Commit 4a9800c8 authored by 蒋家盛's avatar 蒋家盛 Committed by Kees Cook
Browse files

lkdtm/bugs: Check for the NULL pointer after calling kmalloc 



As the possible failure of the kmalloc(), the not_checked and checked
could be NULL pointer.
Therefore, it should be better to check it in order to avoid the
dereference of the NULL pointer.
Also, we need to kfree the 'not_checked' and 'checked' to avoid
the memory leak if fails.
And since it is just a test, it may directly return without error
number.

Fixes: ae2e1aad ("drivers/misc/lkdtm/bugs.c: add arithmetic overflow and array bounds checks")
Signed-off-by: default avatarJiasheng Jiang <jiasheng@iscas.ac.cn>
Acked-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220120092936.1874264-1-jiasheng@iscas.ac.cn
parent ce522ba9

drivers/misc/lkdtm/bugs.c

+5 −0
Original line number Diff line number Diff line
@@ -327,6 +327,11 @@ void lkdtm_ARRAY_BOUNDS(void) 


	not_checked = kmalloc(sizeof(*not_checked) * 2, GFP_KERNEL);

	checked = kmalloc(sizeof(*checked) * 2, GFP_KERNEL);

	if (!not_checked || !checked) {

		kfree(not_checked);

		kfree(checked);

		return;

	}



	pr_info("Array access within bounds ...\n");

	/* For both, touch all bytes in the actual member size. */