---
id: CVE-2025-38323
title: 'net: atm: add lec_mutex'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  net: atm: add lec_mutex

  syzbot found its way in net/atm/lec.c, and found an error path
  in lecd_attach() could leave a dangling pointer in dev_lec[].

  Add a mutex to pr…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    e91274cc7ed88ab5bdc62d426067c82b0b118a0b
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    a7a713dfb5f9477345450f27c7c0741864511192
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    17e156a94e94a906a570dbf9b48877956c60bef8
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    18e8f0c4f826fb08c2d3825cdd6c57e24b207e0a
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    dffd03422ae6a459039c8602f410e6c0f4cbc6c8
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    f4d80b16ecc4229f7e6345158ef34c36be323f0e
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    64b378db28a967f7b271b055380c2360279aa424
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    d13a3824bfd2b4774b671a75cf766a16637a0e67
  - Linux 2.6.12
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T20:54:34.639924Z'
published: '2025-07-10'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T21:02:33.036Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-38323'
references:
  - url: 'https://git.kernel.org/stable/c/e91274cc7ed88ab5bdc62d426067c82b0b118a0b'
  - url: 'https://git.kernel.org/stable/c/a7a713dfb5f9477345450f27c7c0741864511192'
  - url: 'https://git.kernel.org/stable/c/17e156a94e94a906a570dbf9b48877956c60bef8'
  - url: 'https://git.kernel.org/stable/c/18e8f0c4f826fb08c2d3825cdd6c57e24b207e0a'
  - url: 'https://git.kernel.org/stable/c/dffd03422ae6a459039c8602f410e6c0f4cbc6c8'
  - url: 'https://git.kernel.org/stable/c/f4d80b16ecc4229f7e6345158ef34c36be323f0e'
  - url: 'https://git.kernel.org/stable/c/64b378db28a967f7b271b055380c2360279aa424'
  - url: 'https://git.kernel.org/stable/c/d13a3824bfd2b4774b671a75cf766a16637a0e67'
tags:
  - cve.org
epss: 0.00212
epssPercentile: 0.11532
ingestedAt: '2026-11-05T22:38:31.953Z'
---

## Overview

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

net: atm: add lec_mutex

syzbot found its way in net/atm/lec.c, and found an error path
in lecd_attach() could leave a dangling pointer in dev_lec[].

Add a mutex to protect dev_lecp[] uses from lecd_attach(),
lec_vcc_attach() and lec_mcast_attach().

Following patch will use this mutex for /proc/net/atm/lec.

BUG: KASAN: slab-use-after-free in lecd_attach net/atm/lec.c:751 [inline]
BUG: KASAN: slab-use-after-free in lane_ioctl+0x2224/0x23e0 net/atm/lec.c:1008
Read of size 8 at addr ffff88807c7b8e68 by task syz.1.17/6142

CPU: 1 UID: 0 PID: 6142 Comm: syz.1.17 Not tainted 6.16.0-rc1-syzkaller-00239-g08215f5486ec #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
  __dump_stack lib/dump_stack.c:94 [inline]
  dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
  print_address_description mm/kasan/report.c:408 [inline]
  print_report+0xcd/0x680 mm/kasan/report.c:521
  kasan_report+0xe0/0x110 mm/kasan/report.c:634
  lecd_attach net/atm/lec.c:751 [inline]
  lane_ioctl+0x2224/0x23e0 net/atm/lec.c:1008
  do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159
  sock_do_ioctl+0x118/0x280 net/socket.c:1190
  sock_ioctl+0x227/0x6b0 net/socket.c:1311
  vfs_ioctl fs/ioctl.c:51 [inline]
  __do_sys_ioctl fs/ioctl.c:907 [inline]
  __se_sys_ioctl fs/ioctl.c:893 [inline]
  __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
 </TASK>

Allocated by task 6132:
  kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
  kasan_save_track+0x14/0x30 mm/kasan/common.c:68
  poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
  __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
  kasan_kmalloc include/linux/kasan.h:260 [inline]
  __do_kmalloc_node mm/slub.c:4328 [inline]
  __kvmalloc_node_noprof+0x27b/0x620 mm/slub.c:5015
  alloc_netdev_mqs+0xd2/0x1570 net/core/dev.c:11711
  lecd_attach net/atm/lec.c:737 [inline]
  lane_ioctl+0x17db/0x23e0 net/atm/lec.c:1008
  do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159
  sock_do_ioctl+0x118/0x280 net/socket.c:1190
  sock_ioctl+0x227/0x6b0 net/socket.c:1311
  vfs_ioctl fs/ioctl.c:51 [inline]
  __do_sys_ioctl fs/ioctl.c:907 [inline]
  __se_sys_ioctl fs/ioctl.c:893 [inline]
  __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6132:
  kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
  kasan_save_track+0x14/0x30 mm/kasan/common.c:68
  kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
  poison_slab_object mm/kasan/common.c:247 [inline]
  __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
  kasan_slab_free include/linux/kasan.h:233 [inline]
  slab_free_hook mm/slub.c:2381 [inline]
  slab_free mm/slub.c:4643 [inline]
  kfree+0x2b4/0x4d0 mm/slub.c:4842
  free_netdev+0x6c5/0x910 net/core/dev.c:11892
  lecd_attach net/atm/lec.c:744 [inline]
  lane_ioctl+0x1ce8/0x23e0 net/atm/lec.c:1008
  do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159
  sock_do_ioctl+0x118/0x280 net/socket.c:1190
  sock_ioctl+0x227/0x6b0 net/socket.c:1311
  vfs_ioctl fs/ioctl.c:51 [inline]
  __do_sys_ioctl fs/ioctl.c:907 [inline]
  __se_sys_ioctl fs/ioctl.c:893 [inline]
  __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893

## Affected

- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < e91274cc7ed88ab5bdc62d426067c82b0b118a0b`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < a7a713dfb5f9477345450f27c7c0741864511192`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 17e156a94e94a906a570dbf9b48877956c60bef8`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 18e8f0c4f826fb08c2d3825cdd6c57e24b207e0a`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < dffd03422ae6a459039c8602f410e6c0f4cbc6c8`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f4d80b16ecc4229f7e6345158ef34c36be323f0e`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 64b378db28a967f7b271b055380c2360279aa424`
- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < d13a3824bfd2b4774b671a75cf766a16637a0e67`
- `Linux 2.6.12`

## Remediation

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