Subject: CVE-2022-48646: sfc/siena: fix null pointer dereference in efx_hard_start_xmit

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

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

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

sfc/siena: fix null pointer dereference in efx_hard_start_xmit

Like in previous patch for sfc, prevent potential (but unlikely) NULL
pointer dereference.

The Linux kernel CVE team has assigned CVE-2022-48646 to this issue.

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

	Issue introduced in 5.10 with commit 12804793b17c and fixed in 5.19.12 with commit a4eadca702df
	Issue introduced in 5.10 with commit 12804793b17c and fixed in 6.0 with commit 589c6eded10c

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-2022-48646
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/net/ethernet/sfc/siena/tx.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/a4eadca702dff0768dd01be6789bbec2a18e5b0a
	https://git.kernel.org/stable/c/589c6eded10c77a12b7b2cf235b6b19a2bdb91fa