From 3b3b1a29eb89ba93f91213cbebb332a2ac31fa8b Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 8 May 2018 12:55:26 -0700 Subject: mm: Use overflow helpers in kvmalloc() Instead of open-coded multiplication and bounds checking, use the new overflow helper. Additionally prepare for vmalloc() users to add array_size()-family helpers in the future. Signed-off-by: Kees Cook --- include/linux/mm.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'include/linux/mm.h') diff --git a/include/linux/mm.h b/include/linux/mm.h index 1ac1f06a4be6..7cb1c6a6bf82 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -25,6 +25,7 @@ #include #include #include +#include struct mempolicy; struct anon_vma; @@ -560,10 +561,12 @@ static inline void *kvzalloc(size_t size, gfp_t flags) static inline void *kvmalloc_array(size_t n, size_t size, gfp_t flags) { - if (size != 0 && n > SIZE_MAX / size) + size_t bytes; + + if (unlikely(check_mul_overflow(n, size, &bytes))) return NULL; - return kvmalloc(n * size, flags); + return kvmalloc(bytes, flags); } extern void kvfree(const void *addr); -- cgit v1.2.3