CVE-2023-52508: nvme-fc: Prevent null pointer dereference in nvme_fc_io_getuuid()

CVE-2023-52508: nvme-fc: Prevent null pointer dereference in nvme_fc_io_getuuid()

[Greg Kroah-Hartman]

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

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

nvme-fc: Prevent null pointer dereference in nvme_fc_io_getuuid()

The nvme_fc_fcp_op structure describing an AEN operation is initialized with a
null request structure pointer. An FC LLDD may make a call to
nvme_fc_io_getuuid passing a pointer to an nvmefc_fcp_req for an AEN operation.

Add validation of the request structure pointer before dereference.

The Linux kernel CVE team has assigned CVE-2023-52508 to this issue.


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

	Fixed in 6.1.56 with commit be90c9e29dd5
	Fixed in 6.5.6 with commit dd46b3ac7322
	Fixed in 6.6 with commit 8ae5b3a685dc

Please see https://www.kernel.org or 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-2023-52508
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:
	drivers/nvme/host/fc.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/be90c9e29dd59b7d19a73297a1590ff3ec1d22ea
	https://git.kernel.org/stable/c/dd46b3ac7322baf3772b33b29726e94f98289db7
	https://git.kernel.org/stable/c/8ae5b3a685dc59a8cf7ccfe0e850999ba9727a3c