[FFmpeg-cvslog] avcodec/msrle: Check side data size before use

[Michael Niedermayer]

ffmpeg | branch: release/3.1 | Michael Niedermayer <michael at niedermayer.cc> | Sun Oct 30 15:12:12 2016 +0100| [d98d006eefb914170c87ee63fea4988f61c1ca4b] | committer: Michael Niedermayer

avcodec/msrle:  Check side data size before use

Fixes out of array read

Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit a6330119a099840c5279697cf80cb768df97a90a)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=d98d006eefb914170c87ee63fea4988f61c1ca4b
---

 libavcodec/msrle.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/libavcodec/msrle.c b/libavcodec/msrle.c
index c2f6242..adb55b1 100644
--- a/libavcodec/msrle.c
+++ b/libavcodec/msrle.c
@@ -99,11 +99,14 @@ static int msrle_decode_frame(AVCodecContext *avctx,
         return ret;
 
     if (avctx->bits_per_coded_sample > 1 && avctx->bits_per_coded_sample <= 8) {
-        const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
+        int size;
+        const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &size);
 
-        if (pal) {
+        if (pal && size == AVPALETTE_SIZE) {
             s->frame->palette_has_changed = 1;
             memcpy(s->pal, pal, AVPALETTE_SIZE);
+        } else if (pal) {
+            av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
         }
         /* make the palette available */
         memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE);