Commit 1e95a3e8 authored by Michael Niedermayer's avatar Michael Niedermayer

avcodec/apedec: Fix several integer overflows in predictor_update_filter() and do_apply_filter()

Fixes: negation of -2147483648 cannot be represented in type 'int'; cast to an unsigned type to negate this value to itself
Fixes: signed integer overflow: -14527961 - 2147483425 cannot be represented in type 'int'
Fixes: 16380/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APE_fuzzer-5645957131141120
Fixes: 16968/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APE_fuzzer-5716169901735936
Fixes: 17074/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APE_fuzzer-5198710497083392

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
parent f63cd196
...@@ -1121,7 +1121,7 @@ static av_always_inline int predictor_update_filter(APEPredictor *p, ...@@ -1121,7 +1121,7 @@ static av_always_inline int predictor_update_filter(APEPredictor *p,
p->buf[delayA] = p->lastA[filter]; p->buf[delayA] = p->lastA[filter];
p->buf[adaptA] = APESIGN(p->buf[delayA]); p->buf[adaptA] = APESIGN(p->buf[delayA]);
p->buf[delayA - 1] = p->buf[delayA] - p->buf[delayA - 1]; p->buf[delayA - 1] = p->buf[delayA] - (unsigned)p->buf[delayA - 1];
p->buf[adaptA - 1] = APESIGN(p->buf[delayA - 1]); p->buf[adaptA - 1] = APESIGN(p->buf[delayA - 1]);
predictionA = p->buf[delayA ] * p->coeffsA[filter][0] + predictionA = p->buf[delayA ] * p->coeffsA[filter][0] +
...@@ -1132,7 +1132,7 @@ static av_always_inline int predictor_update_filter(APEPredictor *p, ...@@ -1132,7 +1132,7 @@ static av_always_inline int predictor_update_filter(APEPredictor *p,
/* Apply a scaled first-order filter compression */ /* Apply a scaled first-order filter compression */
p->buf[delayB] = p->filterA[filter ^ 1] - ((int)(p->filterB[filter] * 31U) >> 5); p->buf[delayB] = p->filterA[filter ^ 1] - ((int)(p->filterB[filter] * 31U) >> 5);
p->buf[adaptB] = APESIGN(p->buf[delayB]); p->buf[adaptB] = APESIGN(p->buf[delayB]);
p->buf[delayB - 1] = p->buf[delayB] - p->buf[delayB - 1]; p->buf[delayB - 1] = p->buf[delayB] - (unsigned)p->buf[delayB - 1];
p->buf[adaptB - 1] = APESIGN(p->buf[delayB - 1]); p->buf[adaptB - 1] = APESIGN(p->buf[delayB - 1]);
p->filterB[filter] = p->filterA[filter ^ 1]; p->filterB[filter] = p->filterA[filter ^ 1];
...@@ -1282,7 +1282,7 @@ static void do_apply_filter(APEContext *ctx, int version, APEFilter *f, ...@@ -1282,7 +1282,7 @@ static void do_apply_filter(APEContext *ctx, int version, APEFilter *f,
/* Version 3.98 and later files */ /* Version 3.98 and later files */
/* Update the adaption coefficients */ /* Update the adaption coefficients */
absres = FFABS(res); absres = res < 0 ? -(unsigned)res : res;
if (absres) if (absres)
*f->adaptcoeffs = APESIGN(res) * *f->adaptcoeffs = APESIGN(res) *
(8 << ((absres > f->avg * 3) + (absres > f->avg * 4 / 3))); (8 << ((absres > f->avg * 3) + (absres > f->avg * 4 / 3)));
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment