Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell: "Minor fixes mainly, including a potential use-after-free on remove found by CONFIG_DEBUG_KOBJECT_RELEASE which may be theoretical" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: module: Fix mod->mkobj.kobj potentially freed too early kernel/params.c: use scnprintf() instead of sprintf() kernel/module.c: use scnprintf() instead of sprintf() module/lsm: Have apparmor module parameters work with no args module: Add NOARG flag for ops with param_set_bool_enable_only() set function module: Add flag to allow mod params to have no arguments modules: add support for soft module dependencies scripts/mod/modpost.c: permit '.cranges' secton for sh64 architecture. module: fix sprintf format specifier in param_get_byte()

Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module updates from Rusty Russell: "Minor fixes mainly, including a potential use-after-free on remove found by CONFIG_DEBUG_KOBJECT_RELEASE which may be theoretical" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: module: Fix mod->mkobj.kobj potentially freed too early kernel/params.c: use scnprintf() instead of sprintf() kernel/module.c: use scnprintf() instead of sprintf() module/lsm: Have apparmor module parameters work with no args module: Add NOARG flag for ops with param_set_bool_enable_only() set function module: Add flag to allow mod params to have no arguments modules: add support for soft module dependencies scripts/mod/modpost.c: permit '.cranges' secton for sh64 architecture. module: fix sprintf format specifier in param_get_byte()
Linus Torvalds
2 parents 27703bb4a6 942e443127
Showing 6 changed files Side-by-side Diff
include/linux/module.h
include/linux/moduleparam.h
kernel/module.c
kernel/params.c
scripts/mod/modpost.c
security/apparmor/lsm.c
@@ -42,6 +42,7 @@
 	struct module *mod;
 	struct kobject *drivers_dir;
 	struct module_param_attrs *mp;
+	struct completion *kobj_completion;
 };
  
 struct module_attribute {
@@ -96,6 +97,11 @@
  
 /* For userspace: you can also call me... */
 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
+
+/* Soft module dependencies. See man modprobe.d for details.
+ * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz")
+ */
+#define MODULE_SOFTDEP(_softdep) MODULE_INFO(softdep, _softdep)
  
 /*
  * The following license idents are currently accepted as indicating free
@@ -36,7 +36,18 @@
  
 struct kernel_param;
  
+/*
+ * Flags available for kernel_param_ops
+ *
+ * NOARG - the parameter allows for no argument (foo instead of foo=1)
+ */
+enum {
+	KERNEL_PARAM_FL_NOARG = (1 << 0)
+};
+
 struct kernel_param_ops {
+	/* How the ops should behave */
+	unsigned int flags;
 	/* Returns 0, or -errno.  arg is in kp->arg. */
 	int (*set)(const char *val, const struct kernel_param *kp);
 	/* Returns length written or -errno.  Buffer is 4k (ie. be short!) */
@@ -187,7 +198,7 @@
 /* Obsolete - use module_param_cb() */
 #define module_param_call(name, set, get, arg, perm)			\
 	static struct kernel_param_ops __param_ops_##name =		\
-		 { (void *)set, (void *)get };				\
+		{ 0, (void *)set, (void *)get };			\
 	__module_param_call(MODULE_PARAM_PREFIX,			\
 			    name, &__param_ops_##name, arg,		\
 			    (perm) + sizeof(__check_old_set_param(set))*0, -1)
@@ -136,6 +136,7 @@
 }
  
 static const struct kernel_param_ops param_ops_bool_enable_only = {
+	.flags = KERNEL_PARAM_FL_NOARG,
 	.set = param_set_bool_enable_only,
 	.get = param_get_bool,
 };
@@ -603,7 +604,7 @@
 static ssize_t show_modinfo_##field(struct module_attribute *mattr,   \
 			struct module_kobject *mk, char *buffer)      \
 {                                                                     \
-	return sprintf(buffer, "%s\n", mk->mod->field);               \
+	return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field);  \
 }                                                                     \
 static int modinfo_##field##_exists(struct module *mod)               \
 {                                                                     \
@@ -1611,6 +1612,14 @@
 	kfree(mod->modinfo_attrs);
 }
  
+static void mod_kobject_put(struct module *mod)
+{
+	DECLARE_COMPLETION_ONSTACK(c);
+	mod->mkobj.kobj_completion = &c;
+	kobject_put(&mod->mkobj.kobj);
+	wait_for_completion(&c);
+}
+
 static int mod_sysfs_init(struct module *mod)
 {
 	int err;
@@ -1638,7 +1647,7 @@
 	err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
 				   "%s", mod->name);
 	if (err)
-		kobject_put(&mod->mkobj.kobj);
+		mod_kobject_put(mod);
  
