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Arjan van de Venf71d20e2006-06-28 04:26:45 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18*/
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/module.h>
20#include <linux/moduleloader.h>
Steven Rostedt6d723732009-04-10 14:53:50 -040021#include <linux/ftrace_event.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/init.h>
Alexey Dobriyanae84e322007-05-08 00:28:38 -070023#include <linux/kallsyms.h>
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +040024#include <linux/fs.h>
Roland McGrath6d760132007-10-16 23:26:40 -070025#include <linux/sysfs.h>
Randy Dunlap9f158332005-09-13 01:25:16 -070026#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/slab.h>
28#include <linux/vmalloc.h>
29#include <linux/elf.h>
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +040030#include <linux/proc_fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <linux/seq_file.h>
32#include <linux/syscalls.h>
33#include <linux/fcntl.h>
34#include <linux/rcupdate.h>
Randy.Dunlapc59ede72006-01-11 12:17:46 -080035#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036#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>
Al Virof6a57032006-10-18 01:47:25 -040042#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#include <linux/stop_machine.h>
44#include <linux/device.h>
Matt Domschc988d2b2005-06-23 22:05:15 -070045#include <linux/string.h>
Arjan van de Ven97d1f152006-03-23 03:00:24 -080046#include <linux/mutex.h>
Andi Kleend72b3752008-08-30 10:09:00 +020047#include <linux/rculist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070048#include <asm/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070049#include <asm/cacheflush.h>
Bernd Schmidteb8cdec2009-09-21 17:03:57 -070050#include <asm/mmu_context.h>
Sam Ravnborgb817f6f2006-06-09 21:53:55 +020051#include <linux/license.h>
Christoph Lameter6d762392008-02-08 04:18:42 -080052#include <asm/sections.h>
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -040053#include <linux/tracepoint.h>
Steven Rostedt90d595f2008-08-14 15:45:09 -040054#include <linux/ftrace.h>
Arjan van de Ven22a9d642009-01-07 08:45:46 -080055#include <linux/async.h>
Tejun Heofbf59bc2009-02-20 16:29:08 +090056#include <linux/percpu.h>
Catalin Marinas4f2294b2009-06-11 13:23:20 +010057#include <linux/kmemleak.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
Li Zefan7ead8b82009-08-17 16:56:28 +080059#define CREATE_TRACE_POINTS
60#include <trace/events/module.h>
61
Linus Torvalds1da177e2005-04-16 15:20:36 -070062#if 0
63#define DEBUGP printk
64#else
65#define DEBUGP(fmt , a...)
66#endif
67
68#ifndef ARCH_SHF_SMALL
69#define ARCH_SHF_SMALL 0
70#endif
71
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))
74
Rusty Russell75676502010-06-05 11:17:36 -060075/*
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.
Andi Kleend72b3752008-08-30 10:09:00 +020080 * (delete uses stop_machine/add uses RCU list operations). */
Tim Abbottc6b37802008-12-05 19:03:59 -050081DEFINE_MUTEX(module_mutex);
82EXPORT_SYMBOL_GPL(module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070083static LIST_HEAD(modules);
Jason Wessel67fc4e02010-05-20 21:04:21 -050084#ifdef CONFIG_KGDB_KDB
85struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
86#endif /* CONFIG_KGDB_KDB */
87
Linus Torvalds1da177e2005-04-16 15:20:36 -070088
Stephen Rothwell19e45292009-04-14 17:27:18 +100089/* Block module loading/unloading? */
90int modules_disabled = 0;
91
Rusty Russellc9a3ba52008-01-29 17:13:18 -050092/* Waiting for a module to finish initializing? */
93static DECLARE_WAIT_QUEUE_HEAD(module_wq);
94
Alan Sterne041c682006-03-27 01:16:30 -080095static BLOCKING_NOTIFIER_HEAD(module_notify_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
Rusty Russell75676502010-06-05 11:17:36 -060097/* Bounds of module allocation, for speeding __module_address.
98 * Protected by module_mutex. */
Rusty Russell3a642e92008-07-22 19:24:28 -050099static unsigned long module_addr_min = -1UL, module_addr_max = 0;
100
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101int register_module_notifier(struct notifier_block * nb)
102{
Alan Sterne041c682006-03-27 01:16:30 -0800103 return blocking_notifier_chain_register(&module_notify_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104}
105EXPORT_SYMBOL(register_module_notifier);
106
107int unregister_module_notifier(struct notifier_block * nb)
108{
Alan Sterne041c682006-03-27 01:16:30 -0800109 return blocking_notifier_chain_unregister(&module_notify_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110}
111EXPORT_SYMBOL(unregister_module_notifier);
112
Rusty Russelleded41c2010-08-05 12:59:07 -0600113struct load_info {
114 Elf_Ehdr *hdr;
115 unsigned long len;
116 Elf_Shdr *sechdrs;
117 char *secstrings, *args, *strtab;
Rusty Russelld9131882010-08-05 12:59:08 -0600118 unsigned long *strmap;
119 unsigned long symoffs, stroffs;
Rusty Russelleded41c2010-08-05 12:59:07 -0600120 struct {
121 unsigned int sym, str, mod, vers, info, pcpu;
122 } index;
123};
124
Matti Linnanvuori9a4b9702007-11-08 08:37:38 -0800125/* We require a truly strong try_module_get(): 0 means failure due to
126 ongoing or failed initialization etc. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127static inline int strong_try_module_get(struct module *mod)
128{
129 if (mod && mod->state == MODULE_STATE_COMING)
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500130 return -EBUSY;
131 if (try_module_get(mod))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 return 0;
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500133 else
134 return -ENOENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135}
136
Florin Malitafa3ba2e82006-10-11 01:21:48 -0700137static inline void add_taint_module(struct module *mod, unsigned flag)
138{
139 add_taint(flag);
Andi Kleen25ddbb12008-10-15 22:01:41 -0700140 mod->taints |= (1U << flag);
Florin Malitafa3ba2e82006-10-11 01:21:48 -0700141}
142
Robert P. J. Day02a3e592007-05-09 07:26:28 +0200143/*
144 * A thread that wants to hold a reference to a module only while it
145 * is running can call this to safely exit. nfsd and lockd use this.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 */
147void __module_put_and_exit(struct module *mod, long code)
148{
149 module_put(mod);
150 do_exit(code);
151}
152EXPORT_SYMBOL(__module_put_and_exit);
Daniel Walker22a8bde2007-10-18 03:06:07 -0700153
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154/* Find a module section: 0 means not found. */
155static unsigned int find_sec(Elf_Ehdr *hdr,
156 Elf_Shdr *sechdrs,
157 const char *secstrings,
158 const char *name)
159{
160 unsigned int i;
161
162 for (i = 1; i < hdr->e_shnum; i++)
163 /* Alloc bit cleared means "ignore it." */
164 if ((sechdrs[i].sh_flags & SHF_ALLOC)
165 && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
166 return i;
167 return 0;
168}
169
Rusty Russell5e458cc2008-10-22 10:00:13 -0500170/* Find a module section, or NULL. */
171static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
172 const char *secstrings, const char *name)
173{
174 /* Section 0 has sh_addr 0. */
175 return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
176}
177
178/* Find a module section, or NULL. Fill in number of "objects" in section. */
179static void *section_objs(Elf_Ehdr *hdr,
180 Elf_Shdr *sechdrs,
181 const char *secstrings,
182 const char *name,
183 size_t object_size,
184 unsigned int *num)
185{
186 unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);
187
188 /* Section 0 has sh_addr 0 and sh_size 0. */
189 *num = sechdrs[sec].sh_size / object_size;
190 return (void *)sechdrs[sec].sh_addr;
191}
192
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193/* Provided by the linker */
194extern const struct kernel_symbol __start___ksymtab[];
195extern const struct kernel_symbol __stop___ksymtab[];
196extern const struct kernel_symbol __start___ksymtab_gpl[];
197extern const struct kernel_symbol __stop___ksymtab_gpl[];
Greg Kroah-Hartman9f28bb72006-03-20 13:17:13 -0800198extern const struct kernel_symbol __start___ksymtab_gpl_future[];
199extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200extern const unsigned long __start___kcrctab[];
201extern const unsigned long __start___kcrctab_gpl[];
Greg Kroah-Hartman9f28bb72006-03-20 13:17:13 -0800202extern const unsigned long __start___kcrctab_gpl_future[];
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500203#ifdef CONFIG_UNUSED_SYMBOLS
204extern const struct kernel_symbol __start___ksymtab_unused[];
205extern const struct kernel_symbol __stop___ksymtab_unused[];
206extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
207extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700208extern const unsigned long __start___kcrctab_unused[];
209extern const unsigned long __start___kcrctab_unused_gpl[];
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500210#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211
212#ifndef CONFIG_MODVERSIONS
213#define symversion(base, idx) NULL
214#else
Andrew Mortonf83ca9f2006-03-28 01:56:20 -0800215#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216#endif
217
Rusty Russelldafd0942008-07-22 19:24:25 -0500218static bool each_symbol_in_section(const struct symsearch *arr,
219 unsigned int arrsize,
220 struct module *owner,
221 bool (*fn)(const struct symsearch *syms,
222 struct module *owner,
223 unsigned int symnum, void *data),
224 void *data)
Sam Ravnborg3fd68052006-02-08 21:16:45 +0100225{
Rusty Russelldafd0942008-07-22 19:24:25 -0500226 unsigned int i, j;
227
228 for (j = 0; j < arrsize; j++) {
229 for (i = 0; i < arr[j].stop - arr[j].start; i++)
230 if (fn(&arr[j], owner, i, data))
231 return true;
232 }
233
234 return false;
Sam Ravnborg3fd68052006-02-08 21:16:45 +0100235}
236
Rusty Russelldafd0942008-07-22 19:24:25 -0500237/* Returns true as soon as fn returns true, otherwise false. */
Tim Abbottc6b37802008-12-05 19:03:59 -0500238bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
239 unsigned int symnum, void *data), void *data)
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700240{
Rusty Russelldafd0942008-07-22 19:24:25 -0500241 struct module *mod;
Linus Torvalds44032e62010-08-05 12:59:05 -0600242 static const struct symsearch arr[] = {
Rusty Russelldafd0942008-07-22 19:24:25 -0500243 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
244 NOT_GPL_ONLY, false },
245 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
246 __start___kcrctab_gpl,
247 GPL_ONLY, false },
248 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
249 __start___kcrctab_gpl_future,
250 WILL_BE_GPL_ONLY, false },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500251#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500252 { __start___ksymtab_unused, __stop___ksymtab_unused,
253 __start___kcrctab_unused,
254 NOT_GPL_ONLY, true },
255 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
256 __start___kcrctab_unused_gpl,
257 GPL_ONLY, true },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500258#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500259 };
260
261 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
262 return true;
263
Andi Kleend72b3752008-08-30 10:09:00 +0200264 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russelldafd0942008-07-22 19:24:25 -0500265 struct symsearch arr[] = {
266 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
267 NOT_GPL_ONLY, false },
268 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
269 mod->gpl_crcs,
270 GPL_ONLY, false },
271 { mod->gpl_future_syms,
272 mod->gpl_future_syms + mod->num_gpl_future_syms,
273 mod->gpl_future_crcs,
274 WILL_BE_GPL_ONLY, false },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500275#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500276 { mod->unused_syms,
277 mod->unused_syms + mod->num_unused_syms,
278 mod->unused_crcs,
279 NOT_GPL_ONLY, true },
280 { mod->unused_gpl_syms,
281 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
282 mod->unused_gpl_crcs,
283 GPL_ONLY, true },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500284#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500285 };
286
287 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
288 return true;
289 }
290 return false;
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700291}
Tim Abbottc6b37802008-12-05 19:03:59 -0500292EXPORT_SYMBOL_GPL(each_symbol);
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700293
Rusty Russelldafd0942008-07-22 19:24:25 -0500294struct find_symbol_arg {
295 /* Input */
296 const char *name;
297 bool gplok;
298 bool warn;
299
300 /* Output */
301 struct module *owner;
302 const unsigned long *crc;
Tim Abbott414fd312008-12-05 19:03:56 -0500303 const struct kernel_symbol *sym;
Rusty Russelldafd0942008-07-22 19:24:25 -0500304};
305
306static bool find_symbol_in_section(const struct symsearch *syms,
307 struct module *owner,
308 unsigned int symnum, void *data)
Rusty Russellad9546c2008-05-01 21:14:59 -0500309{
Rusty Russelldafd0942008-07-22 19:24:25 -0500310 struct find_symbol_arg *fsa = data;
311
312 if (strcmp(syms->start[symnum].name, fsa->name) != 0)
313 return false;
314
315 if (!fsa->gplok) {
316 if (syms->licence == GPL_ONLY)
317 return false;
318 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
319 printk(KERN_WARNING "Symbol %s is being used "
320 "by a non-GPL module, which will not "
321 "be allowed in the future\n", fsa->name);
322 printk(KERN_WARNING "Please see the file "
323 "Documentation/feature-removal-schedule.txt "
324 "in the kernel source tree for more details.\n");
325 }
326 }
327
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500328#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500329 if (syms->unused && fsa->warn) {
Rusty Russellad9546c2008-05-01 21:14:59 -0500330 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
Rusty Russelldafd0942008-07-22 19:24:25 -0500331 "however this module is using it.\n", fsa->name);
Rusty Russellad9546c2008-05-01 21:14:59 -0500332 printk(KERN_WARNING
333 "This symbol will go away in the future.\n");
334 printk(KERN_WARNING
335 "Please evalute if this is the right api to use and if "
336 "it really is, submit a report the linux kernel "
337 "mailinglist together with submitting your code for "
338 "inclusion.\n");
339 }
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500340#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500341
342 fsa->owner = owner;
343 fsa->crc = symversion(syms->crcs, symnum);
Tim Abbott414fd312008-12-05 19:03:56 -0500344 fsa->sym = &syms->start[symnum];
Rusty Russellad9546c2008-05-01 21:14:59 -0500345 return true;
346}
347
Tim Abbott414fd312008-12-05 19:03:56 -0500348/* Find a symbol and return it, along with, (optional) crc and
Rusty Russell75676502010-06-05 11:17:36 -0600349 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
Tim Abbottc6b37802008-12-05 19:03:59 -0500350const struct kernel_symbol *find_symbol(const char *name,
351 struct module **owner,
352 const unsigned long **crc,
353 bool gplok,
354 bool warn)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355{
Rusty Russelldafd0942008-07-22 19:24:25 -0500356 struct find_symbol_arg fsa;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357
Rusty Russelldafd0942008-07-22 19:24:25 -0500358 fsa.name = name;
359 fsa.gplok = gplok;
360 fsa.warn = warn;
361
362 if (each_symbol(find_symbol_in_section, &fsa)) {
Rusty Russellad9546c2008-05-01 21:14:59 -0500363 if (owner)
Rusty Russelldafd0942008-07-22 19:24:25 -0500364 *owner = fsa.owner;
365 if (crc)
366 *crc = fsa.crc;
Tim Abbott414fd312008-12-05 19:03:56 -0500367 return fsa.sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 }
Rusty Russellad9546c2008-05-01 21:14:59 -0500369
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370 DEBUGP("Failed to find symbol %s\n", name);
Tim Abbott414fd312008-12-05 19:03:56 -0500371 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372}
Tim Abbottc6b37802008-12-05 19:03:59 -0500373EXPORT_SYMBOL_GPL(find_symbol);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375/* Search for module by name: must hold module_mutex. */
Tim Abbottc6b37802008-12-05 19:03:59 -0500376struct module *find_module(const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377{
378 struct module *mod;
379
380 list_for_each_entry(mod, &modules, list) {
381 if (strcmp(mod->name, name) == 0)
382 return mod;
383 }
384 return NULL;
385}
Tim Abbottc6b37802008-12-05 19:03:59 -0500386EXPORT_SYMBOL_GPL(find_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387
388#ifdef CONFIG_SMP
Tejun Heofbf59bc2009-02-20 16:29:08 +0900389
Tejun Heo259354d2010-03-10 18:56:10 +0900390static inline void __percpu *mod_percpu(struct module *mod)
Tejun Heofbf59bc2009-02-20 16:29:08 +0900391{
Tejun Heo259354d2010-03-10 18:56:10 +0900392 return mod->percpu;
393}
Tejun Heofbf59bc2009-02-20 16:29:08 +0900394
Tejun Heo259354d2010-03-10 18:56:10 +0900395static int percpu_modalloc(struct module *mod,
396 unsigned long size, unsigned long align)
397{
Tejun Heofbf59bc2009-02-20 16:29:08 +0900398 if (align > PAGE_SIZE) {
399 printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
Tejun Heo259354d2010-03-10 18:56:10 +0900400 mod->name, align, PAGE_SIZE);
Tejun Heofbf59bc2009-02-20 16:29:08 +0900401 align = PAGE_SIZE;
402 }
403
Tejun Heo259354d2010-03-10 18:56:10 +0900404 mod->percpu = __alloc_reserved_percpu(size, align);
405 if (!mod->percpu) {
Tejun Heofbf59bc2009-02-20 16:29:08 +0900406 printk(KERN_WARNING
Rusty Russelld9131882010-08-05 12:59:08 -0600407 "%s: Could not allocate %lu bytes percpu data\n",
408 mod->name, size);
Tejun Heo259354d2010-03-10 18:56:10 +0900409 return -ENOMEM;
410 }
411 mod->percpu_size = size;
412 return 0;
Tejun Heofbf59bc2009-02-20 16:29:08 +0900413}
414
Tejun Heo259354d2010-03-10 18:56:10 +0900415static void percpu_modfree(struct module *mod)
Tejun Heofbf59bc2009-02-20 16:29:08 +0900416{
Tejun Heo259354d2010-03-10 18:56:10 +0900417 free_percpu(mod->percpu);
Tejun Heofbf59bc2009-02-20 16:29:08 +0900418}
419
Tejun Heo6b588c12009-02-20 16:29:07 +0900420static unsigned int find_pcpusec(Elf_Ehdr *hdr,
421 Elf_Shdr *sechdrs,
422 const char *secstrings)
423{
Denys Vlasenko3d9a8542010-02-20 01:03:43 +0100424 return find_sec(hdr, sechdrs, secstrings, ".data..percpu");
Tejun Heo6b588c12009-02-20 16:29:07 +0900425}
426
Tejun Heo259354d2010-03-10 18:56:10 +0900427static void percpu_modcopy(struct module *mod,
428 const void *from, unsigned long size)
Tejun Heo6b588c12009-02-20 16:29:07 +0900429{
430 int cpu;
431
432 for_each_possible_cpu(cpu)
Tejun Heo259354d2010-03-10 18:56:10 +0900433 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
Tejun Heo6b588c12009-02-20 16:29:07 +0900434}
435
Tejun Heo10fad5e2010-03-10 18:57:54 +0900436/**
437 * is_module_percpu_address - test whether address is from module static percpu
438 * @addr: address to test
439 *
440 * Test whether @addr belongs to module static percpu area.
