[PATCH 10/13] s390: fix race in device_create

From: Greg Kroah-Hartman
Date: Tue May 20 2008 - 18:41:28 EST


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@xxxxxxxx>
Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Cc: Cornelia Huck <cornelia.huck@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
drivers/s390/char/vmlogrdr.c | 9 ++++-----
1 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/s390/char/vmlogrdr.c b/drivers/s390/char/vmlogrdr.c
index e848734..2c2428c 100644
--- a/drivers/s390/char/vmlogrdr.c
+++ b/drivers/s390/char/vmlogrdr.c
@@ -762,10 +762,10 @@ static int vmlogrdr_register_device(struct vmlogrdr_priv_t *priv)
device_unregister(dev);
return ret;
}
- priv->class_device = device_create(vmlogrdr_class, dev,
- MKDEV(vmlogrdr_major,
- priv->minor_num),
- "%s", dev->bus_id);
+ priv->class_device = device_create_drvdata(vmlogrdr_class, dev,
+ MKDEV(vmlogrdr_major,
+ priv->minor_num),
+ priv, "%s", dev->bus_id);
if (IS_ERR(priv->class_device)) {
ret = PTR_ERR(priv->class_device);
priv->class_device=NULL;
@@ -773,7 +773,6 @@ static int vmlogrdr_register_device(struct vmlogrdr_priv_t *priv)
device_unregister(dev);
return ret;
}
- dev->driver_data = priv;
priv->device = dev;
return 0;
}
--
1.5.5.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/