CVE-2026-64168: spi: sprd: fix error pointer deref after DMA setup failure

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

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

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

spi: sprd: fix error pointer deref after DMA setup failure

The driver falls back to PIO mode if DMA setup fails during probe.

Make sure to check the dma.enabled flag before trying to release the DMA
channels also on late probe errors to avoid dereferencing an error
pointer (or attempting to release a channel a second time).

This issue was flagged by Sashiko when reviewing a devres allocation
conversion patch.

The Linux kernel CVE team has assigned CVE-2026-64168 to this issue.


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

	Issue introduced in 5.1 with commit 386119bc7be9fa5114ced0274a22a943df890b4b and fixed in 5.10.258 with commit be74e276111f3c23b8e040c8c5e308f67a573add
	Issue introduced in 5.1 with commit 386119bc7be9fa5114ced0274a22a943df890b4b and fixed in 5.15.209 with commit a8f233fb0c7be29b97cd249f64120bf35ce72805
	Issue introduced in 5.1 with commit 386119bc7be9fa5114ced0274a22a943df890b4b and fixed in 6.1.175 with commit 0cdea166c1a07c200caf9d0b722224fca43b23ae
	Issue introduced in 5.1 with commit 386119bc7be9fa5114ced0274a22a943df890b4b and fixed in 6.6.142 with commit 450c319dd04d0eeff4184889768f7ada826a2e35
	Issue introduced in 5.1 with commit 386119bc7be9fa5114ced0274a22a943df890b4b and fixed in 6.12.92 with commit b6f1acf4e57ccf708cdc0cb70f5bb5b65162963b
	Issue introduced in 5.1 with commit 386119bc7be9fa5114ced0274a22a943df890b4b and fixed in 6.18.34 with commit be409d2bbe9ca7da7b05cc7dde7499bc481f0766
	Issue introduced in 5.1 with commit 386119bc7be9fa5114ced0274a22a943df890b4b and fixed in 7.0.11 with commit c33b4496e95d04722055446c0a31213639438536
	Issue introduced in 5.1 with commit 386119bc7be9fa5114ced0274a22a943df890b4b and fixed in 7.1 with commit 3d67fffb74267772d461c02c67f1eff893ad547d

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-2026-64168
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/spi/spi-sprd.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/be74e276111f3c23b8e040c8c5e308f67a573add
	https://git.kernel.org/stable/c/a8f233fb0c7be29b97cd249f64120bf35ce72805
	https://git.kernel.org/stable/c/0cdea166c1a07c200caf9d0b722224fca43b23ae
	https://git.kernel.org/stable/c/450c319dd04d0eeff4184889768f7ada826a2e35
	https://git.kernel.org/stable/c/b6f1acf4e57ccf708cdc0cb70f5bb5b65162963b
	https://git.kernel.org/stable/c/be409d2bbe9ca7da7b05cc7dde7499bc481f0766
	https://git.kernel.org/stable/c/c33b4496e95d04722055446c0a31213639438536
	https://git.kernel.org/stable/c/3d67fffb74267772d461c02c67f1eff893ad547d