ALSA: aloop: Fix access to not-yet-ready substream via cable

[pandora-kernel.git] / sound / drivers / aloop.c

diff --git a/sound/drivers/aloop.c b/sound/drivers/aloop.c
index 3fa12d9..4e01b02 100644 (file)
--- a/sound/drivers/aloop.c
+++ b/sound/drivers/aloop.c
@@ -656,7 +656,9 @@ static void free_cable(struct snd_pcm_substream *substream)
                return;
        if (cable->streams[!substream->stream]) {
                /* other stream is still alive */
+               spin_lock_irq(&cable->lock);
                cable->streams[substream->stream] = NULL;
+               spin_unlock_irq(&cable->lock);
        } else {
                /* free the cable */
                loopback->cables[substream->number][dev] = NULL;
@@ -697,7 +699,6 @@ static int loopback_open(struct snd_pcm_substream *substream)
                loopback->cables[substream->number][dev] = cable;
        }
        dpcm->cable = cable;
-       cable->streams[substream->stream] = dpcm;
 
        snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 
@@ -729,6 +730,11 @@ static int loopback_open(struct snd_pcm_substream *substream)
                runtime->hw = loopback_pcm_hardware;
        else
                runtime->hw = cable->hw;
+
+       spin_lock_irq(&cable->lock);
+       cable->streams[substream->stream] = dpcm;
+       spin_unlock_irq(&cable->lock);
+
  unlock:
        if (err < 0) {
                free_cable(substream);