From 4dc204ea3e3633d2c8bd89ac9796b47e87c25836 Mon Sep 17 00:00:00 2001 From: Marth64 Date: Wed, 26 Jun 2024 22:05:46 -0500 Subject: [PATCH] avformat/dvdvideodec: Fix duration logic with 1 chapter and validate chapter range Chapters and duration are calculated together in dvdvideo demuxer. Previous chapter calculation logic treated extraction of 1 chapter using chapter_start and chapter_end switches incorrectly, returning the duration of the entire title instead of just the segment. Fix the logic so that it calculates and returns the duration of the chapter segment instead. Additionally, validate that chapter_end exceeds chapter_start (except in the special case of 0). Signed-off-by: Marth64 --- libavformat/dvdvideodec.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/libavformat/dvdvideodec.c b/libavformat/dvdvideodec.c index 8326595e1b..e7132725b7 100644 --- a/libavformat/dvdvideodec.c +++ b/libavformat/dvdvideodec.c @@ -865,8 +865,7 @@ static int dvdvideo_chapters_setup_simple(AVFormatContext *s) int chapter_end = c->opt_chapter_end > 0 ? c->opt_chapter_end : c->play_state.pgc_nb_pg_est - 1; /* dvdnav_describe_title_chapters() describes PGs rather than PTTs, so validate our range */ - if (chapter_start == chapter_end || - c->play_state.pgc_nb_pg_est == 1 || + if (c->play_state.pgc_nb_pg_est == 1 || chapter_start > c->play_state.pgc_nb_pg_est || chapter_end > c->play_state.pgc_nb_pg_est) { @@ -878,8 +877,11 @@ static int dvdvideo_chapters_setup_simple(AVFormatContext *s) for (int i = chapter_start - 1; i < chapter_end; i++) { uint64_t time_effective = c->play_state.pgc_pg_times_est[i] - c->play_state.nav_pts; - if (!avpriv_new_chapter(s, i, DVDVIDEO_TIME_BASE_Q, time_prev, time_effective, NULL)) + if (chapter_start != chapter_end && + !avpriv_new_chapter(s, i, DVDVIDEO_TIME_BASE_Q, time_prev, time_effective, NULL)) { + return AVERROR(ENOMEM); + } time_prev = time_effective; total_duration = time_effective; @@ -1548,6 +1550,13 @@ static int dvdvideo_read_header(AVFormatContext *s) return 0; } + if (c->opt_chapter_end != 0 && c->opt_chapter_start > c->opt_chapter_end) { + av_log(s, AV_LOG_ERROR, "Chapter (PTT) range [%d, %d] is invalid\n", + c->opt_chapter_start, c->opt_chapter_end); + + return AVERROR(EINVAL); + } + if (c->opt_title == 0) { av_log(s, AV_LOG_INFO, "Defaulting to title #1. " "This is not always the main feature, validation suggested.\n");