agp: kill agp_rebind_memory
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / kernel / module.c
blob437a74a7524a7f592f669dbdc91a6c90503959ae
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>
58 #include <linux/jump_label.h>
60 #define CREATE_TRACE_POINTS
61 #include <trace/events/module.h>
63 #if 0
64 #define DEBUGP printk
65 #else
66 #define DEBUGP(fmt , a...)
67 #endif
69 #ifndef ARCH_SHF_SMALL
70 #define ARCH_SHF_SMALL 0
71 #endif
73 /* If this is set, the section belongs in the init part of the module */
74 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
77 * Mutex protects:
78 * 1) List of modules (also safely readable with preempt_disable),
79 * 2) module_use links,
80 * 3) module_addr_min/module_addr_max.
81 * (delete uses stop_machine/add uses RCU list operations). */
82 DEFINE_MUTEX(module_mutex);
83 EXPORT_SYMBOL_GPL(module_mutex);
84 static LIST_HEAD(modules);
85 #ifdef CONFIG_KGDB_KDB
86 struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
87 #endif /* CONFIG_KGDB_KDB */
90 /* Block module loading/unloading? */
91 int modules_disabled = 0;
93 /* Waiting for a module to finish initializing? */
94 static DECLARE_WAIT_QUEUE_HEAD(module_wq);
96 static BLOCKING_NOTIFIER_HEAD(module_notify_list);
98 /* Bounds of module allocation, for speeding __module_address.
99 * Protected by module_mutex. */
100 static unsigned long module_addr_min = -1UL, module_addr_max = 0;
102 int register_module_notifier(struct notifier_block * nb)
104 return blocking_notifier_chain_register(&module_notify_list, nb);
106 EXPORT_SYMBOL(register_module_notifier);
108 int unregister_module_notifier(struct notifier_block * nb)
110 return blocking_notifier_chain_unregister(&module_notify_list, nb);
112 EXPORT_SYMBOL(unregister_module_notifier);
114 struct load_info {
115 Elf_Ehdr *hdr;
116 unsigned long len;
117 Elf_Shdr *sechdrs;
118 char *secstrings, *strtab;
119 unsigned long *strmap;
120 unsigned long symoffs, stroffs;
121 struct _ddebug *debug;
122 unsigned int num_debug;
123 struct {
124 unsigned int sym, str, mod, vers, info, pcpu;
125 } index;
128 /* We require a truly strong try_module_get(): 0 means failure due to
129 ongoing or failed initialization etc. */
130 static inline int strong_try_module_get(struct module *mod)
132 if (mod && mod->state == MODULE_STATE_COMING)
133 return -EBUSY;
134 if (try_module_get(mod))
135 return 0;
136 else
137 return -ENOENT;
140 static inline void add_taint_module(struct module *mod, unsigned flag)
142 add_taint(flag);
143 mod->taints |= (1U << flag);
147 * A thread that wants to hold a reference to a module only while it
148 * is running can call this to safely exit. nfsd and lockd use this.
150 void __module_put_and_exit(struct module *mod, long code)
152 module_put(mod);
153 do_exit(code);
155 EXPORT_SYMBOL(__module_put_and_exit);
157 /* Find a module section: 0 means not found. */
158 static unsigned int find_sec(const struct load_info *info, const char *name)
160 unsigned int i;
162 for (i = 1; i < info->hdr->e_shnum; i++) {
163 Elf_Shdr *shdr = &info->sechdrs[i];
164 /* Alloc bit cleared means "ignore it." */
165 if ((shdr->sh_flags & SHF_ALLOC)
166 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
167 return i;
169 return 0;
172 /* Find a module section, or NULL. */
173 static void *section_addr(const struct load_info *info, const char *name)
175 /* Section 0 has sh_addr 0. */
176 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
179 /* Find a module section, or NULL. Fill in number of "objects" in section. */
180 static void *section_objs(const struct load_info *info,
181 const char *name,
182 size_t object_size,
183 unsigned int *num)
185 unsigned int sec = find_sec(info, name);
187 /* Section 0 has sh_addr 0 and sh_size 0. */
188 *num = info->sechdrs[sec].sh_size / object_size;
189 return (void *)info->sechdrs[sec].sh_addr;
192 /* Provided by the linker */
193 extern const struct kernel_symbol __start___ksymtab[];
194 extern const struct kernel_symbol __stop___ksymtab[];
195 extern const struct kernel_symbol __start___ksymtab_gpl[];
196 extern const struct kernel_symbol __stop___ksymtab_gpl[];
197 extern const struct kernel_symbol __start___ksymtab_gpl_future[];
198 extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
199 extern const unsigned long __start___kcrctab[];
200 extern const unsigned long __start___kcrctab_gpl[];
201 extern const unsigned long __start___kcrctab_gpl_future[];
202 #ifdef CONFIG_UNUSED_SYMBOLS
203 extern const struct kernel_symbol __start___ksymtab_unused[];
204 extern const struct kernel_symbol __stop___ksymtab_unused[];
205 extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
206 extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
207 extern const unsigned long __start___kcrctab_unused[];
208 extern const unsigned long __start___kcrctab_unused_gpl[];
209 #endif
211 #ifndef CONFIG_MODVERSIONS
212 #define symversion(base, idx) NULL
213 #else
214 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
215 #endif
217 static bool each_symbol_in_section(const struct symsearch *arr,
218 unsigned int arrsize,
219 struct module *owner,
220 bool (*fn)(const struct symsearch *syms,
221 struct module *owner,
222 unsigned int symnum, void *data),
223 void *data)
225 unsigned int i, j;
227 for (j = 0; j < arrsize; j++) {
228 for (i = 0; i < arr[j].stop - arr[j].start; i++)
229 if (fn(&arr[j], owner, i, data))
230 return true;
233 return false;
236 /* Returns true as soon as fn returns true, otherwise false. */
237 bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
238 unsigned int symnum, void *data), void *data)
240 struct module *mod;
241 static const struct symsearch arr[] = {
242 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
243 NOT_GPL_ONLY, false },
244 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
245 __start___kcrctab_gpl,
246 GPL_ONLY, false },
247 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
248 __start___kcrctab_gpl_future,
249 WILL_BE_GPL_ONLY, false },
250 #ifdef CONFIG_UNUSED_SYMBOLS
251 { __start___ksymtab_unused, __stop___ksymtab_unused,
252 __start___kcrctab_unused,
253 NOT_GPL_ONLY, true },
254 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
255 __start___kcrctab_unused_gpl,
256 GPL_ONLY, true },
257 #endif
260 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
261 return true;
263 list_for_each_entry_rcu(mod, &modules, list) {
264 struct symsearch arr[] = {
265 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
266 NOT_GPL_ONLY, false },
267 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
268 mod->gpl_crcs,
269 GPL_ONLY, false },
270 { mod->gpl_future_syms,
271 mod->gpl_future_syms + mod->num_gpl_future_syms,
272 mod->gpl_future_crcs,
273 WILL_BE_GPL_ONLY, false },
274 #ifdef CONFIG_UNUSED_SYMBOLS
275 { mod->unused_syms,
276 mod->unused_syms + mod->num_unused_syms,
277 mod->unused_crcs,
278 NOT_GPL_ONLY, true },
279 { mod->unused_gpl_syms,
280 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
281 mod->unused_gpl_crcs,
282 GPL_ONLY, true },
283 #endif
286 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
287 return true;
289 return false;
291 EXPORT_SYMBOL_GPL(each_symbol);
293 struct find_symbol_arg {
294 /* Input */
295 const char *name;
296 bool gplok;
297 bool warn;
299 /* Output */
300 struct module *owner;
301 const unsigned long *crc;
302 const struct kernel_symbol *sym;
305 static bool find_symbol_in_section(const struct symsearch *syms,
306 struct module *owner,
307 unsigned int symnum, void *data)
309 struct find_symbol_arg *fsa = data;
311 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
312 return false;
314 if (!fsa->gplok) {
315 if (syms->licence == GPL_ONLY)
316 return false;
317 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
318 printk(KERN_WARNING "Symbol %s is being used "
319 "by a non-GPL module, which will not "
320 "be allowed in the future\n", fsa->name);
321 printk(KERN_WARNING "Please see the file "
322 "Documentation/feature-removal-schedule.txt "
323 "in the kernel source tree for more details.\n");
327 #ifdef CONFIG_UNUSED_SYMBOLS
328 if (syms->unused && fsa->warn) {
329 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
330 "however this module is using it.\n", fsa->name);
331 printk(KERN_WARNING
332 "This symbol will go away in the future.\n");
333 printk(KERN_WARNING
334 "Please evalute if this is the right api to use and if "
335 "it really is, submit a report the linux kernel "
336 "mailinglist together with submitting your code for "
337 "inclusion.\n");
339 #endif
341 fsa->owner = owner;
342 fsa->crc = symversion(syms->crcs, symnum);
343 fsa->sym = &syms->start[symnum];
344 return true;
347 /* Find a symbol and return it, along with, (optional) crc and
348 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
349 const struct kernel_symbol *find_symbol(const char *name,
350 struct module **owner,
351 const unsigned long **crc,
352 bool gplok,
353 bool warn)
355 struct find_symbol_arg fsa;
357 fsa.name = name;
358 fsa.gplok = gplok;
359 fsa.warn = warn;
361 if (each_symbol(find_symbol_in_section, &fsa)) {
362 if (owner)
363 *owner = fsa.owner;
364 if (crc)
365 *crc = fsa.crc;
366 return fsa.sym;
369 DEBUGP("Failed to find symbol %s\n", name);
370 return NULL;
372 EXPORT_SYMBOL_GPL(find_symbol);
374 /* Search for module by name: must hold module_mutex. */
375 struct module *find_module(const char *name)
377 struct module *mod;
379 list_for_each_entry(mod, &modules, list) {
380 if (strcmp(mod->name, name) == 0)
381 return mod;
383 return NULL;
385 EXPORT_SYMBOL_GPL(find_module);
387 #ifdef CONFIG_SMP
389 static inline void __percpu *mod_percpu(struct module *mod)
391 return mod->percpu;
394 static int percpu_modalloc(struct module *mod,
395 unsigned long size, unsigned long align)
397 if (align > PAGE_SIZE) {
398 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
399 mod->name, align, PAGE_SIZE);
400 align = PAGE_SIZE;
403 mod->percpu = __alloc_reserved_percpu(size, align);
404 if (!mod->percpu) {
405 printk(KERN_WARNING
406 "%s: Could not allocate %lu bytes percpu data\n",
407 mod->name, size);
408 return -ENOMEM;
410 mod->percpu_size = size;
411 return 0;
414 static void percpu_modfree(struct module *mod)
416 free_percpu(mod->percpu);
419 static unsigned int find_pcpusec(struct load_info *info)
421 return find_sec(info, ".data..percpu");
424 static void percpu_modcopy(struct module *mod,
425 const void *from, unsigned long size)
427 int cpu;
429 for_each_possible_cpu(cpu)
430 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
434 * is_module_percpu_address - test whether address is from module static percpu
435 * @addr: address to test
437 * Test whether @addr belongs to module static percpu area.
