[FFmpeg-cvslog] avcodec/mjpegdec: Check escape sequence validity

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Wed Feb  4 20:13:18 2015 +0100| [afa92907f3c6a0c3bdad766ec8d938ee17ee1c9e] | committer: Michael Niedermayer

avcodec/mjpegdec: Check escape sequence validity

Fixes assertion failure
Fixes: asan_heap-oob_1c1a4ea_1242_cov_2274415971_TESTcmyk.jpg

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=afa92907f3c6a0c3bdad766ec8d938ee17ee1c9e
---

 libavcodec/mjpegdec.c |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index 054d936..c5769be 100644
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -1901,6 +1901,10 @@ int ff_mjpeg_find_marker(MJpegDecodeContext *s,
             put_bits(&pb, 8, x);
             if (x == 0xFF) {
                 x = src[b++];
+                if (x & 0x80) {
+                    av_log(s->avctx, AV_LOG_WARNING, "Invalid escape sequence\n");
+                    x &= 0x7f;
+                }
                 put_bits(&pb, 7, x);
                 bit_count--;
             }