avcodec/tta: Fix integer overflow in prediction

Fixes: signed integer overflow: -395281576 + -1827578048 cannot be represented in type 'int'
Fixes: 16038/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TTA_fuzzer-5646109705240576

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 2019-08-11 20:56:44 +02:00
parent dea2591d4f
commit 7e9aecc9f3

View File

@ -227,7 +227,7 @@ static int tta_decode_frame(AVCodecContext *avctx, void *data,
GetBitContext gb;
int i, ret;
int cur_chan = 0, framelen = s->frame_length;
int32_t *p;
uint32_t *p;
if (avctx->err_recognition & AV_EF_CRCCHECK) {
if (buf_size < 4 ||
@ -261,7 +261,7 @@ static int tta_decode_frame(AVCodecContext *avctx, void *data,
}
i = 0;
for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) {
for (p = s->decode_buffer; (int32_t*)p < s->decode_buffer + (framelen * s->channels); p++) {
int32_t *predictor = &s->ch_ctx[cur_chan].predictor;
TTAFilter *filter = &s->ch_ctx[cur_chan].filter;
TTARice *rice = &s->ch_ctx[cur_chan].rice;
@ -334,7 +334,7 @@ static int tta_decode_frame(AVCodecContext *avctx, void *data,
// decorrelate in case of multiple channels
if (s->channels > 1) {
int32_t *r = p - 1;
for (*p += *r / 2; r > p - s->channels; r--)
for (*p += *r / 2; r > (int32_t*)p - s->channels; r--)
*r = *(r + 1) - *r;
}
cur_chan = 0;
@ -358,13 +358,13 @@ static int tta_decode_frame(AVCodecContext *avctx, void *data,
switch (s->bps) {
case 1: {
uint8_t *samples = (uint8_t *)frame->data[0];
for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++)
for (p = s->decode_buffer; (int32_t*)p < s->decode_buffer + (framelen * s->channels); p++)
*samples++ = *p + 0x80;
break;
}
case 2: {
int16_t *samples = (int16_t *)frame->data[0];
for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++)
for (p = s->decode_buffer; (int32_t*)p < s->decode_buffer + (framelen * s->channels); p++)
*samples++ = *p;
break;
}