CVE-2026-72037

What the bug is

lan743x_hardware_init() calls pci11x1x_strap_get_status() during the PCI11x1x probe sequence. That helper acquires the Ethernet subsystem hardware lock via lan743x_hs_syslock_acquire(), which relies on adapter->eth_syslock_spinlock to serialize access. The spinlock is currently initialized only after the strap status is read. With CONFIG_DEBUG_SPINLOCK enabled, taking the zeroed initialized spinlock can trip the spinlock debug check. Fix by initializing adapter->eth_syslock_spinlock before reading the strap status so the probe path never attempts to lock an uninitialized spinlock.

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/net/ethernet/microchip/lan743x_main.c

What this is

MICROCHIP LAN743X ETHERNET DRIVERMAINTAINERS section matched on drivers/net/ethernet/microchip/lan743x_* · netdev@vger.kernel.org · Maintained

Kernel module

lan743x

Check it on the machine

grep -wE 'CONFIG_ETHERNET|CONFIG_LAN743X|CONFIG_NET_VENDOR_MICROCHIP' /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 lan743x

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.

• bookwormMnot built on amd64/cloud-amd64, arm64/cloud-arm64
• trixieMnot built on amd64/cloud-amd64, arm64/cloud-arm64, armel/rpi
• forky, sidMnot built on amd64/cloud-amd64, arm64/cloud-arm64

M

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

Build switches

CONFIG_ETHERNET, CONFIG_LAN743X, CONFIG_NET_VENDOR_MICROCHIP

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

2026-08-15 (2 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 11.0% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/net

Upstream fixes

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

Introduced	Fixed in	Commit
6.0	6.1.178	dfaefd9a7808
6.0	6.6.145	6523daa6852b
6.0	6.12.97	b6a93a42e0e6
6.0	6.18.40	99a6f37b113c
6.0	7.1.5	b99e890e6b32
6.0	7.2	39139b1c1c2b