---
id: CVE-2026-53035
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  bpf, sockmap: Fix af_unix iter deadlock

  bpf_iter_unix_seq_show() may deadlock when lock_sock_fast() takes the fast
  path and the iter prog attempts to update a sockmap.…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  bpf, sockmap: Fix af_unix iter deadlock

  bpf_iter_unix_seq_show() may deadlock when lock_sock_fast() takes the fast
  path and the iter prog attempts to update a sockmap.…
severity: none
published: '2026-06-24'
updated: '2026-07-10'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-53035'
references:
  - url: 'https://git.kernel.org/stable/c/3cef33b9813b78f227942572fb317afcd5c9ac94'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/4d328dd695383224aa750ddee6b4ad40c0f8d205'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/527057ebe8076dfbcaef51195ff1b7508646be2c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/66d9fab4565eafe1afe7ba0581f79b76073b60fa'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/87828b380956d4986f59f2c086e0b09b3e6cdaae'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/bd3592129f24243713673a07225cf1f15a9bb835'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00125
epssPercentile: 0.0191
ingestedAt: '2026-07-11T19:15:12.232Z'
---

## Overview

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

bpf, sockmap: Fix af_unix iter deadlock

bpf_iter_unix_seq_show() may deadlock when lock_sock_fast() takes the fast
path and the iter prog attempts to update a sockmap. Which ends up spinning
at sock_map_update_elem()'s bh_lock_sock():

WARNING: possible recursive locking detected
test_progs/1393 is trying to acquire lock:
ffff88811ec25f58 (slock-AF_UNIX){+...}-{3:3}, at: sock_map_update_elem+0xdb/0x1f0

but task is already holding lock:
ffff88811ec25f58 (slock-AF_UNIX){+...}-{3:3}, at: __lock_sock_fast+0x37/0xe0

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(slock-AF_UNIX);
  lock(slock-AF_UNIX);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

4 locks held by test_progs/1393:
 #0: ffff88814b59c790 (&p->lock){+.+.}-{4:4}, at: bpf_seq_read+0x59/0x10d0
 #1: ffff88811ec25fd8 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: bpf_seq_read+0x42c/0x10d0
 #2: ffff88811ec25f58 (slock-AF_UNIX){+...}-{3:3}, at: __lock_sock_fast+0x37/0xe0
 #3: ffffffff85a6a7c0 (rcu_read_lock){....}-{1:3}, at: bpf_iter_run_prog+0x51d/0xb00

Call Trace:
 dump_stack_lvl+0x5d/0x80
 print_deadlock_bug.cold+0xc0/0xce
 __lock_acquire+0x130f/0x2590
 lock_acquire+0x14e/0x2b0
 _raw_spin_lock+0x30/0x40
 sock_map_update_elem+0xdb/0x1f0
 bpf_prog_2d0075e5d9b721cd_dump_unix+0x55/0x4f4
 bpf_iter_run_prog+0x5b9/0xb00
 bpf_iter_unix_seq_show+0x1f7/0x2e0
 bpf_seq_read+0x42c/0x10d0
 vfs_read+0x171/0xb20
 ksys_read+0xff/0x200
 do_syscall_64+0x6b/0x3a0
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
