| From 29a11774d8ebbafe8418b4a5ffb4cc1160b194a1 Mon Sep 17 00:00:00 2001 |
| From: Pascal Cuoq <cuoq@trust-in-soft.com> |
| Date: Sun, 15 May 2016 09:05:46 +0200 |
| Subject: [PATCH] Avoid relying on undefined behavior in CVE-2015-1283 fix. It |
| does not really work: https://godbolt.org/g/Zl8gdF |
| |
| --- |
| expat/lib/xmlparse.c | 6 ++++-- |
| 1 file changed, 4 insertions(+), 2 deletions(-) |
| |
| diff --git a/expat/lib/xmlparse.c b/expat/lib/xmlparse.c |
| index 13e080d..cdb12ef 100644 |
| --- a/expat/lib/xmlparse.c |
| +++ b/expat/lib/xmlparse.c |
| @@ -1693,7 +1693,8 @@ XML_GetBuffer(XML_Parser parser, int len) |
| } |
| |
| if (len > bufferLim - bufferEnd) { |
| - int neededSize = len + (int)(bufferEnd - bufferPtr); |
| + /* Do not invoke signed arithmetic overflow: */ |
| + int neededSize = (int) ((unsigned)len + (unsigned)(bufferEnd - bufferPtr)); |
| if (neededSize < 0) { |
| errorCode = XML_ERROR_NO_MEMORY; |
| return NULL; |
| @@ -1725,7 +1726,8 @@ XML_GetBuffer(XML_Parser parser, int len) |
| if (bufferSize == 0) |
| bufferSize = INIT_BUFFER_SIZE; |
| do { |
| - bufferSize *= 2; |
| + /* Do not invoke signed arithmetic overflow: */ |
| + bufferSize = (int) (2U * (unsigned) bufferSize); |
| } while (bufferSize < neededSize && bufferSize > 0); |
| if (bufferSize <= 0) { |
| errorCode = XML_ERROR_NO_MEMORY; |
| -- |
| 2.8.2 |
| |
