alac: Do bounds checking of lpc_order read from the bitstream

In lpc_prediction(), we write up to array element 'lpc_order' in
an array allocated to hold 'max_samples_per_frame' elements.

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
Signed-off-by: Martin Storsjö <martin@martin.st>
(cherry picked from commit 59480abce7)
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
This commit is contained in:
Martin Storsjö
2013-09-28 00:22:52 +03:00
committed by Luca Barbato
parent 2ff935a060
commit 78aa2ed620

View File

@@ -315,6 +315,9 @@ static int decode_element(AVCodecContext *avctx, void *data, int ch_index,
rice_history_mult[ch] = get_bits(&alac->gb, 3); rice_history_mult[ch] = get_bits(&alac->gb, 3);
lpc_order[ch] = get_bits(&alac->gb, 5); lpc_order[ch] = get_bits(&alac->gb, 5);
if (lpc_order[ch] >= alac->max_samples_per_frame)
return AVERROR_INVALIDDATA;
/* read the predictor table */ /* read the predictor table */
for (i = lpc_order[ch] - 1; i >= 0; i--) for (i = lpc_order[ch] - 1; i >= 0; i--)
lpc_coefs[ch][i] = get_sbits(&alac->gb, 16); lpc_coefs[ch][i] = get_sbits(&alac->gb, 16);