CVE-2026-23167

Updated on 14 Feb 2026

Severity

4.7 Medium severity

Details

CVSS score
4.7
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Overview

About vulnerability

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

nfc: nci: Fix race between rfkill and nci_unregister_device().

syzbot reported the splat below 0 without a repro.

It indicates that struct nci_dev.cmd_wq had been destroyed before nci_close_device() was called via rfkill.

nci_dev.cmd_wq is only destroyed in nci_unregister_device(), which (I think) was called from virtual_ncidev_close() when syzbot close()d an fd of virtual_ncidev.

The problem is that nci_unregister_device() destroys nci_dev.cmd_wq first and then calls nfc_unregister_device(), which removes the device from rfkill by rfkill_unregister().

So, the device is still visible via rfkill even after nci_dev.cmd_wq is destroyed.

Let’s unregister the device from rfkill first in nci_unregister_device().

Note that we cannot call nfc_unregister_device() before nci_close_device() because

  1. nfc_unregister_device() calls device_del() which frees all memory allocated by devm_kzalloc() and linked to ndev->conn_info_list

  2. nci_rx_work() could try to queue nci_conn_info to ndev->conn_info_list which could be leaked

Thus, nfc_unregister_device() is split into two functions so we can remove rfkill interfaces only before nci_close_device().

WARNING: kernel/locking/lockdep.c:238 at hlock_class kernel/locking/lockdep.c:238 [inline], CPU#0: syz.0.8675/6349 WARNING: kernel/locking/lockdep.c:238 at check_wait_context kernel/locking/lockdep.c:4854 [inline], CPU#0: syz.0.8675/6349 WARNING: kernel/locking/lockdep.c:238 at __lock_acquire+0x39d/0x2cf0 kernel/locking/lockdep.c:5187, CPU#0: syz.0.8675/6349 Modules linked in: CPU: 0 UID: 0 PID: 6349 Comm: syz.0.8675 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 RIP: 0010:hlock_class kernel/locking/lockdep.c:238 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4854 [inline] RIP: 0010:__lock_acquire+0x3a4/0x2cf0 kernel/locking/lockdep.c:5187 Code: 18 00 4c 8b 74 24 08 75 27 90 e8 17 f2 fc 02 85 c0 74 1c 83 3d 50 e0 4e 0e 00 75 13 48 8d 3d 43 f7 51 0e 48 c7 c6 8b 3a de 8d <67> 48 0f b9 3a 90 31 c0 0f b6 98 c4 00 00 00 41 8b 45 20 25 ff 1f RSP: 0018:ffffc9000c767680 EFLAGS: 00010046 RAX: 0000000000000001 RBX: 0000000000040000 RCX: 0000000000080000 RDX: ffffc90013080000 RSI: ffffffff8dde3a8b RDI: ffffffff8ff24ca0 RBP: 0000000000000003 R08: ffffffff8fef35a3 R09: 1ffffffff1fde6b4 R10: dffffc0000000000 R11: fffffbfff1fde6b5 R12: 00000000000012a2 R13: ffff888030338ba8 R14: ffff888030338000 R15: ffff888030338b30 FS: 00007fa5995f66c0(0000) GS:ffff8881256f8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7e72f842d0 CR3: 00000000485a0000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868 touch_wq_lockdep_map+0xcb/0x180 kernel/workqueue.c:3940 __flush_workqueue+0x14b/0x14f0 kernel/workqueue.c:3982 nci_close_device+0x302/0x630 net/nfc/nci/core.c:567 nci_dev_down+0x3b/0x50 net/nfc/nci/core.c:639 nfc_dev_down+0x152/0x290 net/nfc/core.c:161 nfc_rfkill_set_block+0x2d/0x100 net/nfc/core.c:179 rfkill_set_block+0x1d2/0x440 net/rfkill/core.c:346 rfkill_fop_write+0x461/0x5a0 net/rfkill/core.c:1301 vfs_write+0x29a/0xb90 fs/read_write.c:684 ksys_write+0x150/0x270 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa59b39acb9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa5995f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa59b615fa0 RCX: 00007fa59b39acb9 RDX: 0000000000000008 RSI: 0000200000000080 RDI: 0000000000000007 RBP: 00007fa59b408bf7 R08: —truncated—

