Subject: CVE-2021-47425: i2c: acpi: fix resource leak in reconfiguration device addition

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

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

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

i2c: acpi: fix resource leak in reconfiguration device addition

acpi_i2c_find_adapter_by_handle() calls bus_find_device() which takes a
reference on the adapter which is never released which will result in a
reference count leak and render the adapter unremovable.  Make sure to
put the adapter after creating the client in the same manner that we do
for OF.

[wsa: fixed title]

The Linux kernel CVE team has assigned CVE-2021-47425 to this issue.

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

	Issue introduced in 4.8 with commit 525e6fabeae2 and fixed in 4.14.251 with commit b8090a84d775
	Issue introduced in 4.8 with commit 525e6fabeae2 and fixed in 4.19.211 with commit 3d9d458a8aaa
	Issue introduced in 4.8 with commit 525e6fabeae2 and fixed in 5.4.153 with commit 60bacf259e8c
	Issue introduced in 4.8 with commit 525e6fabeae2 and fixed in 5.10.73 with commit f86de018fd7a
	Issue introduced in 4.8 with commit 525e6fabeae2 and fixed in 5.14.12 with commit 90f1077c9184
	Issue introduced in 4.8 with commit 525e6fabeae2 and fixed in 5.15 with commit 6558b646ce1c

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-2021-47425
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/i2c/i2c-core-acpi.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/b8090a84d7758b929d348bafbd86bb7a10c5fb63
	https://git.kernel.org/stable/c/3d9d458a8aaafa47268ea4f1b4114a9f12927989
	https://git.kernel.org/stable/c/60bacf259e8c2eb2324f3e13275200baaee9494b
	https://git.kernel.org/stable/c/f86de018fd7a24ee07372d55ffa7824f0c674a95
	https://git.kernel.org/stable/c/90f1077c9184ec2ae9989e4642f211263f301694
	https://git.kernel.org/stable/c/6558b646ce1c2a872fe1c2c7cb116f05a2c1950f