441 *
442 * RETURNS:
443 * %true if @addr is from module static percpu area
444 */
445bool is_module_percpu_address(unsigned long addr)
446{
447 struct module *mod;
448 unsigned int cpu;
449
450 preempt_disable();
451
452 list_for_each_entry_rcu(mod, &modules, list) {
453 if (!mod->percpu_size)
454 continue;
455 for_each_possible_cpu(cpu) {
456 void *start = per_cpu_ptr(mod->percpu, cpu);
457
458 if ((void *)addr >= start &&
459 (void *)addr < start + mod->percpu_size) {
460 preempt_enable();
461 return true;
462 }
463 }
464 }
465
466 preempt_enable();
467 return false;
Daniel Walker22a8bde2007-10-18 03:06:07 -0700468}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469
470#else /* ... !CONFIG_SMP */
Tejun Heo6b588c12009-02-20 16:29:07 +0900471
Tejun Heo259354d2010-03-10 18:56:10 +0900472static inline void __percpu *mod_percpu(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473{
474 return NULL;
475}
Tejun Heo259354d2010-03-10 18:56:10 +0900476static inline int percpu_modalloc(struct module *mod,
477 unsigned long size, unsigned long align)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478{
Tejun Heo259354d2010-03-10 18:56:10 +0900479 return -ENOMEM;
480}
481static inline void percpu_modfree(struct module *mod)
482{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483}
484static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
485 Elf_Shdr *sechdrs,
486 const char *secstrings)
487{
488 return 0;
489}
Tejun Heo259354d2010-03-10 18:56:10 +0900490static inline void percpu_modcopy(struct module *mod,
491 const void *from, unsigned long size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492{
493 /* pcpusec should be 0, and size of that section should be 0. */
494 BUG_ON(size != 0);
495}
Tejun Heo10fad5e2010-03-10 18:57:54 +0900496bool is_module_percpu_address(unsigned long addr)
497{
498 return false;
499}
Tejun Heo6b588c12009-02-20 16:29:07 +0900500
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501#endif /* CONFIG_SMP */
502
Matt Domschc988d2b2005-06-23 22:05:15 -0700503#define MODINFO_ATTR(field) \
504static void setup_modinfo_##field(struct module *mod, const char *s) \
505{ \
506 mod->field = kstrdup(s, GFP_KERNEL); \
507} \
508static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
509 struct module *mod, char *buffer) \
510{ \
511 return sprintf(buffer, "%s\n", mod->field); \
512} \
513static int modinfo_##field##_exists(struct module *mod) \
514{ \
515 return mod->field != NULL; \
516} \
517static void free_modinfo_##field(struct module *mod) \
518{ \
Daniel Walker22a8bde2007-10-18 03:06:07 -0700519 kfree(mod->field); \
520 mod->field = NULL; \
Matt Domschc988d2b2005-06-23 22:05:15 -0700521} \
522static struct module_attribute modinfo_##field = { \
Tejun Heo7b595752007-06-14 03:45:17 +0900523 .attr = { .name = __stringify(field), .mode = 0444 }, \
Matt Domschc988d2b2005-06-23 22:05:15 -0700524 .show = show_modinfo_##field, \
525 .setup = setup_modinfo_##field, \
526 .test = modinfo_##field##_exists, \
527 .free = free_modinfo_##field, \
528};
529
530MODINFO_ATTR(version);
531MODINFO_ATTR(srcversion);
532
Arjan van de Vene14af7e2008-01-25 21:08:33 +0100533static char last_unloaded_module[MODULE_NAME_LEN+1];
534
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -0800535#ifdef CONFIG_MODULE_UNLOAD
Steven Rostedteb0c5372010-03-29 14:25:18 -0400536
537EXPORT_TRACEPOINT_SYMBOL(module_get);
538
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539/* Init the unload section of the module. */
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600540static int module_unload_init(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541{
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600542 mod->refptr = alloc_percpu(struct module_ref);
543 if (!mod->refptr)
544 return -ENOMEM;
545
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700546 INIT_LIST_HEAD(&mod->source_list);
547 INIT_LIST_HEAD(&mod->target_list);
Christoph Lametere1783a22010-01-05 15:34:50 +0900548
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 /* Hold reference count during initialization. */
Nick Piggin5fbfb182010-04-01 19:09:40 +1100550 __this_cpu_write(mod->refptr->incs, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551 /* Backwards compatibility macros put refcount during init. */
552 mod->waiter = current;
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600553
554 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555}
556
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557/* Does a already use b? */
558static int already_uses(struct module *a, struct module *b)
559{
560 struct module_use *use;
561
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700562 list_for_each_entry(use, &b->source_list, source_list) {
563 if (use->source == a) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564 DEBUGP("%s uses %s!\n", a->name, b->name);
565 return 1;
566 }
567 }
568 DEBUGP("%s does not use %s!\n", a->name, b->name);
569 return 0;
570}
571
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700572/*
573 * Module a uses b
574 * - we add 'a' as a "source", 'b' as a "target" of module use
575 * - the module_use is added to the list of 'b' sources (so
576 * 'b' can walk the list to see who sourced them), and of 'a'
577 * targets (so 'a' can see what modules it targets).
578 */
579static int add_module_usage(struct module *a, struct module *b)
580{
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700581 struct module_use *use;
582
583 DEBUGP("Allocating new usage for %s.\n", a->name);
584 use = kmalloc(sizeof(*use), GFP_ATOMIC);
585 if (!use) {
586 printk(KERN_WARNING "%s: out of memory loading\n", a->name);
587 return -ENOMEM;
588 }
589
590 use->source = a;
591 use->target = b;
592 list_add(&use->source_list, &b->source_list);
593 list_add(&use->target_list, &a->target_list);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700594 return 0;
595}
596
Rusty Russell75676502010-06-05 11:17:36 -0600597/* Module a uses b: caller needs module_mutex() */
Rusty Russell9bea7f22010-06-05 11:17:37 -0600598int ref_module(struct module *a, struct module *b)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599{
Rusty Russellc8e21ce2010-06-05 11:17:35 -0600600 int err;
Kay Sievers270a6c42007-01-18 13:26:15 +0100601
Rusty Russell9bea7f22010-06-05 11:17:37 -0600602 if (b == NULL || already_uses(a, b))
Linus Torvalds218ce732010-05-25 16:48:30 -0700603 return 0;
Linus Torvalds218ce732010-05-25 16:48:30 -0700604
Rusty Russell9bea7f22010-06-05 11:17:37 -0600605 /* If module isn't available, we fail. */
606 err = strong_try_module_get(b);
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500607 if (err)
Rusty Russell9bea7f22010-06-05 11:17:37 -0600608 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700610 err = add_module_usage(a, b);
611 if (err) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 module_put(b);
Rusty Russell9bea7f22010-06-05 11:17:37 -0600613 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614 }
Rusty Russell9bea7f22010-06-05 11:17:37 -0600615 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616}
Rusty Russell9bea7f22010-06-05 11:17:37 -0600617EXPORT_SYMBOL_GPL(ref_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618
619/* Clear the unload stuff of the module. */
620static void module_unload_free(struct module *mod)
621{
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700622 struct module_use *use, *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623
Rusty Russell75676502010-06-05 11:17:36 -0600624 mutex_lock(&module_mutex);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700625 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
626 struct module *i = use->target;
627 DEBUGP("%s unusing %s\n", mod->name, i->name);
628 module_put(i);
629 list_del(&use->source_list);
630 list_del(&use->target_list);
631 kfree(use);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632 }
Rusty Russell75676502010-06-05 11:17:36 -0600633 mutex_unlock(&module_mutex);
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600634
635 free_percpu(mod->refptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636}
637
638#ifdef CONFIG_MODULE_FORCE_UNLOAD
Akinobu Mitafb169792006-01-08 01:04:29 -0800639static inline int try_force_unload(unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640{
641 int ret = (flags & O_TRUNC);
642 if (ret)
Akinobu Mitafb169792006-01-08 01:04:29 -0800643 add_taint(TAINT_FORCED_RMMOD);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644 return ret;
645}
646#else
Akinobu Mitafb169792006-01-08 01:04:29 -0800647static inline int try_force_unload(unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648{
649 return 0;
650}
651#endif /* CONFIG_MODULE_FORCE_UNLOAD */
652
653struct stopref
654{
655 struct module *mod;
656 int flags;
657 int *forced;
658};
659
660/* Whole machine is stopped with interrupts off when this runs. */
661static int __try_stop_module(void *_sref)
662{
663 struct stopref *sref = _sref;
664
Rusty Russellda39ba52008-07-22 19:24:25 -0500665 /* If it's not unused, quit unless we're forcing. */
666 if (module_refcount(sref->mod) != 0) {
Akinobu Mitafb169792006-01-08 01:04:29 -0800667 if (!(*sref->forced = try_force_unload(sref->flags)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 return -EWOULDBLOCK;
669 }
670
671 /* Mark it as dying. */
672 sref->mod->state = MODULE_STATE_GOING;
673 return 0;
674}
675
676static int try_stop_module(struct module *mod, int flags, int *forced)
677{
Rusty Russellda39ba52008-07-22 19:24:25 -0500678 if (flags & O_NONBLOCK) {
679 struct stopref sref = { mod, flags, forced };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680
Rusty Russell9b1a4d32008-07-28 12:16:30 -0500681 return stop_machine(__try_stop_module, &sref, NULL);
Rusty Russellda39ba52008-07-22 19:24:25 -0500682 } else {
683 /* We don't need to stop the machine for this. */
684 mod->state = MODULE_STATE_GOING;
685 synchronize_sched();
686 return 0;
687 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688}
689
690unsigned int module_refcount(struct module *mod)
691{
Nick Piggin5fbfb182010-04-01 19:09:40 +1100692 unsigned int incs = 0, decs = 0;
Eric Dumazet720eba32009-02-03 13:31:36 +1030693 int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694
Eric Dumazet720eba32009-02-03 13:31:36 +1030695 for_each_possible_cpu(cpu)
Nick Piggin5fbfb182010-04-01 19:09:40 +1100696 decs += per_cpu_ptr(mod->refptr, cpu)->decs;
697 /*
698 * ensure the incs are added up after the decs.
699 * module_put ensures incs are visible before decs with smp_wmb.
700 *
701 * This 2-count scheme avoids the situation where the refcount
702 * for CPU0 is read, then CPU0 increments the module refcount,
703 * then CPU1 drops that refcount, then the refcount for CPU1 is
704 * read. We would record a decrement but not its corresponding
705 * increment so we would see a low count (disaster).
706 *
707 * Rare situation? But module_refcount can be preempted, and we
708 * might be tallying up 4096+ CPUs. So it is not impossible.
709 */
710 smp_rmb();
711 for_each_possible_cpu(cpu)
712 incs += per_cpu_ptr(mod->refptr, cpu)->incs;
713 return incs - decs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714}
715EXPORT_SYMBOL(module_refcount);
716
717/* This exists whether we can unload or not */
718static void free_module(struct module *mod);
719
720static void wait_for_zero_refcount(struct module *mod)
721{
Matthew Wilcoxa6550202008-02-26 10:47:18 -0500722 /* Since we might sleep for some time, release the mutex first */
Ashutosh Naik6389a382006-03-23 03:00:46 -0800723 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724 for (;;) {
725 DEBUGP("Looking at refcount...\n");
726 set_current_state(TASK_UNINTERRUPTIBLE);
727 if (module_refcount(mod) == 0)
728 break;
729 schedule();
730 }
731 current->state = TASK_RUNNING;
Ashutosh Naik6389a382006-03-23 03:00:46 -0800732 mutex_lock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733}
734
Heiko Carstens17da2bd2009-01-14 14:14:10 +0100735SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
736 unsigned int, flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737{
738 struct module *mod;
Greg Kroah-Hartmandfff0a02007-02-23 14:54:57 -0800739 char name[MODULE_NAME_LEN];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740 int ret, forced = 0;
741
Kees Cook3d433212009-04-02 15:49:29 -0700742 if (!capable(CAP_SYS_MODULE) || modules_disabled)
Greg Kroah-Hartmandfff0a02007-02-23 14:54:57 -0800743 return -EPERM;
744
745 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
746 return -EFAULT;
747 name[MODULE_NAME_LEN-1] = '\0';
748
Tejun Heo3fc1f1e2010-05-06 18:49:20 +0200749 if (mutex_lock_interruptible(&module_mutex) != 0)
750 return -EINTR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751
752 mod = find_module(name);
753 if (!mod) {
754 ret = -ENOENT;
755 goto out;
756 }
757
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700758 if (!list_empty(&mod->source_list)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759 /* Other modules depend on us: get rid of them first. */
760 ret = -EWOULDBLOCK;
761 goto out;
762 }
763
764 /* Doing init or already dying? */
765 if (mod->state != MODULE_STATE_LIVE) {
766 /* FIXME: if (force), slam module count and wake up
767 waiter --RR */
768 DEBUGP("%s already dying\n", mod->name);
769 ret = -EBUSY;
770 goto out;
771 }
772
773 /* If it has an init func, it must have an exit func to unload */
Rusty Russellaf49d922007-10-16 23:26:27 -0700774 if (mod->init && !mod->exit) {
Akinobu Mitafb169792006-01-08 01:04:29 -0800775 forced = try_force_unload(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 if (!forced) {
777 /* This module can't be removed */
778 ret = -EBUSY;
779 goto out;
780 }
781 }
782
783 /* Set this up before setting mod->state */
784 mod->waiter = current;
785
786 /* Stop the machine so refcounts can't move and disable module. */
787 ret = try_stop_module(mod, flags, &forced);
788 if (ret != 0)
789 goto out;
790
791 /* Never wait if forced. */
792 if (!forced && module_refcount(mod) != 0)
793 wait_for_zero_refcount(mod);
794
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +0200795 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 /* Final destruction now noone is using it. */
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +0200797 if (mod->exit != NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798 mod->exit();
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +0200799 blocking_notifier_call_chain(&module_notify_list,
800 MODULE_STATE_GOING, mod);
Arjan van de Ven22a9d642009-01-07 08:45:46 -0800801 async_synchronize_full();
Rusty Russell75676502010-06-05 11:17:36 -0600802
Arjan van de Vene14af7e2008-01-25 21:08:33 +0100803 /* Store the name of the last unloaded module for diagnostic purposes */
Rusty Russellefa53452008-01-29 17:13:20 -0500804 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805
Rusty Russell75676502010-06-05 11:17:36 -0600806 free_module(mod);
807 return 0;
808out:
Ashutosh Naik6389a382006-03-23 03:00:46 -0800809 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810 return ret;
811}
812
Jianjun Kongd1e99d72008-12-08 14:26:29 +0800813static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814{
815 struct module_use *use;
816 int printed_something = 0;
817
818 seq_printf(m, " %u ", module_refcount(mod));
819
820 /* Always include a trailing , so userspace can differentiate
821 between this and the old multi-field proc format. */
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700822 list_for_each_entry(use, &mod->source_list, source_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700823 printed_something = 1;
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700824 seq_printf(m, "%s,", use->source->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825 }
826
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827 if (mod->init != NULL && mod->exit == NULL) {
828 printed_something = 1;
829 seq_printf(m, "[permanent],");
830 }
831
832 if (!printed_something)
833 seq_printf(m, "-");
834}
835
836void __symbol_put(const char *symbol)
837{
838 struct module *owner;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839
Rusty Russell24da1cb2007-07-15 23:41:46 -0700840 preempt_disable();
Tim Abbott414fd312008-12-05 19:03:56 -0500841 if (!find_symbol(symbol, &owner, NULL, true, false))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842 BUG();
843 module_put(owner);
Rusty Russell24da1cb2007-07-15 23:41:46 -0700844 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845}
846EXPORT_SYMBOL(__symbol_put);
847
Rusty Russell7d1d16e2009-08-26 22:02:54 +0930848/* Note this assumes addr is a function, which it currently always is. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849void symbol_put_addr(void *addr)
