gecko/media/libopus/padding.patch
Ralph Giles 65d654d29c Bug 817179 - Fix an issue with Opus padding larger than 16. r=tterribe
Packets with with more than 2^24 padding length bytes could
overflow the packet length calculation. This change avoids
the wrap around behaviour.
2012-11-30 15:02:23 -08:00

41 lines
1.3 KiB
Diff

From 9345aaa5ca1c2fb7d62981b2a538e0ce20612c38 Mon Sep 17 00:00:00 2001
From: Jean-Marc Valin <jmvalin@jmvalin.ca>
Date: Fri, 30 Nov 2012 17:36:36 -0500
Subject: [PATCH] Fixes an out-of-bounds read issue with the padding handling
code
This was reported by Juri Aedla and is limited to reading memory up
to about 60 kB beyond the compressed buffer. This can only be triggered
by a compressed packet more than about 16 MB long, so it's not a problem
for RTP. In theory, it *could* crash an Ogg decoder if the memory just after
the incoming packet is out-of-range.
---
src/opus_decoder.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/src/opus_decoder.c b/src/opus_decoder.c
index 167e4e4..0be6730 100644
--- a/src/opus_decoder.c
+++ b/src/opus_decoder.c
@@ -641,16 +641,14 @@ static int opus_packet_parse_impl(const unsigned char *data, opus_int32 len,
/* Padding flag is bit 6 */
if (ch&0x40)
{
- int padding=0;
int p;
do {
if (len<=0)
return OPUS_INVALID_PACKET;
p = *data++;
len--;
- padding += p==255 ? 254: p;
+ len -= p==255 ? 254: p;
} while (p==255);
- len -= padding;
}
if (len<0)
return OPUS_INVALID_PACKET;
--
1.7.11.7