[FFmpeg-cvslog] avformat/icodec: Check nb_pal

[Michael Niedermayer]

ffmpeg | branch: release/5.0 | Michael Niedermayer <michael at niedermayer.cc> | Sat Sep 17 23:15:56 2022 +0200| [35d5d2a4b2b880fa114fcdd71963190d0d13e550] | committer: Michael Niedermayer

avformat/icodec: Check nb_pal

Fixes: signed integer overflow: 538976288 * 4 cannot be represented in type 'int'
Fixes: 50993/clusterfuzz-testcase-minimized-ffmpeg_dem_ICO_fuzzer-6690068904935424

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Peter Ross <pross at xvid.org>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit db73ae0dc114aa6fae08e69f977944f056a24995)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=35d5d2a4b2b880fa114fcdd71963190d0d13e550
---

 libavformat/icodec.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavformat/icodec.c b/libavformat/icodec.c
index 2e677c78f1..e533f70006 100644
--- a/libavformat/icodec.c
+++ b/libavformat/icodec.c
@@ -197,6 +197,9 @@ static int read_packet(AVFormatContext *s, AVPacket *pkt)
             AV_WL32(buf + 32, image->nb_pal);
         }
 
+        if (image->nb_pal > INT_MAX / 4 - 14 - 40)
+            return AVERROR_INVALIDDATA;
+
         AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4);
         AV_WL32(buf + 8, AV_RL32(buf + 8) / 2);
     }