setup_load_info(struct load_info *info)
2199 unsigned int i;
2200 int err;
2201 struct module *mod;
2203 /* Set up the convenience variables */
2204 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2205 info->secstrings = (void *)info->hdr
2206 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2208 err = rewrite_section_headers(info);
2209 if (err)
2210 return ERR_PTR(err);
2212 /* Find internal symbols and strings. */
2213 for (i = 1; i < info->hdr->e_shnum; i++) {
2214 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2215 info->index.sym = i;
2216 info->index.str = info->sechdrs[i].sh_link;
2217 info->strtab = (char *)info->hdr
2218 + info->sechdrs[info->index.str].sh_offset;
2219 break;
2223 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
2224 if (!info->index.mod) {
2225 printk(KERN_WARNING "No module found in object\n");
2226 return ERR_PTR(-ENOEXEC);
2228 /* This is temporary: point mod into copy of data. */
2229 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2231 if (info->index.sym == 0) {
2232 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2233 mod->name);
2234 return ERR_PTR(-ENOEXEC);
2237 info->index.pcpu = find_pcpusec(info);
2239 /* Check module struct version now, before we try to use module. */
2240 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2241 return ERR_PTR(-ENOEXEC);
2243 return mod;
2246 static int check_modinfo(struct module *mod, struct load_info *info)
2248 const char *modmagic = get_modinfo(info, "vermagic");
2249 int err;
2251 /* This is allowed: modprobe --force will invalidate it. */
2252 if (!modmagic) {
2253 err = try_to_force_load(mod, "bad vermagic");
2254 if (err)
2255 return err;
2256 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2257 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2258 mod->name, modmagic, vermagic);
2259 return -ENOEXEC;
2262 if (get_modinfo(info, "staging")) {
2263 add_taint_module(mod, TAINT_CRAP);
2264 printk(KERN_WARNING "%s: module is from the staging directory,"
2265 " the quality is unknown, you have been warned.\n",
2266 mod->name);
2269 /* Set up license info based on the info section */
2270 set_license(mod, get_modinfo(info, "license"));
2272 return 0;
2275 static void find_module_sections(struct module *mod, struct load_info *info)
2277 mod->kp = section_objs(info, "__param",
2278 sizeof(*mod->kp), &mod->num_kp);
2279 mod->syms = section_objs(info, "__ksymtab",
2280 sizeof(*mod->syms), &mod->num_syms);
2281 mod->crcs = section_addr(info, "__kcrctab");
2282 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2283 sizeof(*mod->gpl_syms),
2284 &mod->num_gpl_syms);
2285 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2286 mod->gpl_future_syms = section_objs(info,
2287 "__ksymtab_gpl_future",
2288 sizeof(*mod->gpl_future_syms),
2289 &mod->num_gpl_future_syms);
2290 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
2292 #ifdef CONFIG_UNUSED_SYMBOLS
2293 mod->unused_syms = section_objs(info, "__ksymtab_unused",
2294 sizeof(*mod->unused_syms),
2295 &mod->num_unused_syms);
2296 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2297 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
2298 sizeof(*mod->unused_gpl_syms),
2299 &mod->num_unused_gpl_syms);
2300 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
2301 #endif
2302 #ifdef CONFIG_CONSTRUCTORS
2303 mod->ctors = section_objs(info, ".ctors",
2304 sizeof(*mod->ctors), &mod->num_ctors);
2305 #endif
2307 #ifdef CONFIG_TRACEPOINTS
2308 mod->tracepoints = section_objs(info, "__tracepoints",
2309 sizeof(*mod->tracepoints),
2310 &mod->num_tracepoints);
2311 #endif
2312 #ifdef CONFIG_EVENT_TRACING
2313 mod->trace_events = section_objs(info, "_ftrace_events",
2314 sizeof(*mod->trace_events),
2315 &mod->num_trace_events);
2317 * This section contains pointers to allocated objects in the trace
2318 * code and not scanning it leads to false positives.