850{
Trent Piepho5e376612006-05-15 09:44:06 -0700851 struct module *modaddr;
Rusty Russell7d1d16e2009-08-26 22:02:54 +0930852 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853
Rusty Russell7d1d16e2009-08-26 22:02:54 +0930854 if (core_kernel_text(a))
Trent Piepho5e376612006-05-15 09:44:06 -0700855 return;
856
Rusty Russella6e6abd2009-03-31 13:05:31 -0600857 /* module_text_address is safe here: we're supposed to have reference
858 * to module from symbol_get, so it can't go away. */
Rusty Russell7d1d16e2009-08-26 22:02:54 +0930859 modaddr = __module_text_address(a);
Rusty Russella6e6abd2009-03-31 13:05:31 -0600860 BUG_ON(!modaddr);
Trent Piepho5e376612006-05-15 09:44:06 -0700861 module_put(modaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862}
863EXPORT_SYMBOL_GPL(symbol_put_addr);
864
865static ssize_t show_refcnt(struct module_attribute *mattr,
866 struct module *mod, char *buffer)
867{
Alexey Dobriyan256e2fd2007-08-06 23:47:45 +0400868 return sprintf(buffer, "%u\n", module_refcount(mod));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869}
870
871static struct module_attribute refcnt = {
Tejun Heo7b595752007-06-14 03:45:17 +0900872 .attr = { .name = "refcnt", .mode = 0444 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873 .show = show_refcnt,
874};
875
Al Virof6a57032006-10-18 01:47:25 -0400876void module_put(struct module *module)
877{
878 if (module) {
Christoph Lametere1783a22010-01-05 15:34:50 +0900879 preempt_disable();
Nick Piggin5fbfb182010-04-01 19:09:40 +1100880 smp_wmb(); /* see comment in module_refcount */
881 __this_cpu_inc(module->refptr->decs);
Christoph Lametere1783a22010-01-05 15:34:50 +0900882
Li Zefanae832d12010-03-24 10:57:43 +0800883 trace_module_put(module, _RET_IP_);
Al Virof6a57032006-10-18 01:47:25 -0400884 /* Maybe they're waiting for us to drop reference? */
885 if (unlikely(!module_is_live(module)))
886 wake_up_process(module->waiter);
Christoph Lametere1783a22010-01-05 15:34:50 +0900887 preempt_enable();
Al Virof6a57032006-10-18 01:47:25 -0400888 }
889}
890EXPORT_SYMBOL(module_put);
891
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892#else /* !CONFIG_MODULE_UNLOAD */
Jianjun Kongd1e99d72008-12-08 14:26:29 +0800893static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894{
895 /* We don't know the usage count, or what modules are using. */
896 seq_printf(m, " - -");
897}
898
899static inline void module_unload_free(struct module *mod)
900{
901}
902
Rusty Russell9bea7f22010-06-05 11:17:37 -0600903int ref_module(struct module *a, struct module *b)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904{
Rusty Russell9bea7f22010-06-05 11:17:37 -0600905 return strong_try_module_get(b);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906}
Rusty Russell9bea7f22010-06-05 11:17:37 -0600907EXPORT_SYMBOL_GPL(ref_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600909static inline int module_unload_init(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700910{
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600911 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912}
913#endif /* CONFIG_MODULE_UNLOAD */
914
Kay Sievers1f717402006-11-24 12:15:25 +0100915static ssize_t show_initstate(struct module_attribute *mattr,
916 struct module *mod, char *buffer)
917{
918 const char *state = "unknown";
919
920 switch (mod->state) {
921 case MODULE_STATE_LIVE:
922 state = "live";
923 break;
924 case MODULE_STATE_COMING:
925 state = "coming";
926 break;
927 case MODULE_STATE_GOING:
928 state = "going";
929 break;
930 }
931 return sprintf(buffer, "%s\n", state);
932}
933
934static struct module_attribute initstate = {
Tejun Heo7b595752007-06-14 03:45:17 +0900935 .attr = { .name = "initstate", .mode = 0444 },
Kay Sievers1f717402006-11-24 12:15:25 +0100936 .show = show_initstate,
937};
938
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -0800939static struct module_attribute *modinfo_attrs[] = {
940 &modinfo_version,
941 &modinfo_srcversion,
Kay Sievers1f717402006-11-24 12:15:25 +0100942 &initstate,
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -0800943#ifdef CONFIG_MODULE_UNLOAD
944 &refcnt,
945#endif
946 NULL,
947};
948
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949static const char vermagic[] = VERMAGIC_STRING;
950
Rusty Russellc6e665c2009-03-31 13:05:33 -0600951static int try_to_force_load(struct module *mod, const char *reason)
Linus Torvalds826e4502008-05-04 17:04:16 -0700952{
953#ifdef CONFIG_MODULE_FORCE_LOAD
Andi Kleen25ddbb12008-10-15 22:01:41 -0700954 if (!test_taint(TAINT_FORCED_MODULE))
Rusty Russellc6e665c2009-03-31 13:05:33 -0600955 printk(KERN_WARNING "%s: %s: kernel tainted.\n",
956 mod->name, reason);
Linus Torvalds826e4502008-05-04 17:04:16 -0700957 add_taint_module(mod, TAINT_FORCED_MODULE);
958 return 0;
959#else
960 return -ENOEXEC;
961#endif
962}
963
Linus Torvalds1da177e2005-04-16 15:20:36 -0700964#ifdef CONFIG_MODVERSIONS
Rusty Russelld4703ae2009-12-15 16:28:32 -0600965/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
966static unsigned long maybe_relocated(unsigned long crc,
967 const struct module *crc_owner)
968{
969#ifdef ARCH_RELOCATES_KCRCTAB
970 if (crc_owner == NULL)
971 return crc - (unsigned long)reloc_start;
972#endif
973 return crc;
974}
975
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976static int check_version(Elf_Shdr *sechdrs,
977 unsigned int versindex,
978 const char *symname,
979 struct module *mod,
Rusty Russelld4703ae2009-12-15 16:28:32 -0600980 const unsigned long *crc,
981 const struct module *crc_owner)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700982{
983 unsigned int i, num_versions;
984 struct modversion_info *versions;
985
986 /* Exporting module didn't supply crcs? OK, we're already tainted. */
987 if (!crc)
988 return 1;
989
Rusty Russella5dd6972008-05-09 16:24:21 +1000990 /* No versions at all? modprobe --force does this. */
991 if (versindex == 0)
992 return try_to_force_load(mod, symname) == 0;
993
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994 versions = (void *) sechdrs[versindex].sh_addr;
995 num_versions = sechdrs[versindex].sh_size
996 / sizeof(struct modversion_info);
997
998 for (i = 0; i < num_versions; i++) {
999 if (strcmp(versions[i].name, symname) != 0)
1000 continue;
1001
Rusty Russelld4703ae2009-12-15 16:28:32 -06001002 if (versions[i].crc == maybe_relocated(*crc, crc_owner))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001003 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 DEBUGP("Found checksum %lX vs module %lX\n",
Rusty Russelld4703ae2009-12-15 16:28:32 -06001005 maybe_relocated(*crc, crc_owner), versions[i].crc);
Linus Torvalds826e4502008-05-04 17:04:16 -07001006 goto bad_version;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001007 }
Linus Torvalds826e4502008-05-04 17:04:16 -07001008
Rusty Russella5dd6972008-05-09 16:24:21 +10001009 printk(KERN_WARNING "%s: no symbol version for %s\n",
1010 mod->name, symname);
1011 return 0;
Linus Torvalds826e4502008-05-04 17:04:16 -07001012
1013bad_version:
1014 printk("%s: disagrees about version of symbol %s\n",
1015 mod->name, symname);
1016 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001017}
1018
1019static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1020 unsigned int versindex,
1021 struct module *mod)
1022{
1023 const unsigned long *crc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001024
Rusty Russell75676502010-06-05 11:17:36 -06001025 /* Since this should be found in kernel (which can't be removed),
1026 * no locking is necessary. */
Mike Frysinger6560dc12009-07-23 23:42:08 +09301027 if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
1028 &crc, true, false))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001029 BUG();
Rusty Russelld4703ae2009-12-15 16:28:32 -06001030 return check_version(sechdrs, versindex, "module_layout", mod, crc,
1031 NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001032}
1033
Rusty Russell91e37a72008-05-09 16:25:28 +10001034/* First part is kernel version, which we ignore if module has crcs. */
1035static inline int same_magic(const char *amagic, const char *bmagic,
1036 bool has_crcs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001037{
Rusty Russell91e37a72008-05-09 16:25:28 +10001038 if (has_crcs) {
1039 amagic += strcspn(amagic, " ");
1040 bmagic += strcspn(bmagic, " ");
1041 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001042 return strcmp(amagic, bmagic) == 0;
1043}
1044#else
1045static inline int check_version(Elf_Shdr *sechdrs,
1046 unsigned int versindex,
1047 const char *symname,
1048 struct module *mod,
Rusty Russelld4703ae2009-12-15 16:28:32 -06001049 const unsigned long *crc,
1050 const struct module *crc_owner)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051{
1052 return 1;
1053}
1054
1055static inline int check_modstruct_version(Elf_Shdr *sechdrs,
1056 unsigned int versindex,
1057 struct module *mod)
1058{
1059 return 1;
1060}
1061
Rusty Russell91e37a72008-05-09 16:25:28 +10001062static inline int same_magic(const char *amagic, const char *bmagic,
1063 bool has_crcs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001064{
1065 return strcmp(amagic, bmagic) == 0;
1066}
1067#endif /* CONFIG_MODVERSIONS */
1068
Rusty Russell75676502010-06-05 11:17:36 -06001069/* Resolve a symbol for this module. I.e. if we find one, record usage. */
Tim Abbott414fd312008-12-05 19:03:56 -05001070static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
1071 unsigned int versindex,
1072 const char *name,
Rusty Russell9bea7f22010-06-05 11:17:37 -06001073 struct module *mod,
1074 char ownername[])
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075{
1076 struct module *owner;
Tim Abbott414fd312008-12-05 19:03:56 -05001077 const struct kernel_symbol *sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078 const unsigned long *crc;
Rusty Russell9bea7f22010-06-05 11:17:37 -06001079 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001080
Rusty Russell75676502010-06-05 11:17:36 -06001081 mutex_lock(&module_mutex);
Tim Abbott414fd312008-12-05 19:03:56 -05001082 sym = find_symbol(name, &owner, &crc,
Andi Kleen25ddbb12008-10-15 22:01:41 -07001083 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
Rusty Russell9bea7f22010-06-05 11:17:37 -06001084 if (!sym)
1085 goto unlock;
1086
1087 if (!check_version(sechdrs, versindex, name, mod, crc, owner)) {
1088 sym = ERR_PTR(-EINVAL);
1089 goto getname;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090 }
Rusty Russell9bea7f22010-06-05 11:17:37 -06001091
1092 err = ref_module(mod, owner);
1093 if (err) {
1094 sym = ERR_PTR(err);
1095 goto getname;
1096 }
1097
1098getname:
1099 /* We must make copy under the lock if we failed to get ref. */
1100 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1101unlock:
Rusty Russell75676502010-06-05 11:17:36 -06001102 mutex_unlock(&module_mutex);
Linus Torvalds218ce732010-05-25 16:48:30 -07001103 return sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001104}
1105
Rusty Russell9bea7f22010-06-05 11:17:37 -06001106static const struct kernel_symbol *resolve_symbol_wait(Elf_Shdr *sechdrs,
1107 unsigned int versindex,
1108 const char *name,
1109 struct module *mod)
1110{
1111 const struct kernel_symbol *ksym;
1112 char ownername[MODULE_NAME_LEN];
1113
1114 if (wait_event_interruptible_timeout(module_wq,
1115 !IS_ERR(ksym = resolve_symbol(sechdrs, versindex, name,
1116 mod, ownername)) ||
1117 PTR_ERR(ksym) != -EBUSY,
1118 30 * HZ) <= 0) {
1119 printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
1120 mod->name, ownername);
1121 }
1122 return ksym;
1123}
1124
Linus Torvalds1da177e2005-04-16 15:20:36 -07001125/*
1126 * /sys/module/foo/sections stuff
1127 * J. Corbet <corbet@lwn.net>
1128 */
Rusty Russell8f6d0372010-08-05 12:59:09 -06001129#ifdef CONFIG_SYSFS
Ben Hutchings10b465a2009-12-19 14:43:01 +00001130
Rusty Russell8f6d0372010-08-05 12:59:09 -06001131#ifdef CONFIG_KALLSYMS
Ben Hutchings10b465a2009-12-19 14:43:01 +00001132static inline bool sect_empty(const Elf_Shdr *sect)
1133{
1134 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1135}
1136
Rusty Russella58730c2008-03-13 09:03:44 +00001137struct module_sect_attr
1138{
1139 struct module_attribute mattr;
1140 char *name;
1141 unsigned long address;
1142};
1143
1144struct module_sect_attrs
1145{
1146 struct attribute_group grp;
1147 unsigned int nsections;
1148 struct module_sect_attr attrs[0];
1149};
1150
Linus Torvalds1da177e2005-04-16 15:20:36 -07001151static ssize_t module_sect_show(struct module_attribute *mattr,
1152 struct module *mod, char *buf)
1153{
1154 struct module_sect_attr *sattr =
1155 container_of(mattr, struct module_sect_attr, mattr);
1156 return sprintf(buf, "0x%lx\n", sattr->address);
1157}
1158
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001159static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1160{
Rusty Russella58730c2008-03-13 09:03:44 +00001161 unsigned int section;
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001162
1163 for (section = 0; section < sect_attrs->nsections; section++)
1164 kfree(sect_attrs->attrs[section].name);
1165 kfree(sect_attrs);
1166}
1167
Rusty Russell8f6d0372010-08-05 12:59:09 -06001168static void add_sect_attrs(struct module *mod, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001169{
1170 unsigned int nloaded = 0, i, size[2];
1171 struct module_sect_attrs *sect_attrs;
1172 struct module_sect_attr *sattr;
1173 struct attribute **gattr;
Daniel Walker22a8bde2007-10-18 03:06:07 -07001174
Linus Torvalds1da177e2005-04-16 15:20:36 -07001175 /* Count loaded sections and allocate structures */
Rusty Russell8f6d0372010-08-05 12:59:09 -06001176 for (i = 0; i < info->hdr->e_shnum; i++)
1177 if (!sect_empty(&info->sechdrs[i]))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178 nloaded++;
1179 size[0] = ALIGN(sizeof(*sect_attrs)
1180 + nloaded * sizeof(sect_attrs->attrs[0]),
1181 sizeof(sect_attrs->grp.attrs[0]));
1182 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001183 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1184 if (sect_attrs == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001185 return;
1186
1187 /* Setup section attributes. */
1188 sect_attrs->grp.name = "sections";
1189 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1190
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001191 sect_attrs->nsections = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001192 sattr = &sect_attrs->attrs[0];
1193 gattr = &sect_attrs->grp.attrs[0];
Rusty Russell8f6d0372010-08-05 12:59:09 -06001194 for (i = 0; i < info->hdr->e_shnum; i++) {
1195 Elf_Shdr *sec = &info->sechdrs[i];
1196 if (sect_empty(sec))
Helge Deller35dead42009-12-03 00:29:15 +01001197 continue;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001198 sattr->address = sec->sh_addr;
1199 sattr->name = kstrdup(info->secstrings + sec->sh_name,
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001200 GFP_KERNEL);
1201 if (sattr->name == NULL)
1202 goto out;
1203 sect_attrs->nsections++;
Eric W. Biederman361795b2010-02-12 13:41:56 -08001204 sysfs_attr_init(&sattr->mattr.attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001205 sattr->mattr.show = module_sect_show;
1206 sattr->mattr.store = NULL;
1207 sattr->mattr.attr.name = sattr->name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001208 sattr->mattr.attr.mode = S_IRUGO;
1209 *(gattr++) = &(sattr++)->mattr.attr;
1210 }
1211 *gattr = NULL;
1212
1213 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1214 goto out;
1215
1216 mod->sect_attrs = sect_attrs;
1217 return;
1218 out:
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001219 free_sect_attrs(sect_attrs);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001220}
1221
1222static void remove_sect_attrs(struct module *mod)
1223{
1224 if (mod->sect_attrs) {
1225 sysfs_remove_group(&mod->mkobj.kobj,
1226 &mod->sect_attrs->grp);
1227 /* We are positive that no one is using any sect attrs
1228 * at this point. Deallocate immediately. */
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001229 free_sect_attrs(mod->sect_attrs);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001230 mod->sect_attrs = NULL;
1231 }
1232}
1233
Roland McGrath6d760132007-10-16 23:26:40 -07001234/*
1235 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1236 */
1237
1238struct module_notes_attrs {
1239 struct kobject *dir;
1240 unsigned int notes;
1241 struct bin_attribute attrs[0];
1242};
1243
Chris Wright2c3c8be2010-05-12 18:28:57 -07001244static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
Roland McGrath6d760132007-10-16 23:26:40 -07001245 struct bin_attribute *bin_attr,
1246 char *buf, loff_t pos, size_t count)
1247{
1248 /*
1249 * The caller checked the pos and count against our size.
