On 2/1/2026 10:23 AM, Salvatore Bonaccorso wrote:
John in Debian you should soon available 6.18.8-1 and please do test
as well 6.19~rc6-1~exp1 from experimental (or 6.19~rc7-1~exp1 once it
passes).
Regards,
Salvatore
From Antonio Quartulli's email I see that there is likely a fix in
progress for this, but I figured I would go ahead and try with the
6.19~rc6-1~exp1 kernel just in-case that provided any useful
information. The issue does occur on that newer kernel version.
$ uname -a
Linux OpenVPN 6.19-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.19~rc6-1~exp1
(2026-01-23) x86_64 GNU/Linux
$ dmesg
...
[ 990.147725] tun1: deleting peer with id 1465, reason 1
[ 990.244257] tun1: deleting peer with id 34, reason 2
[ 990.244295] tun1: deleting peer with id 866, reason 2
[ 990.262672] BUG: kernel NULL pointer dereference, address:
0000000000000020
[ 990.262704] #PF: supervisor write access in kernel mode
[ 990.262721] #PF: error_code(0x0002) - not-present page
[ 990.262731] PGD 0 P4D 0
[ 990.262740] Oops: Oops: 0002 [#1] SMP NOPTI
[ 990.262758] CPU: 6 UID: 0 PID: 35801 Comm: kworker/6:2 Not tainted
6.19-amd64 #1 PREEMPT(lazy) Debian 6.19~rc6-1~exp1
[ 990.262777] Hardware name: Red Hat KVM, BIOS
edk2-20221207gitfff6d81270b5-9.el9_2 12/07/2022
[ 990.262792] Workqueue: events ovpn_peer_keepalive_work [ovpn]
[ 990.262822] RIP: 0010:ovpn_tcp_socket_detach+0x61/0x80 [ovpn]
[ 990.262837] Code: 01 00 00 48 8b 83 b8 01 00 00 48 89 85 c8 02 00 00
48 8b 83 c0 01 00 00 48 89 45 28 48 8b 85 20 01 00 00 48 8b 93 c8 01 00
00 <48> 89 50 20 48 c7 85 a0 02 00 00 00 00 00 00 5b 5d c3 cc cc cc cc
[ 990.262858] RSP: 0018:ffffd47b81cd3da8 EFLAGS: 00010246
[ 990.262868] RAX: 0000000000000000 RBX: ffff8df2e735a000 RCX:
0000000000000001
[ 990.262888] RDX: ffffffff8dd81200 RSI: 0000000000000069 RDI:
ffff8df2e735a168
[ 990.262901] RBP: ffff8df2e7b1df00 R08: 0000000000000246 R09:
0000000000000000
[ 990.262911] R10: ffff8df282b66780 R11: fffff520400ad980 R12:
000000006980b90c
[ 990.262920] R13: 0000000000000001 R14: ffff8df287968aa8 R15:
0000000000000000
[ 990.262930] FS: 0000000000000000(0000) GS:ffff8df35bb2c000(0000)
knlGS:0000000000000000
[ 990.262941] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 990.262952] CR2: 0000000000000020 CR3: 0000000010114003 CR4:
00000000007726f0
[ 990.262970] PKRU: 55555554
[ 990.262977] Call Trace:
[ 990.262989] <TASK>
[ 990.263003] ovpn_socket_release+0x165/0x1a0 [ovpn]
[ 990.263025] unlock_ovpn+0x48/0x80 [ovpn]
[ 990.263047] ovpn_peer_keepalive_work+0xf3/0x1c0 [ovpn]
[ 990.263065] process_one_work+0x192/0x350
[ 990.263100] worker_thread+0x25a/0x3a0
[ 990.263113] ? __pfx_worker_thread+0x10/0x10
[ 990.263123] kthread+0xfc/0x240
[ 990.263138] ? __pfx_kthread+0x10/0x10
[ 990.263146] ? __pfx_kthread+0x10/0x10
[ 990.263155] ret_from_fork+0x24d/0x290
[ 990.263182] ? __pfx_kthread+0x10/0x10
[ 990.263191] ret_from_fork_asm+0x1a/0x30
[ 990.263214] </TASK>
[ 990.263223] Modules linked in: ovpn ip6_udp_tunnel udp_tunnel
binfmt_misc nls_ascii nls_cp437 intel_rapl_msr intel_rapl_common vfat
fat intel_uncore_frequency_common isst_if_mbox_msr isst_if_common
skx_edac_common nfit libnvdimm kvm_intel kvm irqbypass
ghash_clmulni_intel aesni_intel rapl qxl pcspkr drm_ttm_helper ttm
drm_exec drm_client_lib drm_kms_helper button sg joydev evdev drm
configfs efi_pstore nfnetlink vsock_loopback
vmw_vsock_virtio_transport_common vmw_vsock_vmci_transport vsock
vmw_vmci efivarfs qemu_fw_cfg autofs4 ext4 crc16 mbcache jbd2
crc32c_cryptoapi hid_generic usbhid hid sr_mod sd_mod cdrom ahci
xhci_pci libahci xhci_hcd iTCO_wdt libata intel_pmc_bxt
iTCO_vendor_support watchdog psmouse usbcore scsi_mod serio_raw i2c_i801
lpc_ich e1000 i2c_smbus scsi_common usb_common
[ 990.263376] CR2: 0000000000000020
[ 990.263392] ---[ end trace 0000000000000000 ]---
[ 991.005331] RIP: 0010:ovpn_tcp_socket_detach+0x61/0x80 [ovpn]
[ 991.007709] Code: 01 00 00 48 8b 83 b8 01 00 00 48 89 85 c8 02 00 00
48 8b 83 c0 01 00 00 48 89 45 28 48 8b 85 20 01 00 00 48 8b 93 c8 01 00
00 <48> 89 50 20 48 c7 85 a0 02 00 00 00 00 00 00 5b 5d c3 cc cc cc cc
[ 991.008575] RSP: 0018:ffffd47b81cd3da8 EFLAGS: 00010246
[ 991.008984] RAX: 0000000000000000 RBX: ffff8df2e735a000 RCX:
0000000000000001
[ 991.009359] RDX: ffffffff8dd81200 RSI: 0000000000000069 RDI:
ffff8df2e735a168
[ 991.009725] RBP: ffff8df2e7b1df00 R08: 0000000000000246 R09:
0000000000000000
[ 991.010105] R10: ffff8df282b66780 R11: fffff520400ad980 R12:
000000006980b90c
[ 991.010467] R13: 0000000000000001 R14: ffff8df287968aa8 R15:
0000000000000000
[ 991.010833] FS: 0000000000000000(0000) GS:ffff8df35bb2c000(0000)
knlGS:0000000000000000
[ 991.011188] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 991.011543] CR2: 0000000000000020 CR3: 000000001b42c005 CR4:
00000000007726f0
[ 991.011922] PKRU: 55555554
[ 991.012270] note: kworker/6:2[35801] exited with irqs disabled
[ 991.906607] tun1: deleting peer with id 866, reason 1
[ 992.449819] tun1: deleting peer with id 1024, reason 1
[ 995.571185] tun1: deleting peer with id 34, reason 1
