summaryrefslogtreecommitdiff
path: root/malloc/hooks.c
diff options
context:
space:
mode:
authorWill Newton <will.newton@linaro.org>2013-10-10 13:17:13 +0100
committerWill Newton <will.newton@linaro.org>2013-10-30 14:46:02 -0700
commita56ee40b176d0a3f47f2a7eb75208f2e3763c9fd (patch)
tree02a3f3bc0c86de86bc89f185a8312b9b1a03670d /malloc/hooks.c
parentc6e4925d4069d38843c02994ffd284e8c87c8929 (diff)
downloadglibc-a56ee40b176d0a3f47f2a7eb75208f2e3763c9fd.tar.gz
malloc: Fix for infinite loop in memalign/posix_memalign.
A very large alignment argument passed to mealign/posix_memalign causes _int_memalign to enter an infinite loop. Limit the maximum alignment value to the maximum representable power of two to prevent this from happening. Changelog: 2013-10-30 Will Newton <will.newton@linaro.org> [BZ #16038] * malloc/hooks.c (memalign_check): Limit alignment to the maximum representable power of two. * malloc/malloc.c (__libc_memalign): Likewise. * malloc/tst-memalign.c (do_test): Add test for very large alignment values. * malloc/tst-posix_memalign.c (do_test): Likewise.
Diffstat (limited to 'malloc/hooks.c')
-rw-r--r--malloc/hooks.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/malloc/hooks.c b/malloc/hooks.c
index 3f663bb6b2..1dbe93f383 100644
--- a/malloc/hooks.c
+++ b/malloc/hooks.c
@@ -361,6 +361,14 @@ memalign_check(size_t alignment, size_t bytes, const void *caller)
if (alignment <= MALLOC_ALIGNMENT) return malloc_check(bytes, NULL);
if (alignment < MINSIZE) alignment = MINSIZE;
+ /* If the alignment is greater than SIZE_MAX / 2 + 1 it cannot be a
+ power of 2 and will cause overflow in the check below. */
+ if (alignment > SIZE_MAX / 2 + 1)
+ {
+ __set_errno (EINVAL);
+ return 0;
+ }
+
/* Check for overflow. */
if (bytes > SIZE_MAX - alignment - MINSIZE)
{