From e56d1a120324fa49a5367cbf22098c5c7eb23f91 Mon Sep 17 00:00:00 2001 From: Lukasz Marek Date: Sat, 26 Oct 2013 01:32:55 +0200 Subject: [PATCH] lavd/alsa: add stream validation Don't trust provided streams. Return with error when stream count is not 1 or provided stream is not an audio stream. Signed-off-by: Lukasz Marek --- libavdevice/alsa-audio-enc.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/libavdevice/alsa-audio-enc.c b/libavdevice/alsa-audio-enc.c index 5033a4894e..83e1d2f85f 100644 --- a/libavdevice/alsa-audio-enc.c +++ b/libavdevice/alsa-audio-enc.c @@ -47,12 +47,17 @@ static av_cold int audio_write_header(AVFormatContext *s1) { AlsaData *s = s1->priv_data; - AVStream *st; + AVStream *st = NULL; unsigned int sample_rate; enum AVCodecID codec_id; int res; + if (s1->nb_streams != 1 || s1->streams[0]->codec->codec_type != AVMEDIA_TYPE_AUDIO) { + av_log(s1, AV_LOG_ERROR, "Only a single audio stream is supported.\n"); + return AVERROR(EINVAL); + } st = s1->streams[0]; + sample_rate = st->codec->sample_rate; codec_id = st->codec->codec_id; res = ff_alsa_open(s1, SND_PCM_STREAM_PLAYBACK, &sample_rate,