2320 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2321 mod->num_trace_events, GFP_KERNEL);
2322 #endif
2323 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2324 /* sechdrs[0].sh_size is always zero */
2325 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
2326 sizeof(*mod->ftrace_callsites),
2327 &mod->num_ftrace_callsites);
2328 #endif
2330 mod->extable = section_objs(info, "__ex_table",
2331 sizeof(*mod->extable), &mod->num_exentries);
2333 if (section_addr(info, "__obsparm"))
2334 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2335 mod->name);
2337 info->debug = section_objs(info, "__verbose",
2338 sizeof(*info->debug), &info->num_debug);
2341 static int move_module(struct module *mod, struct load_info *info)
2343 int i;
2344 void *ptr;
2346 /* Do the allocs. */
2347 ptr = module_alloc_update_bounds(mod->core_size);
2349 * The pointer to this block is stored in the module structure
2350 * which is inside the block. Just mark it as not being a
2351 * leak.
2353 kmemleak_not_leak(ptr);
2354 if (!ptr)
2355 return -ENOMEM;
2357 memset(ptr, 0, mod->core_size);
2358 mod->module_core = ptr;
2360 ptr = module_alloc_update_bounds(mod->init_size);
2362 * The pointer to this block is stored in the module structure
2363 * which is inside the block. This block doesn't need to be
2364 * scanned as it contains data and code that will be freed
2365 * after the module is initialized.
2367 kmemleak_ignore(ptr);
2368 if (!ptr && mod->init_size) {
2369 module_free(mod, mod->module_core);
2370 return -ENOMEM;
2372 memset(ptr, 0, mod->init_size);
2373 mod->module_init = ptr;
2375 /* Transfer each section which specifies SHF_ALLOC */
2376 DEBUGP("final section addresses:\n");
2377 for (i = 0; i < info->hdr->e_shnum; i++) {
2378 void *dest;
2379 Elf_Shdr *shdr = &info->sechdrs[i];
2381 if (!(shdr->sh_flags & SHF_ALLOC))
2382 continue;
2384 if (shdr->sh_entsize & INIT_OFFSET_MASK)
2385 dest = mod->module_init
2386 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
2387 else
2388 dest = mod->module_core + shdr->sh_entsize;
2390 if (shdr->sh_type != SHT_NOBITS)
2391 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2392 /* Update sh_addr to point to copy in image. */
2393 shdr->sh_addr = (unsigned long)dest;
2394 DEBUGP("\t0x%lx %s\n",
2395 shdr->sh_addr, info->secstrings + shdr->sh_name);
2398 return 0;
2401 static int check_module_license_and_versions(struct module *mod)
2404 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2405 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2406 * using GPL-only symbols it needs.
2408 if (strcmp(mod->name, "ndiswrapper") == 0)
2409 add_taint(TAINT_PROPRIETARY_MODULE);
2411 /* driverloader was caught wrongly pretending to be under GPL */
2412 if (strcmp(mod->name, "driverloader") == 0)
2413 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2415 #ifdef CONFIG_MODVERSIONS
2416 if ((mod->num_syms && !mod->crcs)
2417 || (mod->num_gpl_syms && !mod->gpl_crcs)
2418 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2419 #ifdef CONFIG_UNUSED_SYMBOLS
2420 || (mod->num_unused_syms && !mod->unused_crcs)
2421 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2422 #endif
2424 return try_to_force_load(mod,
2425 "no versions for exported symbols");
2427 #endif
2428 return 0;
2431 static void flush_module_icache(const struct module *mod)
2433 mm_segment_t old_fs;
2435 /* flush the icache in correct context */
2436 old_fs = get_fs();
2437 set_fs(KERNEL_DS);
2440 * Flush the instruction cache, since we've played with text.
2441 * Do it before processing of module parameters, so the module
2442 * can provide parameter accessor functions of its own.