Details

Fixes

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
Debian 13 Planned
Proxmox VE 7 5.15 Released
47 kernels
  • 5.15.5-1-pve-5.15.5-1
  • 5.15.12-1-pve-5.15.12-2
  • 5.15.12-1-pve-5.15.12-3
  • 5.15.17-1-pve-5.15.17-1
  • 5.15.19-1-pve-5.15.19-1
  • 5.15.19-2-pve-5.15.19-2
  • 5.15.19-2-pve-5.15.19-3
  • 5.15.27-1-pve-5.15.27-1
  • 5.15.30-1-pve-5.15.30-1
  • 5.15.30-2-pve-5.15.30-3
  • 5.15.35-1-pve-5.15.35-1
  • 5.15.35-1-pve-5.15.35-2
  • 5.15.35-1-pve-5.15.35-3
  • 5.15.35-2-pve-5.15.35-4
  • 5.15.35-2-pve-5.15.35-5
  • 5.15.35-3-pve-5.15.35-6
  • 5.15.39-1-pve-5.15.39-1
  • 5.15.39-2-pve-5.15.39-2
  • 5.15.39-3-pve-5.15.39-3
  • 5.15.39-4-pve-5.15.39-4
  • 5.15.7-1-pve-5.15.7-1
  • 5.15.53-1-pve-5.15.53-1
  • 5.15.60-1-pve-5.15.60-1
  • 5.15.60-2-pve-5.15.60-2
  • 5.15.64-1-pve-5.15.64-1
  • 5.15.74-1-pve-5.15.74-1
  • 5.15.83-1-pve-5.15.83-1
  • 5.15.102-1-pve-5.15.102-1
  • 5.15.104-1-pve-5.15.104-1
  • 5.15.104-1-pve-5.15.104-2
  • 5.15.107-1-pve-5.15.107-1
  • 5.15.107-2-pve-5.15.107-2
  • 5.15.85-1-pve-5.15.85-1
  • 5.15.108-1-pve-5.15.108-1
  • 5.15.108-1-pve-5.15.108-2
  • 5.15.116-1-pve-5.15.116-1
  • 5.15.126-1-pve-5.15.126-1
  • 5.15.131-1-pve-5.15.131-1
  • 5.15.131-1-pve-5.15.131-2
  • 5.15.131-2-pve-5.15.131-3
  • 5.15.136-1-pve-5.15.136-1
  • 5.15.111-1-pve-5.15.111-1
  • 5.15.143-1-pve-5.15.143-1
  • 5.15.149-1-pve-5.15.149-1
  • 5.15.152-1-pve-5.15.152-1
  • 5.15.158-1-pve_5.15.158-1
  • 5.15.158-2-pve_5.15.158-2
Ubuntu 20.04 HWE AWS Released
57 kernels
  • 5.15.0-1026.30~20.04.2
  • 5.15.0-1022.26~20.04.1
  • 5.15.0-1023.27~20.04.1
  • 5.15.0-1021.25~20.04.1
  • 5.15.0-1020.24~20.04.1
  • 5.15.0-1017.21~20.04.1
  • 5.15.0-1019.23~20.04.1
  • 5.15.0-1014.18~20.04.1
  • 5.15.0-1015.19~20.04.1
  • 5.15.0-1018.22~20.04.1
  • 5.15.0-1027.31~20.04.1
  • 5.15.0-1028.32~20.04.1
  • 5.15.0-1030.34~20.04.1
  • 5.15.0-1031.35~20.04.1
  • 5.15.0-1033.37~20.04.1
  • 5.15.0-1034.38~20.04.1
  • 5.15.0-1035.39~20.04.1
  • 5.15.0-1036.40~20.04.1
  • 5.15.0-1037.41~20.04.1
  • 5.15.0-1038.43~20.04.1
  • 5.15.0-1039.44~20.04.1
  • 5.15.0-1040.45~20.04.1
  • 5.15.0-1041.46~20.04.1
  • 5.15.0-1043.48~20.04.1
  • 5.15.0-1044.49~20.04.1
  • 5.15.0-1045.50~20.04.1
  • 5.15.0-1047.52~20.04.1
  • 5.15.0-1048.53~20.04.1
  • 5.15.0-1049.54~20.04.1
  • 5.15.0-1050.55~20.04.1
  • 5.15.0-1051.56~20.04.1
  • 5.15.0-1052.57~20.04.1
  • 5.15.0-1053.58~20.04.1
  • 5.15.0-1055.60~20.04.1
