Commit ddaefe89 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'modules-for-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux 

Pull module updates from Jessica Yu:
 "Summary of modules changes for the 5.6 merge window:

   - Add "MS" (SHF_MERGE|SHF_STRINGS) section flags to __ksymtab_strings
     to indicate to the linker that it can perform string deduplication
     (i.e., duplicate strings are reduced to a single copy in the string
     table). This means any repeated namespace string would be merged to
     just one entry in __ksymtab_strings.

   - Various code cleanups and small fixes (fix small memleak in error
     path, improve moduleparam docs, silence rcu warnings, improve error
     logging)"

* tag 'modules-for-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module.h: Annotate mod_kallsyms with __rcu
  module: avoid setting info->name early in case we can fall back to info->mod->name
  modsign: print module name along with error message
  kernel/module: Fix memleak in module_add_modinfo_attrs()
  export.h: reduce __ksymtab_strings string duplication by using "MS" section flags
  moduleparam: fix kerneldoc
  modules: lockdep: Suppress suspicious RCU usage warning
parents c5951e7c 6080d608

include/asm-generic/export.h

+5 −3
Original line number Diff line number Diff line
@@ -27,9 +27,11 @@ 
.endm



/*

 * note on .section use: @progbits vs %progbits nastiness doesn't matter,

 * since we immediately emit into those sections anyway.

 * note on .section use: we specify progbits since usage of the "M" (SHF_MERGE)

 * section flag requires it. Use '%progbits' instead of '@progbits' since the

 * former apparently works on all arches according to the binutils source.

 */



.macro ___EXPORT_SYMBOL name,val,sec

#ifdef CONFIG_MODULES

	.section ___ksymtab\sec+\name,"a"
@@ -37,7 +39,7 @@ 
__ksymtab_\name:

	__put \val, __kstrtab_\name

	.previous

	.section __ksymtab_strings,"a"

	.section __ksymtab_strings,"aMS",%progbits,1

__kstrtab_\name:

	.asciz "\name"

	.previous

include/linux/export.h

+23 −10
Original line number Diff line number Diff line
@@ -82,16 +82,29 @@ struct kernel_symbol { 


#else



/* For every exported symbol, place a struct in the __ksymtab section */

/*

 * For every exported symbol, do the following:

 *

 * - If applicable, place a CRC entry in the __kcrctab section.

 * - Put the name of the symbol and namespace (empty string "" for none) in

 *   __ksymtab_strings.

 * - Place a struct kernel_symbol entry in the __ksymtab section.

 *

 * note on .section use: we specify progbits since usage of the "M" (SHF_MERGE)

 * section flag requires it. Use '%progbits' instead of '@progbits' since the

 * former apparently works on all arches according to the binutils source.

 */

#define ___EXPORT_SYMBOL(sym, sec, ns)						\

	extern typeof(sym) sym;							\

	extern const char __kstrtab_##sym[];					\

	extern const char __kstrtabns_##sym[];					\

	__CRC_SYMBOL(sym, sec);							\

	static const char __kstrtab_##sym[]				\

	__attribute__((section("__ksymtab_strings"), used, aligned(1)))	\

	= #sym;								\

	static const char __kstrtabns_##sym[]				\

	__attribute__((section("__ksymtab_strings"), used, aligned(1)))	\

	= ns;								\

	asm("	.section \"__ksymtab_strings\",\"aMS\",%progbits,1	\n"	\

	    "__kstrtab_" #sym ":					\n"	\

	    "	.asciz 	\"" #sym "\"					\n"	\

	    "__kstrtabns_" #sym ":					\n"	\

	    "	.asciz 	\"" ns "\"					\n"	\

	    "	.previous						\n");	\

	__KSYMTAB_ENTRY(sym, sec)



#endif

include/linux/module.h

+1 −1
Original line number Diff line number Diff line
@@ -429,7 +429,7 @@ struct module { 


#ifdef CONFIG_KALLSYMS

	/* Protected by RCU and/or module_mutex: use rcu_dereference() */

	struct mod_kallsyms *kallsyms;

	struct mod_kallsyms __rcu *kallsyms;

	struct mod_kallsyms core_kallsyms;



	/* Section attributes */

include/linux/moduleparam.h

+77 −5
Original line number Diff line number Diff line
@@ -128,6 +128,9 @@ struct kparam_array 


/**

 * module_param_unsafe - same as module_param but taints kernel

 * @name: the variable to alter, and exposed parameter name.

