Subject: CVE-2022-48831: ima: fix reference leak in asymmetric_verify()

From: Greg Kroah-Hartman <[email-masked]>

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

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

ima: fix reference leak in asymmetric_verify()

Don't leak a reference to the key if its algorithm is unknown.

The Linux kernel CVE team has assigned CVE-2022-48831 to this issue.

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

	Issue introduced in 5.13 with commit 947d70597236 and fixed in 5.15.24 with commit 0838d6d68182
	Issue introduced in 5.13 with commit 947d70597236 and fixed in 5.16.10 with commit 89f586d3398f
	Issue introduced in 5.13 with commit 947d70597236 and fixed in 5.17 with commit 926fd9f23b27

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-2022-48831
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:
	security/integrity/digsig_asymmetric.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/0838d6d68182f0b28a5434bc6d50727c4757e35b
	https://git.kernel.org/stable/c/89f586d3398f4cc0432ed870949dffb702940754
	https://git.kernel.org/stable/c/926fd9f23b27ca6587492c3f58f4c7f4cd01dad5