CVE-2022-49448: soc: bcm: Check for NULL return of devm_kzalloc()

CVE-2022-49448: soc: bcm: Check for NULL return of devm_kzalloc()

[Greg Kroah-Hartman]

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

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

soc: bcm: Check for NULL return of devm_kzalloc()

As the potential failure of allocation, devm_kzalloc() may return NULL.  Then
the 'pd->pmb' and the follow lines of code may bring null pointer dereference.

Therefore, it is better to check the return value of devm_kzalloc() to avoid
this confusion.

The Linux kernel CVE team has assigned CVE-2022-49448 to this issue.


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

	Issue introduced in 5.12 with commit 8bcac4011ebe0dbdd46fd55b036ee855c95702d3 and fixed in 5.15.46 with commit 5650e103bfc70156001615861fb8aafb3947da6e
	Issue introduced in 5.12 with commit 8bcac4011ebe0dbdd46fd55b036ee855c95702d3 and fixed in 5.17.14 with commit 36339ea7bae4943be01c8e9545e46e334591fecd
	Issue introduced in 5.12 with commit 8bcac4011ebe0dbdd46fd55b036ee855c95702d3 and fixed in 5.18.3 with commit b48b98743b568bb219152ba2e15af6ef0d3d8a9b
	Issue introduced in 5.12 with commit 8bcac4011ebe0dbdd46fd55b036ee855c95702d3 and fixed in 5.19 with commit b4bd2aafacce48db26b0a213d849818d940556dd

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-2022-49448
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/soc/bcm/bcm63xx/bcm-pmb.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/5650e103bfc70156001615861fb8aafb3947da6e
	https://git.kernel.org/stable/c/36339ea7bae4943be01c8e9545e46e334591fecd
	https://git.kernel.org/stable/c/b48b98743b568bb219152ba2e15af6ef0d3d8a9b
	https://git.kernel.org/stable/c/b4bd2aafacce48db26b0a213d849818d940556dd