1250 */
1251 memcpy(buf, bin_attr->private + pos, count);
1252 return count;
1253}
1254
1255static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1256 unsigned int i)
1257{
1258 if (notes_attrs->dir) {
1259 while (i-- > 0)
1260 sysfs_remove_bin_file(notes_attrs->dir,
1261 &notes_attrs->attrs[i]);
Alexey Dobriyane9432092008-09-23 23:51:11 +04001262 kobject_put(notes_attrs->dir);
Roland McGrath6d760132007-10-16 23:26:40 -07001263 }
1264 kfree(notes_attrs);
1265}
1266
Rusty Russell8f6d0372010-08-05 12:59:09 -06001267static void add_notes_attrs(struct module *mod, const struct load_info *info)
Roland McGrath6d760132007-10-16 23:26:40 -07001268{
1269 unsigned int notes, loaded, i;
1270 struct module_notes_attrs *notes_attrs;
1271 struct bin_attribute *nattr;
1272
Ingo Molnarea6bff32009-08-28 10:44:56 +02001273 /* failed to create section attributes, so can't create notes */
1274 if (!mod->sect_attrs)
1275 return;
1276
Roland McGrath6d760132007-10-16 23:26:40 -07001277 /* Count notes sections and allocate structures. */
1278 notes = 0;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001279 for (i = 0; i < info->hdr->e_shnum; i++)
1280 if (!sect_empty(&info->sechdrs[i]) &&
1281 (info->sechdrs[i].sh_type == SHT_NOTE))
Roland McGrath6d760132007-10-16 23:26:40 -07001282 ++notes;
1283
1284 if (notes == 0)
1285 return;
1286
1287 notes_attrs = kzalloc(sizeof(*notes_attrs)
1288 + notes * sizeof(notes_attrs->attrs[0]),
1289 GFP_KERNEL);
1290 if (notes_attrs == NULL)
1291 return;
1292
1293 notes_attrs->notes = notes;
1294 nattr = &notes_attrs->attrs[0];
Rusty Russell8f6d0372010-08-05 12:59:09 -06001295 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1296 if (sect_empty(&info->sechdrs[i]))
Roland McGrath6d760132007-10-16 23:26:40 -07001297 continue;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001298 if (info->sechdrs[i].sh_type == SHT_NOTE) {
Eric W. Biederman361795b2010-02-12 13:41:56 -08001299 sysfs_bin_attr_init(nattr);
Roland McGrath6d760132007-10-16 23:26:40 -07001300 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1301 nattr->attr.mode = S_IRUGO;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001302 nattr->size = info->sechdrs[i].sh_size;
1303 nattr->private = (void *) info->sechdrs[i].sh_addr;
Roland McGrath6d760132007-10-16 23:26:40 -07001304 nattr->read = module_notes_read;
1305 ++nattr;
1306 }
1307 ++loaded;
1308 }
1309
Greg Kroah-Hartman4ff6abf2007-11-05 22:24:43 -08001310 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
Roland McGrath6d760132007-10-16 23:26:40 -07001311 if (!notes_attrs->dir)
1312 goto out;
1313
1314 for (i = 0; i < notes; ++i)
1315 if (sysfs_create_bin_file(notes_attrs->dir,
1316 &notes_attrs->attrs[i]))
1317 goto out;
1318
1319 mod->notes_attrs = notes_attrs;
1320 return;
1321
1322 out:
1323 free_notes_attrs(notes_attrs, i);
1324}
1325
1326static void remove_notes_attrs(struct module *mod)
1327{
1328 if (mod->notes_attrs)
1329 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1330}
1331
Linus Torvalds1da177e2005-04-16 15:20:36 -07001332#else
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001333
Rusty Russell8f6d0372010-08-05 12:59:09 -06001334static inline void add_sect_attrs(struct module *mod,
1335 const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001336{
1337}
1338
1339static inline void remove_sect_attrs(struct module *mod)
1340{
1341}
Roland McGrath6d760132007-10-16 23:26:40 -07001342
Rusty Russell8f6d0372010-08-05 12:59:09 -06001343static inline void add_notes_attrs(struct module *mod,
1344 const struct load_info *info)
Roland McGrath6d760132007-10-16 23:26:40 -07001345{
1346}
1347
1348static inline void remove_notes_attrs(struct module *mod)
1349{
1350}
Rusty Russell8f6d0372010-08-05 12:59:09 -06001351#endif /* CONFIG_KALLSYMS */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001352
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001353static void add_usage_links(struct module *mod)
1354{
1355#ifdef CONFIG_MODULE_UNLOAD
1356 struct module_use *use;
1357 int nowarn;
1358
Rusty Russell75676502010-06-05 11:17:36 -06001359 mutex_lock(&module_mutex);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001360 list_for_each_entry(use, &mod->target_list, target_list) {
1361 nowarn = sysfs_create_link(use->target->holders_dir,
1362 &mod->mkobj.kobj, mod->name);
1363 }
Rusty Russell75676502010-06-05 11:17:36 -06001364 mutex_unlock(&module_mutex);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001365#endif
1366}
1367
1368static void del_usage_links(struct module *mod)
1369{
1370#ifdef CONFIG_MODULE_UNLOAD
1371 struct module_use *use;
1372
Rusty Russell75676502010-06-05 11:17:36 -06001373 mutex_lock(&module_mutex);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001374 list_for_each_entry(use, &mod->target_list, target_list)
1375 sysfs_remove_link(use->target->holders_dir, mod->name);
Rusty Russell75676502010-06-05 11:17:36 -06001376 mutex_unlock(&module_mutex);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001377#endif
1378}
1379
Rusty Russell6407ebb22010-06-05 11:17:36 -06001380static int module_add_modinfo_attrs(struct module *mod)
Matt Domschc988d2b2005-06-23 22:05:15 -07001381{
1382 struct module_attribute *attr;
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001383 struct module_attribute *temp_attr;
Matt Domschc988d2b2005-06-23 22:05:15 -07001384 int error = 0;
1385 int i;
1386
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001387 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1388 (ARRAY_SIZE(modinfo_attrs) + 1)),
1389 GFP_KERNEL);
1390 if (!mod->modinfo_attrs)
1391 return -ENOMEM;
1392
1393 temp_attr = mod->modinfo_attrs;
Matt Domschc988d2b2005-06-23 22:05:15 -07001394 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
1395 if (!attr->test ||
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001396 (attr->test && attr->test(mod))) {
1397 memcpy(temp_attr, attr, sizeof(*temp_attr));
Eric W. Biederman361795b2010-02-12 13:41:56 -08001398 sysfs_attr_init(&temp_attr->attr);
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001399 error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
1400 ++temp_attr;
1401 }
Matt Domschc988d2b2005-06-23 22:05:15 -07001402 }
1403 return error;
1404}
1405
Rusty Russell6407ebb22010-06-05 11:17:36 -06001406static void module_remove_modinfo_attrs(struct module *mod)
Matt Domschc988d2b2005-06-23 22:05:15 -07001407{
1408 struct module_attribute *attr;
1409 int i;
1410
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001411 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1412 /* pick a field to test for end of list */
1413 if (!attr->attr.name)
1414 break;
Matt Domschc988d2b2005-06-23 22:05:15 -07001415 sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001416 if (attr->free)
1417 attr->free(mod);
Matt Domschc988d2b2005-06-23 22:05:15 -07001418 }
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001419 kfree(mod->modinfo_attrs);
Matt Domschc988d2b2005-06-23 22:05:15 -07001420}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001421
Rusty Russell6407ebb22010-06-05 11:17:36 -06001422static int mod_sysfs_init(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001423{
1424 int err;
Greg Kroah-Hartman6494a932008-01-27 15:38:40 -08001425 struct kobject *kobj;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001426
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -07001427 if (!module_sysfs_initialized) {
1428 printk(KERN_ERR "%s: module sysfs not initialized\n",
Ed Swierk1cc5f712006-09-25 16:25:36 -07001429 mod->name);
1430 err = -EINVAL;
1431 goto out;
1432 }
Greg Kroah-Hartman6494a932008-01-27 15:38:40 -08001433
1434 kobj = kset_find_obj(module_kset, mod->name);
1435 if (kobj) {
1436 printk(KERN_ERR "%s: module is already loaded\n", mod->name);
1437 kobject_put(kobj);
1438 err = -EINVAL;
1439 goto out;
1440 }
1441
Linus Torvalds1da177e2005-04-16 15:20:36 -07001442 mod->mkobj.mod = mod;
Kay Sieverse17e0f52006-11-24 12:15:25 +01001443
Greg Kroah-Hartmanac3c8142007-12-17 23:05:35 -07001444 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1445 mod->mkobj.kobj.kset = module_kset;
1446 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1447 "%s", mod->name);
1448 if (err)
1449 kobject_put(&mod->mkobj.kobj);
Kay Sievers270a6c42007-01-18 13:26:15 +01001450
Kay Sievers97c146ef2007-11-29 23:46:11 +01001451 /* delay uevent until full sysfs population */
Kay Sievers270a6c42007-01-18 13:26:15 +01001452out:
1453 return err;
1454}
1455
Rusty Russell6407ebb22010-06-05 11:17:36 -06001456static int mod_sysfs_setup(struct module *mod,
Rusty Russell8f6d0372010-08-05 12:59:09 -06001457 const struct load_info *info,
Kay Sievers270a6c42007-01-18 13:26:15 +01001458 struct kernel_param *kparam,
1459 unsigned int num_params)
1460{
1461 int err;
1462
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001463 err = mod_sysfs_init(mod);
1464 if (err)
1465 goto out;
1466
Greg Kroah-Hartman4ff6abf2007-11-05 22:24:43 -08001467 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
Akinobu Mita240936e2007-04-26 00:12:09 -07001468 if (!mod->holders_dir) {
1469 err = -ENOMEM;
Kay Sievers270a6c42007-01-18 13:26:15 +01001470 goto out_unreg;
Akinobu Mita240936e2007-04-26 00:12:09 -07001471 }
Kay Sievers270a6c42007-01-18 13:26:15 +01001472
Linus Torvalds1da177e2005-04-16 15:20:36 -07001473 err = module_param_sysfs_setup(mod, kparam, num_params);
1474 if (err)
Kay Sievers270a6c42007-01-18 13:26:15 +01001475 goto out_unreg_holders;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001476
Matt Domschc988d2b2005-06-23 22:05:15 -07001477 err = module_add_modinfo_attrs(mod);
1478 if (err)
Kay Sieverse17e0f52006-11-24 12:15:25 +01001479 goto out_unreg_param;
Matt Domschc988d2b2005-06-23 22:05:15 -07001480
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001481 add_usage_links(mod);
Rusty Russell8f6d0372010-08-05 12:59:09 -06001482 add_sect_attrs(mod, info);
1483 add_notes_attrs(mod, info);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001484
Kay Sieverse17e0f52006-11-24 12:15:25 +01001485 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001486 return 0;
1487
Kay Sieverse17e0f52006-11-24 12:15:25 +01001488out_unreg_param:
1489 module_param_sysfs_remove(mod);
Kay Sievers270a6c42007-01-18 13:26:15 +01001490out_unreg_holders:
Greg Kroah-Hartman78a2d902007-12-20 08:13:05 -08001491 kobject_put(mod->holders_dir);
Kay Sievers270a6c42007-01-18 13:26:15 +01001492out_unreg:
Kay Sieverse17e0f52006-11-24 12:15:25 +01001493 kobject_put(&mod->mkobj.kobj);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001494out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001495 return err;
1496}
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001497
1498static void mod_sysfs_fini(struct module *mod)
1499{
Rusty Russell8f6d0372010-08-05 12:59:09 -06001500 remove_notes_attrs(mod);
1501 remove_sect_attrs(mod);
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001502 kobject_put(&mod->mkobj.kobj);
1503}
1504
Rusty Russell8f6d0372010-08-05 12:59:09 -06001505#else /* !CONFIG_SYSFS */
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001506
Rusty Russell8f6d0372010-08-05 12:59:09 -06001507static int mod_sysfs_setup(struct module *mod,
1508 const struct load_info *info,
Rusty Russell6407ebb22010-06-05 11:17:36 -06001509 struct kernel_param *kparam,
1510 unsigned int num_params)
1511{
1512 return 0;
1513}
1514
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001515static void mod_sysfs_fini(struct module *mod)
1516{
1517}
1518
Rusty Russell36b03602010-08-05 12:59:09 -06001519static void module_remove_modinfo_attrs(struct module *mod)
1520{
1521}
1522
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001523static void del_usage_links(struct module *mod)
1524{
1525}
1526
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001527#endif /* CONFIG_SYSFS */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001528
Rusty Russell36b03602010-08-05 12:59:09 -06001529static void mod_sysfs_teardown(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001530{
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001531 del_usage_links(mod);
Matt Domschc988d2b2005-06-23 22:05:15 -07001532 module_remove_modinfo_attrs(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001533 module_param_sysfs_remove(mod);
Greg Kroah-Hartman78a2d902007-12-20 08:13:05 -08001534 kobject_put(mod->mkobj.drivers_dir);
1535 kobject_put(mod->holders_dir);
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001536 mod_sysfs_fini(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001537}
1538
1539/*
1540 * unlink the module with the whole machine is stopped with interrupts off
1541 * - this defends against kallsyms not taking locks
1542 */
1543static int __unlink_module(void *_mod)
1544{
1545 struct module *mod = _mod;
1546 list_del(&mod->list);
1547 return 0;
1548}
1549
Rusty Russell75676502010-06-05 11:17:36 -06001550/* Free a module, remove from lists, etc. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001551static void free_module(struct module *mod)
1552{
Li Zefan7ead8b82009-08-17 16:56:28 +08001553 trace_module_free(mod);
1554
Linus Torvalds1da177e2005-04-16 15:20:36 -07001555 /* Delete from various lists */
Rusty Russell75676502010-06-05 11:17:36 -06001556 mutex_lock(&module_mutex);
Rusty Russell9b1a4d32008-07-28 12:16:30 -05001557 stop_machine(__unlink_module, mod, NULL);
Rusty Russell75676502010-06-05 11:17:36 -06001558 mutex_unlock(&module_mutex);
Rusty Russell36b03602010-08-05 12:59:09 -06001559 mod_sysfs_teardown(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001560
Jason Baronb82bab4b2010-07-27 13:18:01 -07001561 /* Remove dynamic debug info */
1562 ddebug_remove_module(mod->name);
1563
Linus Torvalds1da177e2005-04-16 15:20:36 -07001564 /* Arch-specific cleanup. */
1565 module_arch_cleanup(mod);
1566
1567 /* Module unload stuff */
1568 module_unload_free(mod);
1569
Rusty Russelle180a6b2009-03-31 13:05:29 -06001570 /* Free any allocated parameters. */
1571 destroy_params(mod->kp, mod->num_kp);
1572
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573 /* This may be NULL, but that's OK */
1574 module_free(mod, mod->module_init);
1575 kfree(mod->args);
Tejun Heo259354d2010-03-10 18:56:10 +09001576 percpu_modfree(mod);
Rusty Russell9f85a4b2010-08-05 12:59:04 -06001577
Ingo Molnarfbb9ce952006-07-03 00:24:50 -07001578 /* Free lock-classes: */
1579 lockdep_free_key_range(mod->module_core, mod->core_size);
1580
Linus Torvalds1da177e2005-04-16 15:20:36 -07001581 /* Finally, free the core (containing the module structure) */
1582 module_free(mod, mod->module_core);
Bernd Schmidteb8cdec2009-09-21 17:03:57 -07001583
1584#ifdef CONFIG_MPU
1585 update_protections(current->mm);
1586#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001587}
1588
1589void *__symbol_get(const char *symbol)
1590{
1591 struct module *owner;
Tim Abbott414fd312008-12-05 19:03:56 -05001592 const struct kernel_symbol *sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001593
Rusty Russell24da1cb2007-07-15 23:41:46 -07001594 preempt_disable();
Tim Abbott414fd312008-12-05 19:03:56 -05001595 sym = find_symbol(symbol, &owner, NULL, true, true);
1596 if (sym && strong_try_module_get(owner))
1597 sym = NULL;
Rusty Russell24da1cb2007-07-15 23:41:46 -07001598 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001599
Tim Abbott414fd312008-12-05 19:03:56 -05001600 return sym ? (void *)sym->value : NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001601}
1602EXPORT_SYMBOL_GPL(__symbol_get);
1603
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001604/*
1605 * Ensure that an exported symbol [global namespace] does not already exist
Robert P. J. Day02a3e592007-05-09 07:26:28 +02001606 * in the kernel or in some other module's exported symbol table.
Rusty Russellbe593f42010-06-05 11:17:37 -06001607 *
1608 * You must hold the module_mutex.
