CVE-2026-90126

What the bug is

pcf8563_clkout_register_clk() registers the CLKOUT clock provider with of_clk_add_provider(), but nothing ever unwinds it: there is no of_clk_del_provider() call and the driver has no remove callback. Each of_clk_add_provider() allocates a struct of_clk_provider, takes a reference on the OF node and adds an entry to the global of_clk_providers list, none of which is released when the device is unbound. Every bind/unbind (or module reload) therefore leaks a provider structure and an of_node reference. The clock itself is already device-managed (devm_clk_register()); only the provider registration was not. Use devm_of_clk_add_hw_provider() so the provider is removed automatically on unbind. Tie it to the parent i2c device, whose OF node carries the #clock-cells and clock-output-names properties (the RTC class device has no OF node of its own).

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/rtc/rtc-pcf8563.c

What this is

REAL TIME CLOCK (RTC) SUBSYSTEMMAINTAINERS section matched on drivers/rtc/ · linux-rtc@vger.kernel.org · Maintained

Kernel module

rtc_pcf8563

Check it on the machine

grep -wE 'CONFIG_RTC_DRV_PCF8563|CONFIG_RTC_LIB' /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.

lsmod | grep -w rtc_pcf8563

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

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 amd64/amd64, amd64/cloud-amd64, amd64/rt/amd64, arm64/cloud-arm64, i386/686, i386/686-pae, i386/rt/686-pae, ppc64el/powerpc64le
• trixieBnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt/amd64, arm64/cloud-arm64, armel/rpi, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, s390x/s390x
• forky, sidBnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt-amd64, arm64/cloud-arm64, loong64/loong64, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, s390x/s390x
• bookworm · linux-6.12Ynot built on amd64/amd64, amd64/cloud-amd64, amd64/rt/amd64, arm64/cloud-arm64, ppc64el/powerpc64le, ppc64el/powerpc64le-64k

Y

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

B

built in on some, a module on others, absent on the rest

Build switches

CONFIG_RTC_DRV_PCF8563, CONFIG_RTC_LIB

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

2026-09-17 (31 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 10.6% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/rtc

Upstream fixes

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

Introduced	Fixed in	Commit
4.4	5.10.270	2b5622cf4ee2
4.4	5.15.221	36cb00c33bd8
4.4	6.1.188	30b7c63af50f
4.4	6.6.157	7afb8db47c4f
4.4	6.12.110	97edf3fd9a46
4.4	6.18.52	08a59c28c2bd
4.4	7.2.6	6218c0533a72
4.4	7.3	9c48a5368504

Debian advisories