From d304d7e794d0fcb9eb8995cba5d48f78d592e4f8 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 29 Dec 2017 03:00:19 +0100 Subject: [PATCH] avcodec/exr: Check buf_size more completely Fixes: Out of heap array read Fixes: 4683/clusterfuzz-testcase-minimized-6152313673613312 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 903be5e4f66268273dc6e3c42a7fdeaab32066ef) Signed-off-by: Michael Niedermayer --- libavcodec/exr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavcodec/exr.c b/libavcodec/exr.c index 4dc975f4d1..694e18757f 100644 --- a/libavcodec/exr.c +++ b/libavcodec/exr.c @@ -847,7 +847,7 @@ static int decode_block(AVCodecContext *avctx, void *tdata, line_offset = AV_RL64(s->gb.buffer + jobnr * 8); // Check if the buffer has the required bytes needed from the offset - if (line_offset > buf_size - 8) + if (buf_size < 8 || line_offset > buf_size - 8) return AVERROR_INVALIDDATA; src = buf + line_offset + 8; @@ -856,7 +856,7 @@ static int decode_block(AVCodecContext *avctx, void *tdata, return AVERROR_INVALIDDATA; data_size = AV_RL32(src - 4); - if (data_size <= 0 || data_size > buf_size) + if (data_size <= 0 || data_size > buf_size - line_offset - 8) return AVERROR_INVALIDDATA; s->ysize = FFMIN(s->scan_lines_per_block, s->ymax - line + 1);