Subject: CVE-2022-48832: audit: don't deref the syscall args when checking the openat2 open_how::flags

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

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

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

audit: don't deref the syscall args when checking the openat2 open_how::flags

As reported by Jeff, dereferencing the openat2 syscall argument in
audit_match_perm() to obtain the open_how::flags can result in an
oops/page-fault.  This patch fixes this by using the open_how struct
that we store in the audit_context with audit_openat2_how().

Independent of this patch, Richard Guy Briggs posted a similar patch
to the audit mailing list roughly 40 minutes after this patch was
posted.

The Linux kernel CVE team has assigned CVE-2022-48832 to this issue.

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

	Issue introduced in 5.16 with commit 1c30e3af8a79 and fixed in 5.16.10 with commit 310c9ddfdf1f
	Issue introduced in 5.16 with commit 1c30e3af8a79 and fixed in 5.17 with commit 7a82f89de92a

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-2022-48832
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:
	kernel/auditsc.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/310c9ddfdf1f8d3c9834f02175eae79c8b254b6c
	https://git.kernel.org/stable/c/7a82f89de92aac5a244d3735b2bd162c1147620c