From 9ea997395909907f569787d4ba5b96352ad31a80 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Wed, 23 Oct 2019 22:08:37 +0200 Subject: [PATCH] avcodec/xsubdec: fix overflow in alpha handling Fixes: left shift of 255 by 24 places cannot be represented in type 'int' Fixes: 18368/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_XSUB_fuzzer-5702665442426880 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/xsubdec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/xsubdec.c b/libavcodec/xsubdec.c index 93fd0f4d50..05c4a64ee5 100644 --- a/libavcodec/xsubdec.c +++ b/libavcodec/xsubdec.c @@ -130,7 +130,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, ((uint32_t *)sub->rects[0]->data[1])[i] |= 0xff000000; } else { for (i = 0; i < sub->rects[0]->nb_colors; i++) - ((uint32_t *)sub->rects[0]->data[1])[i] |= *buf++ << 24; + ((uint32_t *)sub->rects[0]->data[1])[i] |= (unsigned)*buf++ << 24; } #if FF_API_AVPICTURE