CVE-2026-74272

What the bug is

Sungwoo noticed that the sysfs trigger to delete a region may try to delete a region multiple times. It also has no exclusion relative to the kernel releasing the region via CXL root device teardown. Instead of installing new cxl root devres actions per region, use the existing root decoder unregistration event to remove all remaining regions. An xarray of regions replaces a devres list of regions. This handles 3 separate issues with the old approach: 1/ sysfs users racing to delete the same region: no longer possible now that the regions_lock is held over the lookup and deletion. 2/ multiple actions triggering deletion of the same region: solved by erasing regions while holding @regions_lock, and only proceeding on successful erasure. 3/ userspace racing devres_release_all() to trigger the devres not found warning: solved by sysfs unregistration not requiring a release action

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

drivers/cxl/core/core.h
drivers/cxl/core/port.c
drivers/cxl/core/region.c
drivers/cxl/cxl.h

What this is

COMPUTE EXPRESS LINK (CXL)MAINTAINERS section matched on drivers/cxl/ · linux-cxl@vger.kernel.org · Maintained

Check it on the machine

grep -w CONFIG_CXL_BUS /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

Show whether Debian builds this, per release

Debian builds this, but not on every flavour. At least one release below builds the code on some of its kernel flavours and not on others, so the answer depends on the architecture and flavour installed.

• bookwormYnot built on armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, i386/686, i386/686-pae, i386/rt/686-pae
• trixieYnot built on armel/rpi, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, s390x/s390x
• forky, sidYnot built on armhf/armmp, armhf/armmp-lpae, loong64/loong64, s390x/s390x

Y

built in where it is built at all; some flavours do not build it

Build switch

CONFIG_CXL_BUS

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-08-15 (2 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.20%, higher than 8.9% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/cxl

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
6.0	7.1.5	be44c1c04f85
6.0	7.2	4dd86ca99ffc