Subject: CVE-2021-47522: HID: bigbenff: prevent null pointer dereference

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

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

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

HID: bigbenff: prevent null pointer dereference

When emulating the device through uhid, there is a chance we don't have
output reports and so report_field is null.

The Linux kernel CVE team has assigned CVE-2021-47522 to this issue.

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

	Fixed in 5.4.165 with commit 8e0ceff632f4
	Fixed in 5.10.85 with commit 6272b17001e6
	Fixed in 5.15.8 with commit 58f15f5ae778
	Fixed in 5.16 with commit 918aa1ef104d

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-2021-47522
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/hid/hid-bigbenff.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/8e0ceff632f48175ec7fb4706129c55ca8a7c7bd
	https://git.kernel.org/stable/c/6272b17001e6fdcf7b4a16206287010a1523fa6e
	https://git.kernel.org/stable/c/58f15f5ae7786c824868f3a7e093859b74669ce7
	https://git.kernel.org/stable/c/918aa1ef104d286d16b9e7ef139a463ac7a296f0