  • 5.15.0-1056.61~20.04.1
  • 5.15.0-1057.63~20.04.1
  • 5.15.0-1058.64~20.04.1
  • 5.15.0-1061.67~20.04.1
  • 5.15.0-1062.68~20.04.1
  • 5.15.0-1063.69~20.04.1
  • 5.15.0-1064.70~20.04.1
  • 5.15.0-1065.71~20.04.1
  • 5.15.0-1066.72~20.04.1
  • 5.15.0-1067.73~20.04.1
  • 5.15.0-1068.74~20.04.1
  • 5.15.0-1069.75~20.04.1
  • 5.15.0-1070.76~20.04.1
  • 5.15.0-1071.77~20.04.1
  • 5.15.0-1072.78~20.04.1
  • 5.15.0-1073.79~20.04.1
  • 5.15.0-1075.82~20.04.1
  • 5.15.0-1077.84~20.04.1
  • 5.15.0-1080.87~20.04.1
  • 5.15.0-1081.88~20.04.1
  • 5.15.0-1082.89~20.04.1
  • 5.15.0-1083.90~20.04.1
  • 5.15.0-1084.91~20.04.1
Ubuntu 20.04 HWE Azure Released
40 kernels
  • 5.15.0-1029.36~20.04.1
  • 5.15.0-1022.27~20.04.1
  • 5.15.0-1023.29~20.04.1
  • 5.15.0-1021.26~20.04.1
  • 5.15.0-1020.25~20.04.1
  • 5.15.0-1017.20~20.04.1
  • 5.15.0-1019.24~20.04.1
  • 5.15.0-1008.9~20.04.1
  • 5.15.0-1013.16~20.04.1
  • 5.15.0-1014.17~20.04.1
  • 5.15.0-1024.30~20.04.1
  • 5.15.0-1034.41~20.04.1
  • 5.15.0-1049.56~20.04.1
  • 5.15.0-1050.57~20.04.1
  • 5.15.0-1054.62~20.04.1
  • 5.15.0-1056.64~20.04.1
  • 5.15.0-1057.65~20.04.1
  • 5.15.0-1058.66~20.04.2
  • 5.15.0-1059.67~20.04.1
  • 5.15.0-1060.69~20.04.1
  • 5.15.0-1061.70~20.04.1
  • 5.15.0-1063.72~20.04.1
  • 5.15.0-1064.73~20.04.1
  • 5.15.0-1067.76~20.04.1
  • 5.15.0-1068.77~20.04.1
  • 5.15.0-1065.74~20.04.1
  • 5.15.0-1070.79~20.04.1
  • 5.15.0-1071.80~20.04.1
  • 5.15.0-1072.81~20.04.1
  • 5.15.0-1073.82~20.04.1
  • 5.15.0-1074.83~20.04.1
  • 5.15.0-1075.84~20.04.1
  • 5.15.0-1078.87~20.04.1
  • 5.15.0-1079.88~20.04.1
  • 5.15.0-1081.90~20.04.1
  • 5.15.0-1082.91~20.04.1
  • 5.15.0-1086.95~20.04.1
  • 5.15.0-1087.96~20.04.1
  • 5.15.0-1088.97~20.04.1
  • 5.15.0-1089.98~20.04.1
Ubuntu 22.04 Released
92 kernels
  • 5.15.0-27.28
  • 5.15.0-33.34
  • 5.15.0-37.39
  • 5.15.0-39.42
  • 5.15.0-25.25
  • 5.15.0-28.29
  • 5.15.0-29.30
  • 5.15.0-30.31
  • 5.15.0-41.44
  • 5.15.0-43.46
  • 5.15.0-46.49
  • 5.15.0-35.36
  • 5.15.0-47.51
  • 5.15.0-48.54
  • 5.15.0-40.43
  • 5.15.0-50.56
  • 5.15.0-52.58
  • 5.15.0-53.59
  • 5.15.0-56.62
  • 5.15.0-54.60
  • 5.15.0-57.63
  • 5.15.0-58.64
  • 5.15.0-60.66
  • 5.15.0-67.74
  • 5.15.0-69.76
  • 5.15.0-70.77
  • 5.15.0-71.78
  • 5.15.0-72.79
  • 5.15.0-68.75
  • 5.15.0-73.80
  • 5.15.0-75.82
  • 5.15.0-76.83
  • 5.15.0-78.85
  • 5.15.0-79.86
  • 5.15.0-82.91
  • 5.15.0-83.92
  • 5.15.0-84.93
  • 5.15.0-86.96
