ALSA: use correct lock in snd_ctl_dev_disconnect()

commit d8009882e9f5e1a76986c741f071edd2ad760c97 upstream

The lock used in snd_ctl_dev_disconnect() should be card->ctl_files_rwlock
for protection of card->ctl_files entries, instead of card->controls_rwsem.

Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Cc: Chris Wedgwood <cw@f00f.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/sound/core/control.c b/sound/core/control.c
index 281b2e2ef0eac0bb4b87c4a475433a466459a98d..236bbb15b250d4fb44ba558cf1ff3c722107312f 100644 (file)
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -1427,12 +1427,12 @@ static int snd_ctl_dev_disconnect(struct snd_device *device)
        cardnum = card->number;
        snd_assert(cardnum >= 0 && cardnum < SNDRV_CARDS, return -ENXIO);
 
-       down_read(&card->controls_rwsem);
+       read_lock(&card->ctl_files_rwlock);
        list_for_each_entry(ctl, &card->ctl_files, list) {
                wake_up(&ctl->change_sleep);
                kill_fasync(&ctl->fasync, SIGIO, POLL_ERR);
        }
-       up_read(&card->controls_rwsem);
+       read_unlock(&card->ctl_files_rwlock);
 
        if ((err = snd_unregister_device(SNDRV_DEVICE_TYPE_CONTROL,
                                         card, -1)) < 0)