avcodec/apedec: Fix multiple integer overflows in predictor_update_filter() Fixes: signed integer overflow: -829262115 + -1410750414 cannot be represented in type 'int' Fixes: 15251/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APE_fuzzer-5651742252859392 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
diff --git a/libavcodec/apedec.c b/libavcodec/apedec.c index eb31fd7..63335f5 100644 --- a/libavcodec/apedec.c +++ b/libavcodec/apedec.c
@@ -1142,7 +1142,7 @@ p->buf[delayB - 3] * p->coeffsB[filter][3] + p->buf[delayB - 4] * p->coeffsB[filter][4]; - p->lastA[filter] = decoded + ((predictionA + (predictionB >> 1)) >> 10); + p->lastA[filter] = decoded + ((int)((unsigned)predictionA + (predictionB >> 1)) >> 10); p->filterA[filter] = p->lastA[filter] + ((p->filterA[filter] * 31) >> 5); sign = APESIGN(decoded);