CVE-2026-80563

What the bug is

The "trigger" debugfs file has a hand-rolled ->write handler (trigger_write()) that dereferences the per-device gpio_la_poll_priv. The file is created with debugfs_create_file_unsafe(), and the handler never takes a debugfs reference. Nothing keeps the object alive while the handler runs. priv is allocated with devm_kzalloc(). devres frees it when the platform device is unbound. debugfs_create_file_unsafe() installs no full_proxy wrapper, so debugfs_remove_recursive() in gpio_la_poll_remove() does not wait for an in-flight trigger_write(). The blob_lock taken there does not help, because trigger_write() never takes it. A write that races an unbind therefore writes into freed memory: trigger_write() gpio_la_poll_remove() priv = m->private buf = memdup_user() [may sleep] mutex_lock(&priv->blob_lock) debugfs_remove_recursive() [no wait] mutex_unlock(&priv->blob_lock) (remove returns; devres frees priv) priv->trig_data = buf <-- use-after-free write priv->trig_len = count The race is reachable by root via /sys/bus/platform/drivers/gpio-sloppy-logic-analyzer/unbind. Create "trigger" with debugfs_create_file() instead. Its full_proxy wrapper makes debugfs_remove_recursive() drain any in-flight ->write before it returns. The use-after-free is confirmed under KASAN with a minimal reproducer of the same debugfs_create_file_unsafe() plus devm_kzalloc() pattern (available on request); it produces a slab-use-after-free write in the handler.

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/gpio/gpio-sloppy-logic-analyzer.c

What this is

GPIO SLOPPY LOGIC ANALYZERMAINTAINERS section matched on drivers/gpio/gpio-sloppy-logic-analyzer.c · Supported

Check it on the machine

grep -wE 'CONFIG_GPIOLIB|CONFIG_GPIO_SLOPPY_LOGIC_ANALYZER' /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 does not build this code in 4 releases. The build rule could not be established for 1 release, so nothing is claimed about those.

• bookworm?
• trixie, forky, sid, bookworm · linux-6.12n

?

not established - no Makefile entry for the affected file

n

not enabled on any flavour - this release does not build the code

Where a release above reads "not established", no build rule for the affected file was found in that release's kernel tree. That is a gap in this lookup, not a finding that the code is absent.

Build switches

CONFIG_GPIOLIB, CONFIG_GPIO_SLOPPY_LOGIC_ANALYZER

Reads as

all on means the file is compiled; any one off means it is not.

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

2026-08-26 (2 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 10.3% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

unimportantsource

Subsystem

drivers/gpio

Upstream fixes

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

Introduced	Fixed in	Commit
6.11	6.12.105	49a1ebb1ef2c
6.11	6.18.46	23e9f32c0c7d
6.11	7.1.10	24bef4918f6a
6.11	7.2	44f3468a0aef

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