SOUND: fix race in device_create

There is a race from when a device is created with device_create() and
then the drvdata is set with a call to dev_set_drvdata() in which a
sysfs file could be open, yet the drvdata will be NULL, causing all
sorts of bad things to happen.

This patch fixes the problem by using the new function,
device_create_drvdata().

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 3 insertions, 5 deletions

diff --git a/sound/core/sound.c b/sound/core/sound.c
index 812f91b3de5b..6c8ab48c689a 100644
--- a/sound/core/sound.c
+++ b/sound/core/sound.c
@@ -259,8 +259,9 @@ int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
                 return minor;
         }
         snd_minors[minor] = preg;
-        preg->dev = device_create(sound_class, device, MKDEV(major, minor),
-                                  "%s", name);
+        preg->dev = device_create_drvdata(sound_class, device,
+                                          MKDEV(major, minor),
+                                          private_data, "%s", name);
         if (IS_ERR(preg->dev)) {
                 snd_minors[minor] = NULL;
                 mutex_unlock(&sound_mutex);
@@ -269,9 +270,6 @@ int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
                 return minor;
         }
 
-        if (preg->dev)
-                dev_set_drvdata(preg->dev, private_data);
-
         mutex_unlock(&sound_mutex);
         return 0;
 }