439 * RETURNS:
440 * %true if @addr is from module static percpu area
442 bool is_module_percpu_address(unsigned long addr)
444 struct module *mod;
445 unsigned int cpu;
447 preempt_disable();
449 list_for_each_entry_rcu(mod, &modules, list) {
450 if (!mod->percpu_size)
451 continue;
452 for_each_possible_cpu(cpu) {
453 void *start = per_cpu_ptr(mod->percpu, cpu);
455 if ((void *)addr >= start &&
456 (void *)addr < start + mod->percpu_size) {
457 preempt_enable();
458 return true;
463 preempt_enable();
464 return false;
467 #else /* ... !CONFIG_SMP */
469 static inline void __percpu *mod_percpu(struct module *mod)
471 return NULL;
473 static inline int percpu_modalloc(struct module *mod,
474 unsigned long size, unsigned long align)
476 return -ENOMEM;
478 static inline void percpu_modfree(struct module *mod)
481 static unsigned int find_pcpusec(struct load_info *info)
483 return 0;
485 static inline void percpu_modcopy(struct module *mod,
486 const void *from, unsigned long size)
488 /* pcpusec should be 0, and size of that section should be 0. */
489 BUG_ON(size != 0);
491 bool is_module_percpu_address(unsigned long addr)
493 return false;
496 #endif /* CONFIG_SMP */
498 #define MODINFO_ATTR(field) \
499 static void setup_modinfo_##field(struct module *mod, const char *s) \
501 mod->field = kstrdup(s, GFP_KERNEL); \
503 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
504 struct module *mod, char *buffer) \
506 return sprintf(buffer, "%s\n", mod->field); \
508 static int modinfo_##field##_exists(struct module *mod) \
510 return mod->field != NULL; \
512 static void free_modinfo_##field(struct module *mod) \
514 kfree(mod->field); \
515 mod->field = NULL; \
517 static struct module_attribute modinfo_##field = { \
518 .attr = { .name = __stringify(field), .mode = 0444 }, \
519 .show = show_modinfo_##field, \
520 .setup = setup_modinfo_##field, \
521 .test = modinfo_##field##_exists, \
522 .free = free_modinfo_##field, \
525 MODINFO_ATTR(version);
526 MODINFO_ATTR(srcversion);
528 static char last_unloaded_module[MODULE_NAME_LEN+1];
530 #ifdef CONFIG_MODULE_UNLOAD
532 EXPORT_TRACEPOINT_SYMBOL(module_get);
534 /* Init the unload section of the module. */
535 static int module_unload_init(struct module *mod)
537 mod->refptr = alloc_percpu(struct module_ref);
538 if (!mod->refptr)
539 return -ENOMEM;
541 INIT_LIST_HEAD(&mod->source_list);
542 INIT_LIST_HEAD(&mod->target_list);
544 /* Hold reference count during initialization. */
545 __this_cpu_write(mod->refptr->incs, 1);
546 /* Backwards compatibility macros put refcount during init. */
547 mod->waiter = current;
549 return 0;
552 /* Does a already use b? */
553 static int already_uses(struct module *a, struct module *b)
555 struct module_use *use;
557 list_for_each_entry(use, &b->source_list, source_list) {
558 if (use->source == a) {
559 DEBUGP("%s uses %s!\n", a->name, b->name);
560 return 1;
563 DEBUGP("%s does not use %s!\n", a->name, b->name);
564 return 0;
568 * Module a uses b
569 * - we add 'a' as a "source", 'b' as a "target" of module use
570 * - the module_use is added to the list of 'b' sources (so
571 * 'b' can walk the list to see who sourced them), and of 'a'
572 * targets (so 'a' can see what modules it targets).
574 static int add_module_usage(struct module *a, struct module *b)
576 struct module_use *use;
578 DEBUGP("Allocating new usage for %s.\n", a->name);
579 use = kmalloc(sizeof(*use), GFP_ATOMIC);
580 if (!use) {
581 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
582 return -ENOMEM;
585 use->source = a;
586 use->target = b;
587 list_add(&use->source_list, &b->source_list);
588 list_add(&use->target_list, &a->target_list);
589 return 0;
592 /* Module a uses b: caller needs module_mutex() */
593 int ref_module(struct module *a, struct module *b)
595 int err;
597 if (b == NULL || already_uses(a, b))
598 return 0;
600 /* If module isn't available, we fail. */
601 err = strong_try_module_get(b);
602 if (err)
603 return err;
605 err = add_module_usage(a, b);
606 if (err) {
607 module_put(b);
608 return err;
610 return 0;
612 EXPORT_SYMBOL_GPL(ref_module);
614 /* Clear the unload stuff of the module. */
615 static void module_unload_free(struct module *mod)
617 struct module_use *use, *tmp;
619 mutex_lock(&module_mutex);
620 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
621 struct module *i = use->target;
622 DEBUGP("%s unusing %s\n", mod->name, i->name);
623 module_put(i);
624 list_del(&use->source_list);
625 list_del(&use->target_list);
626 kfree(use);
628 mutex_unlock(&module_mutex);
630 free_percpu(mod->refptr);
633 #ifdef CONFIG_MODULE_FORCE_UNLOAD
634 static inline int try_force_unload(unsigned int flags)
636 int ret = (flags & O_TRUNC);
637 if (ret)
638 add_taint(TAINT_FORCED_RMMOD);
639 return ret;
641 #else
642 static inline int try_force_unload(unsigned int flags)
644 return 0;
646 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
648 struct stopref
650 struct module *mod;
651 int flags;
652 int *forced;
655 /* Whole machine is stopped with interrupts off when this runs. */
656 static int __try_stop_module(void *_sref)
658 struct stopref *sref = _sref;
660 /* If it's not unused, quit unless we're forcing. */
661 if (module_refcount(sref->mod) != 0) {
662 if (!(*sref->forced = try_force_unload(sref->flags)))
663 return -EWOULDBLOCK;
666 /* Mark it as dying. */
667 sref->mod->state = MODULE_STATE_GOING;
668 return 0;
671 static int try_stop_module(struct module *mod, int flags, int *forced)
673 if (flags & O_NONBLOCK) {
674 struct stopref sref = { mod, flags, forced };
676 return stop_machine(__try_stop_module, &sref, NULL);
677 } else {
678 /* We don't need to stop the machine for this. */
679 mod->state = MODULE_STATE_GOING;
680 synchronize_sched();
681 return 0;
685 unsigned int module_refcount(struct module *mod)
687 unsigned int incs = 0, decs = 0;
688 int cpu;
690 for_each_possible_cpu(cpu)
691 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
693 * ensure the incs are added up after the decs.
694 * module_put ensures incs are visible before decs with smp_wmb.
696 * This 2-count scheme avoids the situation where the refcount
697 * for CPU0 is read, then CPU0 increments the module refcount,
698 * then CPU1 drops that refcount, then the refcount for CPU1 is
699 * read. We would record a decrement but not its corresponding
700 * increment so we would see a low count (disaster).
702 * Rare situation? But module_refcount can be preempted, and we
703 * might be tallying up 4096+ CPUs. So it is not impossible.
705 smp_rmb();
706 for_each_possible_cpu(cpu)
707 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
708 return incs - decs;
710 EXPORT_SYMBOL(module_refcount);
712 /* This exists whether we can unload or not */
713 static void free_module(struct module *mod);
715 static void wait_for_zero_refcount(struct module *mod)
717 /* Since we might sleep for some time, release the mutex first */
718 mutex_unlock(&module_mutex);
719 for (;;) {
720 DEBUGP("Looking at refcount...\n");
721 set_current_state(TASK_UNINTERRUPTIBLE);
722 if (module_refcount(mod) == 0)
723 break;
724 schedule();
726 current->state = TASK_RUNNING;
727 mutex_lock(&module_mutex);
730 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
731 unsigned int, flags)
733 struct module *mod;
734 char name[MODULE_NAME_LEN];
735 int ret, forced = 0;
737 if (!capable(CAP_SYS_MODULE) || modules_disabled)
738 return -EPERM;
740 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
741 return -EFAULT;
742 name[MODULE_NAME_LEN-1] = '\0';
744 if (mutex_lock_interruptible(&module_mutex) != 0)
745 return -EINTR;
747 mod = find_module(name);
748 if (!mod) {
749 ret = -ENOENT;
750 goto out;
753 if (!list_empty(&mod->source_list)) {
754 /* Other modules depend on us: get rid of them first. */
755 ret = -EWOULDBLOCK;
756 goto out;
759 /* Doing init or already dying? */
760 if (mod->state != MODULE_STATE_LIVE) {
761 /* FIXME: if (force), slam module count and wake up
762 waiter --RR */
763 DEBUGP("%s already dying\n", mod->name);
764 ret = -EBUSY;
765 goto out;
768 /* If it has an init func, it must have an exit func to unload */
769 if (mod->init && !mod->exit) {
770 forced = try_force_unload(flags);
771 if (!forced) {
772 /* This module can't be removed */
773 ret = -EBUSY;
774 goto out;
778 /* Set this up before setting mod->state */
779 mod->waiter = current;
781 /* Stop the machine so refcounts can't move and disable module. */
782 ret = try_stop_module(mod, flags, &forced);
783 if (ret != 0)
784 goto out;
786 /* Never wait if forced. */
787 if (!forced && module_refcount(mod) != 0)
788 wait_for_zero_refcount(mod);
790 mutex_unlock(&module_mutex);
791 /* Final destruction now noone is using it. */
792 if (mod->exit != NULL)
793 mod->exit();
794 blocking_notifier_call_chain(&module_notify_list,
795 MODULE_STATE_GOING, mod);
796 async_synchronize_full();
798 /* Store the name of the last unloaded module for diagnostic purposes */
799 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
801 free_module(mod);
802 return 0;
803 out:
804 mutex_unlock(&module_mutex);
805 return ret;
808 static inline void print_unload_info(struct seq_file *m, struct module *mod)
810 struct module_use *use;
811 int printed_something = 0;
813 seq_printf(m, " %u ", module_refcount(mod));
815 /* Always include a trailing , so userspace can differentiate
816 between this and the old multi-field proc format. */
817 list_for_each_entry(use, &mod->source_list, source_list) {
818 printed_something = 1;
819 seq_printf(m, "%s,", use->source->name);
822 if (mod->init != NULL && mod->exit == NULL) {
823 printed_something = 1;
824 seq_printf(m, "[permanent],");
827 if (!printed_something)
828 seq_printf(m, "-");
831 void __symbol_put(const char *symbol)
833 struct module *owner;
835 preempt_disable();
836 if (!find_symbol(symbol, &owner, NULL, true, false))
837 BUG();
838 module_put(owner);
839 preempt_enable();
841 EXPORT_SYMBOL(__symbol_put);
843 /* Note this assumes addr is a function, which it currently always is. */
844 void symbol_put_addr(void *addr)
846 struct module *modaddr;
