vfio/mdev: Add missing error handling to dev_set_name()

stable inclusion
category: feature
from stable-5.13-rc1
commit 18d73124
bugzilla: https://gitee.com/openeuler/kernel/issues/I4NR4D

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=18d731242d5c67c0783126c42d3f85870cec2df5

-------------------------------------------------

This can fail, and seems to be a popular target for syzkaller error
injection. Check the error return and unwind with put_device().

Fixes: 7b96953b ("vfio: Mediated device Core driver")
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKevin Tian <kevin.tian@intel.com>
Reviewed-by: NMax Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>
Message-Id: <9-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NXingang Wang <wangxingang5@huawei.com>
Reviewed-by: NXu Xiaoyang <xuxiaoyang2@huawei.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKevin Tian <kevin.tian@intel.com>
Reviewed-by: NMax Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NXingang Wang <wangxingang5@huawei.com>
Reviewed-by: NXu Xiaoyang <xuxiaoyang2@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/vfio/mdev/mdev_core.c

@@ -316,7 +316,10 @@ int mdev_device_create(struct kobject *kobj,
 	mdev->dev.parent  = dev;
 	mdev->dev.bus     = &mdev_bus_type;
 	mdev->dev.release = mdev_device_release;
-	dev_set_name(&mdev->dev, "%pUl", uuid);
+	ret = dev_set_name(&mdev->dev, "%pUl", uuid);
+	if (ret)
+		goto ops_create_fail;
+
 	mdev->dev.groups = parent->ops->mdev_attr_groups;
 	mdev->type_kobj = kobj;