From e3f656f2dea6ef6e2a14e72931f3d6f205f732c8 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 25 May 2018 22:22:27 +0200 Subject: [PATCH] avcodec/ac3dec: Fix null pointer dereference in ac3_decode_frame() Fixes: index 8 out of bounds for type 'uint8_t *[8]' Fixes: 7273/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_EAC3_fuzzer-6296497667702784 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/ac3dec.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c index 1d3180b935..317b2bd800 100644 --- a/libavcodec/ac3dec.c +++ b/libavcodec/ac3dec.c @@ -1738,7 +1738,9 @@ dependent_frame: for (ch = 0; ch < avctx->channels; ch++) { int map = extended_channel_map[ch]; - memcpy((SHORTFLOAT *)frame->data[ch], s->output_buffer[map], + av_assert0(ch>=AV_NUM_DATA_POINTERS || frame->extended_data[ch] == frame->data[ch]); + memcpy((SHORTFLOAT *)frame->extended_data[ch], + s->output_buffer[map], s->num_blocks * AC3_BLOCK_SIZE * sizeof(SHORTFLOAT)); }