847 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
849 if (core_kernel_text(a))
850 return;
852 /* module_text_address is safe here: we're supposed to have reference
853 * to module from symbol_get, so it can't go away. */
854 modaddr = __module_text_address(a);
855 BUG_ON(!modaddr);
856 module_put(modaddr);
858 EXPORT_SYMBOL_GPL(symbol_put_addr);
860 static ssize_t show_refcnt(struct module_attribute *mattr,
861 struct module *mod, char *buffer)
863 return sprintf(buffer, "%u\n", module_refcount(mod));
866 static struct module_attribute refcnt = {
867 .attr = { .name = "refcnt", .mode = 0444 },
868 .show = show_refcnt,
871 void module_put(struct module *module)
873 if (module) {
874 preempt_disable();
875 smp_wmb(); /* see comment in module_refcount */
876 __this_cpu_inc(module->refptr->decs);
878 trace_module_put(module, _RET_IP_);
879 /* Maybe they're waiting for us to drop reference? */
880 if (unlikely(!module_is_live(module)))
881 wake_up_process(module->waiter);
882 preempt_enable();
885 EXPORT_SYMBOL(module_put);
887 #else /* !CONFIG_MODULE_UNLOAD */
888 static inline void print_unload_info(struct seq_file *m, struct module *mod)
890 /* We don't know the usage count, or what modules are using. */
891 seq_printf(m, " - -");
894 static inline void module_unload_free(struct module *mod)
898 int ref_module(struct module *a, struct module *b)
900 return strong_try_module_get(b);
902 EXPORT_SYMBOL_GPL(ref_module);
904 static inline int module_unload_init(struct module *mod)
906 return 0;
908 #endif /* CONFIG_MODULE_UNLOAD */
910 static ssize_t show_initstate(struct module_attribute *mattr,
911 struct module *mod, char *buffer)
913 const char *state = "unknown";
915 switch (mod->state) {
916 case MODULE_STATE_LIVE:
917 state = "live";
918 break;
919 case MODULE_STATE_COMING:
920 state = "coming";
921 break;
922 case MODULE_STATE_GOING:
923 state = "going";
924 break;
926 return sprintf(buffer, "%s\n", state);
929 static struct module_attribute initstate = {
930 .attr = { .name = "initstate", .mode = 0444 },
931 .show = show_initstate,
934 static struct module_attribute *modinfo_attrs[] = {
935 &modinfo_version,
936 &modinfo_srcversion,
937 &initstate,
938 #ifdef CONFIG_MODULE_UNLOAD
939 &refcnt,
940 #endif
941 NULL,
944 static const char vermagic[] = VERMAGIC_STRING;
946 static int try_to_force_load(struct module *mod, const char *reason)
948 #ifdef CONFIG_MODULE_FORCE_LOAD
949 if (!test_taint(TAINT_FORCED_MODULE))
950 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
951 mod->name, reason);
952 add_taint_module(mod, TAINT_FORCED_MODULE);
953 return 0;
954 #else
955 return -ENOEXEC;
956 #endif
959 #ifdef CONFIG_MODVERSIONS
960 /* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
961 static unsigned long maybe_relocated(unsigned long crc,
962 const struct module *crc_owner)
964 #ifdef ARCH_RELOCATES_KCRCTAB
965 if (crc_owner == NULL)
966 return crc - (unsigned long)reloc_start;
967 #endif
968 return crc;
971 static int check_version(Elf_Shdr *sechdrs,
972 unsigned int versindex,
973 const char *symname,
974 struct module *mod,
975 const unsigned long *crc,
976 const struct module *crc_owner)
978 unsigned int i, num_versions;
979 struct modversion_info *versions;
981 /* Exporting module didn't supply crcs? OK, we're already tainted. */
982 if (!crc)
983 return 1;
985 /* No versions at all? modprobe --force does this. */
986 if (versindex == 0)
987 return try_to_force_load(mod, symname) == 0;
989 versions = (void *) sechdrs[versindex].sh_addr;
990 num_versions = sechdrs[versindex].sh_size
991 / sizeof(struct modversion_info);
993 for (i = 0; i < num_versions; i++) {
994 if (strcmp(versions[i].name, symname) != 0)
995 continue;
997 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
998 return 1;
999 DEBUGP("Found checksum %lX vs module %lX\n",
1000 maybe_relocated(*crc, crc_owner), versions[i].crc);
1001 goto bad_version;
1004 printk(KERN_WARNING "%s: no symbol version for %s\n",
1005 mod->name, symname);
1006 return 0;
1008 bad_version:
1009 printk("%s: disagrees about version of symbol %s\n",
1010 mod->name, symname);
1011 return 0;
1014 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1015 unsigned int versindex,
1016 struct module *mod)
1018 const unsigned long *crc;
1020 /* Since this should be found in kernel (which can't be removed),
1021 * no locking is necessary. */
1022 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1023 &crc, true, false))
1024 BUG();
1025 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1026 NULL);
1029 /* First part is kernel version, which we ignore if module has crcs. */
1030 static inline int same_magic(const char *amagic, const char *bmagic,
1031 bool has_crcs)
1033 if (has_crcs) {
1034 amagic += strcspn(amagic, " ");
1035 bmagic += strcspn(bmagic, " ");
1037 return strcmp(amagic, bmagic) == 0;
1039 #else
1040 static inline int check_version(Elf_Shdr *sechdrs,
1041 unsigned int versindex,
1042 const char *symname,
1043 struct module *mod,
1044 const unsigned long *crc,
1045 const struct module *crc_owner)
1047 return 1;
1050 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1051 unsigned int versindex,
1052 struct module *mod)
1054 return 1;
1057 static inline int same_magic(const char *amagic, const char *bmagic,
1058 bool has_crcs)
1060 return strcmp(amagic, bmagic) == 0;
1062 #endif /* CONFIG_MODVERSIONS */
1064 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1065 static const struct kernel_symbol *resolve_symbol(struct module *mod,
1066 const struct load_info *info,
1067 const char *name,
1068 char ownername[])
1070 struct module *owner;
1071 const struct kernel_symbol *sym;
1072 const unsigned long *crc;
1073 int err;
1075 mutex_lock(&module_mutex);
1076 sym = find_symbol(name, &owner, &crc,
1077 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1078 if (!sym)
1079 goto unlock;
1081 if (!check_version(info->sechdrs, info->index.vers, name, mod, crc,
1082 owner)) {
1083 sym = ERR_PTR(-EINVAL);
1084 goto getname;
1087 err = ref_module(mod, owner);
1088 if (err) {
1089 sym = ERR_PTR(err);
1090 goto getname;
1093 getname:
1094 /* We must make copy under the lock if we failed to get ref. */
1095 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1096 unlock:
1097 mutex_unlock(&module_mutex);
1098 return sym;
1101 static const struct kernel_symbol *
1102 resolve_symbol_wait(struct module *mod,
1103 const struct load_info *info,
1104 const char *name)
1106 const struct kernel_symbol *ksym;
1107 char owner[MODULE_NAME_LEN];
1109 if (wait_event_interruptible_timeout(module_wq,
1110 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1111 || PTR_ERR(ksym) != -EBUSY,
1112 30 * HZ) <= 0) {
1113 printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
1114 mod->name, owner);
1116 return ksym;
1120 * /sys/module/foo/sections stuff
1121 * J. Corbet <corbet@lwn.net>
1123 #ifdef CONFIG_SYSFS
1125 #ifdef CONFIG_KALLSYMS
1126 static inline bool sect_empty(const Elf_Shdr *sect)
1128 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1131 struct module_sect_attr
1133 struct module_attribute mattr;
1134 char *name;
1135 unsigned long address;
1138 struct module_sect_attrs
1140 struct attribute_group grp;
1141 unsigned int nsections;
1142 struct module_sect_attr attrs[0];
1145 static ssize_t module_sect_show(struct module_attribute *mattr,
1146 struct module *mod, char *buf)
1148 struct module_sect_attr *sattr =
1149 container_of(mattr, struct module_sect_attr, mattr);
1150 return sprintf(buf, "0x%lx\n", sattr->address);
1153 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1155 unsigned int section;
1157 for (section = 0; section < sect_attrs->nsections; section++)
1158 kfree(sect_attrs->attrs[section].name);
1159 kfree(sect_attrs);
1162 static void add_sect_attrs(struct module *mod, const struct load_info *info)
1164 unsigned int nloaded = 0, i, size[2];
1165 struct module_sect_attrs *sect_attrs;
1166 struct module_sect_attr *sattr;
1167 struct attribute **gattr;
1169 /* Count loaded sections and allocate structures */
1170 for (i = 0; i < info->hdr->e_shnum; i++)
1171 if (!sect_empty(&info->sechdrs[i]))
1172 nloaded++;
1173 size[0] = ALIGN(sizeof(*sect_attrs)
1174 + nloaded * sizeof(sect_attrs->attrs[0]),
1175 sizeof(sect_attrs->grp.attrs[0]));
1176 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1177 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1178 if (sect_attrs == NULL)
1179 return;
1181 /* Setup section attributes. */
1182 sect_attrs->grp.name = "sections";
1183 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1185 sect_attrs->nsections = 0;
1186 sattr = &sect_attrs->attrs[0];
1187 gattr = &sect_attrs->grp.attrs[0];
1188 for (i = 0; i < info->hdr->e_shnum; i++) {
1189 Elf_Shdr *sec = &info->sechdrs[i];
1190 if (sect_empty(sec))
1191 continue;
1192 sattr->address = sec->sh_addr;
1193 sattr->name = kstrdup(info->secstrings + sec->sh_name,
1194 GFP_KERNEL);
1195 if (sattr->name == NULL)
1196 goto out;
1197 sect_attrs->nsections++;
1198 sysfs_attr_init(&sattr->mattr.attr);
1199 sattr->mattr.show = module_sect_show;
1200 sattr->mattr.store = NULL;
1201 sattr->mattr.attr.name = sattr->name;
1202 sattr->mattr.attr.mode = S_IRUGO;
1203 *(gattr++) = &(sattr++)->mattr.attr;
1205 *gattr = NULL;
1207 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1208 goto out;
1210 mod->sect_attrs = sect_attrs;
1211 return;
1212 out:
1213 free_sect_attrs(sect_attrs);
1216 static void remove_sect_attrs(struct module *mod)
1218 if (mod->sect_attrs) {
1219 sysfs_remove_group(&mod->mkobj.kobj,
1220 &mod->sect_attrs->grp);
1221 /* We are positive that no one is using any sect attrs
1222 * at this point. Deallocate immediately. */
1223 free_sect_attrs(mod->sect_attrs);
1224 mod->sect_attrs = NULL;
1229 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1232 struct module_notes_attrs {
1233 struct kobject *dir;
1234 unsigned int notes;
1235 struct bin_attribute attrs[0];
1238 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
1239 struct bin_attribute *bin_attr,
1240 char *buf, loff_t pos, size_t count)
1243 * The caller checked the pos and count against our size.
