Subject: CVE-2020-36782: i2c: imx-lpi2c: fix reference leak when pm_runtime_get_sync fails

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

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

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

i2c: imx-lpi2c: fix reference leak when pm_runtime_get_sync fails

The PM reference count is not expected to be incremented on
return in lpi2c_imx_master_enable.

However, pm_runtime_get_sync will increment the PM reference
count even failed. Forgetting to putting operation will result
in a reference leak here.

Replace it with pm_runtime_resume_and_get to keep usage
counter balanced.

The Linux kernel CVE team has assigned CVE-2020-36782 to this issue.

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

	Issue introduced in 4.16 with commit 13d6eb20fc79 and fixed in 5.4.119 with commit 815859cb1d23
	Issue introduced in 4.16 with commit 13d6eb20fc79 and fixed in 5.10.37 with commit cc49d2064142
	Issue introduced in 4.16 with commit 13d6eb20fc79 and fixed in 5.11.21 with commit bb300acc867e
	Issue introduced in 4.16 with commit 13d6eb20fc79 and fixed in 5.12.4 with commit b100650d80cd
	Issue introduced in 4.16 with commit 13d6eb20fc79 and fixed in 5.13 with commit 278e5bbdb9a9

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-2020-36782
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/busses/i2c-imx-lpi2c.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/815859cb1d2302e74f11bf6894bceace9ca9eb4a
	https://git.kernel.org/stable/c/cc49d206414240483bb93ffa3d80243e6a776916
	https://git.kernel.org/stable/c/bb300acc867e937edc2a6898e92b21f88e4e4e66
	https://git.kernel.org/stable/c/b100650d80cd2292f6c152f5f2943b5944b3e8ce
	https://git.kernel.org/stable/c/278e5bbdb9a94fa063c0f9bcde2479d0b8042462