X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Fmodule.c;h=5f80478b746d4eeb1a1dc92040c1e8eacd31bc34;hb=475433be3d8f4d840e2930eef96671b7f8d11053;hp=b0d7c2a41bd9120c324e19eae0cf8ad8d148d1d7;hpb=a58730c42174672fe0012a4edbe3e38f94ef2bad;p=safe%2Fjmp%2Flinux-2.6

diff --git a/kernel/module.c b/kernel/module.c
index b0d7c2a..5f80478 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -164,131 +164,140 @@ static const struct kernel_symbol *lookup_symbol(const char *name,
 	return NULL;
 }
 
-static void printk_unused_warning(const char *name)
+static bool always_ok(bool gplok, bool warn, const char *name)
 {
-	printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
-		"however this module is using it.\n", name);
-	printk(KERN_WARNING "This symbol will go away in the future.\n");
-	printk(KERN_WARNING "Please evalute if this is the right api to use, "
-		"and if it really is, submit a report the linux kernel "
-		"mailinglist together with submitting your code for "
-		"inclusion.\n");
+	return true;
 }
 
-/* Find a symbol, return value, crc and module which owns it */
-static unsigned long __find_symbol(const char *name,
-				   struct module **owner,
-				   const unsigned long **crc,
-				   int gplok)
+static bool printk_unused_warning(bool gplok, bool warn, const char *name)
 {
-	struct module *mod;
-	const struct kernel_symbol *ks;
-
-	/* Core kernel first. */
-	*owner = NULL;
-	ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
-	if (ks) {
-		*crc = symversion(__start___kcrctab, (ks - __start___ksymtab));
-		return ks->value;
+	if (warn) {
+		printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
+		       "however this module is using it.\n", name);
+		printk(KERN_WARNING
+		       "This symbol will go away in the future.\n");
+		printk(KERN_WARNING
+		       "Please evalute if this is the right api to use and if "
+		       "it really is, submit a report the linux kernel "
+		       "mailinglist together with submitting your code for "
+		       "inclusion.\n");
 	}
-	if (gplok) {
-		ks = lookup_symbol(name, __start___ksymtab_gpl,
-					 __stop___ksymtab_gpl);
-		if (ks) {
-			*crc = symversion(__start___kcrctab_gpl,
-					  (ks - __start___ksymtab_gpl));
-			return ks->value;
-		}
-	}
-	ks = lookup_symbol(name, __start___ksymtab_gpl_future,
-				 __stop___ksymtab_gpl_future);
-	if (ks) {
-		if (!gplok) {
-			printk(KERN_WARNING "Symbol %s is being used "
-			       "by a non-GPL module, which will not "
-			       "be allowed in the future\n", name);
-			printk(KERN_WARNING "Please see the file "
-			       "Documentation/feature-removal-schedule.txt "
-			       "in the kernel source tree for more "
-			       "details.\n");
-		}
-		*crc = symversion(__start___kcrctab_gpl_future,
-				  (ks - __start___ksymtab_gpl_future));
-		return ks->value;
+	return true;
+}
+
+static bool gpl_only_unused_warning(bool gplok, bool warn, const char *name)
+{
+	if (!gplok)
+		return false;
+	return printk_unused_warning(gplok, warn, name);
+}
+
+static bool gpl_only(bool gplok, bool warn, const char *name)
+{
+	return gplok;
+}
+
+static bool warn_if_not_gpl(bool gplok, bool warn, const char *name)
+{
+	if (!gplok && warn) {
+		printk(KERN_WARNING "Symbol %s is being used "
+		       "by a non-GPL module, which will not "
+		       "be allowed in the future\n", name);
+		printk(KERN_WARNING "Please see the file "
+		       "Documentation/feature-removal-schedule.txt "
+		       "in the kernel source tree for more details.\n");
 	}
+	return true;
+}
 
