From 73c20eb18e99f3061e644d2426528ffa7be07075 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 28 Jan 2020 18:35:43 +0100 Subject: [PATCH] avcodec/apedec: Fix integer overflows in predictor_decode_mono_3950() Fixes: signed integer overflow: -2147407150 + -1871606 cannot be represented in type 'int' Fixes: 18702/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APE_fuzzer-5679095417667584 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit eb64a5c6f94981e4a68ad65a6e445557e11c08fc) Signed-off-by: Michael Niedermayer --- libavcodec/apedec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavcodec/apedec.c b/libavcodec/apedec.c index 19678a3ef0..3f9a2ce656 100644 --- a/libavcodec/apedec.c +++ b/libavcodec/apedec.c @@ -1203,14 +1203,14 @@ static void predictor_decode_mono_3950(APEContext *ctx, int count) A = *decoded0; p->buf[YDELAYA] = currentA; - p->buf[YDELAYA - 1] = p->buf[YDELAYA] - p->buf[YDELAYA - 1]; + p->buf[YDELAYA - 1] = p->buf[YDELAYA] - (unsigned)p->buf[YDELAYA - 1]; predictionA = p->buf[YDELAYA ] * p->coeffsA[0][0] + p->buf[YDELAYA - 1] * p->coeffsA[0][1] + p->buf[YDELAYA - 2] * p->coeffsA[0][2] + p->buf[YDELAYA - 3] * p->coeffsA[0][3]; - currentA = A + (predictionA >> 10); + currentA = A + (unsigned)(predictionA >> 10); p->buf[YADAPTCOEFFSA] = APESIGN(p->buf[YDELAYA ]); p->buf[YADAPTCOEFFSA - 1] = APESIGN(p->buf[YDELAYA - 1]);