IB: 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>
Reviewed-by: Roland Dreier <rolandd@cisco.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 6 insertions, 5 deletions

diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c
index cc1afa28c181..f806da184b51 100644
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -755,14 +755,15 @@ static void ib_uverbs_add_one(struct ib_device *device)
 	if (cdev_add(uverbs_dev->cdev, IB_UVERBS_BASE_DEV + uverbs_dev->devnum, 1))
 		goto err_cdev;
 
-	uverbs_dev->dev = device_create(uverbs_class, device->dma_device,
-					uverbs_dev->cdev->dev,
-					"uverbs%d", uverbs_dev->devnum);
+	uverbs_dev->dev = device_create_drvdata(uverbs_class,
+						device->dma_device,
+						uverbs_dev->cdev->dev,
+						uverbs_dev,
+						"uverbs%d",
+						uverbs_dev->devnum);
 	if (IS_ERR(uverbs_dev->dev))
 		goto err_cdev;
 
-	dev_set_drvdata(uverbs_dev->dev, uverbs_dev);
-
 	if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))
 		goto err_class;
 	if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))