-	ks = lookup_symbol(name, __start___ksymtab_unused,
-				 __stop___ksymtab_unused);
-	if (ks) {
-		printk_unused_warning(name);
-		*crc = symversion(__start___kcrctab_unused,
-				  (ks - __start___ksymtab_unused));
-		return ks->value;
+struct symsearch {
+	const struct kernel_symbol *start, *stop;
+	const unsigned long *crcs;
+	bool (*check)(bool gplok, bool warn, const char *name);
+};
+
+/* Look through this array of symbol tables for a symbol match which
+ * passes the check function. */
+static const struct kernel_symbol *search_symarrays(const struct symsearch *arr,
+						    unsigned int num,
+						    const char *name,
+						    bool gplok,
+						    bool warn,
+						    const unsigned long **crc)
+{
+	unsigned int i;
+	const struct kernel_symbol *ks;
+
+	for (i = 0; i < num; i++) {
+		ks = lookup_symbol(name, arr[i].start, arr[i].stop);
+		if (!ks || !arr[i].check(gplok, warn, name))
+			continue;
+
+		if (crc)
+			*crc = symversion(arr[i].crcs, ks - arr[i].start);
+		return ks;
 	}
+	return NULL;
+}
+
+/* Find a symbol, return value, (optional) crc and (optional) module
+ * which owns it */
+static unsigned long find_symbol(const char *name,
+				 struct module **owner,
+				 const unsigned long **crc,
+				 bool gplok,
+				 bool warn)
+{
+	struct module *mod;
+	const struct kernel_symbol *ks;
+	const struct symsearch arr[] = {
+		{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
+		  always_ok },
+		{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
+		  __start___kcrctab_gpl, gpl_only },
+		{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
+		  __start___kcrctab_gpl_future, warn_if_not_gpl },
+		{ __start___ksymtab_unused, __stop___ksymtab_unused,
+		  __start___kcrctab_unused, printk_unused_warning },
+		{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
+		  __start___kcrctab_unused_gpl, gpl_only_unused_warning },
+	};
 
-	if (gplok)
-		ks = lookup_symbol(name, __start___ksymtab_unused_gpl,
-				 __stop___ksymtab_unused_gpl);
+	/* Core kernel first. */
+	ks = search_symarrays(arr, ARRAY_SIZE(arr), name, gplok, warn, crc);
 	if (ks) {
-		printk_unused_warning(name);
-		*crc = symversion(__start___kcrctab_unused_gpl,
-				  (ks - __start___ksymtab_unused_gpl));
+		if (owner)
+			*owner = NULL;
 		return ks->value;
 	}
 
 	/* Now try modules. */
 	list_for_each_entry(mod, &modules, list) {
-		*owner = mod;
-		ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
-		if (ks) {
-			*crc = symversion(mod->crcs, (ks - mod->syms));
-			return ks->value;
-		}
-
-		if (gplok) {
-			ks = lookup_symbol(name, mod->gpl_syms,
-					   mod->gpl_syms + mod->num_gpl_syms);
-			if (ks) {
-				*crc = symversion(mod->gpl_crcs,
-						  (ks - mod->gpl_syms));
-				return ks->value;
-			}
-		}
-		ks = lookup_symbol(name, mod->unused_syms, mod->unused_syms + mod->num_unused_syms);
-		if (ks) {
-			printk_unused_warning(name);
-			*crc = symversion(mod->unused_crcs, (ks - mod->unused_syms));
-			return ks->value;
-		}
-
-		if (gplok) {
-			ks = lookup_symbol(name, mod->unused_gpl_syms,
-					   mod->unused_gpl_syms + mod->num_unused_gpl_syms);
-			if (ks) {
-				printk_unused_warning(name);
-				*crc = symversion(mod->unused_gpl_crcs,
-						  (ks - mod->unused_gpl_syms));
-				return ks->value;
-			}
-		}
-		ks = lookup_symbol(name, mod->gpl_future_syms,
-				   (mod->gpl_future_syms +
-				    mod->num_gpl_future_syms));
+		struct symsearch arr[] = {
+			{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
+			  always_ok },
+			{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
+			  mod->gpl_crcs, gpl_only },
+			{ mod->gpl_future_syms,
+			  mod->gpl_future_syms + mod->num_gpl_future_syms,
+			  mod->gpl_future_crcs, warn_if_not_gpl },
+			{ mod->unused_syms,
+			  mod->unused_syms + mod->num_unused_syms,
+			  mod->unused_crcs, printk_unused_warning },
+			{ mod->unused_gpl_syms,
+			  mod->unused_gpl_syms + mod->num_unused_gpl_syms,
+			  mod->unused_gpl_crcs, gpl_only_unused_warning },
+		};
+
+		ks = search_symarrays(arr, ARRAY_SIZE(arr),
+				      name, gplok, warn, crc);
 		if (ks) {
-			if (!gplok) {
-				printk(KERN_WARNING "Symbol %s is being used "
-				       "by a non-GPL module, which will not "
-				       "be allowed in the future\n", name);
-				printk(KERN_WARNING "Please see the file "
-				       "Documentation/feature-removal-schedule.txt "
-				       "in the kernel source tree for more "
-				       "details.\n");
-			}
-			*crc = symversion(mod->gpl_future_crcs,
-					  (ks - mod->gpl_future_syms));
+			if (owner)
+				*owner = mod;
 			return ks->value;
 		}
 	}
+
 	DEBUGP("Failed to find symbol %s\n", name);
 	return -ENOENT;
 }
@@ -736,12 +745,13 @@ sys_delete_module(const char __user *name_user, unsigned int flags)
 	if (!forced && module_refcount(mod) != 0)
 		wait_for_zero_refcount(mod);
 
