SOUND: fix race in device_create
authorGreg Kroah-Hartman <gregkh@suse.de>
Sat, 17 May 2008 00:55:12 +0000 (17:55 -0700)
committerGreg Kroah-Hartman <gregkh@suse.de>
Tue, 20 May 2008 20:31:55 +0000 (13:31 -0700)
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>
sound/core/sound.c

index 812f91b3de5b88fca9259dece4ac4c4a5787a551..6c8ab48c689a6bb17a6b4dd490ba26c1204e32fd 100644 (file)
@@ -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;
 }