From 3c716682a8b69e6644a385a663aaf0e5dc808ae8 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 15 Jun 2017 23:41:46 +0200 Subject: [PATCH] avcodec/truemotion2: Move skip computation after checks Fixes: runtime error: signed integer overflow: 630067357 * 4 cannot be represented in type 'int' Fixes: 2233/clusterfuzz-testcase-minimized-5943031318446080 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/truemotion2.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavcodec/truemotion2.c b/libavcodec/truemotion2.c index e6ae05f1d5..a463a925fd 100644 --- a/libavcodec/truemotion2.c +++ b/libavcodec/truemotion2.c @@ -298,15 +298,15 @@ static int tm2_read_stream(TM2Context *ctx, const uint8_t *buf, int stream_id, i /* get stream length in dwords */ bytestream2_init(&gb, buf, buf_size); len = bytestream2_get_be32(&gb); - skip = len * 4 + 4; if (len == 0) return 4; - if (len >= INT_MAX / 4 - 1 || len < 0 || skip > buf_size) { + if (len >= INT_MAX / 4 - 1 || len < 0 || len * 4 + 4 > buf_size) { av_log(ctx->avctx, AV_LOG_ERROR, "Error, invalid stream size.\n"); return AVERROR_INVALIDDATA; } + skip = len * 4 + 4; toks = bytestream2_get_be32(&gb); if (toks & 1) {