+	mutex_unlock(&module_mutex);
 	/* Final destruction now noone is using it. */
-	if (mod->exit != NULL) {
-		mutex_unlock(&module_mutex);
+	if (mod->exit != NULL)
 		mod->exit();
-		mutex_lock(&module_mutex);
-	}
+	blocking_notifier_call_chain(&module_notify_list,
+				     MODULE_STATE_GOING, mod);
+	mutex_lock(&module_mutex);
 	/* Store the name of the last unloaded module for diagnostic purposes */
 	strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
 	free_module(mod);
@@ -777,10 +787,9 @@ static void print_unload_info(struct seq_file *m, struct module *mod)
 void __symbol_put(const char *symbol)
 {
 	struct module *owner;
-	const unsigned long *crc;
 
 	preempt_disable();
-	if (IS_ERR_VALUE(__find_symbol(symbol, &owner, &crc, 1)))
+	if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false)))
 		BUG();
 	module_put(owner);
 	preempt_enable();
@@ -881,6 +890,19 @@ static struct module_attribute *modinfo_attrs[] = {
 
 static const char vermagic[] = VERMAGIC_STRING;
 
+static int try_to_force_load(struct module *mod, const char *symname)
+{
+#ifdef CONFIG_MODULE_FORCE_LOAD
+	if (!(tainted & TAINT_FORCED_MODULE))
+		printk("%s: no version for \"%s\" found: kernel tainted.\n",
+		       mod->name, symname);
+	add_taint_module(mod, TAINT_FORCED_MODULE);
+	return 0;
+#else
+	return -ENOEXEC;
+#endif
+}
+
 #ifdef CONFIG_MODVERSIONS
 static int check_version(Elf_Shdr *sechdrs,
 			 unsigned int versindex,
@@ -895,6 +917,10 @@ static int check_version(Elf_Shdr *sechdrs,
 	if (!crc)
 		return 1;
 
+	/* No versions at all?  modprobe --force does this. */
+	if (versindex == 0)
+		return try_to_force_load(mod, symname) == 0;
+
 	versions = (void *) sechdrs[versindex].sh_addr;
 	num_versions = sechdrs[versindex].sh_size
 		/ sizeof(struct modversion_info);
@@ -905,18 +931,19 @@ static int check_version(Elf_Shdr *sechdrs,
 
 		if (versions[i].crc == *crc)
 			return 1;
-		printk("%s: disagrees about version of symbol %s\n",
-		       mod->name, symname);
 		DEBUGP("Found checksum %lX vs module %lX\n",
 		       *crc, versions[i].crc);
-		return 0;
+		goto bad_version;
 	}
-	/* Not in module's version table.  OK, but that taints the kernel. */
-	if (!(tainted & TAINT_FORCED_MODULE))
-		printk("%s: no version for \"%s\" found: kernel tainted.\n",
-		       mod->name, symname);
-	add_taint_module(mod, TAINT_FORCED_MODULE);
-	return 1;
+
+	printk(KERN_WARNING "%s: no symbol version for %s\n",
+	       mod->name, symname);
+	return 0;
+
+bad_version:
+	printk("%s: disagrees about version of symbol %s\n",
+	       mod->name, symname);
+	return 0;
 }
 
 static inline int check_modstruct_version(Elf_Shdr *sechdrs,
@@ -924,20 +951,20 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs,
 					  struct module *mod)
 {
 	const unsigned long *crc;
-	struct module *owner;
 