 * @type: the type of the parameter

 * @perm: visibility in sysfs.

 */

#define module_param_unsafe(name, type, perm)			\

	module_param_named_unsafe(name, name, type, perm)
@@ -150,6 +153,10 @@ struct kparam_array 


/**

 * module_param_named_unsafe - same as module_param_named but taints kernel

 * @name: a valid C identifier which is the parameter name.

 * @value: the actual lvalue to alter.

 * @type: the type of the parameter

 * @perm: visibility in sysfs.

 */

#define module_param_named_unsafe(name, value, type, perm)		\

	param_check_##type(name, &(value));				\
@@ -160,6 +167,7 @@ struct kparam_array 
 * module_param_cb - general callback for a module/cmdline parameter

 * @name: a valid C identifier which is the parameter name.

 * @ops: the set & get operations for this parameter.

 * @arg: args for @ops

 * @perm: visibility in sysfs.

 *

 * The ops can have NULL set or get functions.
@@ -171,36 +179,96 @@ struct kparam_array 
	__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1,    \

			    KERNEL_PARAM_FL_UNSAFE)



#define __level_param_cb(name, ops, arg, perm, level)			\

	__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level, 0)

/**

 * <level>_param_cb - general callback for a module/cmdline parameter

 *                    to be evaluated before certain initcall level

 * core_param_cb - general callback for a module/cmdline parameter

 *                 to be evaluated before core initcall level

 * @name: a valid C identifier which is the parameter name.

 * @ops: the set & get operations for this parameter.

 * @arg: args for @ops

 * @perm: visibility in sysfs.

 *

 * The ops can have NULL set or get functions.

 */

#define __level_param_cb(name, ops, arg, perm, level)			\

	__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level, 0)



#define core_param_cb(name, ops, arg, perm)		\

	__level_param_cb(name, ops, arg, perm, 1)



/**

 * postcore_param_cb - general callback for a module/cmdline parameter

 *                     to be evaluated before postcore initcall level

 * @name: a valid C identifier which is the parameter name.

 * @ops: the set & get operations for this parameter.

 * @arg: args for @ops

 * @perm: visibility in sysfs.

 *

 * The ops can have NULL set or get functions.

 */

#define postcore_param_cb(name, ops, arg, perm)		\

	__level_param_cb(name, ops, arg, perm, 2)



/**

 * arch_param_cb - general callback for a module/cmdline parameter

 *                 to be evaluated before arch initcall level

 * @name: a valid C identifier which is the parameter name.

 * @ops: the set & get operations for this parameter.

 * @arg: args for @ops

 * @perm: visibility in sysfs.

 *

 * The ops can have NULL set or get functions.

 */

#define arch_param_cb(name, ops, arg, perm)		\

	__level_param_cb(name, ops, arg, perm, 3)



/**

 * subsys_param_cb - general callback for a module/cmdline parameter

 *                   to be evaluated before subsys initcall level

 * @name: a valid C identifier which is the parameter name.

 * @ops: the set & get operations for this parameter.

 * @arg: args for @ops

 * @perm: visibility in sysfs.

 *

 * The ops can have NULL set or get functions.

 */

#define subsys_param_cb(name, ops, arg, perm)		\

	__level_param_cb(name, ops, arg, perm, 4)



/**

 * fs_param_cb - general callback for a module/cmdline parameter

 *               to be evaluated before fs initcall level

 * @name: a valid C identifier which is the parameter name.

 * @ops: the set & get operations for this parameter.

 * @arg: args for @ops

 * @perm: visibility in sysfs.

 *

 * The ops can have NULL set or get functions.

 */

#define fs_param_cb(name, ops, arg, perm)		\

	__level_param_cb(name, ops, arg, perm, 5)



/**

 * device_param_cb - general callback for a module/cmdline parameter

 *                   to be evaluated before device initcall level

 * @name: a valid C identifier which is the parameter name.

 * @ops: the set & get operations for this parameter.

