CVE-2022-49705: 9p: fix fid refcount leak in v9fs_vfs_atomic_open_dotl

CVE-2022-49705: 9p: fix fid refcount leak in v9fs_vfs_atomic_open_dotl

[Greg Kroah-Hartman]

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

9p: fix fid refcount leak in v9fs_vfs_atomic_open_dotl

We need to release directory fid if we fail halfway through open

This fixes fid leaking with xfstests generic 531

The Linux kernel CVE team has assigned CVE-2022-49705 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 5.11 with commit 6636b6dcc3db2258cd0585b8078c1c225c4b6dde and fixed in 5.15.51 with commit 22832ac3eb5be3f7168816a76b64c1284e12eb3c
	Issue introduced in 5.11 with commit 6636b6dcc3db2258cd0585b8078c1c225c4b6dde and fixed in 5.18.8 with commit 8bc5412ba1a45edfd1e451874c483c26a097af2b
	Issue introduced in 5.11 with commit 6636b6dcc3db2258cd0585b8078c1c225c4b6dde and fixed in 5.19 with commit beca774fc51a9ba8abbc869cf0c3d965ff17cd24

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2022-49705
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	fs/9p/vfs_inode_dotl.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/22832ac3eb5be3f7168816a76b64c1284e12eb3c
	https://git.kernel.org/stable/c/8bc5412ba1a45edfd1e451874c483c26a097af2b
	https://git.kernel.org/stable/c/beca774fc51a9ba8abbc869cf0c3d965ff17cd24