2444 if (mod->module_init)
2445 flush_icache_range((unsigned long)mod->module_init,
2446 (unsigned long)mod->module_init
2447 + mod->init_size);
2448 flush_icache_range((unsigned long)mod->module_core,
2449 (unsigned long)mod->module_core + mod->core_size);
2451 set_fs(old_fs);
2454 static struct module *layout_and_allocate(struct load_info *info)
2456 /* Module within temporary copy. */
2457 struct module *mod;
2458 Elf_Shdr *pcpusec;
2459 int err;
2461 mod = setup_load_info(info);
2462 if (IS_ERR(mod))
2463 return mod;
2465 err = check_modinfo(mod, info);
2466 if (err)
2467 return ERR_PTR(err);
2469 /* Allow arches to frob section contents and sizes. */
2470 err = module_frob_arch_sections(info->hdr, info->sechdrs,
2471 info->secstrings, mod);
2472 if (err < 0)
2473 goto out;
2475 pcpusec = &info->sechdrs[info->index.pcpu];
2476 if (pcpusec->sh_size) {
2477 /* We have a special allocation for this section. */
2478 err = percpu_modalloc(mod,
2479 pcpusec->sh_size, pcpusec->sh_addralign);
2480 if (err)
2481 goto out;
2482 pcpusec->sh_flags &= ~(unsigned long)SHF_ALLOC;
2485 /* Determine total sizes, and put offsets in sh_entsize. For now
2486 this is done generically; there doesn't appear to be any
2487 special cases for the architectures. */
2488 layout_sections(mod, info);
2490 info->strmap = kzalloc(BITS_TO_LONGS(info->sechdrs[info->index.str].sh_size)
2491 * sizeof(long), GFP_KERNEL);
2492 if (!info->strmap) {
2493 err = -ENOMEM;
2494 goto free_percpu;
2496 layout_symtab(mod, info);
2498 /* Allocate and move to the final place */
2499 err = move_module(mod, info);
2500 if (err)
2501 goto free_strmap;
2503 /* Module has been copied to its final place now: return it. */
2504 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2505 kmemleak_load_module(mod, info);
2506 return mod;
2508 free_strmap:
2509 kfree(info->strmap);
2510 free_percpu:
2511 percpu_modfree(mod);
2512 out:
2513 return ERR_PTR(err);
2516 /* mod is no longer valid after this! */
2517 static void module_deallocate(struct module *mod, struct load_info *info)
2519 kfree(info->strmap);
2520 percpu_modfree(mod);
2521 module_free(mod, mod->module_init);
2522 module_free(mod, mod->module_core);
2525 static int post_relocation(struct module *mod, const struct load_info *info)
2527 /* Sort exception table now relocations are done. */
2528 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2530 /* Copy relocated percpu area over. */
2531 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
2532 info->sechdrs[info->index.pcpu].sh_size);
2534 /* Setup kallsyms-specific fields. */
2535 add_kallsyms(mod, info);
2537 /* Arch-specific module finalizing. */
2538 return module_finalize(info->hdr, info->sechdrs, mod);
2541 /* Allocate and load the module: note that size of section 0 is always
2542 zero, and we rely on this for optional sections. */
2543 static struct module *load_module(void __user *umod,
2544 unsigned long len,
2545 const char __user *uargs)
2547 struct load_info info = { NULL, };
2548 struct module *mod;
2549 long err;
2551 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2552 umod, len, uargs);
2554 /* Copy in the blobs from userspace, check they are vaguely sane. */
2555 err = copy_and_check(&info, umod, len, uargs);
2556 if (err)
2557 return ERR_PTR(err);
2559 /* Figure out module layout, and allocate all the memory. */
2560 mod = layout_and_allocate(&info);
2561 if (IS_ERR(mod)) {
2562 err = PTR_ERR(mod);
2563 goto free_copy;
2566 /* Now module is in final location, initialize linked lists, etc. */
2567 err = module_unload_init(mod);
2568 if (err)
2569 goto free_module;
2571 /* Now we've got everything in the final locations, we can
2572 * find optional sections. */
2573 find_module_sections(mod, &info);
2575 err = check_module_license_and_versions(mod);
2576 if (err)
2577 goto free_unload;
2579 /* Set up MODINFO_ATTR fields */
2580 setup_modinfo(mod, &info);
2582 /* Fix up syms, so that st_value is a pointer to location. */
2583 err = simplify_symbols(mod, &info);
2584 if (err < 0)
2585 goto free_modinfo;
2587 err = apply_relocations(mod, &info);
2588 if (err < 0)
2589 goto free_modinfo;
2591 err = post_relocation(mod, &info);
2592 if (err < 0)
2593 goto free_modinfo;
2595 flush_module_icache(mod);
2597 /* Now copy in args */
2598 mod->args = strndup_user(uargs, ~0UL >> 1);
2599 if (IS_ERR(mod->args)) {
2600 err = PTR_ERR(mod->args);
2601 goto free_arch_cleanup;
2604 /* Mark state as coming so strong_try_module_get() ignores us. */
2605 mod->state = MODULE_STATE_COMING;
2607 /* Now sew it into the lists so we can get lockdep and oops
2608 * info during argument parsing. Noone should access us, since
2609 * strong_try_module_get() will fail.
