From b30c07cc2b9ee5bc52e1782eba9aa40e99085a7e Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 6 Sep 2019 10:46:38 +0200 Subject: [PATCH] avcodec/alac: Fix invalid shifts in 20/24 bps Fixes: left shift of negative value -256 Fixes: 16892/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALAC_fuzzer-4880802642395136 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/alac.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavcodec/alac.c b/libavcodec/alac.c index c606f2af0e..fbe427595e 100644 --- a/libavcodec/alac.c +++ b/libavcodec/alac.c @@ -397,13 +397,13 @@ static int decode_element(AVCodecContext *avctx, AVFrame *frame, int ch_index, case 20: { for (ch = 0; ch < channels; ch++) { for (i = 0; i < alac->nb_samples; i++) - alac->output_samples_buffer[ch][i] <<= 12; + alac->output_samples_buffer[ch][i] *= 1 << 12; }} break; case 24: { for (ch = 0; ch < channels; ch++) { for (i = 0; i < alac->nb_samples; i++) - alac->output_samples_buffer[ch][i] <<= 8; + alac->output_samples_buffer[ch][i] *= 1 << 8; }} break; }