From 183fca09b08c56cbd8a27a80996170537f0c2a6c Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sun, 25 Oct 2020 00:23:12 +0200 Subject: [PATCH] avcodec/exr: skip bottom clearing loop when its outside the image Fixes: signed integer overflow: 1633771809 * 32960 cannot be represented in type 'int' Fixes: 26532/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_EXR_fuzzer-5613925708857344 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/exr.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/libavcodec/exr.c b/libavcodec/exr.c index ec1967ad0c..6e3e84d175 100644 --- a/libavcodec/exr.c +++ b/libavcodec/exr.c @@ -1821,10 +1821,12 @@ static int decode_frame(AVCodecContext *avctx, void *data, avctx->execute2(avctx, decode_block, s->thread_data, NULL, nb_blocks); // Zero out the end if ymax+1 is not h - ptr = picture->data[0] + ((s->ymax+1) * picture->linesize[0]); - for (y = s->ymax + 1; y < avctx->height; y++) { - memset(ptr, 0, out_line_size); - ptr += picture->linesize[0]; + if ((s->ymax+1) < avctx->height) { + ptr = picture->data[0] + ((s->ymax+1) * picture->linesize[0]); + for (y = s->ymax + 1; y < avctx->height; y++) { + memset(ptr, 0, out_line_size); + ptr += picture->linesize[0]; + } } picture->pict_type = AV_PICTURE_TYPE_I;