 	/* delay uevent until full sysfs population */
 out:
@@ -1682,7 +1691,7 @@
 out_unreg_holders:
 	kobject_put(mod->holders_dir);
 out_unreg:
-	kobject_put(&mod->mkobj.kobj);
+	mod_kobject_put(mod);
 out:
 	return err;
 }
@@ -1691,7 +1700,7 @@
 {
 	remove_notes_attrs(mod);
 	remove_sect_attrs(mod);
-	kobject_put(&mod->mkobj.kobj);
+	mod_kobject_put(mod);
 }
  
 #else /* !CONFIG_SYSFS */
@@ -103,8 +103,8 @@
 			    || params[i].level > max_level)
 				return 0;
 			/* No one handled NULL, so do it here. */
-			if (!val && params[i].ops->set != param_set_bool
-			    && params[i].ops->set != param_set_bint)
+			if (!val &&
+			    !(params[i].ops->flags & KERNEL_PARAM_FL_NOARG))
 				return -EINVAL;
 			pr_debug("handling %s with %p\n", param,
 				params[i].ops->set);
@@ -241,7 +241,8 @@
 	}								\
 	int param_get_##name(char *buffer, const struct kernel_param *kp) \
 	{								\
-		return sprintf(buffer, format, *((type *)kp->arg));	\
+		return scnprintf(buffer, PAGE_SIZE, format,		\
+				*((type *)kp->arg));			\
 	}								\
 	struct kernel_param_ops param_ops_##name = {			\
 		.set = param_set_##name,				\
@@ -252,7 +253,7 @@
 	EXPORT_SYMBOL(param_ops_##name)
  
  
-STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
+STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", unsigned long, strict_strtoul);
 STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
 STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
 STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
@@ -285,7 +286,7 @@
  
 int param_get_charp(char *buffer, const struct kernel_param *kp)
 {
-	return sprintf(buffer, "%s", *((char **)kp->arg));
+	return scnprintf(buffer, PAGE_SIZE, "%s", *((char **)kp->arg));
 }
 EXPORT_SYMBOL(param_get_charp);
  
@@ -320,6 +321,7 @@
 EXPORT_SYMBOL(param_get_bool);
  
 struct kernel_param_ops param_ops_bool = {
+	.flags = KERNEL_PARAM_FL_NOARG,
 	.set = param_set_bool,
 	.get = param_get_bool,
 };
@@ -370,6 +372,7 @@
 EXPORT_SYMBOL(param_set_bint);
  
 struct kernel_param_ops param_ops_bint = {
+	.flags = KERNEL_PARAM_FL_NOARG,
 	.set = param_set_bint,
 	.get = param_get_int,
 };
@@ -827,7 +830,7 @@
 	struct module_version_attribute *vattr =
 		container_of(mattr, struct module_version_attribute, mattr);
  
-	return sprintf(buf, "%s\n", vattr->version);
+	return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
 }
  
 extern const struct module_version_attribute *__start___modver[];
  
@@ -912,7 +915,14 @@
 struct kset *module_kset;
 int module_sysfs_initialized;
  
+static void module_kobj_release(struct kobject *kobj)
+{
+	struct module_kobject *mk = to_module_kobject(kobj);
+	complete(mk->kobj_completion);
+}
+
 struct kobj_type module_ktype = {
+	.release   =	module_kobj_release,
 	.sysfs_ops =	&module_sysfs_ops,
 };
  
