From 1bfc1aa004950c5ad527d823a08b8a19eef34eb0 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Wed, 24 Jan 2018 03:28:49 +0100 Subject: [PATCH] avcodec/mjpegdec: Fix integer overflow in DC dequantization Fixes: runtime error: signed integer overflow: -65535 * 65312 cannot be represented in type 'int' Fixes: 4900/clusterfuzz-testcase-minimized-5769019744321536 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/mjpegdec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c index e005dd0cd3..5055ee2826 100644 --- a/libavcodec/mjpegdec.c +++ b/libavcodec/mjpegdec.c @@ -715,7 +715,7 @@ static int decode_block(MJpegDecodeContext *s, int16_t *block, int component, av_log(s->avctx, AV_LOG_ERROR, "error dc\n"); return AVERROR_INVALIDDATA; } - val = val * quant_matrix[0] + s->last_dc[component]; + val = val * (unsigned)quant_matrix[0] + s->last_dc[component]; val = av_clip_int16(val); s->last_dc[component] = val; block[0] = val;