ALSA: isight: fix isight_pcm_abort() crashes
Fix crashes in isight_pcm_abort() that happen when the driver tries to
access isight->pcm->runtime which does not exist when the device is not
open. Introduce a new field pcm_active to track this state.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Reported-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/firewire/isight.c b/sound/firewire/isight.c
index a6f19f5..0230605 100644
--- a/sound/firewire/isight.c
+++ b/sound/firewire/isight.c
@@ -56,6 +56,7 @@
struct iso_packets_buffer buffer;
struct fw_iso_resources resources;
struct fw_iso_context *context;
+ bool pcm_active;
bool pcm_running;
bool first_packet;
int packet_index;
@@ -131,10 +132,12 @@
{
unsigned long flags;
- snd_pcm_stream_lock_irqsave(isight->pcm, flags);
- if (snd_pcm_running(isight->pcm))
- snd_pcm_stop(isight->pcm, SNDRV_PCM_STATE_XRUN);
- snd_pcm_stream_unlock_irqrestore(isight->pcm, flags);
+ if (ACCESS_ONCE(isight->pcm_active)) {
+ snd_pcm_stream_lock_irqsave(isight->pcm, flags);
+ if (snd_pcm_running(isight->pcm))
+ snd_pcm_stop(isight->pcm, SNDRV_PCM_STATE_XRUN);
+ snd_pcm_stream_unlock_irqrestore(isight->pcm, flags);
+ }
}
static void isight_dropped_samples(struct isight *isight, unsigned int total)
@@ -295,8 +298,17 @@
static int isight_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *hw_params)
{
- return snd_pcm_lib_alloc_vmalloc_buffer(substream,
- params_buffer_bytes(hw_params));
+ struct isight *isight = substream->private_data;
+ int err;
+
+ err = snd_pcm_lib_alloc_vmalloc_buffer(substream,
+ params_buffer_bytes(hw_params));
+ if (err < 0)
+ return err;
+
+ ACCESS_ONCE(isight->pcm_active) = true;
+
+ return 0;
}
static void isight_stop_streaming(struct isight *isight)
@@ -322,6 +334,8 @@
{
struct isight *isight = substream->private_data;
+ ACCESS_ONCE(isight->pcm_active) = false;
+
mutex_lock(&isight->mutex);
isight_stop_streaming(isight);
mutex_unlock(&isight->mutex);