  • 5.15.0-74.81
  • 5.15.0-87.97
  • 5.15.0-88.98
  • 5.15.0-89.99
  • 5.15.0-91.101
  • 5.15.0-92.102
  • 5.15.0-94.104
  • 5.15.0-97.107
  • 5.15.0-100.110
  • 5.15.0-101.111
  • 5.15.0-102.112
  • 5.15.0-105.115
  • 5.15.0-106.116
  • 5.15.0-107.117
  • 5.15.0-112.122
  • 5.15.0-113.123
  • 5.15.0-116.126
  • 5.15.0-117.127
  • 5.15.0-118.128
  • 5.15.0-119.129
  • 5.15.0-121.131
  • 5.15.0-122.132
  • 5.15.0-124.134
  • 5.15.0-125.135
  • 5.15.0-127.137
  • 5.15.0-130.140
  • 5.15.0-126.136
  • 5.15.0-131.141
  • 5.15.0-128.138
  • 5.15.0-133.144
  • 5.15.0-134.145
  • 5.15.0-135.146
  • 5.15.0-136.147
  • 5.15.0-138.148
  • 5.15.0-139.149
  • 5.15.0-140.150
  • 5.15.0-141.151
  • 5.15.0-142.152
  • 5.15.0-143.153
  • 5.15.0-144.157
  • 5.15.0-151.161
  • 5.15.0-152.162
  • 5.15.0-153.163
  • 5.15.0-156.166
  • 5.15.0-157.167
  • 5.15.0-160.170
  • 5.15.0-161.171
  • 5.15.0-163.173
  • 5.15.0-164.174
  • 5.15.0-168.178
  • 5.15.0-170.180
  • 5.15.0-171.181
  • 5.15.0-173.183
  • 5.15.0-174.184
Ubuntu 22.04 AWS Released
83 kernels
  • 5.15.0-1005.7
  • 5.15.0-1008.10
  • 5.15.0-1011.14
  • 5.15.0-1013.17
  • 5.15.0-1015.19
  • 5.15.0-1017.21
  • 5.15.0-1009.11
  • 5.15.0-1020.24
  • 5.15.0-1021.25
  • 5.15.0-1022.26
  • 5.15.0-1023.27
  • 5.15.0-1026.30
  • 5.15.0-1004.6
  • 5.15.0-1014.18
  • 5.15.0-1018.22
  • 5.15.0-1024.29
  • 5.15.0-1027.31
  • 5.15.0-1028.32
  • 5.15.0-1030.34
  • 5.15.0-1031.35
  • 5.15.0-1033.37
  • 5.15.0-1034.38
  • 5.15.0-1035.39
  • 5.15.0-1036.40
  • 5.15.0-1032.36
  • 5.15.0-1037.41
  • 5.15.0-1038.43
  • 5.15.0-1039.44
  • 5.15.0-1040.45
  • 5.15.0-1042.47
  • 5.15.0-1043.48
  • 5.15.0-1044.49
  • 5.15.0-1045.50
  • 5.15.0-1047.52
  • 5.15.0-1048.53
  • 5.15.0-1049.54
  • 5.15.0-1050.55
  • 5.15.0-1051.56
  • 5.15.0-1052.57
  • 5.15.0-1053.58
  • 5.15.0-1055.60
  • 5.15.0-1056.61
  • 5.15.0-1057.63
  • 5.15.0-1060.66
  • 5.15.0-1061.67
  • 5.15.0-1062.68
  • 5.15.0-1063.69
  • 5.15.0-1064.70
  • 5.15.0-1065.71
  • 5.15.0-1066.72
  • 5.15.0-1067.73
  • 5.15.0-1068.74
  • 5.15.0-1069.75
  • 5.15.0-1070.76
  • 5.15.0-1071.77
  • 5.15.0-1072.78
  • 5.15.0-1073.79
  • 5.15.0-1076.83
  • 5.15.0-1078.85
  • 5.15.0-1079.86
  • 5.15.0-1080.87
  • 5.15.0-1081.88
  • 5.15.0-1082.89
  • 5.15.0-1083.90
  • 5.15.0-1084.91
  • 5.15.0-1085.92
  • 5.15.0-1086.93
  • 5.15.0-1087.94
  • 5.15.0-1088.95
  • 5.15.0-1089.96
  • 5.15.0-1090.97
  • 5.15.0-1091.98