2610 * lockdep/oops can run asynchronous, so use the RCU list insertion
2611 * function to insert in a way safe to concurrent readers.
2612 * The mutex protects against concurrent writers.
2614 mutex_lock(&module_mutex);
2615 if (find_module(mod->name)) {
2616 err = -EEXIST;
2617 goto unlock;
2620 /* This has to be done once we're sure module name is unique. */
2621 if (!mod->taints)
2622 dynamic_debug_setup(info.debug, info.num_debug);
2624 /* Find duplicate symbols */
2625 err = verify_export_symbols(mod);
2626 if (err < 0)
2627 goto ddebug;
2629 module_bug_finalize(info.hdr, info.sechdrs, mod);
2630 list_add_rcu(&mod->list, &modules);
2631 mutex_unlock(&module_mutex);
2633 /* Module is ready to execute: parsing args may do that. */
2634 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2635 if (err < 0)
2636 goto unlink;
2638 /* Link in to syfs. */
2639 err = mod_sysfs_setup(mod, &info, mod->kp, mod->num_kp);
2640 if (err < 0)
2641 goto unlink;
2643 /* Get rid of temporary copy and strmap. */
2644 kfree(info.strmap);
2645 free_copy(&info);
2647 /* Done! */
2648 trace_module_load(mod);
2649 return mod;
2651 unlink:
2652 mutex_lock(&module_mutex);
2653 /* Unlink carefully: kallsyms could be walking list. */
2654 list_del_rcu(&mod->list);
2655 module_bug_cleanup(mod);
2657 ddebug:
2658 if (!mod->taints)
2659 dynamic_debug_remove(info.debug);
2660 unlock:
2661 mutex_unlock(&module_mutex);
2662 synchronize_sched();
2663 kfree(mod->args);
2664 free_arch_cleanup:
2665 module_arch_cleanup(mod);
2666 free_modinfo:
2667 free_modinfo(mod);
2668 free_unload:
2669 module_unload_free(mod);
2670 free_module:
2671 module_deallocate(mod, &info);
2672 free_copy:
2673 free_copy(&info);
2674 return ERR_PTR(err);
2677 /* Call module constructors. */
2678 static void do_mod_ctors(struct module *mod)
2680 #ifdef CONFIG_CONSTRUCTORS
2681 unsigned long i;
2683 for (i = 0; i < mod->num_ctors; i++)
2684 mod->ctors[i]();
2685 #endif
2688 /* This is where the real work happens */
2689 SYSCALL_DEFINE3(init_module, void __user *, umod,
2690 unsigned long, len, const char __user *, uargs)
2692 struct module *mod;
2693 int ret = 0;
2695 /* Must have permission */
2696 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2697 return -EPERM;
2699 /* Do all the hard work */
2700 mod = load_module(umod, len, uargs);
2701 if (IS_ERR(mod))
2702 return PTR_ERR(mod);
2704 blocking_notifier_call_chain(&module_notify_list,
2705 MODULE_STATE_COMING, mod);
2707 do_mod_ctors(mod);
2708 /* Start the module */
2709 if (mod->init != NULL)
2710 ret = do_one_initcall(mod->init);
2711 if (ret < 0) {
2712 /* Init routine failed: abort. Try to protect us from
2713 buggy refcounters. */
2714 mod->state = MODULE_STATE_GOING;
2715 synchronize_sched();
2716 module_put(mod);
2717 blocking_notifier_call_chain(&module_notify_list,
2718 MODULE_STATE_GOING, mod);
2719 free_module(mod);
2720 wake_up(&module_wq);
2721 return ret;
2723 if (ret > 0) {
2724 printk(KERN_WARNING
2725 "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2726 "%s: loading module anyway...\n",
2727 __func__, mod->name, ret,
2728 __func__);
2729 dump_stack();
2732 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2733 mod->state = MODULE_STATE_LIVE;
2734 wake_up(&module_wq);
2735 blocking_notifier_call_chain(&module_notify_list,
2736 MODULE_STATE_LIVE, mod);
