CVE-2022-49765 net/9p: use a dedicated spinlock for trans_fd

What is CVE-2022-49765?

CVE-2022-49765 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/9p: use a dedicated spinlock for trans_fd

Shamelessly copying the explanation from Tetsuo Handa's suggested patch[1] (slightly reworded): syzbot is reporting inconsistent lock state in p9_req_put()[2], for p9_tag_remove() from p9_req_put() from IRQ context is using spin_lock_irqsave() on "struct p9_client"->lock but trans_fd (not from IRQ context) is using spin_lock().

Since the locks actually protect different things in client.c and in trans_fd.c, just replace trans_fd.c's lock by a new one specific to the transport (client.c's protect the idr for fid/tag allocations, while trans_fd.c's protects its own req list and request status field that acts as the transport's state machine)

Weakness: CWE-667

Which versions are affected by CVE-2022-49765?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2022-49765?

Apply the vendor's patch.

Is CVE-2022-49765 being exploited?

There is no known exploitation of CVE-2022-49765 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 DEBIAN-CVE-2022-49765, GHSA-5rmr-vqfv-62q6, ROOT-OS-DEBIAN-11-CVE-2022-49765, UBUNTU-CVE-2022-49765.