From 9fb677dd825618fd5e44b955e7f8d2ad7333ab3d Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sat, 13 May 2017 23:21:24 +0200 Subject: [PATCH] avcodec/webp: Fix signedness in prefix_code check Fixes: out of array read Fixes: 1557/clusterfuzz-testcase-minimized-6535013757616128 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 8c5cd1c9d33b4b287f85d42efb1aecfaee31de6c) Signed-off-by: Michael Niedermayer --- libavcodec/webp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/webp.c b/libavcodec/webp.c index e2769c0bf9..147d85f15b 100644 --- a/libavcodec/webp.c +++ b/libavcodec/webp.c @@ -694,7 +694,7 @@ static int decode_entropy_coded_image(WebPContext *s, enum ImageRole role, length = offset + get_bits(&s->gb, extra_bits) + 1; } prefix_code = huff_reader_get_symbol(&hg[HUFF_IDX_DIST], &s->gb); - if (prefix_code > 39) { + if (prefix_code > 39U) { av_log(s->avctx, AV_LOG_ERROR, "distance prefix code too large: %d\n", prefix_code); return AVERROR_INVALIDDATA;