@@ -821,6 +821,7 @@
 {
 	".comment*",
 	".debug*",
+	".cranges",		/* sh64 */
 	".zdebug*",		/* Compressed debug sections. */
 	".GCC-command-line",	/* mn10300 */
 	".GCC.command.line",	/* record-gcc-switches, non mn10300 */
@@ -666,6 +666,7 @@
 static int param_get_aabool(char *buffer, const struct kernel_param *kp);
 #define param_check_aabool param_check_bool
 static struct kernel_param_ops param_ops_aabool = {
+	.flags = KERNEL_PARAM_FL_NOARG,
 	.set = param_set_aabool,
 	.get = param_get_aabool
 };
@@ -682,6 +683,7 @@
 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
 #define param_check_aalockpolicy param_check_bool
 static struct kernel_param_ops param_ops_aalockpolicy = {
+	.flags = KERNEL_PARAM_FL_NOARG,
 	.set = param_set_aalockpolicy,
 	.get = param_get_aalockpolicy
 };
...	...	@@ -42,6 +42,7 @@
42	42	struct module *mod;
43	43	struct kobject *drivers_dir;
44	44	struct module_param_attrs *mp;
	45	+ struct completion *kobj_completion;
45	46	};
46	47
47	48	struct module_attribute {
...	...	@@ -96,6 +97,11 @@
96	97
97	98	/* For userspace: you can also call me... */
98	99	#define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
	100	+
	101	+/* Soft module dependencies. See man modprobe.d for details.
	102	+ * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz")
	103	+ */
	104	+#define MODULE_SOFTDEP(_softdep) MODULE_INFO(softdep, _softdep)
99	105
100	106	/*
101	107	* The following license idents are currently accepted as indicating free
...	...	@@ -36,7 +36,18 @@
36	36
37	37	struct kernel_param;
38	38
	39	+/*
	40	+ * Flags available for kernel_param_ops
	41	+ *
	42	+ * NOARG - the parameter allows for no argument (foo instead of foo=1)
	43	+ */
	44	+enum {
	45	+ KERNEL_PARAM_FL_NOARG = (1 << 0)
	46	+};
	47	+
39	48	struct kernel_param_ops {
	49	+ /* How the ops should behave */
	50	+ unsigned int flags;
40	51	/* Returns 0, or -errno. arg is in kp->arg. */
41	52	int (set)(const char val, const struct kernel_param *kp);
42	53	/* Returns length written or -errno. Buffer is 4k (ie. be short!) */
...	...	@@ -187,7 +198,7 @@
187	198	/* Obsolete - use module_param_cb() */
188	199	#define module_param_call(name, set, get, arg, perm) \
189	200	static struct kernel_param_ops __param_ops_##name = \
190		- { (void )set, (void )get }; \
	201	+ { 0, (void )set, (void )get }; \
191	202	__module_param_call(MODULE_PARAM_PREFIX, \
192	203	name, &__param_ops_##name, arg, \
193	204	(perm) + sizeof(__check_old_set_param(set))*0, -1)
...	...	@@ -136,6 +136,7 @@
136	136	}
137	137
138	138	static const struct kernel_param_ops param_ops_bool_enable_only = {
	139	+ .flags = KERNEL_PARAM_FL_NOARG,
139	140	.set = param_set_bool_enable_only,
140	141	.get = param_get_bool,
141	142	};
...	...	@@ -603,7 +604,7 @@
603	604	static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
604	605	struct module_kobject mk, char buffer) \
605	606	{ \
606		- return sprintf(buffer, "%s\n", mk->mod->field); \
	607	+ return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
607	608	} \
608	609	static int modinfo_##field##_exists(struct module *mod) \
609	610	{ \
...	...	@@ -1611,6 +1612,14 @@
1611	1612	kfree(mod->modinfo_attrs);
1612	1613	}
1613	1614
	1615	+static void mod_kobject_put(struct module *mod)
	1616	+{
	1617	+ DECLARE_COMPLETION_ONSTACK(c);
	1618	+ mod->mkobj.kobj_completion = &c;
	1619	+ kobject_put(&mod->mkobj.kobj);
	1620	+ wait_for_completion(&c);
	1621	+}
	1622	+
1614	1623	static int mod_sysfs_init(struct module *mod)
1615	1624	{
1616	1625	int err;
...	...	@@ -1638,7 +1647,7 @@
1638	1647	err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1639	1648	"%s", mod->name);
1640	1649	if (err)
1641		- kobject_put(&mod->mkobj.kobj);
	1650	+ mod_kobject_put(mod);
1642	1651
1643	1652	/* delay uevent until full sysfs population */
1644	1653	out:
...	...	@@ -1682,7 +1691,7 @@
1682	1691	out_unreg_holders:
1683	1692	kobject_put(mod->holders_dir);
1684	1693	out_unreg:
1685		- kobject_put(&mod->mkobj.kobj);
	1694	+ mod_kobject_put(mod);
1686	1695	out:
1687	1696	return err;
