vorbisdec: Fix decoding bug with channel handling

Fixes Bug: #191
Chromium Bug: #101458
CVE-2011-3895

Signed-off-by: Reinhard Tartler <siretart@tauware.de>
This commit is contained in:
Reinhard Tartler 2012-01-05 21:40:18 +01:00
parent badb195d13
commit e6d527ff72

View File

@ -675,7 +675,7 @@ static int vorbis_parse_setup_hdr_residues(vorbis_context *vc)
res_setup->partition_size = get_bits(gb, 24) + 1;
/* Validations to prevent a buffer overflow later. */
if (res_setup->begin>res_setup->end ||
res_setup->end > vc->avccontext->channels * vc->blocksize[1] / 2 ||
res_setup->end > (res_setup->type == 2 ? vc->avccontext->channels : 1) * vc->blocksize[1] / 2 ||
(res_setup->end-res_setup->begin) / res_setup->partition_size > V_MAX_PARTITIONS) {
av_log(vc->avccontext, AV_LOG_ERROR,
"partition out of bounds: type, begin, end, size, blocksize: %"PRIu16", %"PRIu32", %"PRIu32", %u, %"PRIu32"\n",
@ -1478,6 +1478,7 @@ static int vorbis_parse_audio_packet(vorbis_context *vc)
uint8_t res_chan[255];
unsigned res_num = 0;
int retlen = 0;
int ch_left = vc->audio_channels;
if (get_bits1(gb)) {
av_log(vc->avccontext, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");
@ -1552,9 +1553,14 @@ static int vorbis_parse_audio_packet(vorbis_context *vc)
}
}
residue = &vc->residues[mapping->submap_residue[i]];
if (ch_left < ch) {
av_log(vc->avccontext, AV_LOG_ERROR, "Too many channels in vorbis_floor_decode.\n");
return -1;
}
vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, blocksize/2);
ch_res_ptr += ch * blocksize / 2;
ch_left -= ch;
}
// Inverse coupling