CVE-2023-52638 can: j1939: prevent deadlock by changing j1939_socks_lock to rwlock

What is CVE-2023-52638?

CVE-2023-52638 is a medium-severity vulnerability in Linux kernel, published on 3 Apr 2024. 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:

can: j1939: prevent deadlock by changing j1939_socks_lock to rwlock

The following 3 locks would race against each other, causing the deadlock situation in the Syzbot bug report:

- j1939_socks_lock - active_session_list_lock - sk_session_queue_lock

A reasonable fix is to change j1939_socks_lock to an rwlock, since in the rare situations where a write lock is required for the linked list that j1939_socks_lock is protecting, the code does not attempt to acquire any more locks. This would break the circular lock dependency, where, for example, the current thread already locks j1939_socks_lock and attempts to acquire sk_session_queue_lock, and at the same time, another thread attempts to acquire j1939_socks_lock while holding sk_session_queue_lock.

NOTE: This patch along does not fix the unregister_netdevice bug reported by Syzbot; instead, it solves a deadlock situation to prepare for one or more further patches to actually fix the Syzbot bug, which appears to be a reference counting problem within the j1939 codebase.

[mkl: remove unrelated newline change]

Weakness: CWE-667

Which versions are affected by CVE-2023-52638?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-52638?

Apply the vendor's patch.

Is CVE-2023-52638 being exploited?

There is no known exploitation of CVE-2023-52638 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-2023-52638, DEBIAN-CVE-2023-52638, GHSA-2595-73wg-wgrp, ROOT-OS-DEBIAN-11-CVE-2023-52638, UBUNTU-CVE-2023-52638.