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001609 */
1610static int verify_export_symbols(struct module *mod)
1611{
Rusty Russellb2111042008-05-01 21:15:00 -05001612 unsigned int i;
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001613 struct module *owner;
Rusty Russellb2111042008-05-01 21:15:00 -05001614 const struct kernel_symbol *s;
1615 struct {
1616 const struct kernel_symbol *sym;
1617 unsigned int num;
1618 } arr[] = {
1619 { mod->syms, mod->num_syms },
1620 { mod->gpl_syms, mod->num_gpl_syms },
1621 { mod->gpl_future_syms, mod->num_gpl_future_syms },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001622#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russellb2111042008-05-01 21:15:00 -05001623 { mod->unused_syms, mod->num_unused_syms },
1624 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05001625#endif
Rusty Russellb2111042008-05-01 21:15:00 -05001626 };
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001627
Rusty Russellb2111042008-05-01 21:15:00 -05001628 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1629 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
Rusty Russellbe593f42010-06-05 11:17:37 -06001630 if (find_symbol(s->name, &owner, NULL, true, false)) {
Rusty Russellb2111042008-05-01 21:15:00 -05001631 printk(KERN_ERR
1632 "%s: exports duplicate symbol %s"
1633 " (owned by %s)\n",
1634 mod->name, s->name, module_name(owner));
1635 return -ENOEXEC;
1636 }
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001637 }
Rusty Russellb2111042008-05-01 21:15:00 -05001638 }
1639 return 0;
Ashutosh Naikeea8b542006-01-08 01:04:25 -08001640}
1641
Matti Linnanvuori9a4b9702007-11-08 08:37:38 -08001642/* Change all symbols so that st_value encodes the pointer directly. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001643static int simplify_symbols(Elf_Shdr *sechdrs,
1644 unsigned int symindex,
1645 const char *strtab,
1646 unsigned int versindex,
1647 unsigned int pcpuindex,
1648 struct module *mod)
1649{
1650 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
1651 unsigned long secbase;
1652 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
1653 int ret = 0;
Tim Abbott414fd312008-12-05 19:03:56 -05001654 const struct kernel_symbol *ksym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001655
1656 for (i = 1; i < n; i++) {
1657 switch (sym[i].st_shndx) {
1658 case SHN_COMMON:
1659 /* We compiled with -fno-common. These are not
1660 supposed to happen. */
1661 DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
1662 printk("%s: please compile with -fno-common\n",
1663 mod->name);
1664 ret = -ENOEXEC;
1665 break;
1666
1667 case SHN_ABS:
1668 /* Don't need to do anything */
1669 DEBUGP("Absolute symbol: 0x%08lx\n",
1670 (long)sym[i].st_value);
1671 break;
1672
1673 case SHN_UNDEF:
Rusty Russell9bea7f22010-06-05 11:17:37 -06001674 ksym = resolve_symbol_wait(sechdrs, versindex,
1675 strtab + sym[i].st_name,
1676 mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001677 /* Ok if resolved. */
Rusty Russell9bea7f22010-06-05 11:17:37 -06001678 if (ksym && !IS_ERR(ksym)) {
Tim Abbott414fd312008-12-05 19:03:56 -05001679 sym[i].st_value = ksym->value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001680 break;
Tim Abbott414fd312008-12-05 19:03:56 -05001681 }
1682
Linus Torvalds1da177e2005-04-16 15:20:36 -07001683 /* Ok if weak. */
Rusty Russell9bea7f22010-06-05 11:17:37 -06001684 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685 break;
1686
Rusty Russell9bea7f22010-06-05 11:17:37 -06001687 printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
1688 mod->name, strtab + sym[i].st_name,
1689 PTR_ERR(ksym));
1690 ret = PTR_ERR(ksym) ?: -ENOENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001691 break;
1692
1693 default:
1694 /* Divert to percpu allocation if a percpu var. */
1695 if (sym[i].st_shndx == pcpuindex)
Tejun Heo259354d2010-03-10 18:56:10 +09001696 secbase = (unsigned long)mod_percpu(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001697 else
1698 secbase = sechdrs[sym[i].st_shndx].sh_addr;
1699 sym[i].st_value += secbase;
1700 break;
1701 }
1702 }
1703
1704 return ret;
1705}
1706
Rusty Russell22e268e2010-08-05 12:59:05 -06001707static int apply_relocations(struct module *mod,
1708 Elf_Ehdr *hdr,
1709 Elf_Shdr *sechdrs,
1710 unsigned int symindex,
1711 unsigned int strindex)
1712{
1713 unsigned int i;
1714 int err = 0;
1715
1716 /* Now do relocations. */
1717 for (i = 1; i < hdr->e_shnum; i++) {
1718 const char *strtab = (char *)sechdrs[strindex].sh_addr;
1719 unsigned int info = sechdrs[i].sh_info;
1720
1721 /* Not a valid relocation section? */
1722 if (info >= hdr->e_shnum)
1723 continue;
1724
1725 /* Don't bother with non-allocated sections */
1726 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
1727 continue;
1728
1729 if (sechdrs[i].sh_type == SHT_REL)
1730 err = apply_relocate(sechdrs, strtab, symindex, i, mod);
1731 else if (sechdrs[i].sh_type == SHT_RELA)
1732 err = apply_relocate_add(sechdrs, strtab, symindex, i,
1733 mod);
1734 if (err < 0)
1735 break;
1736 }
1737 return err;
1738}
1739
Helge Deller088af9a2008-12-31 12:31:18 +01001740/* Additional bytes needed by arch in front of individual sections */
1741unsigned int __weak arch_mod_section_prepend(struct module *mod,
1742 unsigned int section)
1743{
1744 /* default implementation just returns zero */
1745 return 0;
1746}
1747
Linus Torvalds1da177e2005-04-16 15:20:36 -07001748/* Update size with this section: return offset. */
Helge Deller088af9a2008-12-31 12:31:18 +01001749static long get_offset(struct module *mod, unsigned int *size,
1750 Elf_Shdr *sechdr, unsigned int section)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001751{
1752 long ret;
1753
Helge Deller088af9a2008-12-31 12:31:18 +01001754 *size += arch_mod_section_prepend(mod, section);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001755 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1756 *size = ret + sechdr->sh_size;
1757 return ret;
1758}
1759
1760/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1761 might -- code, read-only data, read-write data, small data. Tally
1762 sizes, and place the offsets into sh_entsize fields: high bit means it
1763 belongs in init. */
1764static void layout_sections(struct module *mod,
1765 const Elf_Ehdr *hdr,
1766 Elf_Shdr *sechdrs,
1767 const char *secstrings)
1768{
1769 static unsigned long const masks[][2] = {
1770 /* NOTE: all executable code must be the first section
1771 * in this array; otherwise modify the text_size
1772 * finder in the two loops below */
1773 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1774 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1775 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1776 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1777 };
1778 unsigned int m, i;
1779
1780 for (i = 0; i < hdr->e_shnum; i++)
1781 sechdrs[i].sh_entsize = ~0UL;
1782
1783 DEBUGP("Core section allocation order:\n");
1784 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1785 for (i = 0; i < hdr->e_shnum; ++i) {
1786 Elf_Shdr *s = &sechdrs[i];
1787
1788 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1789 || (s->sh_flags & masks[m][1])
1790 || s->sh_entsize != ~0UL
Rusty Russell49502672009-03-31 13:05:36 -06001791 || strstarts(secstrings + s->sh_name, ".init"))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001792 continue;
Helge Deller088af9a2008-12-31 12:31:18 +01001793 s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001794 DEBUGP("\t%s\n", secstrings + s->sh_name);
1795 }
1796 if (m == 0)
1797 mod->core_text_size = mod->core_size;
1798 }
1799
1800 DEBUGP("Init section allocation order:\n");
1801 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1802 for (i = 0; i < hdr->e_shnum; ++i) {
1803 Elf_Shdr *s = &sechdrs[i];
1804
1805 if ((s->sh_flags & masks[m][0]) != masks[m][0]
1806 || (s->sh_flags & masks[m][1])
1807 || s->sh_entsize != ~0UL
Rusty Russell49502672009-03-31 13:05:36 -06001808 || !strstarts(secstrings + s->sh_name, ".init"))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001809 continue;
Helge Deller088af9a2008-12-31 12:31:18 +01001810 s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001811 | INIT_OFFSET_MASK);
1812 DEBUGP("\t%s\n", secstrings + s->sh_name);
1813 }
1814 if (m == 0)
1815 mod->init_text_size = mod->init_size;
1816 }
1817}
1818
Linus Torvalds1da177e2005-04-16 15:20:36 -07001819static void set_license(struct module *mod, const char *license)
1820{
1821 if (!license)
1822 license = "unspecified";
1823
Florin Malitafa3ba2e82006-10-11 01:21:48 -07001824 if (!license_is_gpl_compatible(license)) {
Andi Kleen25ddbb12008-10-15 22:01:41 -07001825 if (!test_taint(TAINT_PROPRIETARY_MODULE))
Jan Dittmer1d4d2622006-10-28 10:38:38 -07001826 printk(KERN_WARNING "%s: module license '%s' taints "
Florin Malitafa3ba2e82006-10-11 01:21:48 -07001827 "kernel.\n", mod->name, license);
1828 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001829 }
1830}
1831
1832/* Parse tag=value strings from .modinfo section */
1833static char *next_string(char *string, unsigned long *secsize)
1834{
1835 /* Skip non-zero chars */
1836 while (string[0]) {
1837 string++;
1838 if ((*secsize)-- <= 1)
1839 return NULL;
1840 }
1841
1842 /* Skip any zero padding. */
1843 while (!string[0]) {
1844 string++;
1845 if ((*secsize)-- <= 1)
1846 return NULL;
1847 }
1848 return string;
1849}
1850
Rusty Russell40dd2562010-08-05 12:59:03 -06001851static char *get_modinfo(const Elf_Shdr *sechdrs,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001852 unsigned int info,
1853 const char *tag)
1854{
1855 char *p;
1856 unsigned int taglen = strlen(tag);
1857 unsigned long size = sechdrs[info].sh_size;
1858
1859 for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
1860 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1861 return p + taglen + 1;
1862 }
1863 return NULL;
1864}
1865
Matt Domschc988d2b2005-06-23 22:05:15 -07001866static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
1867 unsigned int infoindex)
1868{
1869 struct module_attribute *attr;
1870 int i;
1871
1872 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1873 if (attr->setup)
1874 attr->setup(mod,
1875 get_modinfo(sechdrs,
1876 infoindex,
1877 attr->attr.name));
1878 }
1879}
Matt Domschc988d2b2005-06-23 22:05:15 -07001880
Rusty Russella263f7762009-09-25 00:32:58 -06001881static void free_modinfo(struct module *mod)
1882{
1883 struct module_attribute *attr;
1884 int i;
1885
1886 for (i = 0; (attr = modinfo_attrs[i]); i++) {
1887 if (attr->free)
1888 attr->free(mod);
1889 }
1890}
1891
Linus Torvalds1da177e2005-04-16 15:20:36 -07001892#ifdef CONFIG_KALLSYMS
WANG Cong15bba372008-07-24 15:41:48 +01001893
1894/* lookup symbol in given range of kernel_symbols */
1895static const struct kernel_symbol *lookup_symbol(const char *name,
1896 const struct kernel_symbol *start,
1897 const struct kernel_symbol *stop)
1898{
1899 const struct kernel_symbol *ks = start;
1900 for (; ks < stop; ks++)
1901 if (strcmp(ks->name, name) == 0)
1902 return ks;
1903 return NULL;
1904}
1905
Tim Abbottca4787b2009-01-05 08:40:10 -06001906static int is_exported(const char *name, unsigned long value,
1907 const struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001908{
Tim Abbottca4787b2009-01-05 08:40:10 -06001909 const struct kernel_symbol *ks;
1910 if (!mod)
1911 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
Sam Ravnborg3fd68052006-02-08 21:16:45 +01001912 else
Tim Abbottca4787b2009-01-05 08:40:10 -06001913 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
1914 return ks != NULL && ks->value == value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001915}
1916
1917/* As per nm */
Rusty Russelleded41c2010-08-05 12:59:07 -06001918static char elf_type(const Elf_Sym *sym, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001919{
Rusty Russelleded41c2010-08-05 12:59:07 -06001920 const Elf_Shdr *sechdrs = info->sechdrs;
1921
Linus Torvalds1da177e2005-04-16 15:20:36 -07001922 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
1923 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
1924 return 'v';
1925 else
1926 return 'w';
1927 }
1928 if (sym->st_shndx == SHN_UNDEF)
1929 return 'U';
1930 if (sym->st_shndx == SHN_ABS)
1931 return 'a';
1932 if (sym->st_shndx >= SHN_LORESERVE)
1933 return '?';
1934 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
1935 return 't';
1936 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
1937 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
1938 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
1939 return 'r';
1940 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1941 return 'g';
1942 else
1943 return 'd';
1944 }
1945 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1946 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
1947 return 's';
1948 else
1949 return 'b';
1950 }
Rusty Russelleded41c2010-08-05 12:59:07 -06001951 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
1952 ".debug")) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001953 return 'n';
Rusty Russelleded41c2010-08-05 12:59:07 -06001954 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001955 return '?';
1956}
1957
Jan Beulich4a496222009-07-06 14:50:42 +01001958static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
1959 unsigned int shnum)
1960{
1961 const Elf_Shdr *sec;
1962
1963 if (src->st_shndx == SHN_UNDEF
1964 || src->st_shndx >= shnum
1965 || !src->st_name)
1966 return false;
1967
1968 sec = sechdrs + src->st_shndx;
1969 if (!(sec->sh_flags & SHF_ALLOC)
1970#ifndef CONFIG_KALLSYMS_ALL
1971 || !(sec->sh_flags & SHF_EXECINSTR)
1972#endif
1973 || (sec->sh_entsize & INIT_OFFSET_MASK))
1974 return false;
1975
1976 return true;
1977}
1978
1979static unsigned long layout_symtab(struct module *mod,
1980 Elf_Shdr *sechdrs,
1981 unsigned int symindex,
Jan Beulich554bdfe2009-07-06 14:51:44 +01001982 unsigned int strindex,
Jan Beulich4a496222009-07-06 14:50:42 +01001983 const Elf_Ehdr *hdr,
Jan Beulich554bdfe2009-07-06 14:51:44 +01001984 const char *secstrings,
1985 unsigned long *pstroffs,
1986 unsigned long *strmap)
Jan Beulich4a496222009-07-06 14:50:42 +01001987{
1988 unsigned long symoffs;
1989 Elf_Shdr *symsect = sechdrs + symindex;
Jan Beulich554bdfe2009-07-06 14:51:44 +01001990 Elf_Shdr *strsect = sechdrs + strindex;
Jan Beulich4a496222009-07-06 14:50:42 +01001991 const Elf_Sym *src;
Jan Beulich554bdfe2009-07-06 14:51:44 +01001992 const char *strtab;
Jan Beulich4a496222009-07-06 14:50:42 +01001993 unsigned int i, nsrc, ndst;
1994
1995 /* Put symbol section at end of init part of module. */
1996 symsect->sh_flags |= SHF_ALLOC;
1997 symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
1998 symindex) | INIT_OFFSET_MASK;
1999 DEBUGP("\t%s\n", secstrings + symsect->sh_name);
2000
2001 src = (void *)hdr + symsect->sh_offset;
2002 nsrc = symsect->sh_size / sizeof(*src);
Jan Beulich554bdfe2009-07-06 14:51:44 +01002003 strtab = (void *)hdr + strsect->sh_offset;
Jan Beulich4a496222009-07-06 14:50:42 +01002004 for (ndst = i = 1; i < nsrc; ++i, ++src)
Jan Beulich554bdfe2009-07-06 14:51:44 +01002005 if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
2006 unsigned int j = src->st_name;
2007
2008 while(!__test_and_set_bit(j, strmap) && strtab[j])
2009 ++j;
Jan Beulich4a496222009-07-06 14:50:42 +01002010 ++ndst;
Jan Beulich554bdfe2009-07-06 14:51:44 +01002011 }
Jan Beulich4a496222009-07-06 14:50:42 +01002012
2013 /* Append room for core symbols at end of core part. */
2014 symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
2015 mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
2016
Jan Beulich554bdfe2009-07-06 14:51:44 +01002017 /* Put string table section at end of init part of module. */
2018 strsect->sh_flags |= SHF_ALLOC;
2019 strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
2020 strindex) | INIT_OFFSET_MASK;
2021 DEBUGP("\t%s\n", secstrings + strsect->sh_name);
2022
2023 /* Append room for core symbols' strings at end of core part. */
2024 *pstroffs = mod->core_size;
2025 __set_bit(0, strmap);
2026 mod->core_size += bitmap_weight(strmap, strsect->sh_size);
2027
Jan Beulich4a496222009-07-06 14:50:42 +01002028 return symoffs;
2029}
2030
Rusty Russelld9131882010-08-05 12:59:08 -06002031static void add_kallsyms(struct module *mod, struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002032{
Jan Beulich4a496222009-07-06 14:50:42 +01002033 unsigned int i, ndst;
2034 const Elf_Sym *src;
2035 Elf_Sym *dst;
Jan Beulich554bdfe2009-07-06 14:51:44 +01002036 char *s;
Rusty Russelleded41c2010-08-05 12:59:07 -06002037 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002038
Rusty Russelleded41c2010-08-05 12:59:07 -06002039 mod->symtab = (void *)symsec->sh_addr;
2040 mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
Rusty Russell511ca6a2010-08-05 12:59:08 -06002041 /* Make sure we get permanent strtab: don't use info->strtab. */
2042 mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002043
2044 /* Set types up while we still have access to sections. */
2045 for (i = 0; i < mod->num_symtab; i++)
Rusty Russelleded41c2010-08-05 12:59:07 -06002046 mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
Jan Beulich4a496222009-07-06 14:50:42 +01002047
Rusty Russelld9131882010-08-05 12:59:08 -06002048 mod->core_symtab = dst = mod->module_core + info->symoffs;
Jan Beulich4a496222009-07-06 14:50:42 +01002049 src = mod->symtab;
2050 *dst = *src;
2051 for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
Rusty Russelleded41c2010-08-05 12:59:07 -06002052 if (!is_core_symbol(src, info->sechdrs, info->hdr->e_shnum))
Jan Beulich4a496222009-07-06 14:50:42 +01002053 continue;
2054 dst[ndst] = *src;
Rusty Russelld9131882010-08-05 12:59:08 -06002055 dst[ndst].st_name = bitmap_weight(info->strmap,
2056 dst[ndst].st_name);
Jan Beulich4a496222009-07-06 14:50:42 +01002057 ++ndst;
2058 }
2059 mod->core_num_syms = ndst;
Jan Beulich554bdfe2009-07-06 14:51:44 +01002060
Rusty Russelld9131882010-08-05 12:59:08 -06002061 mod->core_strtab = s = mod->module_core + info->stroffs;
Rusty Russelleded41c2010-08-05 12:59:07 -06002062 for (*s = 0, i = 1; i < info->sechdrs[info->index.str].sh_size; ++i)
Rusty Russelld9131882010-08-05 12:59:08 -06002063 if (test_bit(i, info->strmap))
Jan Beulich554bdfe2009-07-06 14:51:44 +01002064 *++s = mod->strtab[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002065}
2066#else
Jan Beulich4a496222009-07-06 14:50:42 +01002067static inline unsigned long layout_symtab(struct module *mod,
2068 Elf_Shdr *sechdrs,
2069 unsigned int symindex,
Jan Beulich554bdfe2009-07-06 14:51:44 +01002070 unsigned int strindex,
Paul Mundt3ae91c22009-10-01 15:43:54 -07002071 const Elf_Ehdr *hdr,
Jan Beulich554bdfe2009-07-06 14:51:44 +01002072 const char *secstrings,
2073 unsigned long *pstroffs,
2074 unsigned long *strmap)
Jan Beulich4a496222009-07-06 14:50:42 +01002075{
Paul Mundt3ae91c22009-10-01 15:43:54 -07002076 return 0;
Jan Beulich4a496222009-07-06 14:50:42 +01002077}
Paul Mundt3ae91c22009-10-01 15:43:54 -07002078
Rusty Russelld9131882010-08-05 12:59:08 -06002079static void add_kallsyms(struct module *mod, struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002080{
2081}
2082#endif /* CONFIG_KALLSYMS */
2083
Jason Barone9d376f2009-02-05 11:51:38 -05002084static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
Rusty Russell5e458cc2008-10-22 10:00:13 -05002085{
Jason Barone9d376f2009-02-05 11:51:38 -05002086#ifdef CONFIG_DYNAMIC_DEBUG
2087 if (ddebug_add_module(debug, num, debug->modname))
2088 printk(KERN_ERR "dynamic debug error adding module: %s\n",
2089 debug->modname);
2090#endif
Rusty Russell5e458cc2008-10-22 10:00:13 -05002091}
Jason Baron346e15b2008-08-12 16:46:19 -04002092
Yehuda Sadehff49d742010-07-03 13:07:35 +10002093static void dynamic_debug_remove(struct _ddebug *debug)
2094{
2095 if (debug)
2096 ddebug_remove_module(debug->modname);
2097}
2098
Rusty Russell3a642e92008-07-22 19:24:28 -05002099static void *module_alloc_update_bounds(unsigned long size)
2100{
2101 void *ret = module_alloc(size);
2102
2103 if (ret) {
Rusty Russell75676502010-06-05 11:17:36 -06002104 mutex_lock(&module_mutex);
Rusty Russell3a642e92008-07-22 19:24:28 -05002105 /* Update module bounds. */
2106 if ((unsigned long)ret < module_addr_min)
2107 module_addr_min = (unsigned long)ret;
2108 if ((unsigned long)ret + size > module_addr_max)
2109 module_addr_max = (unsigned long)ret + size;
Rusty Russell75676502010-06-05 11:17:36 -06002110 mutex_unlock(&module_mutex);
Rusty Russell3a642e92008-07-22 19:24:28 -05002111 }
2112 return ret;
2113}
2114
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002115#ifdef CONFIG_DEBUG_KMEMLEAK
2116static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002117 const Elf_Shdr *sechdrs,
2118 const char *secstrings)
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002119{
2120 unsigned int i;
2121
2122 /* only scan the sections containing data */
Catalin Marinasc017b4b2009-10-28 13:33:09 +00002123 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002124
2125 for (i = 1; i < hdr->e_shnum; i++) {
2126 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2127 continue;
2128 if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
2129 && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
2130 continue;
2131
Catalin Marinasc017b4b2009-10-28 13:33:09 +00002132 kmemleak_scan_area((void *)sechdrs[i].sh_addr,
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002133 sechdrs[i].sh_size, GFP_KERNEL);
2134 }
2135}
2136#else
2137static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002138 Elf_Shdr *sechdrs,
2139 const char *secstrings)
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002140{
2141}
2142#endif
2143
Rusty Russelld9131882010-08-05 12:59:08 -06002144/* Sets info->hdr, info->len and info->args. */
2145static int copy_and_check(struct load_info *info,
2146 const void __user *umod, unsigned long len,
2147 const char __user *uargs)
Rusty Russell40dd2562010-08-05 12:59:03 -06002148{
2149 int err;
2150 Elf_Ehdr *hdr;
2151
2152 if (len < sizeof(*hdr))
2153 return -ENOEXEC;
2154
2155 /* Suck in entire file: we'll want most of it. */
2156 /* vmalloc barfs on "unusual" numbers. Check here */
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002157 if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
Rusty Russell40dd2562010-08-05 12:59:03 -06002158 return -ENOMEM;
2159
2160 if (copy_from_user(hdr, umod, len) != 0) {
2161 err = -EFAULT;
2162 goto free_hdr;
2163 }
2164
2165 /* Sanity checks against insmoding binaries or wrong arch,
2166 weird elf version */
2167 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
2168 || hdr->e_type != ET_REL
2169 || !elf_check_arch(hdr)
2170 || hdr->e_shentsize != sizeof(Elf_Shdr)) {
2171 err = -ENOEXEC;
2172 goto free_hdr;
2173 }
2174
2175 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
2176 err = -ENOEXEC;
2177 goto free_hdr;
2178 }
Rusty Russelld9131882010-08-05 12:59:08 -06002179
2180 /* Now copy in args */
2181 info->args = strndup_user(uargs, ~0UL >> 1);
2182 if (IS_ERR(info->args)) {
2183 err = PTR_ERR(info->args);
2184 goto free_hdr;
2185 }
2186
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002187 info->hdr = hdr;
2188 info->len = len;
Rusty Russell40dd2562010-08-05 12:59:03 -06002189 return 0;
2190
2191free_hdr:
2192 vfree(hdr);
2193 return err;
2194}
2195
Rusty Russelld9131882010-08-05 12:59:08 -06002196static void free_copy(struct load_info *info)
2197{
2198 kfree(info->args);
2199 vfree(info->hdr);
2200}
2201
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002202static int rewrite_section_headers(struct load_info *info)
2203{
2204 unsigned int i;
2205
2206 /* This should always be true, but let's be sure. */
2207 info->sechdrs[0].sh_addr = 0;
2208
2209 for (i = 1; i < info->hdr->e_shnum; i++) {
2210 Elf_Shdr *shdr = &info->sechdrs[i];
2211 if (shdr->sh_type != SHT_NOBITS
2212 && info->len < shdr->sh_offset + shdr->sh_size) {
2213 printk(KERN_ERR "Module len %lu truncated\n",
2214 info->len);
2215 return -ENOEXEC;
2216 }
2217
2218 /* Mark all sections sh_addr with their address in the
2219 temporary image. */
2220 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2221
2222#ifndef CONFIG_MODULE_UNLOAD
2223 /* Don't load .exit sections */
2224 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2225 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2226#endif
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002227 }
Rusty Russelld6df72a2010-08-05 12:59:07 -06002228
2229 /* Track but don't keep modinfo and version sections. */
2230 info->index.vers = find_sec(info->hdr, info->sechdrs, info->secstrings, "__versions");
2231 info->index.info = find_sec(info->hdr, info->sechdrs, info->secstrings, ".modinfo");
2232 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2233 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002234 return 0;
2235}
2236
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002237/*
2238 * Set up our basic convenience variables (pointers to section headers,
2239 * search for module section index etc), and do some basic section
2240 * verification.
2241 *
2242 * Return the temporary module pointer (we'll replace it with the final
2243 * one when we move the module sections around).
2244 */
2245static struct module *setup_load_info(struct load_info *info)
2246{
2247 unsigned int i;
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002248 int err;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002249 struct module *mod;
2250
2251 /* Set up the convenience variables */
2252 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002253 info->secstrings = (void *)info->hdr
2254 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002255
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002256 err = rewrite_section_headers(info);
2257 if (err)
2258 return ERR_PTR(err);
2259
2260 /* Find internal symbols and strings. */
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002261 for (i = 1; i < info->hdr->e_shnum; i++) {
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002262 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2263 info->index.sym = i;
2264 info->index.str = info->sechdrs[i].sh_link;
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002265 info->strtab = (char *)info->hdr
2266 + info->sechdrs[info->index.str].sh_offset;
2267 break;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002268 }
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002269 }
2270
2271 info->index.mod = find_sec(info->hdr, info->sechdrs, info->secstrings,
2272 ".gnu.linkonce.this_module");
2273 if (!info->index.mod) {
2274 printk(KERN_WARNING "No module found in object\n");
2275 return ERR_PTR(-ENOEXEC);
2276 }
2277 /* This is temporary: point mod into copy of data. */
2278 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2279
2280 if (info->index.sym == 0) {
2281 printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
2282 mod->name);
2283 return ERR_PTR(-ENOEXEC);
2284 }
2285
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002286 info->index.pcpu = find_pcpusec(info->hdr, info->sechdrs, info->secstrings);
2287
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002288 /* Check module struct version now, before we try to use module. */
2289 if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
2290 return ERR_PTR(-ENOEXEC);
2291
2292 return mod;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002293}
2294
Rusty Russell40dd2562010-08-05 12:59:03 -06002295static int check_modinfo(struct module *mod,
2296 const Elf_Shdr *sechdrs,
2297 unsigned int infoindex, unsigned int versindex)
2298{
2299 const char *modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
2300 int err;
2301
2302 /* This is allowed: modprobe --force will invalidate it. */
2303 if (!modmagic) {
2304 err = try_to_force_load(mod, "bad vermagic");
2305 if (err)
2306 return err;
2307 } else if (!same_magic(modmagic, vermagic, versindex)) {
2308 printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
2309 mod->name, modmagic, vermagic);
2310 return -ENOEXEC;
2311 }
2312
2313 if (get_modinfo(sechdrs, infoindex, "staging")) {
2314 add_taint_module(mod, TAINT_CRAP);
2315 printk(KERN_WARNING "%s: module is from the staging directory,"
2316 " the quality is unknown, you have been warned.\n",
2317 mod->name);
2318 }
Rusty Russell22e268e2010-08-05 12:59:05 -06002319
2320 /* Set up license info based on the info section */
2321 set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
2322
Rusty Russell40dd2562010-08-05 12:59:03 -06002323 return 0;
2324}
2325
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002326static void find_module_sections(struct module *mod, Elf_Ehdr *hdr,
2327 Elf_Shdr *sechdrs, const char *secstrings)
2328{
2329 mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
2330 sizeof(*mod->kp), &mod->num_kp);
2331 mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
2332 sizeof(*mod->syms), &mod->num_syms);
2333 mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
2334 mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
2335 sizeof(*mod->gpl_syms),
2336 &mod->num_gpl_syms);
2337 mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
2338 mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
2339 "__ksymtab_gpl_future",
2340 sizeof(*mod->gpl_future_syms),
2341 &mod->num_gpl_future_syms);
2342 mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
2343 "__kcrctab_gpl_future");
2344
2345#ifdef CONFIG_UNUSED_SYMBOLS
2346 mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
2347 "__ksymtab_unused",
2348 sizeof(*mod->unused_syms),
2349 &mod->num_unused_syms);
2350 mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
2351 "__kcrctab_unused");
2352 mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
2353 "__ksymtab_unused_gpl",
2354 sizeof(*mod->unused_gpl_syms),
2355 &mod->num_unused_gpl_syms);
2356 mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
2357 "__kcrctab_unused_gpl");
2358#endif
2359#ifdef CONFIG_CONSTRUCTORS
2360 mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
2361 sizeof(*mod->ctors), &mod->num_ctors);
2362#endif
2363
2364#ifdef CONFIG_TRACEPOINTS
2365 mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
2366 "__tracepoints",
2367 sizeof(*mod->tracepoints),
2368 &mod->num_tracepoints);
2369#endif
2370#ifdef CONFIG_EVENT_TRACING
2371 mod->trace_events = section_objs(hdr, sechdrs, secstrings,
2372 "_ftrace_events",
2373 sizeof(*mod->trace_events),
2374 &mod->num_trace_events);
2375 /*
2376 * This section contains pointers to allocated objects in the trace
2377 * code and not scanning it leads to false positives.
2378 */
2379 kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
2380 mod->num_trace_events, GFP_KERNEL);
2381#endif
2382#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2383 /* sechdrs[0].sh_size is always zero */
2384 mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
2385 "__mcount_loc",
2386 sizeof(*mod->ftrace_callsites),
2387 &mod->num_ftrace_callsites);
2388#endif
Rusty Russell22e268e2010-08-05 12:59:05 -06002389
2390 if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
2391 printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
2392 mod->name);
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06002393}
2394
Rusty Russelld9131882010-08-05 12:59:08 -06002395static int move_module(struct module *mod,
2396 Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
2397 const char *secstrings, unsigned modindex)
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002398{
2399 int i;
2400 void *ptr;
2401
2402 /* Do the allocs. */
2403 ptr = module_alloc_update_bounds(mod->core_size);
2404 /*
2405 * The pointer to this block is stored in the module structure
2406 * which is inside the block. Just mark it as not being a
2407 * leak.
2408 */
2409 kmemleak_not_leak(ptr);
2410 if (!ptr)
Rusty Russelld9131882010-08-05 12:59:08 -06002411 return -ENOMEM;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002412
2413 memset(ptr, 0, mod->core_size);
2414 mod->module_core = ptr;
2415
2416 ptr = module_alloc_update_bounds(mod->init_size);
2417 /*
2418 * The pointer to this block is stored in the module structure
2419 * which is inside the block. This block doesn't need to be
2420 * scanned as it contains data and code that will be freed
2421 * after the module is initialized.
2422 */
2423 kmemleak_ignore(ptr);
2424 if (!ptr && mod->init_size) {
2425 module_free(mod, mod->module_core);
Rusty Russelld9131882010-08-05 12:59:08 -06002426 return -ENOMEM;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002427 }
2428 memset(ptr, 0, mod->init_size);
2429 mod->module_init = ptr;
2430
2431 /* Transfer each section which specifies SHF_ALLOC */
2432 DEBUGP("final section addresses:\n");
2433 for (i = 0; i < hdr->e_shnum; i++) {
2434 void *dest;
2435
2436 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
2437 continue;
2438
2439 if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
2440 dest = mod->module_init
2441 + (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
2442 else
2443 dest = mod->module_core + sechdrs[i].sh_entsize;
2444
2445 if (sechdrs[i].sh_type != SHT_NOBITS)
2446 memcpy(dest, (void *)sechdrs[i].sh_addr,
2447 sechdrs[i].sh_size);
2448 /* Update sh_addr to point to copy in image. */
2449 sechdrs[i].sh_addr = (unsigned long)dest;
2450 DEBUGP("\t0x%lx %s\n",
2451 sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
2452 }
Rusty Russelld9131882010-08-05 12:59:08 -06002453
2454 return 0;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06002455}
2456
Rusty Russell22e268e2010-08-05 12:59:05 -06002457static int check_module_license_and_versions(struct module *mod,
2458 Elf_Shdr *sechdrs)
2459{
2460 /*
2461 * ndiswrapper is under GPL by itself, but loads proprietary modules.
2462 * Don't use add_taint_module(), as it would prevent ndiswrapper from
2463 * using GPL-only symbols it needs.
2464 */
2465 if (strcmp(mod->name, "ndiswrapper") == 0)
2466 add_taint(TAINT_PROPRIETARY_MODULE);
2467
2468 /* driverloader was caught wrongly pretending to be under GPL */
2469 if (strcmp(mod->name, "driverloader") == 0)
2470 add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
2471
2472#ifdef CONFIG_MODVERSIONS
2473 if ((mod->num_syms && !mod->crcs)
2474 || (mod->num_gpl_syms && !mod->gpl_crcs)
2475 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
2476#ifdef CONFIG_UNUSED_SYMBOLS
2477 || (mod->num_unused_syms && !mod->unused_crcs)
2478 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
2479#endif
2480 ) {
2481 return try_to_force_load(mod,
2482 "no versions for exported symbols");
2483 }
2484#endif
2485 return 0;
2486}
2487
2488static void flush_module_icache(const struct module *mod)
2489{
2490 mm_segment_t old_fs;
2491
2492 /* flush the icache in correct context */
2493 old_fs = get_fs();
2494 set_fs(KERNEL_DS);
2495
2496 /*
2497 * Flush the instruction cache, since we've played with text.
2498 * Do it before processing of module parameters, so the module
2499 * can provide parameter accessor functions of its own.
