latmenc: validate extradata size.

Fixes potential out-of-bounds writes.
This is mostly possible when muxing ALS files where from
an extradata size of about 1050 put_bits would write data
outside the buffer.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
This commit is contained in:
Reimar Döffinger 2012-04-10 21:49:46 +02:00
parent 9540476ba1
commit d1a58afb95

View File

@ -27,6 +27,8 @@
#include "avformat.h"
#include "rawenc.h"
#define MAX_EXTRADATA_SIZE 1024
typedef struct {
AVClass *av_class;
int off;
@ -53,6 +55,10 @@ static int latm_decode_extradata(LATMContext *ctx, uint8_t *buf, int size)
{
MPEG4AudioConfig m4ac;
if (size > MAX_EXTRADATA_SIZE) {
av_log(ctx, AV_LOG_ERROR, "Extradata is larger than currently supported.\n");
return AVERROR_INVALIDDATA;
}
ctx->off = avpriv_mpeg4audio_get_config(&m4ac, buf, size * 8, 1);
if (ctx->off < 0)
return ctx->off;
@ -152,11 +158,11 @@ static int latm_write_packet(AVFormatContext *s, AVPacket *pkt)
if (pkt->size > 0x1fff)
goto too_large;
buf = av_malloc(pkt->size+1024);
buf = av_malloc(pkt->size+1024+MAX_EXTRADATA_SIZE);
if (!buf)
return AVERROR(ENOMEM);
init_put_bits(&bs, buf, pkt->size+1024);
init_put_bits(&bs, buf, pkt->size+1024+MAX_EXTRADATA_SIZE);
latm_write_frame_header(s, &bs);