avcodec/aacps (fixed point): Fix multiple signed integer overflows

Fixes: runtime error: signed integer overflow: 1421978265 - -1810326882 cannot be represented in type 'int'
Fixes: 2527/clusterfuzz-testcase-minimized-5260915396050944

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 2017-07-09 15:19:18 +02:00
parent 15c41cb6ad
commit 80b9e40b6f

View File

@ -697,26 +697,17 @@ static void decorrelation(PSContext *ps, INTFLOAT (*out)[32][2], const INTFLOAT
for (i = 0; i < NR_PAR_BANDS[is34]; i++) {
for (n = n0; n < nL; n++) {
int decayed_peak;
int denom;
decayed_peak = (int)(((int64_t)peak_decay_factor * \
peak_decay_nrg[i] + 0x40000000) >> 31);
peak_decay_nrg[i] = FFMAX(decayed_peak, power[i][n]);
power_smooth[i] += (power[i][n] - power_smooth[i] + 2) >> 2;
peak_decay_diff_smooth[i] += (peak_decay_nrg[i] - power[i][n] - \
peak_decay_diff_smooth[i] + 2) >> 2;
denom = peak_decay_diff_smooth[i] + (peak_decay_diff_smooth[i] >> 1);
if (denom > power_smooth[i]) {
int p = power_smooth[i];
while (denom < 0x40000000) {
denom <<= 1;
p <<= 1;
}
transient_gain[i][n] = p / (denom >> 16);
}
else {
transient_gain[i][n] = 1 << 16;
}
power_smooth[i] += (power[i][n] + 2LL - power_smooth[i]) >> 2;
peak_decay_diff_smooth[i] += (peak_decay_nrg[i] + 2LL - power[i][n] - \
peak_decay_diff_smooth[i]) >> 2;
if (peak_decay_diff_smooth[i]) {
transient_gain[i][n] = FFMIN(power_smooth[i]*43691LL / peak_decay_diff_smooth[i], 1<<16);
} else
transient_gain[i][n] = 1 << 16;
}
}
#else