2500 */
2501 if (mod->module_init)
2502 flush_icache_range((unsigned long)mod->module_init,
2503 (unsigned long)mod->module_init
2504 + mod->init_size);
2505 flush_icache_range((unsigned long)mod->module_core,
2506 (unsigned long)mod->module_core + mod->core_size);
2507
2508 set_fs(old_fs);
2509}
2510
Rusty Russelld9131882010-08-05 12:59:08 -06002511static struct module *layout_and_allocate(struct load_info *info)
2512{
2513 /* Module within temporary copy. */
2514 struct module *mod;
2515 int err;
2516
2517 mod = setup_load_info(info);
2518 if (IS_ERR(mod))
2519 return mod;
2520
2521 err = check_modinfo(mod, info->sechdrs, info->index.info, info->index.vers);
2522 if (err)
2523 return ERR_PTR(err);
2524
2525 /* Allow arches to frob section contents and sizes. */
2526 err = module_frob_arch_sections(info->hdr, info->sechdrs, info->secstrings, mod);
2527 if (err < 0)
2528 goto free_args;
2529
2530 if (info->index.pcpu) {
2531 /* We have a special allocation for this section. */
2532 err = percpu_modalloc(mod, info->sechdrs[info->index.pcpu].sh_size,
2533 info->sechdrs[info->index.pcpu].sh_addralign);
2534 if (err)
2535 goto free_args;
2536 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
2537 }
2538
2539 /* Determine total sizes, and put offsets in sh_entsize. For now
2540 this is done generically; there doesn't appear to be any
2541 special cases for the architectures. */
2542 layout_sections(mod, info->hdr, info->sechdrs, info->secstrings);
2543
2544 info->strmap = kzalloc(BITS_TO_LONGS(info->sechdrs[info->index.str].sh_size)
2545 * sizeof(long), GFP_KERNEL);
2546 if (!info->strmap) {
2547 err = -ENOMEM;
2548 goto free_percpu;
2549 }
2550 info->symoffs = layout_symtab(mod, info->sechdrs, info->index.sym, info->index.str, info->hdr,
2551 info->secstrings, &info->stroffs, info->strmap);
2552
2553 /* Allocate and move to the final place */
2554 err = move_module(mod, info->hdr, info->sechdrs, info->secstrings, info->index.mod);
2555 if (err)
2556 goto free_strmap;
2557
2558 /* Module has been copied to its final place now: return it. */
2559 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2560 kmemleak_load_module(mod, info->hdr, info->sechdrs, info->secstrings);
2561 return mod;
2562
2563free_strmap:
2564 kfree(info->strmap);
2565free_percpu:
2566 percpu_modfree(mod);
2567free_args:
2568 kfree(info->args);
2569 return ERR_PTR(err);
2570}
2571
2572/* mod is no longer valid after this! */
2573static void module_deallocate(struct module *mod, struct load_info *info)
2574{
2575 kfree(info->strmap);
2576 percpu_modfree(mod);
2577 module_free(mod, mod->module_init);
2578 module_free(mod, mod->module_core);
2579}
2580
Linus Torvalds1da177e2005-04-16 15:20:36 -07002581/* Allocate and load the module: note that size of section 0 is always
2582 zero, and we rely on this for optional sections. */
Linus Torvaldsffb4ba72008-08-25 11:10:26 -07002583static noinline struct module *load_module(void __user *umod,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002584 unsigned long len,
2585 const char __user *uargs)
2586{
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002587 struct load_info info = { NULL, };
Linus Torvalds1da177e2005-04-16 15:20:36 -07002588 struct module *mod;
Rusty Russell40dd2562010-08-05 12:59:03 -06002589 long err;
Yehuda Sadehff49d742010-07-03 13:07:35 +10002590 struct _ddebug *debug = NULL;
2591 unsigned int num_debug = 0;
Paul Mundt3ae91c22009-10-01 15:43:54 -07002592
Linus Torvalds1da177e2005-04-16 15:20:36 -07002593 DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
2594 umod, len, uargs);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002595
Rusty Russelld9131882010-08-05 12:59:08 -06002596 /* Copy in the blobs from userspace, check they are vaguely sane. */
2597 err = copy_and_check(&info, umod, len, uargs);
Rusty Russell40dd2562010-08-05 12:59:03 -06002598 if (err)
2599 return ERR_PTR(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002600
Rusty Russelld9131882010-08-05 12:59:08 -06002601 /* Figure out module layout, and allocate all the memory. */
2602 mod = layout_and_allocate(&info);
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002603 if (IS_ERR(mod)) {
2604 err = PTR_ERR(mod);
Rusty Russelld9131882010-08-05 12:59:08 -06002605 goto free_copy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002606 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002607
2608 /* Now we've moved module, initialize linked lists, etc. */
Rusty Russell9f85a4b2010-08-05 12:59:04 -06002609 err = module_unload_init(mod);
2610 if (err)
Rusty Russelld9131882010-08-05 12:59:08 -06002611 goto free_module;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002612
Rusty Russell22e268e2010-08-05 12:59:05 -06002613 /* Now we've got everything in the final locations, we can
2614 * find optional sections. */
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002615 find_module_sections(mod, info.hdr, info.sechdrs, info.secstrings);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002616
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002617 err = check_module_license_and_versions(mod, info.sechdrs);
Rusty Russell22e268e2010-08-05 12:59:05 -06002618 if (err)
2619 goto free_unload;
Dave Jones9841d612006-01-08 01:03:41 -08002620
Matt Domschc988d2b2005-06-23 22:05:15 -07002621 /* Set up MODINFO_ATTR fields */
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002622 setup_modinfo(mod, info.sechdrs, info.index.info);
Matt Domschc988d2b2005-06-23 22:05:15 -07002623
Linus Torvalds1da177e2005-04-16 15:20:36 -07002624 /* Fix up syms, so that st_value is a pointer to location. */
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002625 err = simplify_symbols(info.sechdrs, info.index.sym, info.strtab, info.index.vers, info.index.pcpu,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002626 mod);
2627 if (err < 0)
Rusty Russelld9131882010-08-05 12:59:08 -06002628 goto free_modinfo;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002629
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002630 err = apply_relocations(mod, info.hdr, info.sechdrs, info.index.sym, info.index.str);
Rusty Russell22e268e2010-08-05 12:59:05 -06002631 if (err < 0)
Rusty Russelld9131882010-08-05 12:59:08 -06002632 goto free_modinfo;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002633
2634 /* Set up and sort exception table */
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002635 mod->extable = section_objs(info.hdr, info.sechdrs, info.secstrings, "__ex_table",
Rusty Russell5e458cc2008-10-22 10:00:13 -05002636 sizeof(*mod->extable), &mod->num_exentries);
2637 sort_extable(mod->extable, mod->extable + mod->num_exentries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002638
2639 /* Finally, copy percpu area over. */
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002640 percpu_modcopy(mod, (void *)info.sechdrs[info.index.pcpu].sh_addr,
2641 info.sechdrs[info.index.pcpu].sh_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002642
Rusty Russelld9131882010-08-05 12:59:08 -06002643 add_kallsyms(mod, &info);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002644
Yehuda Sadehff49d742010-07-03 13:07:35 +10002645 if (!mod->taints)
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002646 debug = section_objs(info.hdr, info.sechdrs, info.secstrings, "__verbose",
Rusty Russell5e458cc2008-10-22 10:00:13 -05002647 sizeof(*debug), &num_debug);
Steven Rostedt90d595f2008-08-14 15:45:09 -04002648
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002649 err = module_finalize(info.hdr, info.sechdrs, mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002650 if (err < 0)
Rusty Russelld9131882010-08-05 12:59:08 -06002651 goto free_modinfo;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002652
Rusty Russell22e268e2010-08-05 12:59:05 -06002653 flush_module_icache(mod);
Thomas Koeller378bac82005-09-06 15:17:11 -07002654
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002655 mod->args = info.args;
Rusty Russell8d3b33f2006-03-25 03:07:05 -08002656
Rusty Russelld9131882010-08-05 12:59:08 -06002657 mod->state = MODULE_STATE_COMING;
2658
Rusty Russellbb9d3d52008-01-29 17:13:21 -05002659 /* Now sew it into the lists so we can get lockdep and oops
Andi Kleend72b3752008-08-30 10:09:00 +02002660 * info during argument parsing. Noone should access us, since
2661 * strong_try_module_get() will fail.
2662 * lockdep/oops can run asynchronous, so use the RCU list insertion
2663 * function to insert in a way safe to concurrent readers.
2664 * The mutex protects against concurrent writers.
2665 */
Rusty Russell75676502010-06-05 11:17:36 -06002666 mutex_lock(&module_mutex);
Linus Torvalds3bafeb62010-06-05 11:17:36 -06002667 if (find_module(mod->name)) {
2668 err = -EEXIST;
Rusty Russellbe593f42010-06-05 11:17:37 -06002669 goto unlock;
Linus Torvalds3bafeb62010-06-05 11:17:36 -06002670 }
2671
Yehuda Sadehff49d742010-07-03 13:07:35 +10002672 if (debug)
2673 dynamic_debug_setup(debug, num_debug);
2674
Rusty Russellbe593f42010-06-05 11:17:37 -06002675 /* Find duplicate symbols */
2676 err = verify_export_symbols(mod);
2677 if (err < 0)
Yehuda Sadehff49d742010-07-03 13:07:35 +10002678 goto ddebug;
Rusty Russellbe593f42010-06-05 11:17:37 -06002679
Andi Kleend72b3752008-08-30 10:09:00 +02002680 list_add_rcu(&mod->list, &modules);
Rusty Russell75676502010-06-05 11:17:36 -06002681 mutex_unlock(&module_mutex);
Rusty Russellbb9d3d52008-01-29 17:13:21 -05002682
Rusty Russelle180a6b2009-03-31 13:05:29 -06002683 err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002684 if (err < 0)
Rusty Russellbb9d3d52008-01-29 17:13:21 -05002685 goto unlink;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002686
Rusty Russell8f6d0372010-08-05 12:59:09 -06002687 err = mod_sysfs_setup(mod, &info, mod->kp, mod->num_kp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002688 if (err < 0)
Rusty Russellbb9d3d52008-01-29 17:13:21 -05002689 goto unlink;
Rusty Russell80a3d1b2010-06-05 11:17:36 -06002690
Rusty Russelld9131882010-08-05 12:59:08 -06002691 /* Get rid of temporary copy and strmap. */
2692 kfree(info.strmap);
2693 free_copy(&info);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002694
Li Zefan7ead8b82009-08-17 16:56:28 +08002695 trace_module_load(mod);
2696
Linus Torvalds1da177e2005-04-16 15:20:36 -07002697 /* Done! */
2698 return mod;
2699
Rusty Russellbb9d3d52008-01-29 17:13:21 -05002700 unlink:
Rusty Russell75676502010-06-05 11:17:36 -06002701 mutex_lock(&module_mutex);
Rusty Russelle91defa2009-03-31 13:05:35 -06002702 /* Unlink carefully: kallsyms could be walking list. */
2703 list_del_rcu(&mod->list);
Yehuda Sadehff49d742010-07-03 13:07:35 +10002704 ddebug:
2705 dynamic_debug_remove(debug);
Rusty Russellbe593f42010-06-05 11:17:37 -06002706 unlock:
Rusty Russell75676502010-06-05 11:17:36 -06002707 mutex_unlock(&module_mutex);
Rusty Russelle91defa2009-03-31 13:05:35 -06002708 synchronize_sched();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002709 module_arch_cleanup(mod);
Rusty Russelld9131882010-08-05 12:59:08 -06002710 free_modinfo:
Rusty Russella263f7762009-09-25 00:32:58 -06002711 free_modinfo(mod);
Rusty Russell22e268e2010-08-05 12:59:05 -06002712 free_unload:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002713 module_unload_free(mod);
Rusty Russelld9131882010-08-05 12:59:08 -06002714 free_module:
2715 module_deallocate(mod, &info);
2716 free_copy:
2717 free_copy(&info);
Jayachandran C6fe2e702006-01-06 00:19:54 -08002718 return ERR_PTR(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002719}
2720
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -07002721/* Call module constructors. */
2722static void do_mod_ctors(struct module *mod)
2723{
2724#ifdef CONFIG_CONSTRUCTORS
2725 unsigned long i;
2726
2727 for (i = 0; i < mod->num_ctors; i++)
2728 mod->ctors[i]();
2729#endif
2730}
2731
Linus Torvalds1da177e2005-04-16 15:20:36 -07002732/* This is where the real work happens */
Heiko Carstens17da2bd2009-01-14 14:14:10 +01002733SYSCALL_DEFINE3(init_module, void __user *, umod,
2734 unsigned long, len, const char __user *, uargs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002735{
2736 struct module *mod;
2737 int ret = 0;
2738
2739 /* Must have permission */
Kees Cook3d433212009-04-02 15:49:29 -07002740 if (!capable(CAP_SYS_MODULE) || modules_disabled)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002741 return -EPERM;
2742
Linus Torvalds1da177e2005-04-16 15:20:36 -07002743 /* Do all the hard work */
2744 mod = load_module(umod, len, uargs);
Rusty Russell75676502010-06-05 11:17:36 -06002745 if (IS_ERR(mod))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002746 return PTR_ERR(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002747
Alan Sterne041c682006-03-27 01:16:30 -08002748 blocking_notifier_call_chain(&module_notify_list,
2749 MODULE_STATE_COMING, mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002750
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -07002751 do_mod_ctors(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002752 /* Start the module */
2753 if (mod->init != NULL)
Arjan van de Ven59f94152008-07-30 12:49:02 -07002754 ret = do_one_initcall(mod->init);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002755 if (ret < 0) {
2756 /* Init routine failed: abort. Try to protect us from
2757 buggy refcounters. */
2758 mod->state = MODULE_STATE_GOING;
Paul E. McKenneyfbd568a3e2005-05-01 08:59:04 -07002759 synchronize_sched();
Rusty Russellaf49d922007-10-16 23:26:27 -07002760 module_put(mod);
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +02002761 blocking_notifier_call_chain(&module_notify_list,
2762 MODULE_STATE_GOING, mod);
Rusty Russellaf49d922007-10-16 23:26:27 -07002763 free_module(mod);
Rusty Russellc9a3ba52008-01-29 17:13:18 -05002764 wake_up(&module_wq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002765 return ret;
2766 }
Alexey Dobriyane24e2e62008-03-10 11:43:53 -07002767 if (ret > 0) {
Joe Perchesad361c92009-07-06 13:05:40 -07002768 printk(KERN_WARNING
2769"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
2770"%s: loading module anyway...\n",
Alexey Dobriyane24e2e62008-03-10 11:43:53 -07002771 __func__, mod->name, ret,
2772 __func__);
2773 dump_stack();
2774 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002775
Rusty Russell6c5db222008-03-10 11:43:52 -07002776 /* Now it's a first class citizen! Wake up anyone waiting for it. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002777 mod->state = MODULE_STATE_LIVE;
Rusty Russell6c5db222008-03-10 11:43:52 -07002778 wake_up(&module_wq);
Masami Hiramatsu0deddf42009-01-06 14:41:54 -08002779 blocking_notifier_call_chain(&module_notify_list,
2780 MODULE_STATE_LIVE, mod);
Rusty Russell6c5db222008-03-10 11:43:52 -07002781
Linus Torvaldsd6de2c82009-04-10 12:17:41 -07002782 /* We need to finish all async code before the module init sequence is done */
2783 async_synchronize_full();
2784
Rusty Russell6c5db222008-03-10 11:43:52 -07002785 mutex_lock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002786 /* Drop initial reference. */
2787 module_put(mod);
Rusty Russellad6561d2009-06-12 21:47:03 -06002788 trim_init_extable(mod);
Jan Beulich4a496222009-07-06 14:50:42 +01002789#ifdef CONFIG_KALLSYMS
2790 mod->num_symtab = mod->core_num_syms;
2791 mod->symtab = mod->core_symtab;
Jan Beulich554bdfe2009-07-06 14:51:44 +01002792 mod->strtab = mod->core_strtab;
Jan Beulich4a496222009-07-06 14:50:42 +01002793#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002794 module_free(mod, mod->module_init);
2795 mod->module_init = NULL;
2796 mod->init_size = 0;
2797 mod->init_text_size = 0;
Ashutosh Naik6389a382006-03-23 03:00:46 -08002798 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002799
2800 return 0;
2801}
2802
2803static inline int within(unsigned long addr, void *start, unsigned long size)
2804{
2805 return ((void *)addr >= start && (void *)addr < start + size);
2806}
2807
2808#ifdef CONFIG_KALLSYMS
2809/*
2810 * This ignores the intensely annoying "mapping symbols" found
2811 * in ARM ELF files: $a, $t and $d.