2738 /* We need to finish all async code before the module init sequence is done */
2739 async_synchronize_full();
2741 mutex_lock(&module_mutex);
2742 /* Drop initial reference. */
2743 module_put(mod);
2744 trim_init_extable(mod);
2745 #ifdef CONFIG_KALLSYMS
2746 mod->num_symtab = mod->core_num_syms;
2747 mod->symtab = mod->core_symtab;
2748 mod->strtab = mod->core_strtab;
2749 #endif
2750 module_free(mod, mod->module_init);
2751 mod->module_init = NULL;
2752 mod->init_size = 0;
2753 mod->init_text_size = 0;
2754 mutex_unlock(&module_mutex);
2756 return 0;
2759 static inline int within(unsigned long addr, void *start, unsigned long size)
2761 return ((void *)addr >= start && (void *)addr < start + size);
2764 #ifdef CONFIG_KALLSYMS
2766 * This ignores the intensely annoying "mapping symbols" found
2767 * in ARM ELF files: $a, $t and $d.
2769 static inline int is_arm_mapping_symbol(const char *str)
2771 return str[0] == '$' && strchr("atd", str[1])
2772 && (str[2] == '\0' || str[2] == '.');
2775 static const char *get_ksymbol(struct module *mod,
2776 unsigned long addr,
2777 unsigned long *size,
2778 unsigned long *offset)
2780 unsigned int i, best = 0;
2781 unsigned long nextval;
2783 /* At worse, next value is at end of module */
2784 if (within_module_init(addr, mod))
2785 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2786 else
2787 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2789 /* Scan for closest preceeding symbol, and next symbol. (ELF
2790 starts real symbols at 1). */
2791 for (i = 1; i < mod->num_symtab; i++) {
2792 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2793 continue;
2795 /* We ignore unnamed symbols: they're uninformative
2796 * and inserted at a whim. */
2797 if (mod->symtab[i].st_value <= addr
2798 && mod->symtab[i].st_value > mod->symtab[best].st_value
2799 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2800 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2801 best = i;
2802 if (mod->symtab[i].st_value > addr
2803 && mod->symtab[i].st_value < nextval
2804 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2805 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2806 nextval = mod->symtab[i].st_value;
2809 if (!best)
2810 return NULL;
2812 if (size)
2813 *size = nextval - mod->symtab[best].st_value;
2814 if (offset)
2815 *offset = addr - mod->symtab[best].st_value;
2816 return mod->strtab + mod->symtab[best].st_name;
2819 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2820 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2821 const char *module_address_lookup(unsigned long addr,
2822 unsigned long *size,
2823 unsigned long *offset,
2824 char **modname,
2825 char *namebuf)
2827 struct module *mod;
2828 const char *ret = NULL;
2830 preempt_disable();
2831 list_for_each_entry_rcu(mod, &modules, list) {
2832 if (within_module_init(addr, mod) ||
2833 within_module_core(addr, mod)) {
2834 if (modname)
2835 *modname = mod->name;
2836 ret = get_ksymbol(mod, addr, size, offset);
2837 break;
2840 /* Make a copy in here where it's safe */
2841 if (ret) {
2842 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2843 ret = namebuf;
2845 preempt_enable();
2846 return ret;
2849 int lookup_module_symbol_name(unsigned long addr, char *symname)
2851 struct module *mod;
2853 preempt_disable();
2854 list_for_each_entry_rcu(mod, &modules, list) {
2855 if (within_module_init(addr, mod) ||
