glibc/glibc-upstream-2.33-21.patch
Florian Weimer 83835daada Sync with Fedora f34 branch (glibc-2.33-11)
Fedora commit: 4f55bd2df5c705c99f21e1d35941843212b3e3a1

Related: #1945473
Resolves: #1945472
Resolves: #1915330
2021-05-07 13:55:45 +02:00

33 lines
1.2 KiB
Diff

commit 98bb18f52a7c576e6068f4b42dea5b24fa6fd81e
Author: Szabolcs Nagy <szabolcs.nagy@arm.com>
Date: Thu Feb 25 14:49:58 2021 +0000
malloc: Fix a realloc crash with heap tagging [BZ 27468]
_int_free must be called with a chunk that has its tag reset. This was
missing in a rare case that could crash when heap tagging is enabled:
when in a multi-threaded process the current arena runs out of memory
during realloc, but another arena still has space to finish the realloc
then _int_free was called without clearing the user allocation tags.
Fixes bug 27468.
Reviewed-by: DJ Delorie <dj@redhat.com>
(cherry picked from commit 42cc96066b22ba065db11096c78881a55e45def4)
diff --git a/malloc/malloc.c b/malloc/malloc.c
index 1f4bbd8edf8b9770..8f8f12c276812405 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -3446,7 +3446,9 @@ __libc_realloc (void *oldmem, size_t bytes)
newp = __libc_malloc (bytes);
if (newp != NULL)
{
- memcpy (newp, oldmem, oldsize - SIZE_SZ);
+ size_t sz = CHUNK_AVAILABLE_SIZE (oldp) - CHUNK_HDR_SZ;
+ memcpy (newp, oldmem, sz);
+ (void) TAG_REGION (chunk2rawmem (oldp), sz);
_int_free (ar_ptr, oldp, 0);
}
}