From 4d932eb66b037acf63bef4ce9a975a6f28f0e99a Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Fri, 8 Nov 2019 20:40:46 +0100
Subject: [PATCH] avcodec/alac: Fix integer overflow in lpc_prediction() with
sign
Fixes: signed integer overflow: -2147483648 * -1 cannot be represented in type 'int'
Fixes: 18643/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALAC_fuzzer-5672182449700864
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 7686ba1f149a94c3bac235589de8aa8db92be4e5)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
libavcodec/alac.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libavcodec/alac.c b/libavcodec/alac.c
index 5c8230bea4..21a48d252a 100644
--- a/libavcodec/alac.c
+++ b/libavcodec/alac.c
@@ -227,7 +227,7 @@ static void lpc_prediction(int32_t *error_buffer, uint32_t *buffer_out,
val = d - pred[j];
sign = sign_only(val) * error_sign;
lpc_coefs[j] -= sign;
- val *= sign;
+ val *= (unsigned)sign;
error_val -= (val >> lpc_quant) * (j + 1);
}
}