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authorLinus Torvalds <torvalds@linux-foundation.org>2008-05-01 11:26:56 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-05-01 11:26:56 -0400
commit03fc922f4085a0139f313831fe2dc6fed467cd2d (patch)
tree1404c800acaf02eab054eb3448803db9d9b89262
parenta0be7522b25f17ac2c3964a24b88b5fe7c9404b8 (diff)
parentdf4b565e1fbc777bb6e274378a41fa8ff7485680 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: module: add MODULE_STATE_GOING notifier call module: Enhance verify_export_symbols module: set unused_gpl_crcs instead of overwriting unused_crcs module: neaten __find_symbol, rename to find_symbol module: reduce module image and resident size module: make module_sect_attrs private to kernel/module.c
-rw-r--r--include/linux/module.h19
-rw-r--r--kernel/module.c319
2 files changed, 172 insertions, 166 deletions
diff --git a/include/linux/module.h b/include/linux/module.h
index 819c4e889bf1..3e03b1acbc94 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -190,7 +190,7 @@ void *__symbol_get_gpl(const char *symbol);
190 extern typeof(sym) sym; \ 190 extern typeof(sym) sym; \
191 __CRC_SYMBOL(sym, sec) \ 191 __CRC_SYMBOL(sym, sec) \
192 static const char __kstrtab_##sym[] \ 192 static const char __kstrtab_##sym[] \
193 __attribute__((section("__ksymtab_strings"))) \ 193 __attribute__((section("__ksymtab_strings"), aligned(1))) \
194 = MODULE_SYMBOL_PREFIX #sym; \ 194 = MODULE_SYMBOL_PREFIX #sym; \
195 static const struct kernel_symbol __ksymtab_##sym \ 195 static const struct kernel_symbol __ksymtab_##sym \
196 __used \ 196 __used \
@@ -229,23 +229,6 @@ enum module_state
229 MODULE_STATE_GOING, 229 MODULE_STATE_GOING,
230}; 230};
231 231
232/* Similar stuff for section attributes. */
233struct module_sect_attr
234{
235 struct module_attribute mattr;
236 char *name;
237 unsigned long address;
238};
239
240struct module_sect_attrs
241{
242 struct attribute_group grp;
243 int nsections;
244 struct module_sect_attr attrs[0];
245};
246
247struct module_param_attrs;
248
249struct module 232struct module
250{ 233{
251 enum module_state state; 234 enum module_state state;
diff --git a/kernel/module.c b/kernel/module.c
index 8d6cccc6c3cf..8674a390a2e8 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -164,131 +164,140 @@ static const struct kernel_symbol *lookup_symbol(const char *name,
164 return NULL; 164 return NULL;
165} 165}
166 166
167static void printk_unused_warning(const char *name) 167static bool always_ok(bool gplok, bool warn, const char *name)
168{ 168{
169 printk(KERN_WARNING "Symbol %s is marked as UNUSED, " 169 return true;
170 "however this module is using it.\n", name);
171 printk(KERN_WARNING "This symbol will go away in the future.\n");
172 printk(KERN_WARNING "Please evalute if this is the right api to use, "
173 "and if it really is, submit a report the linux kernel "
174 "mailinglist together with submitting your code for "
175 "inclusion.\n");
176} 170}
177 171
178/* Find a symbol, return value, crc and module which owns it */ 172static bool printk_unused_warning(bool gplok, bool warn, const char *name)
179static unsigned long __find_symbol(const char *name,
180 struct module **owner,
181 const unsigned long **crc,
182 int gplok)
183{ 173{
184 struct module *mod; 174 if (warn) {
185 const struct kernel_symbol *ks; 175 printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
186 176 "however this module is using it.\n", name);
187 /* Core kernel first. */ 177 printk(KERN_WARNING
188 *owner = NULL; 178 "This symbol will go away in the future.\n");
189 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab); 179 printk(KERN_WARNING
190 if (ks) { 180 "Please evalute if this is the right api to use and if "