2856 within_module_core(addr, mod)) {
2857 const char *sym;
2859 sym = get_ksymbol(mod, addr, NULL, NULL);
2860 if (!sym)
2861 goto out;
2862 strlcpy(symname, sym, KSYM_NAME_LEN);
2863 preempt_enable();
2864 return 0;
2867 out:
2868 preempt_enable();
2869 return -ERANGE;
2872 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2873 unsigned long *offset, char *modname, char *name)
2875 struct module *mod;
2877 preempt_disable();
2878 list_for_each_entry_rcu(mod, &modules, list) {
2879 if (within_module_init(addr, mod) ||
2880 within_module_core(addr, mod)) {
2881 const char *sym;
2883 sym = get_ksymbol(mod, addr, size, offset);
2884 if (!sym)
2885 goto out;
2886 if (modname)
2887 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2888 if (name)
2889 strlcpy(name, sym, KSYM_NAME_LEN);
2890 preempt_enable();
2891 return 0;
2894 out:
2895 preempt_enable();
2896 return -ERANGE;
2899 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2900 char *name, char *module_name, int *exported)
2902 struct module *mod;
2904 preempt_disable();
2905 list_for_each_entry_rcu(mod, &modules, list) {
2906 if (symnum < mod->num_symtab) {
2907 *value = mod->symtab[symnum].st_value;
2908 *type = mod->symtab[symnum].st_info;
2909 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2910 KSYM_NAME_LEN);
2911 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2912 *exported = is_exported(name, *value, mod);
2913 preempt_enable();
2914 return 0;
2916 symnum -= mod->num_symtab;
2918 preempt_enable();
2919 return -ERANGE;
2922 static unsigned long mod_find_symname(struct module *mod, const char *name)
2924 unsigned int i;
2926 for (i = 0; i < mod->num_symtab; i++)
2927 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2928 mod->symtab[i].st_info != 'U')
2929 return mod->symtab[i].st_value;
2930 return 0;
2933 /* Look for this name: can be of form module:name. */
2934 unsigned long module_kallsyms_lookup_name(const char *name)
2936 struct module *mod;
2937 char *colon;
2938 unsigned long ret = 0;
2940 /* Don't lock: we're in enough trouble already. */
2941 preempt_disable();
2942 if ((colon = strchr(name, ':')) != NULL) {
2943 *colon = '\0';
2944 if ((mod = find_module(name)) != NULL)
2945 ret = mod_find_symname(mod, colon+1);
2946 *colon = ':';
2947 } else {
2948 list_for_each_entry_rcu(mod, &modules, list)
2949 if ((ret = mod_find_symname(mod, name)) != 0)
2950 break;
2952 preempt_enable();
2953 return ret;
2956 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
2957 struct module *, unsigned long),
2958 void *data)
2960 struct module *mod;
2961 unsigned int i;
2962 int ret;
2964 list_for_each_entry(mod, &modules, list) {
2965 for (i = 0; i < mod->num_symtab; i++) {
2966 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
2967 mod, mod->symtab[i].st_value);
2968 if (ret != 0)
2969 return ret;
2972 return 0;
2974 #endif /* CONFIG_KALLSYMS */
2976 static char *module_flags(struct module *mod, char *buf)
2978 int bx = 0;
2980 if (mod->taints ||
2981 mod->state == MODULE_STATE_GOING ||
2982 mod->state == MODULE_STATE_COMING) {
2983 buf[bx++] = '(';
2984 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2985 buf[bx++] = 'P';
2986 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2987 buf[bx++] = 'F';
2988 if (mod->taints & (1 << TAINT_CRAP))
2989 buf[bx++] = 'C';
2991 * TAINT_FORCED_RMMOD: could be added.