1245 memcpy(buf, bin_attr->private + pos, count);
1246 return count;
1249 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1250 unsigned int i)
1252 if (notes_attrs->dir) {
1253 while (i-- > 0)
1254 sysfs_remove_bin_file(notes_attrs->dir,
1255 &notes_attrs->attrs[i]);
1256 kobject_put(notes_attrs->dir);
1258 kfree(notes_attrs);
1261 static void add_notes_attrs(struct module *mod, const struct load_info *info)
1263 unsigned int notes, loaded, i;
1264 struct module_notes_attrs *notes_attrs;
1265 struct bin_attribute *nattr;
1267 /* failed to create section attributes, so can't create notes */
1268 if (!mod->sect_attrs)
1269 return;
1271 /* Count notes sections and allocate structures. */
1272 notes = 0;
1273 for (i = 0; i < info->hdr->e_shnum; i++)
1274 if (!sect_empty(&info->sechdrs[i]) &&
1275 (info->sechdrs[i].sh_type == SHT_NOTE))
1276 ++notes;
1278 if (notes == 0)
1279 return;
1281 notes_attrs = kzalloc(sizeof(*notes_attrs)
1282 + notes * sizeof(notes_attrs->attrs[0]),
1283 GFP_KERNEL);
1284 if (notes_attrs == NULL)
1285 return;
1287 notes_attrs->notes = notes;
1288 nattr = &notes_attrs->attrs[0];
1289 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1290 if (sect_empty(&info->sechdrs[i]))
1291 continue;
1292 if (info->sechdrs[i].sh_type == SHT_NOTE) {
1293 sysfs_bin_attr_init(nattr);
1294 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1295 nattr->attr.mode = S_IRUGO;
1296 nattr->size = info->sechdrs[i].sh_size;
1297 nattr->private = (void *) info->sechdrs[i].sh_addr;
1298 nattr->read = module_notes_read;
1299 ++nattr;
1301 ++loaded;
1304 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
1305 if (!notes_attrs->dir)
1306 goto out;
1308 for (i = 0; i < notes; ++i)
1309 if (sysfs_create_bin_file(notes_attrs->dir,
1310 &notes_attrs->attrs[i]))
1311 goto out;
1313 mod->notes_attrs = notes_attrs;
1314 return;
1316 out:
1317 free_notes_attrs(notes_attrs, i);
1320 static void remove_notes_attrs(struct module *mod)
1322 if (mod->notes_attrs)
1323 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1326 #else
1328 static inline void add_sect_attrs(struct module *mod,
1329 const struct load_info *info)
1333 static inline void remove_sect_attrs(struct module *mod)
1337 static inline void add_notes_attrs(struct module *mod,
1338 const struct load_info *info)
1342 static inline void remove_notes_attrs(struct module *mod)
1345 #endif /* CONFIG_KALLSYMS */
1347 static void add_usage_links(struct module *mod)
1349 #ifdef CONFIG_MODULE_UNLOAD
1350 struct module_use *use;
1351 int nowarn;
1353 mutex_lock(&module_mutex);
1354 list_for_each_entry(use, &mod->target_list, target_list) {
1355 nowarn = sysfs_create_link(use->target->holders_dir,
1356 &mod->mkobj.kobj, mod->name);
1358 mutex_unlock(&module_mutex);
1359 #endif
1362 static void del_usage_links(struct module *mod)
1364 #ifdef CONFIG_MODULE_UNLOAD
1365 struct module_use *use;
1367 mutex_lock(&module_mutex);
1368 list_for_each_entry(use, &mod->target_list, target_list)
1369 sysfs_remove_link(use->target->holders_dir, mod->name);
1370 mutex_unlock(&module_mutex);
1371 #endif
1374 static int module_add_modinfo_attrs(struct module *mod)
1376 struct module_attribute *attr;
1377 struct module_attribute *temp_attr;
1378 int error = 0;
1379 int i;
1381 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1382 (ARRAY_SIZE(modinfo_attrs) + 1)),
1383 GFP_KERNEL);
1384 if (!mod->modinfo_attrs)
1385 return -ENOMEM;
1387 temp_attr = mod->modinfo_attrs;
1388 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1389 if (!attr->test ||
1390 (attr->test && attr->test(mod))) {
1391 memcpy(temp_attr, attr, sizeof(*temp_attr));
1392 sysfs_attr_init(&temp_attr->attr);
1393 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1394 ++temp_attr;
1397 return error;
1400 static void module_remove_modinfo_attrs(struct module *mod)
1402 struct module_attribute *attr;
1403 int i;
1405 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1406 /* pick a field to test for end of list */
1407 if (!attr->attr.name)
1408 break;
1409 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1410 if (attr->free)
1411 attr->free(mod);
1413 kfree(mod->modinfo_attrs);
1416 static int mod_sysfs_init(struct module *mod)
1418 int err;
1419 struct kobject *kobj;
1421 if (!module_sysfs_initialized) {
1422 printk(KERN_ERR "%s: module sysfs not initialized\n",
1423 mod->name);
1424 err = -EINVAL;
1425 goto out;
1428 kobj = kset_find_obj(module_kset, mod->name);
1429 if (kobj) {
1430 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1431 kobject_put(kobj);
1432 err = -EINVAL;
1433 goto out;
1436 mod->mkobj.mod = mod;
1438 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1439 mod->mkobj.kobj.kset = module_kset;
1440 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1441 "%s", mod->name);
1442 if (err)
1443 kobject_put(&mod->mkobj.kobj);
1445 /* delay uevent until full sysfs population */
1446 out:
1447 return err;
1450 static int mod_sysfs_setup(struct module *mod,
1451 const struct load_info *info,
1452 struct kernel_param *kparam,
1453 unsigned int num_params)
1455 int err;
1457 err = mod_sysfs_init(mod);
1458 if (err)
1459 goto out;
1461 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1462 if (!mod->holders_dir) {
1463 err = -ENOMEM;
1464 goto out_unreg;
1467 err = module_param_sysfs_setup(mod, kparam, num_params);
1468 if (err)
1469 goto out_unreg_holders;
1471 err = module_add_modinfo_attrs(mod);
1472 if (err)
1473 goto out_unreg_param;
1475 add_usage_links(mod);
1476 add_sect_attrs(mod, info);
1477 add_notes_attrs(mod, info);
1479 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
1480 return 0;
1482 out_unreg_param:
1483 module_param_sysfs_remove(mod);
1484 out_unreg_holders:
1485 kobject_put(mod->holders_dir);
1486 out_unreg:
1487 kobject_put(&mod->mkobj.kobj);
1488 out:
1489 return err;
1492 static void mod_sysfs_fini(struct module *mod)
1494 remove_notes_attrs(mod);
1495 remove_sect_attrs(mod);
1496 kobject_put(&mod->mkobj.kobj);
1499 #else /* !CONFIG_SYSFS */
1501 static int mod_sysfs_setup(struct module *mod,
1502 const struct load_info *info,
1503 struct kernel_param *kparam,
1504 unsigned int num_params)
1506 return 0;
1509 static void mod_sysfs_fini(struct module *mod)
1513 static void module_remove_modinfo_attrs(struct module *mod)
1517 static void del_usage_links(struct module *mod)
1521 #endif /* CONFIG_SYSFS */
1523 static void mod_sysfs_teardown(struct module *mod)
1525 del_usage_links(mod);
1526 module_remove_modinfo_attrs(mod);
1527 module_param_sysfs_remove(mod);
1528 kobject_put(mod->mkobj.drivers_dir);
1529 kobject_put(mod->holders_dir);
1530 mod_sysfs_fini(mod);
1534 * unlink the module with the whole machine is stopped with interrupts off
1535 * - this defends against kallsyms not taking locks
1537 static int __unlink_module(void *_mod)
1539 struct module *mod = _mod;
1540 list_del(&mod->list);
1541 module_bug_cleanup(mod);
1542 return 0;
1545 /* Free a module, remove from lists, etc. */
1546 static void free_module(struct module *mod)
1548 trace_module_free(mod);
1550 /* Delete from various lists */
1551 mutex_lock(&module_mutex);
1552 stop_machine(__unlink_module, mod, NULL);
1553 mutex_unlock(&module_mutex);
1554 mod_sysfs_teardown(mod);
1556 /* Remove dynamic debug info */
1557 ddebug_remove_module(mod->name);
1559 /* Arch-specific cleanup. */
1560 module_arch_cleanup(mod);
1562 /* Module unload stuff */
1563 module_unload_free(mod);
1565 /* Free any allocated parameters. */
1566 destroy_params(mod->kp, mod->num_kp);
1568 /* This may be NULL, but that's OK */
1569 module_free(mod, mod->module_init);
1570 kfree(mod->args);
1571 percpu_modfree(mod);
1573 /* Free lock-classes: */
1574 lockdep_free_key_range(mod->module_core, mod->core_size);
1576 /* Finally, free the core (containing the module structure) */
1577 module_free(mod, mod->module_core);
1579 #ifdef CONFIG_MPU
1580 update_protections(current->mm);
1581 #endif
1584 void *__symbol_get(const char *symbol)
1586 struct module *owner;
1587 const struct kernel_symbol *sym;
1589 preempt_disable();
1590 sym = find_symbol(symbol, &owner, NULL, true, true);
1591 if (sym && strong_try_module_get(owner))
1592 sym = NULL;
1593 preempt_enable();
1595 return sym ? (void *)sym->value : NULL;
1597 EXPORT_SYMBOL_GPL(__symbol_get);
1600 * Ensure that an exported symbol [global namespace] does not already exist
1601 * in the kernel or in some other module's exported symbol table.
1603 * You must hold the module_mutex.
