From ec5663d0a796cb8acde8ad04ac4cc7e2be7d5173 Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Tue, 2 Mar 2021 11:20:29 +0100 Subject: [PATCH] avformat/dashdec: Ensure strings are zero-terminated MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit strncpy only ensures that one does not write beyond the end of the destination buffer; in case of truncation it does not zero-terminate the destination buffer. This makes using it the way it is now in the DASH demuxer dangerous. So use av_strlcpy instead. Also don't write anything if there is no id: The buffer has already been zeroed initially. The DASH testset from the Universität Klagenfurt contains samples with ids that are too long. E.g. http://ftp.itec.aau.at/datasets/DASHDataset2014/TearsOfSteel/1sec/TearsOfSteel_1s_simple_2014_05_09.mpd Reviewed-by: Steven Liu Signed-off-by: Andreas Rheinhardt --- libavformat/dashdec.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/libavformat/dashdec.c b/libavformat/dashdec.c index b82805c9ce..3a12aefa68 100644 --- a/libavformat/dashdec.c +++ b/libavformat/dashdec.c @@ -1042,7 +1042,8 @@ static int parse_manifest_representation(AVFormatContext *s, const char *url, if (rep->fragment_duration > 0 && !rep->fragment_timescale) rep->fragment_timescale = 1; rep->bandwidth = rep_bandwidth_val ? atoi(rep_bandwidth_val) : 0; - strncpy(rep->id, rep_id_val ? rep_id_val : "", sizeof(rep->id)); + if (rep_id_val) + av_strlcpy(rep->id, rep_id_val, sizeof(rep->id)); rep->framerate = av_make_q(0, 0); if (type == AVMEDIA_TYPE_VIDEO) { char *rep_framerate_val = xmlGetProp(representation_node, "frameRate");