[FFmpeg-devel] [PATCH 01/15] avcodec/xsubdec: Check parse_timecode()
Michael Niedermayer
michael at niedermayer.cc
Fri Jul 5 03:21:42 EEST 2024
Fixes: CID1604490 Overflowed constant
Sponsored-by: Sovereign Tech Fund
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
libavcodec/xsubdec.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/libavcodec/xsubdec.c b/libavcodec/xsubdec.c
index db7873593c8..6be4c18b0b5 100644
--- a/libavcodec/xsubdec.c
+++ b/libavcodec/xsubdec.c
@@ -60,6 +60,7 @@ static int decode_frame(AVCodecContext *avctx, AVSubtitle *sub,
int64_t packet_time = 0;
GetBitContext gb;
int has_alpha = avctx->codec_tag == MKTAG('D','X','S','A');
+ int64_t start_display_time, end_display_time;
// check that at least header fits
if (buf_size < 27 + 7 * 2 + 4 * (3 + has_alpha)) {
@@ -74,8 +75,14 @@ static int decode_frame(AVCodecContext *avctx, AVSubtitle *sub,
}
if (avpkt->pts != AV_NOPTS_VALUE)
packet_time = av_rescale_q(avpkt->pts, AV_TIME_BASE_Q, (AVRational){1, 1000});
- sub->start_display_time = parse_timecode(buf + 1, packet_time);
- sub->end_display_time = parse_timecode(buf + 14, packet_time);
+
+ sub->start_display_time = start_display_time = parse_timecode(buf + 1, packet_time);
+ sub->end_display_time = end_display_time = parse_timecode(buf + 14, packet_time);
+ if (sub->start_display_time != start_display_time ||
+ sub-> end_display_time != end_display_time) {
+ av_log(avctx, AV_LOG_ERROR, "time code not representable in 32bit\n");
+ return -1;
+ }
buf += 27;
// read header
--
2.45.2
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