@@ -236,6 +236,7 @@ typedef struct ALSDecContext {
int **raw_mantissa; ///< decoded mantissa bits of the difference signal
unsigned char *larray; ///< buffer to store the output of masked lz decompression
int *nbits; ///< contains the number of bits to read for masked lz decompression for all samples
+ int highest_decoded_channel;
} ALSDecContext;
@@ -1678,6 +1679,7 @@ static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
memmove(ctx->raw_samples[c] - sconf->max_order,
ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
sizeof(*ctx->raw_samples[c]) * sconf->max_order);
+ ctx->highest_decoded_channel = c;
}
} else { // multi-channel coding
ALSBlockData bd = { 0 };
@@ -1746,6 +1748,8 @@ static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
if ((ret = decode_block(ctx, &bd)) < 0)
return ret;
+
+ ctx->highest_decoded_channel = FFMAX(ctx->highest_decoded_channel, c);
}
memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
@@ -1802,11 +1806,15 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
else
ctx->cur_frame_length = sconf->frame_length;
+ ctx->highest_decoded_channel = 0;
// decode the frame data
if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
av_log(ctx->avctx, AV_LOG_WARNING,
"Reading frame data failed. Skipping RA unit.\n");
+ if (ctx->highest_decoded_channel == 0)
+ return AVERROR_INVALIDDATA;
+
ctx->frame_id++;
/* get output buffer */
Fixes: Timeout (80sec -> 33sec) Fixes: 18668/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALS_fuzzer-5710836719157248 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavcodec/alsdec.c | 8 ++++++++ 1 file changed, 8 insertions(+)