From 55e6c6b5feb7e2a9110fab1dc06ced23360b14e2 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sat, 3 Feb 2018 18:49:07 +0100 Subject: [PATCH] avcodec/scpr: Fix reading a pixel before the first Fixes: 5540/clusterfuzz-testcase-minimized-6122458273808384 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 0fb33a82890753233225c61863fff1fcc9d970d4) Signed-off-by: Michael Niedermayer --- libavcodec/scpr.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/libavcodec/scpr.c b/libavcodec/scpr.c index 78a6d5c0cd..694450abf0 100644 --- a/libavcodec/scpr.c +++ b/libavcodec/scpr.c @@ -679,6 +679,8 @@ static int decompress_p(AVCodecContext *avctx, return AVERROR_INVALIDDATA; if (bx == 0) { + if (by < 2) + return AVERROR_INVALIDDATA; z = backstep; } else { z = 0; @@ -708,6 +710,8 @@ static int decompress_p(AVCodecContext *avctx, return AVERROR_INVALIDDATA; if (bx == 0) { + if (by < 2) + return AVERROR_INVALIDDATA; z = backstep; } else { z = 0;