1605 static int verify_export_symbols(struct module *mod)
1607 unsigned int i;
1608 struct module *owner;
1609 const struct kernel_symbol *s;
1610 struct {
1611 const struct kernel_symbol *sym;
1612 unsigned int num;
1613 } arr[] = {
1614 { mod->syms, mod->num_syms },
1615 { mod->gpl_syms, mod->num_gpl_syms },
1616 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1617 #ifdef CONFIG_UNUSED_SYMBOLS
1618 { mod->unused_syms, mod->num_unused_syms },
1619 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1620 #endif
1623 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1624 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1625 if (find_symbol(s->name, &owner, NULL, true, false)) {
1626 printk(KERN_ERR
1627 "%s: exports duplicate symbol %s"
1628 " (owned by %s)\n",
1629 mod->name, s->name, module_name(owner));
1630 return -ENOEXEC;
1634 return 0;
1637 /* Change all symbols so that st_value encodes the pointer directly. */
1638 static int simplify_symbols(struct module *mod, const struct load_info *info)
1640 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
1641 Elf_Sym *sym = (void *)symsec->sh_addr;
1642 unsigned long secbase;
1643 unsigned int i;
1644 int ret = 0;
1645 const struct kernel_symbol *ksym;
1647 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
1648 const char *name = info->strtab + sym[i].st_name;
1650 switch (sym[i].st_shndx) {
1651 case SHN_COMMON:
1652 /* We compiled with -fno-common. These are not
1653 supposed to happen. */
1654 DEBUGP("Common symbol: %s\n", name);
1655 printk("%s: please compile with -fno-common\n",
1656 mod->name);
1657 ret = -ENOEXEC;
1658 break;
1660 case SHN_ABS:
1661 /* Don't need to do anything */
1662 DEBUGP("Absolute symbol: 0x%08lx\n",
1663 (long)sym[i].st_value);
1664 break;
1666 case SHN_UNDEF:
1667 ksym = resolve_symbol_wait(mod, info, name);
1668 /* Ok if resolved. */
1669 if (ksym && !IS_ERR(ksym)) {
1670 sym[i].st_value = ksym->value;
1671 break;
1674 /* Ok if weak. */
1675 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
1676 break;
1678 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
1679 mod->name, name, PTR_ERR(ksym));
1680 ret = PTR_ERR(ksym) ?: -ENOENT;
1681 break;
1683 default:
1684 /* Divert to percpu allocation if a percpu var. */
1685 if (sym[i].st_shndx == info->index.pcpu)
1686 secbase = (unsigned long)mod_percpu(mod);
1687 else
1688 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
1689 sym[i].st_value += secbase;
1690 break;
1694 return ret;
1697 static int apply_relocations(struct module *mod, const struct load_info *info)
1699 unsigned int i;
1700 int err = 0;
1702 /* Now do relocations. */
1703 for (i = 1; i < info->hdr->e_shnum; i++) {
1704 unsigned int infosec = info->sechdrs[i].sh_info;
1706 /* Not a valid relocation section? */
1707 if (infosec >= info->hdr->e_shnum)
1708 continue;
1710 /* Don't bother with non-allocated sections */
1711 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
1712 continue;
1714 if (info->sechdrs[i].sh_type == SHT_REL)
1715 err = apply_relocate(info->sechdrs, info->strtab,
1716 info->index.sym, i, mod);
1717 else if (info->sechdrs[i].sh_type == SHT_RELA)
1718 err = apply_relocate_add(info->sechdrs, info->strtab,
1719 info->index.sym, i, mod);
1720 if (err < 0)
1721 break;
1723 return err;
1726 /* Additional bytes needed by arch in front of individual sections */
1727 unsigned int __weak arch_mod_section_prepend(struct module *mod,
1728 unsigned int section)
1730 /* default implementation just returns zero */
1731 return 0;
1734 /* Update size with this section: return offset. */
1735 static long get_offset(struct module *mod, unsigned int *size,
1736 Elf_Shdr *sechdr, unsigned int section)
1738 long ret;
1740 *size += arch_mod_section_prepend(mod, section);
1741 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1742 *size = ret + sechdr->sh_size;
1743 return ret;
1746 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1747 might -- code, read-only data, read-write data, small data. Tally
1748 sizes, and place the offsets into sh_entsize fields: high bit means it
1749 belongs in init. */
1750 static void layout_sections(struct module *mod, struct load_info *info)
1752 static unsigned long const masks[][2] = {
1753 /* NOTE: all executable code must be the first section
1754 * in this array; otherwise modify the text_size
1755 * finder in the two loops below */
1756 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1757 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1758 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1759 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1761 unsigned int m, i;
1763 for (i = 0; i < info->hdr->e_shnum; i++)
1764 info->sechdrs[i].sh_entsize = ~0UL;
1766 DEBUGP("Core section allocation order:\n");
1767 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1768 for (i = 0; i < info->hdr->e_shnum; ++i) {
1769 Elf_Shdr *s = &info->sechdrs[i];
1770 const char *sname = info->secstrings + s->sh_name;
1772 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1773 || (s->sh_flags & masks[m][1])
1774 || s->sh_entsize != ~0UL
1775 || strstarts(sname, ".init"))
1776 continue;
1777 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
1778 DEBUGP("\t%s\n", name);
1780 if (m == 0)
1781 mod->core_text_size = mod->core_size;
1784 DEBUGP("Init section allocation order:\n");
1785 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1786 for (i = 0; i < info->hdr->e_shnum; ++i) {
1787 Elf_Shdr *s = &info->sechdrs[i];
1788 const char *sname = info->secstrings + s->sh_name;
1790 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1791 || (s->sh_flags & masks[m][1])
1792 || s->sh_entsize != ~0UL
1793 || !strstarts(sname, ".init"))
1794 continue;
1795 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
1796 | INIT_OFFSET_MASK);
1797 DEBUGP("\t%s\n", sname);
1799 if (m == 0)
1800 mod->init_text_size = mod->init_size;
1804 static void set_license(struct module *mod, const char *license)
1806 if (!license)
1807 license = "unspecified";
1809 if (!license_is_gpl_compatible(license)) {
1810 if (!test_taint(TAINT_PROPRIETARY_MODULE))
1811 printk(KERN_WARNING "%s: module license '%s' taints "
1812 "kernel.\n", mod->name, license);
1813 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1817 /* Parse tag=value strings from .modinfo section */
1818 static char *next_string(char *string, unsigned long *secsize)
1820 /* Skip non-zero chars */
1821 while (string[0]) {
1822 string++;
1823 if ((*secsize)-- <= 1)
1824 return NULL;
1827 /* Skip any zero padding. */
1828 while (!string[0]) {
1829 string++;
1830 if ((*secsize)-- <= 1)
1831 return NULL;
1833 return string;
1836 static char *get_modinfo(struct load_info *info, const char *tag)
1838 char *p;
1839 unsigned int taglen = strlen(tag);
1840 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
1841 unsigned long size = infosec->sh_size;
1843 for (p = (char *)infosec->sh_addr; p; p = next_string(p, &size)) {
1844 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1845 return p + taglen + 1;
1847 return NULL;
1850 static void setup_modinfo(struct module *mod, struct load_info *info)
1852 struct module_attribute *attr;
1853 int i;
1855 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1856 if (attr->setup)
1857 attr->setup(mod, get_modinfo(info, attr->attr.name));
1861 static void free_modinfo(struct module *mod)
1863 struct module_attribute *attr;
1864 int i;
1866 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1867 if (attr->free)
1868 attr->free(mod);
1872 #ifdef CONFIG_KALLSYMS
1874 /* lookup symbol in given range of kernel_symbols */
1875 static const struct kernel_symbol *lookup_symbol(const char *name,
1876 const struct kernel_symbol *start,
1877 const struct kernel_symbol *stop)
1879 const struct kernel_symbol *ks = start;
1880 for (; ks < stop; ks++)
1881 if (strcmp(ks->name, name) == 0)
1882 return ks;
1883 return NULL;
1886 static int is_exported(const char *name, unsigned long value,
1887 const struct module *mod)
1889 const struct kernel_symbol *ks;
1890 if (!mod)
1891 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1892 else
1893 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1894 return ks != NULL && ks->value == value;
1897 /* As per nm */
1898 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
1900 const Elf_Shdr *sechdrs = info->sechdrs;
1902 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1903 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1904 return 'v';
1905 else
1906 return 'w';
1908 if (sym->st_shndx == SHN_UNDEF)
1909 return 'U';
1910 if (sym->st_shndx == SHN_ABS)
1911 return 'a';
1912 if (sym->st_shndx >= SHN_LORESERVE)
1913 return '?';
1914 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1915 return 't';
1916 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1917 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1918 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1919 return 'r';
1920 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1921 return 'g';
1922 else
1923 return 'd';
1925 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1926 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1927 return 's';
1928 else
1929 return 'b';
1931 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
1932 ".debug")) {
1933 return 'n';
1935 return '?';
1938 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1939 unsigned int shnum)
1941 const Elf_Shdr *sec;
1943 if (src->st_shndx == SHN_UNDEF
1944 || src->st_shndx >= shnum
1945 || !src->st_name)
1946 return false;
1948 sec = sechdrs + src->st_shndx;
1949 if (!(sec->sh_flags & SHF_ALLOC)
1950 #ifndef CONFIG_KALLSYMS_ALL
1951 || !(sec->sh_flags & SHF_EXECINSTR)
1952 #endif
1953 || (sec->sh_entsize & INIT_OFFSET_MASK))
1954 return false;
1956 return true;
1959 static void layout_symtab(struct module *mod, struct load_info *info)
1961 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
1962 Elf_Shdr *strsect = info->sechdrs + info->index.str;
1963 const Elf_Sym *src;
1964 unsigned int i, nsrc, ndst;
1966 /* Put symbol section at end of init part of module. */
1967 symsect->sh_flags |= SHF_ALLOC;
1968 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1969 info->index.sym) | INIT_OFFSET_MASK;
1970 DEBUGP("\t%s\n", info->secstrings + symsect->sh_name);
1972 src = (void *)info->hdr + symsect->sh_offset;
1973 nsrc = symsect->sh_size / sizeof(*src);
1974 for (ndst = i = 1; i < nsrc; ++i, ++src)
1975 if (is_core_symbol(src, info->sechdrs, info->hdr->e_shnum)) {
1976 unsigned int j = src->st_name;
1978 while (!__test_and_set_bit(j, info->strmap)
1979 && info->strtab[j])
1980 ++j;
1981 ++ndst;
1984 /* Append room for core symbols at end of core part. */
1985 info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
1986 mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym);
1988 /* Put string table section at end of init part of module. */
1989 strsect->sh_flags |= SHF_ALLOC;
1990 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
1991 info->index.str) | INIT_OFFSET_MASK;
1992 DEBUGP("\t%s\n", info->secstrings + strsect->sh_name);
1994 /* Append room for core symbols' strings at end of core part. */
1995 info->stroffs = mod->core_size;
1996 __set_bit(0, info->strmap);
1997 mod->core_size += bitmap_weight(info->strmap, strsect->sh_size);
2000 static void add_kallsyms(struct module *mod, const struct load_info *info)
2002 unsigned int i, ndst;
2003 const Elf_Sym *src;
2004 Elf_Sym *dst;
2005 char *s;
2006 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2008 mod->symtab = (void *)symsec->sh_addr;
2009 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
2010 /* Make sure we get permanent strtab: don't use info->strtab. */
2011 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
2013 /* Set types up while we still have access to sections. */
2014 for (i = 0; i < mod->num_symtab; i++)
2015 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
2017 mod->core_symtab = dst = mod->module_core + info->symoffs;
2018 src = mod->symtab;
2019 *dst = *src;
2020 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
2021 if (!is_core_symbol(src, info->sechdrs, info->hdr->e_shnum))
2022 continue;
2023 dst[ndst] = *src;
2024 dst[ndst].st_name = bitmap_weight(info->strmap,
2025 dst[ndst].st_name);
2026 ++ndst;
2028 mod->core_num_syms = ndst;
2030 mod->core_strtab = s = mod->module_core + info->stroffs;
2031 for (*s = 0, i = 1; i < info->sechdrs[info->index.str].sh_size; ++i)
2032 if (test_bit(i, info->strmap))
2033 *++s = mod->strtab[i];
2035 #else
2036 static inline void layout_symtab(struct module *mod, struct load_info *info)
2040 static void add_kallsyms(struct module *mod, const struct load_info *info)
2043 #endif /* CONFIG_KALLSYMS */
2045 static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2047 if (!debug)
2048 return;
2049 #ifdef CONFIG_DYNAMIC_DEBUG
2050 if (ddebug_add_module(debug, num, debug->modname))
2051 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2052 debug->modname);
2053 #endif
2056 static void dynamic_debug_remove(struct _ddebug *debug)
2058 if (debug)
2059 ddebug_remove_module(debug->modname);
2062 static void *module_alloc_update_bounds(unsigned long size)
2064 void *ret = module_alloc(size);
2066 if (ret) {
2067 mutex_lock(&module_mutex);
2068 /* Update module bounds. */
2069 if ((unsigned long)ret < module_addr_min)
2070 module_addr_min = (unsigned long)ret;
2071 if ((unsigned long)ret + size > module_addr_max)
2072 module_addr_max = (unsigned long)ret + size;
2073 mutex_unlock(&module_mutex);
2075 return ret;
2078 #ifdef CONFIG_DEBUG_KMEMLEAK
2079 static void kmemleak_load_module(const struct module *mod,
2080 const struct load_info *info)
2082 unsigned int i;
2084 /* only scan the sections containing data */
2085 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
2087 for (i = 1; i < info->hdr->e_shnum; i++) {
2088 const char *name = info->secstrings + info->sechdrs[i].sh_name;
2089 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC))
2090 continue;
2091 if (!strstarts(name, ".data") && !strstarts(name, ".bss"))
2092 continue;
2094 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2095 info->sechdrs[i].sh_size, GFP_KERNEL);
2098 #else
2099 static inline void kmemleak_load_module(const struct module *mod,
2100 const struct load_info *info)
2103 #endif
2105 /* Sets info->hdr and info->len. */
2106 static int copy_and_check(struct load_info *info,
2107 const void __user *umod, unsigned long len,
2108 const char __user *uargs)
2110 int err;
2111 Elf_Ehdr *hdr;
2113 if (len < sizeof(*hdr))
2114 return -ENOEXEC;
2116 /* Suck in entire file: we'll want most of it. */
2117 /* vmalloc barfs on "unusual" numbers. Check here */
2118 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
2119 return -ENOMEM;
2121 if (copy_from_user(hdr, umod, len) != 0) {
2122 err = -EFAULT;
2123 goto free_hdr;
2126 /* Sanity checks against insmoding binaries or wrong arch,
2127 weird elf version */
2128 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
2129 || hdr->e_type != ET_REL
2130 || !elf_check_arch(hdr)
2131 || hdr->e_shentsize != sizeof(Elf_Shdr)) {
2132 err = -ENOEXEC;
2133 goto free_hdr;
2136 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
2137 err = -ENOEXEC;
2138 goto free_hdr;
2141 info->hdr = hdr;
2142 info->len = len;
2143 return 0;
2145 free_hdr:
2146 vfree(hdr);
2147 return err;
2150 static void free_copy(struct load_info *info)
2152 vfree(info->hdr);
2155 static int rewrite_section_headers(struct load_info *info)
2157 unsigned int i;
2159 /* This should always be true, but let's be sure. */
2160 info->sechdrs[0].sh_addr = 0;
2162 for (i = 1; i < info->hdr->e_shnum; i++) {
2163 Elf_Shdr *shdr = &info->sechdrs[i];
2164 if (shdr->sh_type != SHT_NOBITS
2165 && info->len < shdr->sh_offset + shdr->sh_size) {
2166 printk(KERN_ERR "Module len %lu truncated\n",
2167 info->len);
2168 return -ENOEXEC;
2171 /* Mark all sections sh_addr with their address in the
2172 temporary image. */
2173 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2175 #ifndef CONFIG_MODULE_UNLOAD
2176 /* Don't load .exit sections */
2177 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2178 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2179 #endif
2182 /* Track but don't keep modinfo and version sections. */
2183 info->index.vers = find_sec(info, "__versions");
2184 info->index.info = find_sec(info, ".modinfo");
2185 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2186 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2187 return 0;
2191 * Set up our basic convenience variables (pointers to section headers,
2192 * search for module section index etc), and do some basic section
2193 * verification.