191 *crc = symversion(__start___kcrctab, (ks - __start___ksymtab)); 181 "it really is, submit a report the linux kernel "
192 return ks->value; 182 "mailinglist together with submitting your code for "
183 "inclusion.\n");
193 } 184 }
194 if (gplok) { 185 return true;
195 ks = lookup_symbol(name, __start___ksymtab_gpl, 186}
196 __stop___ksymtab_gpl); 187
197 if (ks) { 188static bool gpl_only_unused_warning(bool gplok, bool warn, const char *name)
198 *crc = symversion(__start___kcrctab_gpl, 189{
199 (ks - __start___ksymtab_gpl)); 190 if (!gplok)
200 return ks->value; 191 return false;
201 } 192 return printk_unused_warning(gplok, warn, name);
202 } 193}
203 ks = lookup_symbol(name, __start___ksymtab_gpl_future, 194
204 __stop___ksymtab_gpl_future); 195static bool gpl_only(bool gplok, bool warn, const char *name)
205 if (ks) { 196{
206 if (!gplok) { 197 return gplok;
207 printk(KERN_WARNING "Symbol %s is being used " 198}
208 "by a non-GPL module, which will not " 199
209 "be allowed in the future\n", name); 200static bool warn_if_not_gpl(bool gplok, bool warn, const char *name)
210 printk(KERN_WARNING "Please see the file " 201{
211 "Documentation/feature-removal-schedule.txt " 202 if (!gplok && warn) {
212 "in the kernel source tree for more " 203 printk(KERN_WARNING "Symbol %s is being used "
213 "details.\n"); 204 "by a non-GPL module, which will not "
214 } 205 "be allowed in the future\n", name);
215 *crc = symversion(__start___kcrctab_gpl_future, 206 printk(KERN_WARNING "Please see the file "
216 (ks - __start___ksymtab_gpl_future)); 207 "Documentation/feature-removal-schedule.txt "
217 return ks->value; 208 "in the kernel source tree for more details.\n");
218 } 209 }
210 return true;
211}
219 212
220 ks = lookup_symbol(name, __start___ksymtab_unused, 213struct symsearch {
221 __stop___ksymtab_unused); 214 const struct kernel_symbol *start, *stop;
222 if (ks) { 215 const unsigned long *crcs;
223 printk_unused_warning(name); 216 bool (*check)(bool gplok, bool warn, const char *name);
224 *crc = symversion(__start___kcrctab_unused, 217};
225 (ks - __start___ksymtab_unused)); 218
226 return ks->value; 219/* Look through this array of symbol tables for a symbol match which
220 * passes the check function. */
221static const struct kernel_symbol *search_symarrays(const struct symsearch *arr,
222 unsigned int num,
223 const char *name,
224 bool gplok,
225 bool warn,
226 const unsigned long **crc)
227{
228 unsigned int i;
229 const struct kernel_symbol *ks;
230
231 for (i = 0; i < num; i++) {
232 ks = lookup_symbol(name, arr[i].start, arr[i].stop);
233 if (!ks || !arr[i].check(gplok, warn, name))
234 continue;
235
236 if (crc)
237 *crc = symversion(arr[i].crcs, ks - arr[i].start);
238 return ks;
227 } 239 }
240 return NULL;
241}
242
243/* Find a symbol, return value, (optional) crc and (optional) module
244 * which owns it */
245static unsigned long find_symbol(const char *name,
246 struct module **owner,
247 const unsigned long **crc,
248 bool gplok,
249 bool warn)
250{
251 struct module *mod;
252 const struct kernel_symbol *ks;
253 const struct symsearch arr[] = {
254 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
255 always_ok },
256 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
257 __start___kcrctab_gpl, gpl_only },
258 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
259 __start___kcrctab_gpl_future, warn_if_not_gpl },
260 { __start___ksymtab_unused, __stop___ksymtab_unused,
261 __start___kcrctab_unused, printk_unused_warning },
262 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
263 __start___kcrctab_unused_gpl, gpl_only_unused_warning },
264 };
228 265
229 if (gplok) 266 /* Core kernel first. */
230 ks = lookup_symbol(name, __start___ksymtab_unused_gpl, 267 ks = search_symarrays(arr, ARRAY_SIZE(arr), name, gplok, warn, crc);
