CVE ID:	CVE-2023-52837
Description:	In the Linux kernel, the following vulnerability has been resolved: nbd: fix uaf in nbd_open Commit 4af5f2e03013 ("nbd: use blk_mq_alloc_disk and blk_cleanup_disk") cleans up disk by blk_cleanup_disk() and it won't set disk->private_data as NULL as before. UAF may be triggered in nbd_open() if someone tries to open nbd device right after nbd_put() since nbd has been free in nbd_dev_remove(). Fix this by implementing ->free_disk and free private data in it.
Test IDs:	None available
Cross References:	Common Vulnerability Exposure (CVE) ID: CVE-2023-52837 https://git.kernel.org/stable/c/327462725b0f759f093788dfbcb2f1fd132f956b https://git.kernel.org/stable/c/327462725b0f759f093788dfbcb2f1fd132f956b https://git.kernel.org/stable/c/4e9b3ec84dc97909876641dad14e0a2300d6c2a3 https://git.kernel.org/stable/c/4e9b3ec84dc97909876641dad14e0a2300d6c2a3 https://git.kernel.org/stable/c/56bd7901b5e9dbc9112036ea615ebcba1565fafe https://git.kernel.org/stable/c/56bd7901b5e9dbc9112036ea615ebcba1565fafe https://git.kernel.org/stable/c/879947f4180bc6e83af64eb0515e0cf57fce15db https://git.kernel.org/stable/c/879947f4180bc6e83af64eb0515e0cf57fce15db