Commit fdd4fa1c authored by Mateusz Nosek's avatar Mateusz Nosek Committed by Linus Torvalds
Browse files

mm/page_alloc.c: fix early params garbage value accesses 



Previously in '__init early_init_on_alloc' and '__init early_init_on_free'
the return values from 'kstrtobool' were not handled properly.  That
caused potential garbage value read from variable 'bool_result'.
Introduced patch fixes error handling.

Signed-off-by: default avatarMateusz Nosek <mateusznosek0@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Link: https://lkml.kernel.org/r/20200916214125.28271-1-mateusznosek0@gmail.com


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent cfb4a541

mm/page_alloc.c

+6 −6
Original line number Diff line number Diff line
@@ -156,16 +156,16 @@ static int __init early_init_on_alloc(char *buf) 
	int ret;

	bool bool_result;



	if (!buf)

		return -EINVAL;

	ret = kstrtobool(buf, &bool_result);

	if (ret)

		return ret;

	if (bool_result && page_poisoning_enabled())

		pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, will take precedence over init_on_alloc\n");

	if (bool_result)

		static_branch_enable(&init_on_alloc);

	else

		static_branch_disable(&init_on_alloc);

	return ret;

	return 0;

}

early_param("init_on_alloc", early_init_on_alloc);
@@ -174,16 +174,16 @@ static int __init early_init_on_free(char *buf) 
	int ret;

	bool bool_result;



	if (!buf)

		return -EINVAL;

	ret = kstrtobool(buf, &bool_result);

	if (ret)

		return ret;

	if (bool_result && page_poisoning_enabled())

		pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, will take precedence over init_on_free\n");

	if (bool_result)

		static_branch_enable(&init_on_free);

	else

		static_branch_disable(&init_on_free);

	return ret;

	return 0;

}

early_param("init_on_free", early_init_on_free);