SCSI: 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().  It fixes the problem in all of the scsi
drivers that need it.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 3 insertions, 4 deletions

diff --git a/drivers/scsi/ch.c b/drivers/scsi/ch.c
index 75c84d7b9ce..c4b938bc30d 100644
--- a/drivers/scsi/ch.c
+++ b/drivers/scsi/ch.c
@@ -910,9 +910,9 @@ static int ch_probe(struct device *dev)
         ch->minor = minor;
         sprintf(ch->name,"ch%d",ch->minor);
 
-        class_dev = device_create(ch_sysfs_class, dev,
-                                  MKDEV(SCSI_CHANGER_MAJOR,ch->minor),
-                                  "s%s", ch->name);
+        class_dev = device_create_drvdata(ch_sysfs_class, dev,
+                                          MKDEV(SCSI_CHANGER_MAJOR, ch->minor),
+                                          ch, "s%s", ch->name);
         if (IS_ERR(class_dev)) {
                 printk(KERN_WARNING "ch%d: device_create failed\n",
                        ch->minor);
@@ -926,7 +926,6 @@ static int ch_probe(struct device *dev)
         if (init)
                 ch_init_elem(ch);
 
-        dev_set_drvdata(dev, ch);
         sdev_printk(KERN_INFO, sd, "Attached scsi changer %s\n", ch->name);
 
         return 0;