231 __stop___ksymtab_unused_gpl);
232 if (ks) { 268 if (ks) {
233 printk_unused_warning(name); 269 if (owner)
234 *crc = symversion(__start___kcrctab_unused_gpl, 270 *owner = NULL;
235 (ks - __start___ksymtab_unused_gpl));
236 return ks->value; 271 return ks->value;
237 } 272 }
238 273
239 /* Now try modules. */ 274 /* Now try modules. */
240 list_for_each_entry(mod, &modules, list) { 275 list_for_each_entry(mod, &modules, list) {
241 *owner = mod; 276 struct symsearch arr[] = {
242 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms); 277 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
243 if (ks) { 278 always_ok },
244 *crc = symversion(mod->crcs, (ks - mod->syms)); 279 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
245 return ks->value; 280 mod->gpl_crcs, gpl_only },
246 } 281 { mod->gpl_future_syms,
247 282 mod->gpl_future_syms + mod->num_gpl_future_syms,
248 if (gplok) { 283 mod->gpl_future_crcs, warn_if_not_gpl },
249 ks = lookup_symbol(name, mod->gpl_syms, 284 { mod->unused_syms,
250 mod->gpl_syms + mod->num_gpl_syms); 285 mod->unused_syms + mod->num_unused_syms,
251 if (ks) { 286 mod->unused_crcs, printk_unused_warning },
252 *crc = symversion(mod->gpl_crcs, 287 { mod->unused_gpl_syms,
253 (ks - mod->gpl_syms)); 288 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
254 return ks->value; 289 mod->unused_gpl_crcs, gpl_only_unused_warning },
255 } 290 };
256 } 291
257 ks = lookup_symbol(name, mod->unused_syms, mod->unused_syms + mod->num_unused_syms); 292 ks = search_symarrays(arr, ARRAY_SIZE(arr),
293 name, gplok, warn, crc);
258 if (ks) { 294 if (ks) {
259 printk_unused_warning(name); 295 if (owner)
260 *crc = symversion(mod->unused_crcs, (ks - mod->unused_syms)); 296 *owner = mod;
261 return ks->value;
262 }
263
264 if (gplok) {
265 ks = lookup_symbol(name, mod->unused_gpl_syms,
266 mod->unused_gpl_syms + mod->num_unused_gpl_syms);
267 if (ks) {
268 printk_unused_warning(name);
269 *crc = symversion(mod->unused_gpl_crcs,
270 (ks - mod->unused_gpl_syms));
271 return ks->value;
272 }
273 }
274 ks = lookup_symbol(name, mod->gpl_future_syms,
275 (mod->gpl_future_syms +
276 mod->num_gpl_future_syms));
277 if (ks) {
278 if (!gplok) {
279 printk(KERN_WARNING "Symbol %s is being used "
280 "by a non-GPL module, which will not "
281 "be allowed in the future\n", name);
282 printk(KERN_WARNING "Please see the file "
283 "Documentation/feature-removal-schedule.txt "
284 "in the kernel source tree for more "
285 "details.\n");
286 }
287 *crc = symversion(mod->gpl_future_crcs,
288 (ks - mod->gpl_future_syms));
289 return ks->value; 297 return ks->value;
290 } 298 }
291 } 299 }
300
292 DEBUGP("Failed to find symbol %s\n", name); 301 DEBUGP("Failed to find symbol %s\n", name);
293 return -ENOENT; 302 return -ENOENT;
294} 303}
@@ -736,12 +745,13 @@ sys_delete_module(const char __user *name_user, unsigned int flags)
736 if (!forced && module_refcount(mod) != 0) 745 if (!forced && module_refcount(mod) != 0)
737 wait_for_zero_refcount(mod); 746 wait_for_zero_refcount(mod);
738 747
748 mutex_unlock(&module_mutex);
739 /* Final destruction now noone is using it. */ 749 /* Final destruction now noone is using it. */
740 if (mod->exit != NULL) { 750 if (mod->exit != NULL)
741 mutex_unlock(&module_mutex);
742 mod->exit(); 751 mod->exit();
743 mutex_lock(&module_mutex); 752 blocking_notifier_call_chain(&module_notify_list,
744 } 753 MODULE_STATE_GOING, mod);
754 mutex_lock(&module_mutex);
745 /* Store the name of the last unloaded module for diagnostic purposes */ 755 /* Store the name of the last unloaded module for diagnostic purposes */
746 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); 756 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