2992 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2993 * apply to modules.
2996 /* Show a - for module-is-being-unloaded */
2997 if (mod->state == MODULE_STATE_GOING)
2998 buf[bx++] = '-';
2999 /* Show a + for module-is-being-loaded */
3000 if (mod->state == MODULE_STATE_COMING)
3001 buf[bx++] = '+';
3002 buf[bx++] = ')';
3004 buf[bx] = '\0';
3006 return buf;
3009 #ifdef CONFIG_PROC_FS
3010 /* Called by the /proc file system to return a list of modules. */
3011 static void *m_start(struct seq_file *m, loff_t *pos)
3013 mutex_lock(&module_mutex);
3014 return seq_list_start(&modules, *pos);
3017 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3019 return seq_list_next(p, &modules, pos);
3022 static void m_stop(struct seq_file *m, void *p)
3024 mutex_unlock(&module_mutex);
3027 static int m_show(struct seq_file *m, void *p)
3029 struct module *mod = list_entry(p, struct module, list);
3030 char buf[8];
3032 seq_printf(m, "%s %u",
3033 mod->name, mod->init_size + mod->core_size);
3034 print_unload_info(m, mod);
3036 /* Informative for users. */
3037 seq_printf(m, " %s",
3038 mod->state == MODULE_STATE_GOING ? "Unloading":
3039 mod->state == MODULE_STATE_COMING ? "Loading":
3040 "Live");
3041 /* Used by oprofile and other similar tools. */
3042 seq_printf(m, " 0x%p", mod->module_core);
3044 /* Taints info */
3045 if (mod->taints)
3046 seq_printf(m, " %s", module_flags(mod, buf));
3048 seq_printf(m, "\n");
3049 return 0;
3052 /* Format: modulename size refcount deps address
3054 Where refcount is a number or -, and deps is a comma-separated list
3055 of depends or -.
3057 static const struct seq_operations modules_op = {
3058 .start = m_start,
3059 .next = m_next,
3060 .stop = m_stop,
3061 .show = m_show
3064 static int modules_open(struct inode *inode, struct file *file)
3066 return seq_open(file, &modules_op);
3069 static const struct file_operations proc_modules_operations = {
3070 .open = modules_open,
3071 .read = seq_read,
3072 .llseek = seq_lseek,
3073 .release = seq_release,
3076 static int __init proc_modules_init(void)
3078 proc_create("modules", 0, NULL, &proc_modules_operations);
3079 return 0;
3081 module_init(proc_modules_init);
3082 #endif
3084 /* Given an address, look for it in the module exception tables. */
3085 const struct exception_table_entry *search_module_extables(unsigned long addr)
3087 const struct exception_table_entry *e = NULL;
3088 struct module *mod;
3090 preempt_disable();
3091 list_for_each_entry_rcu(mod, &modules, list) {
3092 if (mod->num_exentries == 0)
3093 continue;
3095 e = search_extable(mod->extable,
3096 mod->extable + mod->num_exentries - 1,
3097 addr);
3098 if (e)
3099 break;
3101 preempt_enable();
3103 /* Now, if we found one, we are running inside it now, hence
3104 we cannot unload the module, hence no refcnt needed. */
3105 return e;
3109 * is_module_address - is this address inside a module?
3110 * @addr: the address to check.
3112 * See is_module_text_address() if you simply want to see if the address
3113 * is code (not data).
3115 bool is_module_address(unsigned long addr)
3117 bool ret;
3119 preempt_disable();
3120 ret = __module_address(addr) != NULL;
3121 preempt_enable();
3123 return ret;
3127 * __module_address - get the module which contains an address.
