avcodec/alsdec: Avoid dereferencing context pointer in inner interleave loop

This makes the decoder faster

Improves/Fixes: Timeout (22sec -> 20sec)
Testcase: 17619/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALS_fuzzer-5078510820917248

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2019-09-25 20:31:50 +02:00
parent b2785cd3ac
commit 581a895c5c

View File

@ -1815,15 +1815,17 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
#define INTERLEAVE_OUTPUT(bps) \
{ \
int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \
int channels = avctx->channels; \
int32_t **raw_samples = ctx->raw_samples; \
shift = bps - ctx->avctx->bits_per_raw_sample; \
if (!ctx->cs_switch) { \
for (sample = 0; sample < ctx->cur_frame_length; sample++) \
for (c = 0; c < avctx->channels; c++) \
*dest++ = ctx->raw_samples[c][sample] * (1U << shift); \
for (c = 0; c < channels; c++) \
*dest++ = raw_samples[c][sample] * (1U << shift); \
} else { \
for (sample = 0; sample < ctx->cur_frame_length; sample++) \
for (c = 0; c < avctx->channels; c++) \
*dest++ = ctx->raw_samples[sconf->chan_pos[c]][sample] * (1U << shift); \
for (c = 0; c < channels; c++) \
*dest++ = raw_samples[sconf->chan_pos[c]][sample] * (1U << shift);\
} \
}