-	if (IS_ERR_VALUE(__find_symbol("struct_module",
-						&owner, &crc, 1)))
+	if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false)))
 		BUG();
-	return check_version(sechdrs, versindex, "struct_module", mod,
-			     crc);
+	return check_version(sechdrs, versindex, "struct_module", mod, crc);
 }
 
-/* First part is kernel version, which we ignore. */
-static inline int same_magic(const char *amagic, const char *bmagic)
+/* First part is kernel version, which we ignore if module has crcs. */
+static inline int same_magic(const char *amagic, const char *bmagic,
+			     bool has_crcs)
 {
-	amagic += strcspn(amagic, " ");
-	bmagic += strcspn(bmagic, " ");
+	if (has_crcs) {
+		amagic += strcspn(amagic, " ");
+		bmagic += strcspn(bmagic, " ");
+	}
 	return strcmp(amagic, bmagic) == 0;
 }
 #else
@@ -957,7 +984,8 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs,
 	return 1;
 }
 
-static inline int same_magic(const char *amagic, const char *bmagic)
+static inline int same_magic(const char *amagic, const char *bmagic,
+			     bool has_crcs)
 {
 	return strcmp(amagic, bmagic) == 0;
 }
@@ -974,8 +1002,8 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
 	unsigned long ret;
 	const unsigned long *crc;
 
-	ret = __find_symbol(name, &owner, &crc,
-			!(mod->taints & TAINT_PROPRIETARY_MODULE));
+	ret = find_symbol(name, &owner, &crc,
+			  !(mod->taints & TAINT_PROPRIETARY_MODULE), true);
 	if (!IS_ERR_VALUE(ret)) {
 		/* use_module can fail due to OOM,
 		   or module initialization or unloading */
@@ -1309,7 +1337,19 @@ out_unreg:
 	kobject_put(&mod->mkobj.kobj);
 	return err;
 }
-#endif
+
+static void mod_sysfs_fini(struct module *mod)
+{
+	kobject_put(&mod->mkobj.kobj);
+}
+
+#else /* CONFIG_SYSFS */
+
+static void mod_sysfs_fini(struct module *mod)
+{
+}
+
+#endif /* CONFIG_SYSFS */
 
 static void mod_kobject_remove(struct module *mod)
 {
@@ -1317,7 +1357,7 @@ static void mod_kobject_remove(struct module *mod)
 	module_param_sysfs_remove(mod);
 	kobject_put(mod->mkobj.drivers_dir);
 	kobject_put(mod->holders_dir);
-	kobject_put(&mod->mkobj.kobj);
+	mod_sysfs_fini(mod);
 }
 
 /*
@@ -1376,10 +1416,9 @@ void *__symbol_get(const char *symbol)
 {
 	struct module *owner;
 	unsigned long value;
-	const unsigned long *crc;
 
 	preempt_disable();
-	value = __find_symbol(symbol, &owner, &crc, 1);
+	value = find_symbol(symbol, &owner, NULL, true, true);
 	if (IS_ERR_VALUE(value))
 		value = 0;
 	else if (strong_try_module_get(owner))
@@ -1396,33 +1435,33 @@ EXPORT_SYMBOL_GPL(__symbol_get);
  */
 static int verify_export_symbols(struct module *mod)
 {
-	const char *name = NULL;
-	unsigned long i, ret = 0;
+	unsigned int i;
 	struct module *owner;
-	const unsigned long *crc;
-
-	for (i = 0; i < mod->num_syms; i++)
-		if (!IS_ERR_VALUE(__find_symbol(mod->syms[i].name,
-							&owner, &crc, 1))) {
-			name = mod->syms[i].name;
-			ret = -ENOEXEC;
-			goto dup;
-		}
+	const struct kernel_symbol *s;
+	struct {
+		const struct kernel_symbol *sym;
+		unsigned int num;
+	} arr[] = {
+		{ mod->syms, mod->num_syms },
+		{ mod->gpl_syms, mod->num_gpl_syms },
+		{ mod->gpl_future_syms, mod->num_gpl_future_syms },
+		{ mod->unused_syms, mod->num_unused_syms },
+		{ mod->unused_gpl_syms, mod->num_unused_gpl_syms },
+	};
 
