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FFmpeg/libavformat/pjsdec.c
Clément Bœsch b84a7330af avformat/pjsdec: dont increase pointer when its already at the end in read_ts()
Fixes use of uninitialized memory
Fixes: msan_uninit-mem_7f91f2de7764_2649_PJS_capability_tester.pjs
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
2014-01-11 02:28:17 +01:00

139 lines
3.8 KiB
C

/*
* Copyright (c) 2012 Clément Bœsch
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* PJS (Phoenix Japanimation Society) subtitles format demuxer
*
* @see http://subs.com.ru/page.php?al=pjs
*/
#include "avformat.h"
#include "internal.h"
#include "subtitles.h"
typedef struct {
FFDemuxSubtitlesQueue q;
} PJSContext;
static int pjs_probe(AVProbeData *p)
{
char c;
int64_t start, end;
const unsigned char *ptr = p->buf;
if (sscanf(ptr, "%"SCNd64",%"SCNd64",%c", &start, &end, &c) == 3) {
size_t q1pos = strcspn(ptr, "\"");
size_t q2pos = q1pos + strcspn(ptr + q1pos + 1, "\"") + 1;
if (strcspn(ptr, "\r\n") > q2pos)
return AVPROBE_SCORE_MAX;
}
return 0;
}
static int64_t read_ts(char **line, int *duration)
{
int64_t start, end;
if (sscanf(*line, "%"SCNd64",%"SCNd64, &start, &end) == 2) {
*line += strcspn(*line, "\"");
*line += !!**line;
*duration = end - start;
return start;
}
return AV_NOPTS_VALUE;
}
static int pjs_read_header(AVFormatContext *s)
{
PJSContext *pjs = s->priv_data;
AVStream *st = avformat_new_stream(s, NULL);
int res = 0;
if (!st)
return AVERROR(ENOMEM);
avpriv_set_pts_info(st, 64, 1, 10);
st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
st->codec->codec_id = AV_CODEC_ID_PJS;
while (!url_feof(s->pb)) {
char line[4096];
char *p = line;
const int64_t pos = avio_tell(s->pb);
int len = ff_get_line(s->pb, line, sizeof(line));
int64_t pts_start;
int duration;
if (!len)
break;
line[strcspn(line, "\r\n")] = 0;
pts_start = read_ts(&p, &duration);
if (pts_start != AV_NOPTS_VALUE) {
AVPacket *sub;
p[strcspn(p, "\"")] = 0;
sub = ff_subtitles_queue_insert(&pjs->q, p, strlen(p), 0);
if (!sub)
return AVERROR(ENOMEM);
sub->pos = pos;
sub->pts = pts_start;
sub->duration = duration;
}
}
ff_subtitles_queue_finalize(&pjs->q);
return res;
}
static int pjs_read_packet(AVFormatContext *s, AVPacket *pkt)
{
PJSContext *pjs = s->priv_data;
return ff_subtitles_queue_read_packet(&pjs->q, pkt);
}
static int pjs_read_seek(AVFormatContext *s, int stream_index,
int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
{
PJSContext *pjs = s->priv_data;
return ff_subtitles_queue_seek(&pjs->q, s, stream_index,
min_ts, ts, max_ts, flags);
}
static int pjs_read_close(AVFormatContext *s)
{
PJSContext *pjs = s->priv_data;
ff_subtitles_queue_clean(&pjs->q);
return 0;
}
AVInputFormat ff_pjs_demuxer = {
.name = "pjs",
.long_name = NULL_IF_CONFIG_SMALL("PJS (Phoenix Japanimation Society) subtitles"),
.priv_data_size = sizeof(PJSContext),
.read_probe = pjs_probe,
.read_header = pjs_read_header,
.read_packet = pjs_read_packet,
.read_seek2 = pjs_read_seek,
.read_close = pjs_read_close,
.extensions = "pjs",
};