avcodec/apedec: Fix an integer overflow in predictor_update_filter()

Fixes: signed integer overflow: -2147483506 + -801380 cannot be represented in type 'int'
Fixes: 62164/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APE_fuzzer-6578985923117056

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2023-09-16 23:36:29 +02:00
parent bb9f8a1cb7
commit 515c0247a3
No known key found for this signature in database
GPG Key ID: B18E8928B3948D64

View File

@ -1220,7 +1220,7 @@ static av_always_inline int predictor_update_filter(APEPredictor64 *p,
if (interim_mode < 1) {
predictionA = (int32_t)predictionA;
predictionB = (int32_t)predictionB;
p->lastA[filter] = decoded + ((int32_t)(predictionA + (predictionB >> 1)) >> 10);
p->lastA[filter] = (int32_t)(decoded + (unsigned)((int32_t)(predictionA + (predictionB >> 1)) >> 10));
} else {
p->lastA[filter] = decoded + ((int64_t)((uint64_t)predictionA + (predictionB >> 1)) >> 10);
}