-	for (i = 0; i < mod->num_gpl_syms; i++)
-		if (!IS_ERR_VALUE(__find_symbol(mod->gpl_syms[i].name,
-							&owner, &crc, 1))) {
-			name = mod->gpl_syms[i].name;
-			ret = -ENOEXEC;
-			goto dup;
+	for (i = 0; i < ARRAY_SIZE(arr); i++) {
+		for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
+			if (!IS_ERR_VALUE(find_symbol(s->name, &owner,
+						      NULL, true, false))) {
+				printk(KERN_ERR
+				       "%s: exports duplicate symbol %s"
+				       " (owned by %s)\n",
+				       mod->name, s->name, module_name(owner));
+				return -ENOEXEC;
+			}
 		}
-
-dup:
-	if (ret)
-		printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
-			mod->name, name, module_name(owner));
-
-	return ret;
+	}
+	return 0;
 }
 
 /* Change all symbols so that st_value encodes the pointer directly. */
@@ -1753,7 +1792,7 @@ static struct module *load_module(void __user *umod,
 
 	/* Sanity checks against insmoding binaries or wrong arch,
            weird elf version */
-	if (memcmp(hdr->e_ident, ELFMAG, 4) != 0
+	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
 	    || hdr->e_type != ET_REL
 	    || !elf_check_arch(hdr)
 	    || hdr->e_shentsize != sizeof(*sechdrs)) {
@@ -1828,8 +1867,9 @@ static struct module *load_module(void __user *umod,
 	unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
 #endif
 
-	/* Don't keep modinfo section */
+	/* Don't keep modinfo and version sections. */
 	sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
+	sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
 #ifdef CONFIG_KALLSYMS
 	/* Keep symbol and string tables for decoding later. */
 	sechdrs[symindex].sh_flags |= SHF_ALLOC;
@@ -1847,10 +1887,10 @@ static struct module *load_module(void __user *umod,
 	modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
 	/* This is allowed: modprobe --force will invalidate it. */
 	if (!modmagic) {
-		add_taint_module(mod, TAINT_FORCED_MODULE);
-		printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
-		       mod->name);
-	} else if (!same_magic(modmagic, vermagic)) {
+		err = try_to_force_load(mod, "magic");
+		if (err)
+			goto free_hdr;
+	} else if (!same_magic(modmagic, vermagic, versindex)) {
 		printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
 		       mod->name, modmagic, vermagic);
 		err = -ENOEXEC;
@@ -1991,7 +2031,8 @@ static struct module *load_module(void __user *umod,
 		mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
 	mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
 	if (unusedgplcrcindex)
-		mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr;
+		mod->unused_gpl_crcs
+			= (void *)sechdrs[unusedgplcrcindex].sh_addr;
 
 #ifdef CONFIG_MODVERSIONS
 	if ((mod->num_syms && !crcindex) ||
@@ -1999,9 +2040,10 @@ static struct module *load_module(void __user *umod,
 	    (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
 	    (mod->num_unused_syms && !unusedcrcindex) ||
 	    (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
-		printk(KERN_WARNING "%s: No versions for exported symbols."
-		       " Tainting kernel.\n", mod->name);
-		add_taint_module(mod, TAINT_FORCED_MODULE);
+		printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name);
+		err = try_to_force_load(mod, "nocrc");
+		if (err)
+			goto cleanup;
 	}
 #endif
 	markersindex = find_sec(hdr, sechdrs, secstrings, "__markers");
@@ -2185,6 +2227,8 @@ sys_init_module(void __user *umod,
 		mod->state = MODULE_STATE_GOING;
 		synchronize_sched();
 		module_put(mod);
+		blocking_notifier_call_chain(&module_notify_list,
+					     MODULE_STATE_GOING, mod);
 		mutex_lock(&module_mutex);
 		free_module(mod);
 		mutex_unlock(&module_mutex);