From 36ea0ddc75ee83e6dd7f9dcdb82b8fcab08dd19e Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Mon, 11 May 2020 21:18:58 +0200
Subject: [PATCH] avcodec/iff: Test video_size being non zero

Fixes: Out of array access
Fixes: 20659/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_IFF_ILBM_fuzzer-5658548592967680
Fixes: 20659/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_IFF_ILBM_fuzzer-5723561177382912

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit a035fd88ae7341a05c01f3b393921933e4ea9665)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/iff.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavcodec/iff.c b/libavcodec/iff.c
index fcc5c67430..f094b4b548 100644
--- a/libavcodec/iff.c
+++ b/libavcodec/iff.c
@@ -440,6 +440,8 @@ static av_cold int decode_init(AVCodecContext *avctx)
 
     if (avctx->codec_tag == MKTAG('A', 'N', 'I', 'M')) {
         s->video_size = FFALIGN(avctx->width, 2) * avctx->height * s->bpp;
+        if (!s->video_size)
+            return AVERROR_INVALIDDATA;
         s->video[0] = av_calloc(FFALIGN(avctx->width, 2) * avctx->height, s->bpp);
         s->video[1] = av_calloc(FFALIGN(avctx->width, 2) * avctx->height, s->bpp);
         s->pal = av_calloc(256, sizeof(*s->pal));