Commit 3702b082 authored by Mark Hills's avatar Mark Hills Committed by Takashi Iwai
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ALSA: snd-usb-caiaq: Missing lock around use of buffer positions 



Fix a race which causes snd_pcm_update_hw_ptr_pos() to report a bug.

Signed-off-by: default avatarMark Hills <mark@pogo.org.uk>
Acked-by: default avatarDaniel Mack <daniel@caiaq.de>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent e8e0929d

sound/usb/caiaq/audio.c

+9 −3
Original line number Diff line number Diff line
@@ -269,16 +269,22 @@ snd_usb_caiaq_pcm_pointer(struct snd_pcm_substream *sub) 
{

	int index = sub->number;

	struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(sub);

	snd_pcm_uframes_t ptr;



	spin_lock(&dev->spinlock);



	if (dev->input_panic || dev->output_panic)

		return SNDRV_PCM_POS_XRUN;

		ptr = SNDRV_PCM_POS_XRUN;



	if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)

		return bytes_to_frames(sub->runtime,

		ptr = bytes_to_frames(sub->runtime,

					dev->audio_out_buf_pos[index]);

	else

		return bytes_to_frames(sub->runtime,

		ptr = bytes_to_frames(sub->runtime,

					dev->audio_in_buf_pos[index]);



	spin_unlock(&dev->spinlock);

	return ptr;

}



/* operators for both playback and capture */