sysmalloc: Initialize previous size field of mmaped chunks

With different encodings of the header, the previous zero initialization
may be insufficient and produce an invalid encoding.

1 files changed, 5 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index e071097..997431e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2016-10-27  Florian Weimer  <fweimer@redhat.com>
+
+	* malloc/malloc.c (sysmalloc): Initialize previous size field of
+	mmaped chunks.
+
 2016-10-28  Florian Weimer  <fweimer@redhat.com>
 
 	* malloc/malloc.c (struct malloc_chunk): Rename prev_size, size