 * @arg: args for @ops

 * @perm: visibility in sysfs.

 *

 * The ops can have NULL set or get functions.

 */

#define device_param_cb(name, ops, arg, perm)		\

	__level_param_cb(name, ops, arg, perm, 6)



/**

 * late_param_cb - general callback for a module/cmdline parameter

 *                 to be evaluated before late initcall level

 * @name: a valid C identifier which is the parameter name.

 * @ops: the set & get operations for this parameter.

 * @arg: args for @ops

 * @perm: visibility in sysfs.

 *

 * The ops can have NULL set or get functions.

 */

#define late_param_cb(name, ops, arg, perm)		\

	__level_param_cb(name, ops, arg, perm, 7)
@@ -263,6 +331,10 @@ static inline void kernel_param_unlock(struct module *mod) 


/**

 * core_param_unsafe - same as core_param but taints kernel

 * @name: the name of the cmdline and sysfs parameter (often the same as var)

 * @var: the variable

 * @type: the type of the parameter

 * @perm: visibility in sysfs

 */

#define core_param_unsafe(name, var, type, perm)		\

	param_check_##type(name, &(var));				\

kernel/module.c

+13 −9
Original line number Diff line number Diff line
@@ -214,7 +214,8 @@ static struct module *mod_find(unsigned long addr) 
{

	struct module *mod;



	list_for_each_entry_rcu(mod, &modules, list) {

	list_for_each_entry_rcu(mod, &modules, list,

				lockdep_is_held(&module_mutex)) {

		if (within_module(addr, mod))

			return mod;

	}
@@ -448,7 +449,8 @@ bool each_symbol_section(bool (*fn)(const struct symsearch *arr, 
	if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))

		return true;



	list_for_each_entry_rcu(mod, &modules, list) {

	list_for_each_entry_rcu(mod, &modules, list,

				lockdep_is_held(&module_mutex)) {

		struct symsearch arr[] = {

			{ mod->syms, mod->syms + mod->num_syms, mod->crcs,

			  NOT_GPL_ONLY, false },
@@ -616,7 +618,8 @@ static struct module *find_module_all(const char *name, size_t len, 


	module_assert_mutex_or_preempt();



	list_for_each_entry_rcu(mod, &modules, list) {

	list_for_each_entry_rcu(mod, &modules, list,

				lockdep_is_held(&module_mutex)) {

		if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)

			continue;

		if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
@@ -1781,6 +1784,8 @@ static int module_add_modinfo_attrs(struct module *mod) 
error_out:

	if (i > 0)

		module_remove_modinfo_attrs(mod, --i);

	else

		kfree(mod->modinfo_attrs);

	return error;

}
@@ -2834,7 +2839,7 @@ static int module_sig_check(struct load_info *info, int flags) 
		reason = "Loading of module with unavailable key";

	decide:

		if (is_module_sig_enforced()) {

			pr_notice("%s is rejected\n", reason);

			pr_notice("%s: %s is rejected\n", info->name, reason);

			return -EKEYREJECTED;

		}
@@ -3011,9 +3016,7 @@ static int setup_load_info(struct load_info *info, int flags) 


	/* Try to find a name early so we can log errors with a module name */

	info->index.info = find_sec(info, ".modinfo");

	if (!info->index.info)

		info->name = "(missing .modinfo section)";

	else

	if (info->index.info)

		info->name = get_modinfo(info, "name");



	/* Find internal symbols and strings. */
@@ -3028,14 +3031,15 @@ static int setup_load_info(struct load_info *info, int flags) 
	}



	if (info->index.sym == 0) {

		pr_warn("%s: module has no symbols (stripped?)\n", info->name);

		pr_warn("%s: module has no symbols (stripped?)\n",

			info->name ?: "(missing .modinfo section or name field)");

		return -ENOEXEC;

	}



	info->index.mod = find_sec(info, ".gnu.linkonce.this_module");

	if (!info->index.mod) {

		pr_warn("%s: No module found in object\n",

			info->name ?: "(missing .modinfo name field)");

			info->name ?: "(missing .modinfo section or name field)");

		return -ENOEXEC;

	}

	/* This is temporary: point mod into copy of data. */

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