[FFmpeg-cvslog] tiff: do not overread the source buffer

[Luca Barbato]

ffmpeg | branch: release/0.10 | Luca Barbato <lu_zero at gentoo.org> | Mon Jun  3 04:53:02 2013 +0200| [96de1c5ed90b4defb4126d946061d4a23101b28c] | committer: Reinhard Tartler

tiff: do not overread the source buffer

At least 2 bytes from the source are read every loop.

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable at libav.org
(cherry picked from commit 9c2216976907336dfae0e8e38a4d70ca2465a92c)

Signed-off-by: Reinhard Tartler <siretart at tauware.de>

Conflicts:
	libavcodec/tiff.c

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=96de1c5ed90b4defb4126d946061d4a23101b28c
---

 libavcodec/tiff.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/libavcodec/tiff.c b/libavcodec/tiff.c
index a0db1f1..8a1db12 100644
--- a/libavcodec/tiff.c
+++ b/libavcodec/tiff.c
@@ -186,10 +186,13 @@ static int tiff_unpack_strip(TiffContext *s, uint8_t* dst, int stride, const uin
             break;
         case TIFF_PACKBITS:
             for(pixels = 0; pixels < width;){
+                if (ssrc + size - src < 2)
+                    return AVERROR_INVALIDDATA;
                 code = (int8_t)*src++;
                 if(code >= 0){
                     code++;
-                    if(pixels + code > width){
+                    if (pixels + code > width ||
+                        ssrc + size - src < code) {
                         av_log(s->avctx, AV_LOG_ERROR, "Copy went out of bounds\n");
                         return -1;
                     }