1688	1697	}
...	...	@@ -1691,7 +1700,7 @@
1691	1700	{
1692	1701	remove_notes_attrs(mod);
1693	1702	remove_sect_attrs(mod);
1694		- kobject_put(&mod->mkobj.kobj);
	1703	+ mod_kobject_put(mod);
1695	1704	}
1696	1705
1697	1706	#else /* !CONFIG_SYSFS */
...	...	@@ -103,8 +103,8 @@
103	103	\|\| params[i].level > max_level)
104	104	return 0;
105	105	/* No one handled NULL, so do it here. */
106		- if (!val && params[i].ops->set != param_set_bool
107		- && params[i].ops->set != param_set_bint)
	106	+ if (!val &&
	107	+ !(params[i].ops->flags & KERNEL_PARAM_FL_NOARG))
108	108	return -EINVAL;
109	109	pr_debug("handling %s with %p\n", param,
110	110	params[i].ops->set);
...	...	@@ -241,7 +241,8 @@
241	241	} \
242	242	int param_get_##name(char buffer, const struct kernel_param kp) \
243	243	{ \
244		- return sprintf(buffer, format, ((type )kp->arg)); \
	244	+ return scnprintf(buffer, PAGE_SIZE, format, \
	245	+ ((type )kp->arg)); \
245	246	} \
246	247	struct kernel_param_ops param_ops_##name = { \
247	248	.set = param_set_##name, \
...	...	@@ -252,7 +253,7 @@
252	253	EXPORT_SYMBOL(param_ops_##name)
253	254
254	255
255		-STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
	256	+STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", unsigned long, strict_strtoul);
256	257	STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
257	258	STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
258	259	STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
...	...	@@ -285,7 +286,7 @@
285	286
286	287	int param_get_charp(char buffer, const struct kernel_param kp)
287	288	{
288		- return sprintf(buffer, "%s", ((char *)kp->arg));
	289	+ return scnprintf(buffer, PAGE_SIZE, "%s", ((char *)kp->arg));
289	290	}
290	291	EXPORT_SYMBOL(param_get_charp);
291	292
...	...	@@ -320,6 +321,7 @@
320	321	EXPORT_SYMBOL(param_get_bool);
321	322
322	323	struct kernel_param_ops param_ops_bool = {
	324	+ .flags = KERNEL_PARAM_FL_NOARG,
323	325	.set = param_set_bool,
324	326	.get = param_get_bool,
325	327	};
...	...	@@ -370,6 +372,7 @@
370	372	EXPORT_SYMBOL(param_set_bint);
371	373
372	374	struct kernel_param_ops param_ops_bint = {
	375	+ .flags = KERNEL_PARAM_FL_NOARG,
373	376	.set = param_set_bint,
374	377	.get = param_get_int,
375	378	};
...	...	@@ -827,7 +830,7 @@
827	830	struct module_version_attribute *vattr =
828	831	container_of(mattr, struct module_version_attribute, mattr);
829	832
830		- return sprintf(buf, "%s\n", vattr->version);
	833	+ return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
831	834	}
832	835
833	836	extern const struct module_version_attribute *__start___modver[];
834	837
...	...	@@ -912,7 +915,14 @@
912	915	struct kset *module_kset;
913	916	int module_sysfs_initialized;
914	917
	918	+static void module_kobj_release(struct kobject *kobj)
	919	+{
	920	+ struct module_kobject *mk = to_module_kobject(kobj);
	921	+ complete(mk->kobj_completion);
	922	+}
	923	+
915	924	struct kobj_type module_ktype = {
	925	+ .release = module_kobj_release,
916	926	.sysfs_ops = &module_sysfs_ops,
917	927	};
918	928
...	...	@@ -821,6 +821,7 @@
821	821	{
822	822	".comment*",
823	823	".debug*",
	824	+ ".cranges", /* sh64 */
824	825	".zdebug", / Compressed debug sections. */
825	826	".GCC-command-line", /* mn10300 */
826	827	".GCC.command.line", /* record-gcc-switches, non mn10300 */
...	...	@@ -666,6 +666,7 @@
666	666	static int param_get_aabool(char buffer, const struct kernel_param kp);
667	667	#define param_check_aabool param_check_bool
668	668	static struct kernel_param_ops param_ops_aabool = {
	669	+ .flags = KERNEL_PARAM_FL_NOARG,
669	670	.set = param_set_aabool,
670	671	.get = param_get_aabool
671	672	};
...	...	@@ -682,6 +683,7 @@
682	683	static int param_get_aalockpolicy(char buffer, const struct kernel_param kp);
683	684	#define param_check_aalockpolicy param_check_bool
684	685	static struct kernel_param_ops param_ops_aalockpolicy = {
	686	+ .flags = KERNEL_PARAM_FL_NOARG,
685	687	.set = param_set_aalockpolicy,
686	688	.get = param_get_aalockpolicy
687	689	};