2195 * Return the temporary module pointer (we'll replace it with the final
2196 * one when we move the module sections around).
2198 static struct module *setup_load_info(struct load_info *info)
2200 unsigned int i;
2201 int err;
2202 struct module *mod;
2204 /* Set up the convenience variables */
2205 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2206 info->secstrings = (void *)info->hdr
2207 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
2209 err = rewrite_section_headers(info);
2210 if (err)
2211 return ERR_PTR(err);
2213 /* Find internal symbols and strings. */
2214 for (i = 1; i < info->hdr->e_shnum; i++) {
2215 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2216 info->index.sym = i;
2217 info->index.str = info->sechdrs[i].sh_link;
2218 info->strtab = (char *)info->hdr
2219 + info->sechdrs[info->index.str].sh_offset;
2220 break;
2224 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
2225 if (!info->index.mod) {
2226 printk(KERN_WARNING "No module found in object\n");
2227 return ERR_PTR(-ENOEXEC);
2229 /* This is temporary: point mod into copy of data. */
2230 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2232 if (info->index.sym == 0) {
2233 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2234 mod->name);
2235 return ERR_PTR(-ENOEXEC);
2238 info->index.pcpu = find_pcpusec(info);
2240 /* Check module struct version now, before we try to use module. */
2241 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2242 return ERR_PTR(-ENOEXEC);
2244 return mod;
2247 static int check_modinfo(struct module *mod, struct load_info *info)
2249 const char *modmagic = get_modinfo(info, "vermagic");
2250 int err;
2252 /* This is allowed: modprobe --force will invalidate it. */
2253 if (!modmagic) {
2254 err = try_to_force_load(mod, "bad vermagic");
2255 if (err)
2256 return err;
2257 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2258 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2259 mod->name, modmagic, vermagic);
2260 return -ENOEXEC;
2263 if (get_modinfo(info, "staging")) {
2264 add_taint_module(mod, TAINT_CRAP);
2265 printk(KERN_WARNING "%s: module is from the staging directory,"
2266 " the quality is unknown, you have been warned.\n",
2267 mod->name);
2270 /* Set up license info based on the info section */
2271 set_license(mod, get_modinfo(info, "license"));
2273 return 0;
2276 static void find_module_sections(struct module *mod, struct load_info *info)
2278 mod->kp = section_objs(info, "__param",
2279 sizeof(*mod->kp), &mod->num_kp);
2280 mod->syms = section_objs(info, "__ksymtab",
2281 sizeof(*mod->syms), &mod->num_syms);
2282 mod->crcs = section_addr(info, "__kcrctab");
2283 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2284 sizeof(*mod->gpl_syms),
2285 &mod->num_gpl_syms);
2286 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2287 mod->gpl_future_syms = section_objs(info,
2288 "__ksymtab_gpl_future",
2289 sizeof(*mod->gpl_future_syms),
2290 &mod->num_gpl_future_syms);
2291 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
2293 #ifdef CONFIG_UNUSED_SYMBOLS
2294 mod->unused_syms = section_objs(info, "__ksymtab_unused",
2295 sizeof(*mod->unused_syms),
2296 &mod->num_unused_syms);
2297 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
2298 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
2299 sizeof(*mod->unused_gpl_syms),
2300 &mod->num_unused_gpl_syms);
2301 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
2302 #endif
2303 #ifdef CONFIG_CONSTRUCTORS
2304 mod->ctors = section_objs(info, ".ctors",
2305 sizeof(*mod->ctors), &mod->num_ctors);
2306 #endif
2308 #ifdef CONFIG_TRACEPOINTS
2309 mod->tracepoints = section_objs(info, "__tracepoints",
2310 sizeof(*mod->tracepoints),
2311 &mod->num_tracepoints);
2312 #endif
2313 #ifdef HAVE_JUMP_LABEL
2314 mod->jump_entries = section_objs(info, "__jump_table",
2315 sizeof(*mod->jump_entries),
2316 &mod->num_jump_entries);
2317 #endif
2318 #ifdef CONFIG_EVENT_TRACING
2319 mod->trace_events = section_objs(info, "_ftrace_events",
2320 sizeof(*mod->trace_events),
2321 &mod->num_trace_events);
2323 * This section contains pointers to allocated objects in the trace
2324 * code and not scanning it leads to false positives.
2326 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2327 mod->num_trace_events, GFP_KERNEL);
2328 #endif
2329 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
2330 /* sechdrs[0].sh_size is always zero */
2331 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
2332 sizeof(*mod->ftrace_callsites),
2333 &mod->num_ftrace_callsites);
2334 #endif
2336 mod->extable = section_objs(info, "__ex_table",
2337 sizeof(*mod->extable), &mod->num_exentries);
2339 if (section_addr(info, "__obsparm"))
2340 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2341 mod->name);
2343 info->debug = section_objs(info, "__verbose",
2344 sizeof(*info->debug), &info->num_debug);
2347 static int move_module(struct module *mod, struct load_info *info)
2349 int i;
2350 void *ptr;
2352 /* Do the allocs. */
2353 ptr = module_alloc_update_bounds(mod->core_size);
2355 * The pointer to this block is stored in the module structure
2356 * which is inside the block. Just mark it as not being a
2357 * leak.
2359 kmemleak_not_leak(ptr);
2360 if (!ptr)
2361 return -ENOMEM;
2363 memset(ptr, 0, mod->core_size);
2364 mod->module_core = ptr;
2366 ptr = module_alloc_update_bounds(mod->init_size);
2368 * The pointer to this block is stored in the module structure
2369 * which is inside the block. This block doesn't need to be
2370 * scanned as it contains data and code that will be freed
2371 * after the module is initialized.
2373 kmemleak_ignore(ptr);
2374 if (!ptr && mod->init_size) {
2375 module_free(mod, mod->module_core);
2376 return -ENOMEM;
2378 memset(ptr, 0, mod->init_size);
2379 mod->module_init = ptr;
2381 /* Transfer each section which specifies SHF_ALLOC */
2382 DEBUGP("final section addresses:\n");
2383 for (i = 0; i < info->hdr->e_shnum; i++) {
2384 void *dest;
2385 Elf_Shdr *shdr = &info->sechdrs[i];
2387 if (!(shdr->sh_flags & SHF_ALLOC))
2388 continue;
2390 if (shdr->sh_entsize & INIT_OFFSET_MASK)
2391 dest = mod->module_init
2392 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
2393 else
2394 dest = mod->module_core + shdr->sh_entsize;
2396 if (shdr->sh_type != SHT_NOBITS)
2397 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2398 /* Update sh_addr to point to copy in image. */
2399 shdr->sh_addr = (unsigned long)dest;
2400 DEBUGP("\t0x%lx %s\n",
2401 shdr->sh_addr, info->secstrings + shdr->sh_name);
2404 return 0;
2407 static int check_module_license_and_versions(struct module *mod)
2410 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2411 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2412 * using GPL-only symbols it needs.
2414 if (strcmp(mod->name, "ndiswrapper") == 0)
2415 add_taint(TAINT_PROPRIETARY_MODULE);
2417 /* driverloader was caught wrongly pretending to be under GPL */
2418 if (strcmp(mod->name, "driverloader") == 0)
2419 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2421 #ifdef CONFIG_MODVERSIONS
2422 if ((mod->num_syms && !mod->crcs)
2423 || (mod->num_gpl_syms && !mod->gpl_crcs)
2424 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2425 #ifdef CONFIG_UNUSED_SYMBOLS
2426 || (mod->num_unused_syms && !mod->unused_crcs)
2427 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2428 #endif
2430 return try_to_force_load(mod,
2431 "no versions for exported symbols");
2433 #endif
2434 return 0;
2437 static void flush_module_icache(const struct module *mod)
2439 mm_segment_t old_fs;
2441 /* flush the icache in correct context */
2442 old_fs = get_fs();
2443 set_fs(KERNEL_DS);
2446 * Flush the instruction cache, since we've played with text.
2447 * Do it before processing of module parameters, so the module
2448 * can provide parameter accessor functions of its own.
