diff options
| author | Marios Titas | 2016-04-02 21:11:44 +0300 |
|---|---|---|
| committer | Michael Niedermayer | 2016-04-03 01:50:08 +0200 |
| commit | c1f9734f977f59bc0034096afbe8e43e40d93a5d (patch) | |
| tree | 04e9d365dd1d92a6c52565698a227b5b2d2d900f | |
| parent | ce87711df563a9d2d0537a062b86bb91b15ea1a0 (diff) | |
avfilter/src_movie: fix how we check for overflows with seek_point
Currently, if the movie source filter is used and a seek_point is
specified on a file that has a negative start time, ffmpeg will fail.
An easy way to reproduce this is as follows:
$ ffmpeg -vsync passthrough -filter_complex 'color=d=10,setpts=PTS-1/TB' test.mp4
$ ffmpeg -filter_complex 'movie=filename=test.mp4:seek_point=2' -f null -
The problem is caused by checking for int64_t overflow the wrong way.
In general, to check whether a + b overflows, it is not enough to do:
a > INT64_MAX - b
because b might be negative; the correct way is:
b > 0 && > a > INT64_MAX - b
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
| -rw-r--r-- | libavfilter/src_movie.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/libavfilter/src_movie.c b/libavfilter/src_movie.c index 82d2bcda10..eab24589dc 100644 --- a/libavfilter/src_movie.c +++ b/libavfilter/src_movie.c @@ -240,7 +240,7 @@ static av_cold int movie_common_init(AVFilterContext *ctx) timestamp = movie->seek_point; // add the stream start time, should it exist if (movie->format_ctx->start_time != AV_NOPTS_VALUE) { - if (timestamp > INT64_MAX - movie->format_ctx->start_time) { + if (timestamp > 0 && movie->format_ctx->start_time > INT64_MAX - timestamp) { av_log(ctx, AV_LOG_ERROR, "%s: seek value overflow with start_time:%"PRId64" seek_point:%"PRId64"\n", movie->file_name, movie->format_ctx->start_time, movie->seek_point); |