3128 * @addr: the address.
3130 * Must be called with preempt disabled or module mutex held so that
3131 * module doesn't get freed during this.
3133 struct module *__module_address(unsigned long addr)
3135 struct module *mod;
3137 if (addr < module_addr_min || addr > module_addr_max)
3138 return NULL;
3140 list_for_each_entry_rcu(mod, &modules, list)
3141 if (within_module_core(addr, mod)
3142 || within_module_init(addr, mod))
3143 return mod;
3144 return NULL;
3146 EXPORT_SYMBOL_GPL(__module_address);
3149 * is_module_text_address - is this address inside module code?
3150 * @addr: the address to check.
3152 * See is_module_address() if you simply want to see if the address is
3153 * anywhere in a module. See kernel_text_address() for testing if an
3154 * address corresponds to kernel or module code.
3156 bool is_module_text_address(unsigned long addr)
3158 bool ret;
3160 preempt_disable();
3161 ret = __module_text_address(addr) != NULL;
3162 preempt_enable();
3164 return ret;
3168 * __module_text_address - get the module whose code contains an address.
3169 * @addr: the address.
3171 * Must be called with preempt disabled or module mutex held so that
3172 * module doesn't get freed during this.
3174 struct module *__module_text_address(unsigned long addr)
3176 struct module *mod = __module_address(addr);
3177 if (mod) {
3178 /* Make sure it's within the text section. */
3179 if (!within(addr, mod->module_init, mod->init_text_size)
3180 && !within(addr, mod->module_core, mod->core_text_size))
3181 mod = NULL;
3183 return mod;
3185 EXPORT_SYMBOL_GPL(__module_text_address);
3187 /* Don't grab lock, we're oopsing. */
3188 void print_modules(void)
3190 struct module *mod;
3191 char buf[8];
3193 printk(KERN_DEFAULT "Modules linked in:");
3194 /* Most callers should already have preempt disabled, but make sure */
3195 preempt_disable();
3196 list_for_each_entry_rcu(mod, &modules, list)
3197 printk(" %s%s", mod->name, module_flags(mod, buf));
3198 preempt_enable();
3199 if (last_unloaded_module[0])
3200 printk(" [last unloaded: %s]", last_unloaded_module);
3201 printk("\n");
3204 #ifdef CONFIG_MODVERSIONS
3205 /* Generate the signature for all relevant module structures here.
3206 * If these change, we don't want to try to parse the module. */
3207 void module_layout(struct module *mod,
3208 struct modversion_info *ver,
3209 struct kernel_param *kp,
3210 struct kernel_symbol *ks,
3211 struct tracepoint *tp)
3214 EXPORT_SYMBOL(module_layout);
3215 #endif
3217 #ifdef CONFIG_TRACEPOINTS
3218 void module_update_tracepoints(void)
3220 struct module *mod;
3222 mutex_lock(&module_mutex);
3223 list_for_each_entry(mod, &modules, list)
3224 if (!mod->taints)
3225 tracepoint_update_probe_range(mod->tracepoints,
3226 mod->tracepoints + mod->num_tracepoints);
3227 mutex_unlock(&module_mutex);
3231 * Returns 0 if current not found.
3232 * Returns 1 if current found.
3234 int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3236 struct module *iter_mod;
3237 int found = 0;
3239 mutex_lock(&module_mutex);
3240 list_for_each_entry(iter_mod, &modules, list) {
3241 if (!iter_mod->taints) {
3243 * Sorted module list
3245 if (iter_mod < iter->module)
3246 continue;
3247 else if (iter_mod > iter->module)
3248 iter->tracepoint = NULL;
3249 found = tracepoint_get_iter_range(&iter->tracepoint,
3250 iter_mod->tracepoints,
3251 iter_mod->tracepoints
3252 + iter_mod->num_tracepoints);
3253 if (found) {
3254 iter->module = iter_mod;
3255 break;
3259 mutex_unlock(&module_mutex);
3260 return found;
3262 #endif