747 free_module(mod); 757 free_module(mod);
@@ -777,10 +787,9 @@ static void print_unload_info(struct seq_file *m, struct module *mod)
777void __symbol_put(const char *symbol) 787void __symbol_put(const char *symbol)
778{ 788{
779 struct module *owner; 789 struct module *owner;
780 const unsigned long *crc;
781 790
782 preempt_disable(); 791 preempt_disable();
783 if (IS_ERR_VALUE(__find_symbol(symbol, &owner, &crc, 1))) 792 if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false)))
784 BUG(); 793 BUG();
785 module_put(owner); 794 module_put(owner);
786 preempt_enable(); 795 preempt_enable();
@@ -924,13 +933,10 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs,
924 struct module *mod) 933 struct module *mod)
925{ 934{
926 const unsigned long *crc; 935 const unsigned long *crc;
927 struct module *owner;
928 936
929 if (IS_ERR_VALUE(__find_symbol("struct_module", 937 if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false)))
930 &owner, &crc, 1)))
931 BUG(); 938 BUG();
932 return check_version(sechdrs, versindex, "struct_module", mod, 939 return check_version(sechdrs, versindex, "struct_module", mod, crc);
933 crc);
934} 940}
935 941
936/* First part is kernel version, which we ignore. */ 942/* First part is kernel version, which we ignore. */
@@ -974,8 +980,8 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
974 unsigned long ret; 980 unsigned long ret;
975 const unsigned long *crc; 981 const unsigned long *crc;
976 982
977 ret = __find_symbol(name, &owner, &crc, 983 ret = find_symbol(name, &owner, &crc,
978 !(mod->taints & TAINT_PROPRIETARY_MODULE)); 984 !(mod->taints & TAINT_PROPRIETARY_MODULE), true);
979 if (!IS_ERR_VALUE(ret)) { 985 if (!IS_ERR_VALUE(ret)) {
980 /* use_module can fail due to OOM, 986 /* use_module can fail due to OOM,
981 or module initialization or unloading */ 987 or module initialization or unloading */
@@ -991,6 +997,20 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
991 * J. Corbet <corbet@lwn.net> 997 * J. Corbet <corbet@lwn.net>
992 */ 998 */
993#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS) 999#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1000struct module_sect_attr
1001{
1002 struct module_attribute mattr;
1003 char *name;
1004 unsigned long address;
1005};
1006
1007struct module_sect_attrs
1008{
1009 struct attribute_group grp;
1010 unsigned int nsections;
1011 struct module_sect_attr attrs[0];
1012};
1013
994static ssize_t module_sect_show(struct module_attribute *mattr, 1014static ssize_t module_sect_show(struct module_attribute *mattr,
995 struct module *mod, char *buf) 1015 struct module *mod, char *buf)
996{ 1016{
@@ -1001,7 +1021,7 @@ static ssize_t module_sect_show(struct module_attribute *mattr,
1001 1021
1002static void free_sect_attrs(struct module_sect_attrs *sect_attrs) 1022static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1003{ 1023{
1004 int section; 1024 unsigned int section;
1005 1025
1006 for (section = 0; section < sect_attrs->nsections; section++) 1026 for (section = 0; section < sect_attrs->nsections; section++)
1007 kfree(sect_attrs->attrs[section].name); 1027 kfree(sect_attrs->attrs[section].name);
@@ -1362,10 +1382,9 @@ void *__symbol_get(const char *symbol)
1362{ 1382{
1363 struct module *owner; 1383 struct module *owner;
1364 unsigned long value; 1384 unsigned long value;
1365 const unsigned long *crc;
1366 1385
1367 preempt_disable(); 1386 preempt_disable();
1368 value = __find_symbol(symbol, &owner, &crc, 1); 1387 value = find_symbol(symbol, &owner, NULL, true, true);
1369 if (IS_ERR_VALUE(value)) 1388 if (IS_ERR_VALUE(value))
1370 value = 0; 1389 value = 0;
1371 else if (strong_try_module_get(owner)) 1390 else if (strong_try_module_get(owner))
@@ -1382,33 +1401,33 @@ EXPORT_SYMBOL_GPL(__symbol_get);
