From 9dcb4563847cb6e2a8112dca03d2684907f96313 Mon Sep 17 00:00:00 2001
From: Eric Rahm <erahm@mozilla.com>
Date: Fri, 10 Apr 2015 15:50:23 -0700
Subject: [PATCH] Bug 1140537 - Sanity check size calculations. r=peterv,
a=abillings
---
parser/expat/lib/xmlparse.c | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/parser/expat/lib/xmlparse.c b/parser/expat/lib/xmlparse.c
index 70acf1a..436b735 100644
--- a/parser/expat/lib/xmlparse.c
+++ b/parser/expat/lib/xmlparse.c
@@ -1651,6 +1651,12 @@ XML_ParseBuffer(XML_Parser parser, int len, int isFinal)
void * XMLCALL
XML_GetBuffer(XML_Parser parser, int len)
{
+/* BEGIN MOZILLA CHANGE (sanity check len) */
+ if (len < 0) {
+ errorCode = XML_ERROR_NO_MEMORY;
+ return NULL;
+ }
+/* END MOZILLA CHANGE */
switch (ps_parsing) {
case XML_SUSPENDED:
errorCode = XML_ERROR_SUSPENDED;
@@ -1662,8 +1668,13 @@ XML_GetBuffer(XML_Parser parser, int len)
}
if (len > bufferLim - bufferEnd) {
- /* FIXME avoid integer overflow */
int neededSize = len + (int)(bufferEnd - bufferPtr);
+/* BEGIN MOZILLA CHANGE (sanity check neededSize) */
+ if (neededSize < 0) {
+ errorCode = XML_ERROR_NO_MEMORY;
+ return NULL;
+ }
+/* END MOZILLA CHANGE */
#ifdef XML_CONTEXT_BYTES
int keep = (int)(bufferPtr - buffer);
@@ -1692,7 +1703,15 @@ XML_GetBuffer(XML_Parser parser, int len)
bufferSize = INIT_BUFFER_SIZE;
do {
bufferSize *= 2;
- } while (bufferSize < neededSize);
+/* BEGIN MOZILLA CHANGE (prevent infinite loop on overflow) */
+ } while (bufferSize < neededSize && bufferSize > 0);
+/* END MOZILLA CHANGE */
+/* BEGIN MOZILLA CHANGE (sanity check bufferSize) */
+ if (bufferSize <= 0) {
+ errorCode = XML_ERROR_NO_MEMORY;
+ return NULL;
+ }
+/* END MOZILLA CHANGE */
newBuf = (char *)MALLOC(bufferSize);
if (newBuf == 0) {
errorCode = XML_ERROR_NO_MEMORY;
--
2.2.1