[FFmpeg-cvslog] avcodec/mjpegdec: Check len in ff_mjpeg_decode_dht()

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Wed May 13 17:41:41 2015 +0200| [cf9ab119d02dd8a80b37df02007d488aae5a2b80] | committer: Michael Niedermayer

avcodec/mjpegdec: Check len in ff_mjpeg_decode_dht()

Fixes CID1239167

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=cf9ab119d02dd8a80b37df02007d488aae5a2b80
---

 libavcodec/mjpegdec.c |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index 2e019d9..b3dc246 100644
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -204,6 +204,11 @@ int ff_mjpeg_decode_dht(MJpegDecodeContext *s)
 
     len = get_bits(&s->gb, 16) - 2;
 
+    if (8*len > get_bits_left(&s->gb)) {
+        av_log(s->avctx, AV_LOG_ERROR, "dht: len %d is too large\n", len);
+        return AVERROR_INVALIDDATA;
+    }
+
     while (len > 0) {
         if (len < 17)
             return AVERROR_INVALIDDATA;