1382 */ 1401 */
1383static int verify_export_symbols(struct module *mod) 1402static int verify_export_symbols(struct module *mod)
1384{ 1403{
1385 const char *name = NULL; 1404 unsigned int i;
1386 unsigned long i, ret = 0;
1387 struct module *owner; 1405 struct module *owner;
1388 const unsigned long *crc; 1406 const struct kernel_symbol *s;
1389 1407 struct {
1390 for (i = 0; i < mod->num_syms; i++) 1408 const struct kernel_symbol *sym;
1391 if (!IS_ERR_VALUE(__find_symbol(mod->syms[i].name, 1409 unsigned int num;
1392 &owner, &crc, 1))) { 1410 } arr[] = {
1393 name = mod->syms[i].name; 1411 { mod->syms, mod->num_syms },
1394 ret = -ENOEXEC; 1412 { mod->gpl_syms, mod->num_gpl_syms },
1395 goto dup; 1413 { mod->gpl_future_syms, mod->num_gpl_future_syms },
1396 } 1414 { mod->unused_syms, mod->num_unused_syms },
1415 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1416 };
1397 1417
1398 for (i = 0; i < mod->num_gpl_syms; i++) 1418 for (i = 0; i < ARRAY_SIZE(arr); i++) {
1399 if (!IS_ERR_VALUE(__find_symbol(mod->gpl_syms[i].name, 1419 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1400 &owner, &crc, 1))) { 1420 if (!IS_ERR_VALUE(find_symbol(s->name, &owner,
1401 name = mod->gpl_syms[i].name; 1421 NULL, true, false))) {
1402 ret = -ENOEXEC; 1422 printk(KERN_ERR
1403 goto dup; 1423 "%s: exports duplicate symbol %s"
1424 " (owned by %s)\n",
1425 mod->name, s->name, module_name(owner));
1426 return -ENOEXEC;
1427 }
1404 } 1428 }
1405 1429 }
1406dup: 1430 return 0;
1407 if (ret)
1408 printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
1409 mod->name, name, module_name(owner));
1410
1411 return ret;
1412} 1431}
1413 1432
1414/* Change all symbols so that st_value encodes the pointer directly. */ 1433/* Change all symbols so that st_value encodes the pointer directly. */
@@ -1814,8 +1833,9 @@ static struct module *load_module(void __user *umod,
1814 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME); 1833 unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
1815#endif 1834#endif
1816 1835
1817 /* Don't keep modinfo section */ 1836 /* Don't keep modinfo and version sections. */
1818 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC; 1837 sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1838 sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
1819#ifdef CONFIG_KALLSYMS 1839#ifdef CONFIG_KALLSYMS
1820 /* Keep symbol and string tables for decoding later. */ 1840 /* Keep symbol and string tables for decoding later. */
1821 sechdrs[symindex].sh_flags |= SHF_ALLOC; 1841 sechdrs[symindex].sh_flags |= SHF_ALLOC;
@@ -1977,7 +1997,8 @@ static struct module *load_module(void __user *umod,
1977 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr; 1997 mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
1978 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr; 1998 mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
1979 if (unusedgplcrcindex) 1999 if (unusedgplcrcindex)
1980 mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr; 2000 mod->unused_gpl_crcs
2001 = (void *)sechdrs[unusedgplcrcindex].sh_addr;
1981 2002
1982#ifdef CONFIG_MODVERSIONS 2003#ifdef CONFIG_MODVERSIONS
1983 if ((mod->num_syms && !crcindex) || 2004 if ((mod->num_syms && !crcindex) ||
@@ -2171,6 +2192,8 @@ sys_init_module(void __user *umod,
2171 mod->state = MODULE_STATE_GOING; 2192 mod->state = MODULE_STATE_GOING;
2172 synchronize_sched(); 2193 synchronize_sched();
2173 module_put(mod); 2194 module_put(mod);
2195 blocking_notifier_call_chain(&module_notify_list,
2196 MODULE_STATE_GOING, mod);
2174 mutex_lock(&module_mutex); 2197 mutex_lock(&module_mutex);
2175 free_module(mod); 2198 free_module(mod);
2176 mutex_unlock(&module_mutex); 2199 mutex_unlock(&module_mutex);