CVE-2026-89512: remoteproc: scp: Fix device reference leak on failed lookup

CVE-2026-89512: remoteproc: scp: Fix device reference leak on failed lookup

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

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

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

remoteproc: scp: Fix device reference leak on failed lookup

Make sure to drop the reference taken to the SCP device when attempting
to look up its driver data before the driver has been bound.

Note that holding a reference to a device does not prevent its driver
data from going away.

The Linux kernel CVE team has assigned CVE-2026-89512 to this issue.


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

	Issue introduced in 5.6 with commit 63c13d61eafe4606f1c16c54da40c4eee78e9edf and fixed in 6.12.109 with commit f794c930d8238e370fd61fcb12cc301ae098231b
	Issue introduced in 5.6 with commit 63c13d61eafe4606f1c16c54da40c4eee78e9edf and fixed in 6.18.50 with commit c7e32814a6bf20f792d05f0bc9f94f0606311bc6
	Issue introduced in 5.6 with commit 63c13d61eafe4606f1c16c54da40c4eee78e9edf and fixed in 7.2.4 with commit 440bcb0948a12c9104b6dcca99a2cfb0db49b22a
	Issue introduced in 5.6 with commit 63c13d61eafe4606f1c16c54da40c4eee78e9edf and fixed in 7.3-rc1 with commit 22f9efb3ae07f966a1901d929d16df1388cce65c

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-2026-89512
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/remoteproc/mtk_scp.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/f794c930d8238e370fd61fcb12cc301ae098231b
	https://git.kernel.org/stable/c/c7e32814a6bf20f792d05f0bc9f94f0606311bc6
	https://git.kernel.org/stable/c/440bcb0948a12c9104b6dcca99a2cfb0db49b22a
	https://git.kernel.org/stable/c/22f9efb3ae07f966a1901d929d16df1388cce65c