  • 5.15.0-1092.99
  • 5.15.0-1093.100
  • 5.15.0-1095.102
  • 5.15.0-1096.103
  • 5.15.0-1097.104
  • 5.15.0-1098.105
  • 5.15.0-1099.106
  • 5.15.0-1100.107
  • 5.15.0-1101.108
  • 5.15.0-1103.110
  • 5.15.0-1104.111
Ubuntu 22.04 Azure Released
74 kernels
  • 5.15.0-1005.6
  • 5.15.0-1007.8
  • 5.15.0-1010.12
  • 5.15.0-1012.15
  • 5.15.0-1014.17
  • 5.15.0-1017.20
  • 5.15.0-1008.9
  • 5.15.0-1019.24
  • 5.15.0-1020.25
  • 5.15.0-1021.26
  • 5.15.0-1022.27
  • 5.15.0-1003.4
  • 5.15.0-1013.16
  • 5.15.0-1023.29
  • 5.15.0-1029.36
  • 5.15.0-1024.30
  • 5.15.0-1034.41
  • 5.15.0-1035.42
  • 5.15.0-1036.43
  • 5.15.0-1037.44
  • 5.15.0-1038.45
  • 5.15.0-1039.46
  • 5.15.0-1040.47
  • 5.15.0-1041.48
  • 5.15.0-1042.49
  • 5.15.0-1045.52
  • 5.15.0-1046.53
  • 5.15.0-1047.54
  • 5.15.0-1049.56
  • 5.15.0-1044.51
  • 5.15.0-1050.57
  • 5.15.0-1051.59
  • 5.15.0-1052.60
  • 5.15.0-1053.61
  • 5.15.0-1054.62
  • 5.15.0-1056.64
  • 5.15.0-1057.65
  • 5.15.0-1058.66
  • 5.15.0-1059.67
  • 5.15.0-1060.69
  • 5.15.0-1061.70
  • 5.15.0-1063.72
  • 5.15.0-1064.73
  • 5.15.0-1066.75
  • 5.15.0-1067.76
  • 5.15.0-1068.77
  • 5.15.0-1070.79
  • 5.15.0-1071.80
  • 5.15.0-1072.81
  • 5.15.0-1073.82
  • 5.15.0-1074.83
  • 5.15.0-1075.84
  • 5.15.0-1078.87
  • 5.15.0-1079.88
  • 5.15.0-1081.90
  • 5.15.0-1082.91
  • 5.15.0-1084.93
  • 5.15.0-1086.95
  • 5.15.0-1087.96
  • 5.15.0-1088.97
  • 5.15.0-1089.98
  • 5.15.0-1090.99
  • 5.15.0-1091.100
  • 5.15.0-1092.101
  • 5.15.0-1094.103
  • 5.15.0-1095.104
  • 5.15.0-1096.105
  • 5.15.0-1097.106
  • 5.15.0-1098.107
  • 5.15.0-1101.110
  • 5.15.0-1102.111
  • 5.15.0-1099.108
  • 5.15.0-1103.112
  • 5.15.0-1109.118
Ubuntu 24.04 Released
43 kernels
  • 6.8.0-35.35
  • 6.8.0-38.38
  • 6.8.0-36.36
  • 6.8.0-39.39
  • 6.8.0-40.40
  • 6.8.0-41.41
  • 6.8.0-44.44
  • 6.8.0-45.45
  • 6.8.0-31.31
  • 6.8.0-47.47
  • 6.8.0-48.48
  • 6.8.0-49.49
  • 6.8.0-50.51
  • 6.8.0-51.52
  • 6.8.0-52.53
  • 6.8.0-54.56
  • 6.8.0-55.57
  • 6.8.0-53.55
  • 6.8.0-56.58
  • 6.8.0-57.59
  • 6.8.0-58.60
  • 6.8.0-59.61
  • 6.8.0-60.63
  • 6.8.0-62.65
  • 6.8.0-63.66
  • 6.8.0-64.67
  • 6.8.0-71.71
  • 6.8.0-78.78
  • 6.8.0-79.79
  • 6.8.0-84.84
  • 6.8.0-85.85
  • 6.8.0-83.83
  • 6.8.0-86.87
  • 6.8.0-87.88
  • 6.8.0-88.89
  • 6.8.0-90.91
  • 6.8.0-94.96
  • 6.8.0-100.100
  • 6.8.0-101.101
  • 6.8.0-106.106
  • 6.8.0-107.107
  • 6.8.0-110.110
  • 6.8.0-111.111
Ubuntu 24.04 AWS Planned