Subject: CVE-2022-48933: netfilter: nf_tables: fix memory leak during stateful obj update

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

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

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

netfilter: nf_tables: fix memory leak during stateful obj update

stateful objects can be updated from the control plane.
The transaction logic allocates a temporary object for this purpose.

The ->init function was called for this object, so plain kfree() leaks
resources. We must call ->destroy function of the object.

nft_obj_destroy does this, but it also decrements the module refcount,
but the update path doesn't increment it.

To avoid special-casing the update object release, do module_get for
the update case too and release it via nft_obj_destroy().

The Linux kernel CVE team has assigned CVE-2022-48933 to this issue.

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

	Issue introduced in 5.4 with commit d62d0ba97b58 and fixed in 5.4.182 with commit 53026346a94c
	Issue introduced in 5.4 with commit d62d0ba97b58 and fixed in 5.10.103 with commit 7e9880e81d3f
	Issue introduced in 5.4 with commit d62d0ba97b58 and fixed in 5.15.26 with commit e96e204ee6fa
	Issue introduced in 5.4 with commit d62d0ba97b58 and fixed in 5.16.12 with commit 34bb90e407e3
	Issue introduced in 5.4 with commit d62d0ba97b58 and fixed in 5.17 with commit dad3bdeef45f

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-2022-48933
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:
	net/netfilter/nf_tables_api.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/53026346a94c43f35c32b18804041bc483271d87
	https://git.kernel.org/stable/c/7e9880e81d3fd6a43c202f205717485290432826
	https://git.kernel.org/stable/c/e96e204ee6fa46702f6c94c3c69a09e69e0eac52
	https://git.kernel.org/stable/c/34bb90e407e3288f610558beaae54ecaa32b11c4
	https://git.kernel.org/stable/c/dad3bdeef45f81a6e90204bcc85360bb76eccec7