avcodec/snowdec: Fix integer overflow in decode_subband_slice_buffered()

Fixes: runtime error: signed integer overflow: 267 * 8388608 cannot be represented in type 'int'
Fixes: 2743/clusterfuzz-testcase-minimized-5820652076400640

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 2017-08-28 00:30:33 +02:00
parent 2a83866c9f
commit 732f976456

View File

@ -140,7 +140,7 @@ static inline void decode_subband_slice_buffered(SnowContext *s, SubBand *b, sli
v = b->x_coeff[new_index].coeff;
x = b->x_coeff[new_index++].x;
while(x < w){
register int t= ( (v>>1)*qmul + qadd)>>QEXPSHIFT;
register int t= (int)( (v>>1)*(unsigned)qmul + qadd)>>QEXPSHIFT;
register int u= -(v&1);
line[x] = (t^u) - u;