2450 if (mod->module_init)
2451 flush_icache_range((unsigned long)mod->module_init,
2452 (unsigned long)mod->module_init
2453 + mod->init_size);
2454 flush_icache_range((unsigned long)mod->module_core,
2455 (unsigned long)mod->module_core + mod->core_size);
2457 set_fs(old_fs);
2460 static struct module *layout_and_allocate(struct load_info *info)
2462 /* Module within temporary copy. */
2463 struct module *mod;
2464 Elf_Shdr *pcpusec;
2465 int err;
2467 mod = setup_load_info(info);
2468 if (IS_ERR(mod))
2469 return mod;
2471 err = check_modinfo(mod, info);
2472 if (err)
2473 return ERR_PTR(err);
2475 /* Allow arches to frob section contents and sizes. */
2476 err = module_frob_arch_sections(info->hdr, info->sechdrs,
2477 info->secstrings, mod);
2478 if (err < 0)
2479 goto out;
2481 pcpusec = &info->sechdrs[info->index.pcpu];
2482 if (pcpusec->sh_size) {
2483 /* We have a special allocation for this section. */
2484 err = percpu_modalloc(mod,
2485 pcpusec->sh_size, pcpusec->sh_addralign);
2486 if (err)
2487 goto out;
2488 pcpusec->sh_flags &= ~(unsigned long)SHF_ALLOC;
2491 /* Determine total sizes, and put offsets in sh_entsize. For now
2492 this is done generically; there doesn't appear to be any
2493 special cases for the architectures. */
2494 layout_sections(mod, info);
2496 info->strmap = kzalloc(BITS_TO_LONGS(info->sechdrs[info->index.str].sh_size)
2497 * sizeof(long), GFP_KERNEL);
2498 if (!info->strmap) {
2499 err = -ENOMEM;
2500 goto free_percpu;
2502 layout_symtab(mod, info);
2504 /* Allocate and move to the final place */
2505 err = move_module(mod, info);
2506 if (err)
2507 goto free_strmap;
2509 /* Module has been copied to its final place now: return it. */
2510 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2511 kmemleak_load_module(mod, info);
2512 return mod;
2514 free_strmap:
2515 kfree(info->strmap);
2516 free_percpu:
2517 percpu_modfree(mod);
2518 out:
2519 return ERR_PTR(err);
2522 /* mod is no longer valid after this! */
2523 static void module_deallocate(struct module *mod, struct load_info *info)
2525 kfree(info->strmap);
2526 percpu_modfree(mod);
2527 module_free(mod, mod->module_init);
2528 module_free(mod, mod->module_core);
2531 static int post_relocation(struct module *mod, const struct load_info *info)
2533 /* Sort exception table now relocations are done. */
2534 sort_extable(mod->extable, mod->extable + mod->num_exentries);
2536 /* Copy relocated percpu area over. */
2537 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
2538 info->sechdrs[info->index.pcpu].sh_size);
2540 /* Setup kallsyms-specific fields. */
2541 add_kallsyms(mod, info);
2543 /* Arch-specific module finalizing. */
2544 return module_finalize(info->hdr, info->sechdrs, mod);
2547 /* Allocate and load the module: note that size of section 0 is always
2548 zero, and we rely on this for optional sections. */
2549 static struct module *load_module(void __user *umod,
2550 unsigned long len,
2551 const char __user *uargs)
2553 struct load_info info = { NULL, };
2554 struct module *mod;
2555 long err;
2557 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2558 umod, len, uargs);
2560 /* Copy in the blobs from userspace, check they are vaguely sane. */
2561 err = copy_and_check(&info, umod, len, uargs);
2562 if (err)
2563 return ERR_PTR(err);
2565 /* Figure out module layout, and allocate all the memory. */
2566 mod = layout_and_allocate(&info);
2567 if (IS_ERR(mod)) {
2568 err = PTR_ERR(mod);
2569 goto free_copy;
2572 /* Now module is in final location, initialize linked lists, etc. */
2573 err = module_unload_init(mod);
2574 if (err)
2575 goto free_module;
2577 /* Now we've got everything in the final locations, we can
2578 * find optional sections. */
2579 find_module_sections(mod, &info);
2581 err = check_module_license_and_versions(mod);
2582 if (err)
2583 goto free_unload;
2585 /* Set up MODINFO_ATTR fields */
2586 setup_modinfo(mod, &info);
2588 /* Fix up syms, so that st_value is a pointer to location. */
2589 err = simplify_symbols(mod, &info);
2590 if (err < 0)
2591 goto free_modinfo;
2593 err = apply_relocations(mod, &info);
2594 if (err < 0)
2595 goto free_modinfo;
2597 err = post_relocation(mod, &info);
2598 if (err < 0)
2599 goto free_modinfo;
2601 flush_module_icache(mod);
2603 /* Now copy in args */
2604 mod->args = strndup_user(uargs, ~0UL >> 1);
2605 if (IS_ERR(mod->args)) {
2606 err = PTR_ERR(mod->args);
2607 goto free_arch_cleanup;
2610 /* Mark state as coming so strong_try_module_get() ignores us. */
2611 mod->state = MODULE_STATE_COMING;
2613 /* Now sew it into the lists so we can get lockdep and oops
2614 * info during argument parsing. Noone should access us, since
2615 * strong_try_module_get() will fail.
2616 * lockdep/oops can run asynchronous, so use the RCU list insertion
2617 * function to insert in a way safe to concurrent readers.
2618 * The mutex protects against concurrent writers.
2620 mutex_lock(&module_mutex);
2621 if (find_module(mod->name)) {
2622 err = -EEXIST;
2623 goto unlock;
2626 /* This has to be done once we're sure module name is unique. */
2627 if (!mod->taints)
2628 dynamic_debug_setup(info.debug, info.num_debug);
2630 /* Find duplicate symbols */
2631 err = verify_export_symbols(mod);
2632 if (err < 0)
2633 goto ddebug;
2635 module_bug_finalize(info.hdr, info.sechdrs, mod);
2636 list_add_rcu(&mod->list, &modules);
2637 mutex_unlock(&module_mutex);
2639 /* Module is ready to execute: parsing args may do that. */
2640 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
2641 if (err < 0)
2642 goto unlink;
2644 /* Link in to syfs. */
2645 err = mod_sysfs_setup(mod, &info, mod->kp, mod->num_kp);
2646 if (err < 0)
2647 goto unlink;
2649 /* Get rid of temporary copy and strmap. */
2650 kfree(info.strmap);
2651 free_copy(&info);
2653 /* Done! */
2654 trace_module_load(mod);
2655 return mod;
2657 unlink:
2658 mutex_lock(&module_mutex);
2659 /* Unlink carefully: kallsyms could be walking list. */
2660 list_del_rcu(&mod->list);
2661 module_bug_cleanup(mod);
2663 ddebug:
2664 if (!mod->taints)
2665 dynamic_debug_remove(info.debug);
2666 unlock:
2667 mutex_unlock(&module_mutex);
2668 synchronize_sched();
2669 kfree(mod->args);
2670 free_arch_cleanup:
2671 module_arch_cleanup(mod);
2672 free_modinfo:
2673 free_modinfo(mod);
2674 free_unload:
2675 module_unload_free(mod);
2676 free_module:
2677 module_deallocate(mod, &info);
2678 free_copy:
2679 free_copy(&info);
2680 return ERR_PTR(err);
2683 /* Call module constructors. */
2684 static void do_mod_ctors(struct module *mod)
2686 #ifdef CONFIG_CONSTRUCTORS
2687 unsigned long i;
2689 for (i = 0; i < mod->num_ctors; i++)
2690 mod->ctors[i]();
2691 #endif
2694 /* This is where the real work happens */
2695 SYSCALL_DEFINE3(init_module, void __user *, umod,
2696 unsigned long, len, const char __user *, uargs)
2698 struct module *mod;
2699 int ret = 0;
2701 /* Must have permission */
2702 if (!capable(CAP_SYS_MODULE) || modules_disabled)
2703 return -EPERM;
2705 /* Do all the hard work */
2706 mod = load_module(umod, len, uargs);
2707 if (IS_ERR(mod))
2708 return PTR_ERR(mod);
2710 blocking_notifier_call_chain(&module_notify_list,
2711 MODULE_STATE_COMING, mod);
2713 do_mod_ctors(mod);
2714 /* Start the module */
2715 if (mod->init != NULL)
2716 ret = do_one_initcall(mod->init);
2717 if (ret < 0) {
2718 /* Init routine failed: abort. Try to protect us from
2719 buggy refcounters. */
2720 mod->state = MODULE_STATE_GOING;
2721 synchronize_sched();
2722 module_put(mod);
2723 blocking_notifier_call_chain(&module_notify_list,
2724 MODULE_STATE_GOING, mod);
2725 free_module(mod);
2726 wake_up(&module_wq);
2727 return ret;
2729 if (ret > 0) {
2730 printk(KERN_WARNING
2731 "%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2732 "%s: loading module anyway...\n",
2733 __func__, mod->name, ret,
2734 __func__);
2735 dump_stack();
2738 /* Now it's a first class citizen! Wake up anyone waiting for it. */
2739 mod->state = MODULE_STATE_LIVE;
2740 wake_up(&module_wq);
2741 blocking_notifier_call_chain(&module_notify_list,
2742 MODULE_STATE_LIVE, mod);
2744 /* We need to finish all async code before the module init sequence is done */
2745 async_synchronize_full();
2747 mutex_lock(&module_mutex);
2748 /* Drop initial reference. */
2749 module_put(mod);
2750 trim_init_extable(mod);
2751 #ifdef CONFIG_KALLSYMS
2752 mod->num_symtab = mod->core_num_syms;
2753 mod->symtab = mod->core_symtab;
2754 mod->strtab = mod->core_strtab;
2755 #endif
2756 module_free(mod, mod->module_init);
2757 mod->module_init = NULL;
2758 mod->init_size = 0;
2759 mod->init_text_size = 0;
2760 mutex_unlock(&module_mutex);
2762 return 0;
2765 static inline int within(unsigned long addr, void *start, unsigned long size)
2767 return ((void *)addr >= start && (void *)addr < start + size);
2770 #ifdef CONFIG_KALLSYMS
2772 * This ignores the intensely annoying "mapping symbols" found
2773 * in ARM ELF files: $a, $t and $d.
2775 static inline int is_arm_mapping_symbol(const char *str)
2777 return str[0] == '$' && strchr("atd", str[1])
2778 && (str[2] == '\0' || str[2] == '.');
2781 static const char *get_ksymbol(struct module *mod,
2782 unsigned long addr,
2783 unsigned long *size,
2784 unsigned long *offset)
2786 unsigned int i, best = 0;
2787 unsigned long nextval;
2789 /* At worse, next value is at end of module */
2790 if (within_module_init(addr, mod))
2791 nextval = (unsigned long)mod->module_init+mod->init_text_size;
2792 else
2793 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2795 /* Scan for closest preceeding symbol, and next symbol. (ELF
2796 starts real symbols at 1). */
2797 for (i = 1; i < mod->num_symtab; i++) {
2798 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2799 continue;
2801 /* We ignore unnamed symbols: they're uninformative
2802 * and inserted at a whim. */
2803 if (mod->symtab[i].st_value <= addr
2804 && mod->symtab[i].st_value > mod->symtab[best].st_value
2805 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2806 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2807 best = i;
2808 if (mod->symtab[i].st_value > addr
2809 && mod->symtab[i].st_value < nextval
2810 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2811 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2812 nextval = mod->symtab[i].st_value;
2815 if (!best)
2816 return NULL;
2818 if (size)
2819 *size = nextval - mod->symtab[best].st_value;
2820 if (offset)
2821 *offset = addr - mod->symtab[best].st_value;
2822 return mod->strtab + mod->symtab[best].st_name;
2825 /* For kallsyms to ask for address resolution. NULL means not found. Careful
2826 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2827 const char *module_address_lookup(unsigned long addr,
2828 unsigned long *size,
2829 unsigned long *offset,
2830 char **modname,
2831 char *namebuf)
2833 struct module *mod;
2834 const char *ret = NULL;
2836 preempt_disable();
2837 list_for_each_entry_rcu(mod, &modules, list) {
2838 if (within_module_init(addr, mod) ||
2839 within_module_core(addr, mod)) {
2840 if (modname)
2841 *modname = mod->name;
2842 ret = get_ksymbol(mod, addr, size, offset);
2843 break;
2846 /* Make a copy in here where it's safe */
2847 if (ret) {
2848 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2849 ret = namebuf;
2851 preempt_enable();
2852 return ret;
2855 int lookup_module_symbol_name(unsigned long addr, char *symname)
2857 struct module *mod;
2859 preempt_disable();
2860 list_for_each_entry_rcu(mod, &modules, list) {
2861 if (within_module_init(addr, mod) ||
2862 within_module_core(addr, mod)) {
2863 const char *sym;
2865 sym = get_ksymbol(mod, addr, NULL, NULL);
2866 if (!sym)
2867 goto out;
2868 strlcpy(symname, sym, KSYM_NAME_LEN);
2869 preempt_enable();
2870 return 0;
2873 out:
2874 preempt_enable();
2875 return -ERANGE;
2878 int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2879 unsigned long *offset, char *modname, char *name)
2881 struct module *mod;
2883 preempt_disable();
2884 list_for_each_entry_rcu(mod, &modules, list) {
2885 if (within_module_init(addr, mod) ||
2886 within_module_core(addr, mod)) {
2887 const char *sym;
2889 sym = get_ksymbol(mod, addr, size, offset);
2890 if (!sym)
2891 goto out;
2892 if (modname)
2893 strlcpy(modname, mod->name, MODULE_NAME_LEN);
2894 if (name)
2895 strlcpy(name, sym, KSYM_NAME_LEN);
2896 preempt_enable();
2897 return 0;
2900 out:
2901 preempt_enable();
2902 return -ERANGE;
2905 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2906 char *name, char *module_name, int *exported)
2908 struct module *mod;
2910 preempt_disable();
2911 list_for_each_entry_rcu(mod, &modules, list) {
2912 if (symnum < mod->num_symtab) {
2913 *value = mod->symtab[symnum].st_value;
2914 *type = mod->symtab[symnum].st_info;
2915 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2916 KSYM_NAME_LEN);
2917 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2918 *exported = is_exported(name, *value, mod);
2919 preempt_enable();
2920 return 0;
2922 symnum -= mod->num_symtab;
2924 preempt_enable();
2925 return -ERANGE;
2928 static unsigned long mod_find_symname(struct module *mod, const char *name)
2930 unsigned int i;
2932 for (i = 0; i < mod->num_symtab; i++)
2933 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2934 mod->symtab[i].st_info != 'U')
2935 return mod->symtab[i].st_value;
2936 return 0;
2939 /* Look for this name: can be of form module:name. */
2940 unsigned long module_kallsyms_lookup_name(const char *name)
2942 struct module *mod;
2943 char *colon;
2944 unsigned long ret = 0;
2946 /* Don't lock: we're in enough trouble already. */
2947 preempt_disable();
2948 if ((colon = strchr(name, ':')) != NULL) {
2949 *colon = '\0';
2950 if ((mod = find_module(name)) != NULL)
2951 ret = mod_find_symname(mod, colon+1);
2952 *colon = ':';
2953 } else {
2954 list_for_each_entry_rcu(mod, &modules, list)
2955 if ((ret = mod_find_symname(mod, name)) != 0)
2956 break;
2958 preempt_enable();
2959 return ret;
2962 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
2963 struct module *, unsigned long),
2964 void *data)
2966 struct module *mod;
2967 unsigned int i;
2968 int ret;
2970 list_for_each_entry(mod, &modules, list) {
2971 for (i = 0; i < mod->num_symtab; i++) {
2972 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
2973 mod, mod->symtab[i].st_value);
2974 if (ret != 0)
2975 return ret;
2978 return 0;
2980 #endif /* CONFIG_KALLSYMS */
2982 static char *module_flags(struct module *mod, char *buf)
2984 int bx = 0;
2986 if (mod->taints ||
2987 mod->state == MODULE_STATE_GOING ||
2988 mod->state == MODULE_STATE_COMING) {
2989 buf[bx++] = '(';
2990 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
2991 buf[bx++] = 'P';
2992 if (mod->taints & (1 << TAINT_FORCED_MODULE))
2993 buf[bx++] = 'F';
2994 if (mod->taints & (1 << TAINT_CRAP))
2995 buf[bx++] = 'C';
2997 * TAINT_FORCED_RMMOD: could be added.
2998 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
2999 * apply to modules.
3002 /* Show a - for module-is-being-unloaded */
3003 if (mod->state == MODULE_STATE_GOING)
3004 buf[bx++] = '-';
3005 /* Show a + for module-is-being-loaded */
3006 if (mod->state == MODULE_STATE_COMING)
3007 buf[bx++] = '+';
3008 buf[bx++] = ')';
3010 buf[bx] = '\0';
3012 return buf;
3015 #ifdef CONFIG_PROC_FS
3016 /* Called by the /proc file system to return a list of modules. */
3017 static void *m_start(struct seq_file *m, loff_t *pos)
3019 mutex_lock(&module_mutex);
3020 return seq_list_start(&modules, *pos);
3023 static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3025 return seq_list_next(p, &modules, pos);
3028 static void m_stop(struct seq_file *m, void *p)
3030 mutex_unlock(&module_mutex);
3033 static int m_show(struct seq_file *m, void *p)
3035 struct module *mod = list_entry(p, struct module, list);
3036 char buf[8];
3038 seq_printf(m, "%s %u",
3039 mod->name, mod->init_size + mod->core_size);
3040 print_unload_info(m, mod);
3042 /* Informative for users. */
3043 seq_printf(m, " %s",
3044 mod->state == MODULE_STATE_GOING ? "Unloading":
3045 mod->state == MODULE_STATE_COMING ? "Loading":
3046 "Live");
3047 /* Used by oprofile and other similar tools. */
3048 seq_printf(m, " 0x%p", mod->module_core);
3050 /* Taints info */
3051 if (mod->taints)
3052 seq_printf(m, " %s", module_flags(mod, buf));
3054 seq_printf(m, "\n");
3055 return 0;
3058 /* Format: modulename size refcount deps address
3060 Where refcount is a number or -, and deps is a comma-separated list
3061 of depends or -.
3063 static const struct seq_operations modules_op = {
3064 .start = m_start,
3065 .next = m_next,
3066 .stop = m_stop,
3067 .show = m_show
3070 static int modules_open(struct inode *inode, struct file *file)
3072 return seq_open(file, &modules_op);
3075 static const struct file_operations proc_modules_operations = {
3076 .open = modules_open,
3077 .read = seq_read,
3078 .llseek = seq_lseek,
3079 .release = seq_release,
3082 static int __init proc_modules_init(void)
3084 proc_create("modules", 0, NULL, &proc_modules_operations);
3085 return 0;
3087 module_init(proc_modules_init);
3088 #endif
3090 /* Given an address, look for it in the module exception tables. */
3091 const struct exception_table_entry *search_module_extables(unsigned long addr)
3093 const struct exception_table_entry *e = NULL;
3094 struct module *mod;
3096 preempt_disable();
3097 list_for_each_entry_rcu(mod, &modules, list) {
3098 if (mod->num_exentries == 0)
3099 continue;
3101 e = search_extable(mod->extable,
3102 mod->extable + mod->num_exentries - 1,
3103 addr);
3104 if (e)
3105 break;
3107 preempt_enable();
3109 /* Now, if we found one, we are running inside it now, hence
3110 we cannot unload the module, hence no refcnt needed. */
3111 return e;
3115 * is_module_address - is this address inside a module?
3116 * @addr: the address to check.
3118 * See is_module_text_address() if you simply want to see if the address
3119 * is code (not data).
3121 bool is_module_address(unsigned long addr)
3123 bool ret;
3125 preempt_disable();
3126 ret = __module_address(addr) != NULL;
3127 preempt_enable();
3129 return ret;
3133 * __module_address - get the module which contains an address.
3134 * @addr: the address.
3136 * Must be called with preempt disabled or module mutex held so that
3137 * module doesn't get freed during this.
3139 struct module *__module_address(unsigned long addr)
3141 struct module *mod;
3143 if (addr < module_addr_min || addr > module_addr_max)
3144 return NULL;
3146 list_for_each_entry_rcu(mod, &modules, list)
3147 if (within_module_core(addr, mod)
3148 || within_module_init(addr, mod))
3149 return mod;
3150 return NULL;
3152 EXPORT_SYMBOL_GPL(__module_address);
3155 * is_module_text_address - is this address inside module code?
3156 * @addr: the address to check.
3158 * See is_module_address() if you simply want to see if the address is
3159 * anywhere in a module. See kernel_text_address() for testing if an
3160 * address corresponds to kernel or module code.
3162 bool is_module_text_address(unsigned long addr)
3164 bool ret;
3166 preempt_disable();
3167 ret = __module_text_address(addr) != NULL;
3168 preempt_enable();
3170 return ret;
3174 * __module_text_address - get the module whose code contains an address.
3175 * @addr: the address.
3177 * Must be called with preempt disabled or module mutex held so that
3178 * module doesn't get freed during this.
3180 struct module *__module_text_address(unsigned long addr)
3182 struct module *mod = __module_address(addr);
3183 if (mod) {
3184 /* Make sure it's within the text section. */
3185 if (!within(addr, mod->module_init, mod->init_text_size)
3186 && !within(addr, mod->module_core, mod->core_text_size))
3187 mod = NULL;
3189 return mod;
3191 EXPORT_SYMBOL_GPL(__module_text_address);
3193 /* Don't grab lock, we're oopsing. */
3194 void print_modules(void)
3196 struct module *mod;
3197 char buf[8];
3199 printk(KERN_DEFAULT "Modules linked in:");
3200 /* Most callers should already have preempt disabled, but make sure */
3201 preempt_disable();
3202 list_for_each_entry_rcu(mod, &modules, list)
3203 printk(" %s%s", mod->name, module_flags(mod, buf));
3204 preempt_enable();
3205 if (last_unloaded_module[0])
3206 printk(" [last unloaded: %s]", last_unloaded_module);
3207 printk("\n");
3210 #ifdef CONFIG_MODVERSIONS
3211 /* Generate the signature for all relevant module structures here.
3212 * If these change, we don't want to try to parse the module. */
3213 void module_layout(struct module *mod,
3214 struct modversion_info *ver,
3215 struct kernel_param *kp,
3216 struct kernel_symbol *ks,
3217 struct tracepoint *tp)
3220 EXPORT_SYMBOL(module_layout);
3221 #endif
3223 #ifdef CONFIG_TRACEPOINTS
3224 void module_update_tracepoints(void)
3226 struct module *mod;
3228 mutex_lock(&module_mutex);
3229 list_for_each_entry(mod, &modules, list)
3230 if (!mod->taints)
3231 tracepoint_update_probe_range(mod->tracepoints,
3232 mod->tracepoints + mod->num_tracepoints);
3233 mutex_unlock(&module_mutex);
3237 * Returns 0 if current not found.
3238 * Returns 1 if current found.
3240 int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3242 struct module *iter_mod;
3243 int found = 0;
3245 mutex_lock(&module_mutex);
3246 list_for_each_entry(iter_mod, &modules, list) {
3247 if (!iter_mod->taints) {
3249 * Sorted module list
3251 if (iter_mod < iter->module)
3252 continue;
3253 else if (iter_mod > iter->module)
3254 iter->tracepoint = NULL;
3255 found = tracepoint_get_iter_range(&iter->tracepoint,
3256 iter_mod->tracepoints,
3257 iter_mod->tracepoints
3258 + iter_mod->num_tracepoints);
3259 if (found) {
3260 iter->module = iter_mod;
3261 break;
3265 mutex_unlock(&module_mutex);
3266 return found;
3268 #endif