diff options
| author | Takashi Iwai <tiwai@suse.de> | 2012-10-16 13:05:59 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2012-10-30 11:07:10 +0100 |
| commit | a0830dbd4e42b38aefdf3fb61ba5019a1a99ea85 (patch) | |
| tree | 4dc74b708a07b56d12ed72a34d0a2e0cb8c8b9d4 /sound/core/pcm_native.c | |
| parent | 888ea7d5ac6815ba16b3b3a20f665a92c7af6724 (diff) | |
ALSA: Add a reference counter to card instance
For more strict protection for wild disconnections, a refcount is
introduced to the card instance, and let it up/down when an object is
referred via snd_lookup_*() in the open ops.
The free-after-last-close check is also changed to check this refcount
instead of the empty list, too.
Reported-by: Matthieu CASTET <matthieu.castet@parrot.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/core/pcm_native.c')
| -rw-r--r-- | sound/core/pcm_native.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index 8753c89f3290..48c6a70ad69e 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -1642,6 +1642,7 @@ static int snd_pcm_link(struct snd_pcm_substream *substream, int fd) write_unlock_irq(&snd_pcm_link_rwlock); up_write(&snd_pcm_link_rwsem); _nolock: + snd_card_unref(substream1->pcm->card); fput_light(file, fput_needed); if (res < 0) kfree(group); @@ -2116,7 +2117,9 @@ static int snd_pcm_playback_open(struct inode *inode, struct file *file) return err; pcm = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_PCM_PLAYBACK); - return snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK); + err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK); + snd_card_unref(pcm->card); + return err; } static int snd_pcm_capture_open(struct inode *inode, struct file *file) @@ -2127,7 +2130,9 @@ static int snd_pcm_capture_open(struct inode *inode, struct file *file) return err; pcm = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_PCM_CAPTURE); - return snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE); + err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE); + snd_card_unref(pcm->card); + return err; } static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream) |