CVE-2025-37787 net: dsa: mv88e6xxx: avoid unregistering devlink regions which were never registered

What is CVE-2025-37787?

CVE-2025-37787 is a medium-severity vulnerability in Linux kernel, published on 1 May 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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

net: dsa: mv88e6xxx: avoid unregistering devlink regions which were never registered

Russell King reports that a system with mv88e6xxx dereferences a NULL pointer when unbinding this driver: https://lore.kernel.org/netdev/[email protected]/

The crash seems to be in devlink_region_destroy(), which is not NULL tolerant but is given a NULL devlink global region pointer.

At least on some chips, some devlink regions are conditionally registered since the blamed commit, see mv88e6xxx_setup_devlink_regions_global():

if (cond && !cond(chip)) continue;

These are MV88E6XXX_REGION_STU and MV88E6XXX_REGION_PVT. If the chip does not have an STU or PVT, it should crash like this.

To fix the issue, avoid unregistering those regions which are NULL, i.e. were skipped at mv88e6xxx_setup_devlink_regions_global() time.

Weakness: CWE-476

Which versions are affected by CVE-2025-37787?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2025-37787?

Apply the vendor's patch.

Is CVE-2025-37787 being exploited?

There is no known exploitation of CVE-2025-37787 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2025-37787, DEBIAN-CVE-2025-37787, GHSA-hfj5-q228-92r2, ROOT-OS-DEBIAN-12-CVE-2025-37787, ROOT-OS-UBUNTU-2204-CVE-2025-37787, ROOT-OS-UBUNTU-2404-CVE-2025-37787 and 1 more.