2812 */
2813static inline int is_arm_mapping_symbol(const char *str)
2814{
Daniel Walker22a8bde2007-10-18 03:06:07 -07002815 return str[0] == '$' && strchr("atd", str[1])
Linus Torvalds1da177e2005-04-16 15:20:36 -07002816 && (str[2] == '\0' || str[2] == '.');
2817}
2818
2819static const char *get_ksymbol(struct module *mod,
2820 unsigned long addr,
2821 unsigned long *size,
2822 unsigned long *offset)
2823{
2824 unsigned int i, best = 0;
2825 unsigned long nextval;
2826
2827 /* At worse, next value is at end of module */
Masami Hiramatsua06f6212009-01-06 14:41:49 -08002828 if (within_module_init(addr, mod))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002829 nextval = (unsigned long)mod->module_init+mod->init_text_size;
Daniel Walker22a8bde2007-10-18 03:06:07 -07002830 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07002831 nextval = (unsigned long)mod->module_core+mod->core_text_size;
2832
2833 /* Scan for closest preceeding symbol, and next symbol. (ELF
Daniel Walker22a8bde2007-10-18 03:06:07 -07002834 starts real symbols at 1). */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002835 for (i = 1; i < mod->num_symtab; i++) {
2836 if (mod->symtab[i].st_shndx == SHN_UNDEF)
2837 continue;
2838
2839 /* We ignore unnamed symbols: they're uninformative
2840 * and inserted at a whim. */
2841 if (mod->symtab[i].st_value <= addr
2842 && mod->symtab[i].st_value > mod->symtab[best].st_value
2843 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2844 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2845 best = i;
2846 if (mod->symtab[i].st_value > addr
2847 && mod->symtab[i].st_value < nextval
2848 && *(mod->strtab + mod->symtab[i].st_name) != '\0'
2849 && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
2850 nextval = mod->symtab[i].st_value;
2851 }
2852
2853 if (!best)
2854 return NULL;
2855
Alexey Dobriyanffb45122007-05-08 00:28:41 -07002856 if (size)
2857 *size = nextval - mod->symtab[best].st_value;
2858 if (offset)
2859 *offset = addr - mod->symtab[best].st_value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002860 return mod->strtab + mod->symtab[best].st_name;
2861}
2862
Rusty Russell6dd06c92008-01-29 17:13:22 -05002863/* For kallsyms to ask for address resolution. NULL means not found. Careful
2864 * not to lock to avoid deadlock on oopses, simply disable preemption. */
Andrew Morton92dfc9d2008-02-08 04:18:43 -08002865const char *module_address_lookup(unsigned long addr,
Rusty Russell6dd06c92008-01-29 17:13:22 -05002866 unsigned long *size,
2867 unsigned long *offset,
2868 char **modname,
2869 char *namebuf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002870{
2871 struct module *mod;
Rusty Russellcb2a5202008-01-14 00:55:03 -08002872 const char *ret = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002873
Rusty Russellcb2a5202008-01-14 00:55:03 -08002874 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02002875 list_for_each_entry_rcu(mod, &modules, list) {
Masami Hiramatsua06f6212009-01-06 14:41:49 -08002876 if (within_module_init(addr, mod) ||
2877 within_module_core(addr, mod)) {
Franck Bui-Huuffc50892006-10-03 01:13:48 -07002878 if (modname)
2879 *modname = mod->name;
Rusty Russellcb2a5202008-01-14 00:55:03 -08002880 ret = get_ksymbol(mod, addr, size, offset);
2881 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002882 }
2883 }
Rusty Russell6dd06c92008-01-29 17:13:22 -05002884 /* Make a copy in here where it's safe */
2885 if (ret) {
2886 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
2887 ret = namebuf;
2888 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08002889 preempt_enable();
Andrew Morton92dfc9d2008-02-08 04:18:43 -08002890 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002891}
2892
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07002893int lookup_module_symbol_name(unsigned long addr, char *symname)
2894{
2895 struct module *mod;
2896
Rusty Russellcb2a5202008-01-14 00:55:03 -08002897 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02002898 list_for_each_entry_rcu(mod, &modules, list) {
Masami Hiramatsua06f6212009-01-06 14:41:49 -08002899 if (within_module_init(addr, mod) ||
2900 within_module_core(addr, mod)) {
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07002901 const char *sym;
2902
2903 sym = get_ksymbol(mod, addr, NULL, NULL);
2904 if (!sym)
2905 goto out;
Tejun Heo9281ace2007-07-17 04:03:51 -07002906 strlcpy(symname, sym, KSYM_NAME_LEN);
Rusty Russellcb2a5202008-01-14 00:55:03 -08002907 preempt_enable();
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07002908 return 0;
2909 }
2910 }
2911out:
Rusty Russellcb2a5202008-01-14 00:55:03 -08002912 preempt_enable();
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07002913 return -ERANGE;
2914}
2915
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07002916int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
2917 unsigned long *offset, char *modname, char *name)
2918{
2919 struct module *mod;
2920
Rusty Russellcb2a5202008-01-14 00:55:03 -08002921 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02002922 list_for_each_entry_rcu(mod, &modules, list) {
Masami Hiramatsua06f6212009-01-06 14:41:49 -08002923 if (within_module_init(addr, mod) ||
2924 within_module_core(addr, mod)) {
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07002925 const char *sym;
2926
2927 sym = get_ksymbol(mod, addr, size, offset);
2928 if (!sym)
2929 goto out;
2930 if (modname)
Tejun Heo9281ace2007-07-17 04:03:51 -07002931 strlcpy(modname, mod->name, MODULE_NAME_LEN);
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07002932 if (name)
Tejun Heo9281ace2007-07-17 04:03:51 -07002933 strlcpy(name, sym, KSYM_NAME_LEN);
Rusty Russellcb2a5202008-01-14 00:55:03 -08002934 preempt_enable();
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07002935 return 0;
2936 }
2937 }
2938out:
Rusty Russellcb2a5202008-01-14 00:55:03 -08002939 preempt_enable();
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07002940 return -ERANGE;
2941}
2942
Alexey Dobriyanea078902007-05-08 00:28:39 -07002943int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
2944 char *name, char *module_name, int *exported)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002945{
2946 struct module *mod;
2947
Rusty Russellcb2a5202008-01-14 00:55:03 -08002948 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02002949 list_for_each_entry_rcu(mod, &modules, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002950 if (symnum < mod->num_symtab) {
2951 *value = mod->symtab[symnum].st_value;
2952 *type = mod->symtab[symnum].st_info;
Andreas Gruenbacher098c5ee2006-07-14 00:24:04 -07002953 strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
Tejun Heo9281ace2007-07-17 04:03:51 -07002954 KSYM_NAME_LEN);
2955 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
Tim Abbottca4787b2009-01-05 08:40:10 -06002956 *exported = is_exported(name, *value, mod);
Rusty Russellcb2a5202008-01-14 00:55:03 -08002957 preempt_enable();
Alexey Dobriyanea078902007-05-08 00:28:39 -07002958 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002959 }
2960 symnum -= mod->num_symtab;
2961 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08002962 preempt_enable();
Alexey Dobriyanea078902007-05-08 00:28:39 -07002963 return -ERANGE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002964}
2965
2966static unsigned long mod_find_symname(struct module *mod, const char *name)
2967{
2968 unsigned int i;
2969
2970 for (i = 0; i < mod->num_symtab; i++)
Keith Owens54e8ce42006-02-03 03:03:53 -08002971 if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
2972 mod->symtab[i].st_info != 'U')
Linus Torvalds1da177e2005-04-16 15:20:36 -07002973 return mod->symtab[i].st_value;
2974 return 0;
2975}
2976
2977/* Look for this name: can be of form module:name. */
2978unsigned long module_kallsyms_lookup_name(const char *name)
2979{
2980 struct module *mod;
2981 char *colon;
2982 unsigned long ret = 0;
2983
2984 /* Don't lock: we're in enough trouble already. */
Rusty Russellcb2a5202008-01-14 00:55:03 -08002985 preempt_disable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002986 if ((colon = strchr(name, ':')) != NULL) {
2987 *colon = '\0';
2988 if ((mod = find_module(name)) != NULL)
2989 ret = mod_find_symname(mod, colon+1);
2990 *colon = ':';
2991 } else {
Andi Kleend72b3752008-08-30 10:09:00 +02002992 list_for_each_entry_rcu(mod, &modules, list)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002993 if ((ret = mod_find_symname(mod, name)) != 0)
2994 break;
2995 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08002996 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002997 return ret;
2998}
Anders Kaseorg75a66612008-12-05 19:03:58 -05002999
3000int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
3001 struct module *, unsigned long),
3002 void *data)
3003{
3004 struct module *mod;
3005 unsigned int i;
3006 int ret;
3007
3008 list_for_each_entry(mod, &modules, list) {
3009 for (i = 0; i < mod->num_symtab; i++) {
3010 ret = fn(data, mod->strtab + mod->symtab[i].st_name,
3011 mod, mod->symtab[i].st_value);
3012 if (ret != 0)
3013 return ret;
3014 }
3015 }
3016 return 0;
3017}
Linus Torvalds1da177e2005-04-16 15:20:36 -07003018#endif /* CONFIG_KALLSYMS */
3019
Arjan van de Ven21aa9282008-01-25 21:08:33 +01003020static char *module_flags(struct module *mod, char *buf)
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003021{
3022 int bx = 0;
3023
Arjan van de Ven21aa9282008-01-25 21:08:33 +01003024 if (mod->taints ||
3025 mod->state == MODULE_STATE_GOING ||
3026 mod->state == MODULE_STATE_COMING) {
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003027 buf[bx++] = '(';
Andi Kleen25ddbb12008-10-15 22:01:41 -07003028 if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003029 buf[bx++] = 'P';
Andi Kleen25ddbb12008-10-15 22:01:41 -07003030 if (mod->taints & (1 << TAINT_FORCED_MODULE))
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003031 buf[bx++] = 'F';
Linus Torvalds26e9a392008-10-17 09:50:12 -07003032 if (mod->taints & (1 << TAINT_CRAP))
Greg Kroah-Hartman061b1bd2008-09-24 14:46:44 -07003033 buf[bx++] = 'C';
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003034 /*
3035 * TAINT_FORCED_RMMOD: could be added.
3036 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
3037 * apply to modules.
3038 */
Arjan van de Ven21aa9282008-01-25 21:08:33 +01003039
3040 /* Show a - for module-is-being-unloaded */
3041 if (mod->state == MODULE_STATE_GOING)
3042 buf[bx++] = '-';
3043 /* Show a + for module-is-being-loaded */
3044 if (mod->state == MODULE_STATE_COMING)
3045 buf[bx++] = '+';
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003046 buf[bx++] = ')';
3047 }
3048 buf[bx] = '\0';
3049
3050 return buf;
3051}
3052
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04003053#ifdef CONFIG_PROC_FS
3054/* Called by the /proc file system to return a list of modules. */
3055static void *m_start(struct seq_file *m, loff_t *pos)
3056{
3057 mutex_lock(&module_mutex);
3058 return seq_list_start(&modules, *pos);
3059}
3060
3061static void *m_next(struct seq_file *m, void *p, loff_t *pos)
3062{
3063 return seq_list_next(p, &modules, pos);
3064}
3065
3066static void m_stop(struct seq_file *m, void *p)
3067{
3068 mutex_unlock(&module_mutex);
3069}
3070
Linus Torvalds1da177e2005-04-16 15:20:36 -07003071static int m_show(struct seq_file *m, void *p)
3072{
3073 struct module *mod = list_entry(p, struct module, list);
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003074 char buf[8];
3075
Denys Vlasenko2f0f2a32008-07-22 19:24:27 -05003076 seq_printf(m, "%s %u",
Linus Torvalds1da177e2005-04-16 15:20:36 -07003077 mod->name, mod->init_size + mod->core_size);
3078 print_unload_info(m, mod);
3079
3080 /* Informative for users. */
3081 seq_printf(m, " %s",
3082 mod->state == MODULE_STATE_GOING ? "Unloading":
3083 mod->state == MODULE_STATE_COMING ? "Loading":
3084 "Live");
3085 /* Used by oprofile and other similar tools. */
3086 seq_printf(m, " 0x%p", mod->module_core);
3087
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003088 /* Taints info */
3089 if (mod->taints)
Arjan van de Ven21aa9282008-01-25 21:08:33 +01003090 seq_printf(m, " %s", module_flags(mod, buf));
Florin Malitafa3ba2e82006-10-11 01:21:48 -07003091
Linus Torvalds1da177e2005-04-16 15:20:36 -07003092 seq_printf(m, "\n");
3093 return 0;
3094}
3095
3096/* Format: modulename size refcount deps address
3097
3098 Where refcount is a number or -, and deps is a comma-separated list
3099 of depends or -.
3100*/
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04003101static const struct seq_operations modules_op = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003102 .start = m_start,
3103 .next = m_next,
3104 .stop = m_stop,
3105 .show = m_show
3106};
3107
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04003108static int modules_open(struct inode *inode, struct file *file)
3109{
3110 return seq_open(file, &modules_op);
3111}
3112
3113static const struct file_operations proc_modules_operations = {
3114 .open = modules_open,
3115 .read = seq_read,
3116 .llseek = seq_lseek,
3117 .release = seq_release,
3118};
3119
3120static int __init proc_modules_init(void)
3121{
3122 proc_create("modules", 0, NULL, &proc_modules_operations);
3123 return 0;
3124}
3125module_init(proc_modules_init);
3126#endif
3127
Linus Torvalds1da177e2005-04-16 15:20:36 -07003128/* Given an address, look for it in the module exception tables. */
3129const struct exception_table_entry *search_module_extables(unsigned long addr)
3130{
Linus Torvalds1da177e2005-04-16 15:20:36 -07003131 const struct exception_table_entry *e = NULL;
3132 struct module *mod;
3133
Rusty Russell24da1cb2007-07-15 23:41:46 -07003134 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02003135 list_for_each_entry_rcu(mod, &modules, list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003136 if (mod->num_exentries == 0)
3137 continue;
Daniel Walker22a8bde2007-10-18 03:06:07 -07003138
Linus Torvalds1da177e2005-04-16 15:20:36 -07003139 e = search_extable(mod->extable,
3140 mod->extable + mod->num_exentries - 1,
3141 addr);
3142 if (e)
3143 break;
3144 }
Rusty Russell24da1cb2007-07-15 23:41:46 -07003145 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07003146
3147 /* Now, if we found one, we are running inside it now, hence
Daniel Walker22a8bde2007-10-18 03:06:07 -07003148 we cannot unload the module, hence no refcnt needed. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003149 return e;
3150}
3151
Ingo Molnar4d435f92006-07-03 00:24:24 -07003152/*
Rusty Russelle6104992009-03-31 13:05:31 -06003153 * is_module_address - is this address inside a module?
3154 * @addr: the address to check.
3155 *
3156 * See is_module_text_address() if you simply want to see if the address
3157 * is code (not data).
Ingo Molnar4d435f92006-07-03 00:24:24 -07003158 */
Rusty Russelle6104992009-03-31 13:05:31 -06003159bool is_module_address(unsigned long addr)
Ingo Molnar4d435f92006-07-03 00:24:24 -07003160{
Rusty Russelle6104992009-03-31 13:05:31 -06003161 bool ret;
Ingo Molnar4d435f92006-07-03 00:24:24 -07003162
Rusty Russell24da1cb2007-07-15 23:41:46 -07003163 preempt_disable();
Rusty Russelle6104992009-03-31 13:05:31 -06003164 ret = __module_address(addr) != NULL;
Rusty Russell24da1cb2007-07-15 23:41:46 -07003165 preempt_enable();
Ingo Molnar4d435f92006-07-03 00:24:24 -07003166
Rusty Russelle6104992009-03-31 13:05:31 -06003167 return ret;
Ingo Molnar4d435f92006-07-03 00:24:24 -07003168}
3169
Rusty Russelle6104992009-03-31 13:05:31 -06003170/*
3171 * __module_address - get the module which contains an address.
3172 * @addr: the address.
3173 *
3174 * Must be called with preempt disabled or module mutex held so that
3175 * module doesn't get freed during this.
3176 */
Linus Torvalds714f83d2009-04-05 11:04:19 -07003177struct module *__module_address(unsigned long addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003178{
3179 struct module *mod;
3180
Rusty Russell3a642e92008-07-22 19:24:28 -05003181 if (addr < module_addr_min || addr > module_addr_max)
3182 return NULL;
3183
Andi Kleend72b3752008-08-30 10:09:00 +02003184 list_for_each_entry_rcu(mod, &modules, list)
Rusty Russelle6104992009-03-31 13:05:31 -06003185 if (within_module_core(addr, mod)
3186 || within_module_init(addr, mod))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003187 return mod;
3188 return NULL;
3189}
Tim Abbottc6b37802008-12-05 19:03:59 -05003190EXPORT_SYMBOL_GPL(__module_address);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003191
Rusty Russelle6104992009-03-31 13:05:31 -06003192/*
3193 * is_module_text_address - is this address inside module code?
3194 * @addr: the address to check.
3195 *
3196 * See is_module_address() if you simply want to see if the address is
3197 * anywhere in a module. See kernel_text_address() for testing if an
3198 * address corresponds to kernel or module code.
3199 */
3200bool is_module_text_address(unsigned long addr)
3201{
3202 bool ret;
3203
3204 preempt_disable();
3205 ret = __module_text_address(addr) != NULL;
3206 preempt_enable();
3207
3208 return ret;
3209}
3210
3211/*
3212 * __module_text_address - get the module whose code contains an address.
3213 * @addr: the address.
3214 *
3215 * Must be called with preempt disabled or module mutex held so that
3216 * module doesn't get freed during this.
3217 */
3218struct module *__module_text_address(unsigned long addr)
3219{
3220 struct module *mod = __module_address(addr);
3221 if (mod) {
3222 /* Make sure it's within the text section. */
3223 if (!within(addr, mod->module_init, mod->init_text_size)
3224 && !within(addr, mod->module_core, mod->core_text_size))
3225 mod = NULL;
3226 }
3227 return mod;
3228}
Tim Abbottc6b37802008-12-05 19:03:59 -05003229EXPORT_SYMBOL_GPL(__module_text_address);
Rusty Russelle6104992009-03-31 13:05:31 -06003230
Linus Torvalds1da177e2005-04-16 15:20:36 -07003231/* Don't grab lock, we're oopsing. */
3232void print_modules(void)
3233{
3234 struct module *mod;
Randy Dunlap2bc2d612006-10-02 02:17:02 -07003235 char buf[8];
Linus Torvalds1da177e2005-04-16 15:20:36 -07003236
Linus Torvaldsb2311252009-06-16 11:07:14 -07003237 printk(KERN_DEFAULT "Modules linked in:");
Andi Kleend72b3752008-08-30 10:09:00 +02003238 /* Most callers should already have preempt disabled, but make sure */
3239 preempt_disable();
3240 list_for_each_entry_rcu(mod, &modules, list)
Arjan van de Ven21aa9282008-01-25 21:08:33 +01003241 printk(" %s%s", mod->name, module_flags(mod, buf));
Andi Kleend72b3752008-08-30 10:09:00 +02003242 preempt_enable();
Arjan van de Vene14af7e2008-01-25 21:08:33 +01003243 if (last_unloaded_module[0])
3244 printk(" [last unloaded: %s]", last_unloaded_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003245 printk("\n");
3246}
3247
Linus Torvalds1da177e2005-04-16 15:20:36 -07003248#ifdef CONFIG_MODVERSIONS
Rusty Russell8c8ef422009-03-31 13:05:34 -06003249/* Generate the signature for all relevant module structures here.
3250 * If these change, we don't want to try to parse the module. */
3251void module_layout(struct module *mod,
3252 struct modversion_info *ver,
3253 struct kernel_param *kp,
3254 struct kernel_symbol *ks,
Rusty Russell8c8ef422009-03-31 13:05:34 -06003255 struct tracepoint *tp)
3256{
3257}
3258EXPORT_SYMBOL(module_layout);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003259#endif
Mathieu Desnoyers8256e472007-10-18 23:41:06 -07003260
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -04003261#ifdef CONFIG_TRACEPOINTS
3262void module_update_tracepoints(void)
3263{
3264 struct module *mod;
3265
3266 mutex_lock(&module_mutex);
3267 list_for_each_entry(mod, &modules, list)
3268 if (!mod->taints)
3269 tracepoint_update_probe_range(mod->tracepoints,
3270 mod->tracepoints + mod->num_tracepoints);
3271 mutex_unlock(&module_mutex);
3272}
3273
3274/*
3275 * Returns 0 if current not found.
3276 * Returns 1 if current found.
3277 */
3278int module_get_iter_tracepoints(struct tracepoint_iter *iter)
3279{
3280 struct module *iter_mod;
3281 int found = 0;
3282
3283 mutex_lock(&module_mutex);
3284 list_for_each_entry(iter_mod, &modules, list) {
3285 if (!iter_mod->taints) {
3286 /*
3287 * Sorted module list
3288 */
3289 if (iter_mod < iter->module)
3290 continue;
3291 else if (iter_mod > iter->module)
3292 iter->tracepoint = NULL;
3293 found = tracepoint_get_iter_range(&iter->tracepoint,
3294 iter_mod->tracepoints,
3295 iter_mod->tracepoints
3296 + iter_mod->num_tracepoints);
3297 if (found) {
3298 iter->module = iter_mod;
3299 break;
3300 }
3301 }
3302 }
3303 mutex_unlock(&module_mutex);
3304 return found;
3305}
3306#endif