From 18c808ffbed81ea580fe6ddd6524dd7bea3f8d0e Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Wed, 10 Jul 2019 23:02:36 +0200 Subject: [PATCH] avcodec/pngdec: Check that previous_picture has same w/h/format Fixes: out of array access Fixes: 15540/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APNG_fuzzer-5684905029140480 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Reviewed-by: Paul B Mahol Signed-off-by: Michael Niedermayer --- libavcodec/pngdec.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c index 5209e342db..bf5a5191cc 100644 --- a/libavcodec/pngdec.c +++ b/libavcodec/pngdec.c @@ -1391,6 +1391,9 @@ exit_loop: if (CONFIG_PNG_DECODER && avctx->codec_id != AV_CODEC_ID_APNG) handle_p_frame_png(s, p); else if (CONFIG_APNG_DECODER && + s->previous_picture.f->width == p->width && + s->previous_picture.f->height== p->height && + s->previous_picture.f->format== p->format && avctx->codec_id == AV_CODEC_ID_APNG && (ret = handle_p_frame_apng(avctx, s, p)) < 0) goto fail;