XPost: linux.debian.bugs.dist   
   From: jpenn@bentonvillek12.org   
      
   Package: src:linux   
   Version: 6.17.13-1   
   Severity: normal   
      
   Dear Maintainer,   
      
   This is an OpenVPN server serving primarially TCP clients (but also some   
   UDP clients). As I write this there are 1161 TCP clients and 74 UDP   
   clients. It is running debian testing in order to have ovpn-dco-offload   
   functionality for TCP connections. We observe that under hevy load (in   
   terms of connections count, not really under much load in terms of   
   bandwidth) this server will become locked up from time to time and the   
   graphical console will become completely non-responsive. When this   
   happens we reset the VM and things continue running normally. I   
   attempted to monitor the system using dmesg and notice that I am getting   
   some interesting messages about "BUG: kernel NULL pointer dereference"   
   that mention the ovpn module, leading me to believe that this is a   
   kernel bug in that module. Unfortunatly this issue only occours when the   
   server has many connections, and that is only happening because most of   
   my users are working from home today due to weather. This gives me a   
   rather small window of reproducability but if there is any additional   
   information I can provide let me know.   
   -- Package-specific info:   
   ** Version:   
   Linux version 6.17.13+deb14-amd64 (debian-kernel@lists.debian.org)   
   (x86_64-linux-gnu-gcc-15 (Debian 15.2.0-12) 15.2.0, GNU ld (GNU Binutils   
   for Debian) 2.45.50.20251209) #1 SMP PREEMPT_DYNAMIC Debian 6.17.13-1   
   (2025-12-20)   
      
   ** Command line:   
   BOOT_IMAGE=/boot/vmlinuz-6.17.13+deb14-amd64   
   root=UUID=f00f1200-b8d8-4432-bb0b-593a5ab9075a ro quiet   
      
   ** Tainted: D (128)   
   * kernel died recently, i.e. there was an OOPS or BUG   
      
   ** Kernel log:   
   [ 709.018150] tun1: deleting peer with id 719, reason 1   
   [ 709.056997] tun1: deleting peer with id 1055, reason 1   
   [ 711.054524] tun1: deleting peer with id 201, reason 2   
   [ 711.055070] BUG: kernel NULL pointer dereference, address:   
   0000000000000020   
   [ 711.055096] #PF: supervisor write access in kernel mode   
   [ 711.055429] #PF: error_code(0x0002) - not-present page   
   [ 711.055656] PGD 0 P4D 0   
   [ 711.055824] Oops: Oops: 0002 [#1] SMP NOPTI   
   [ 711.055991] CPU: 12 UID: 0 PID: 527 Comm: kworker/12:2 Not tainted   
   6.17.13+deb14-amd64 #1 PREEMPT(lazy) Debian 6.17.13-1   
   [ 711.056154] Hardware name: Red Hat KVM, BIOS   
   edk2-20221207gitfff6d81270b5-9.el9_2 12/07/2022   
   [ 711.056333] Workqueue: events ovpn_peer_keepalive_work [ovpn]   
   [ 711.056524] RIP: 0010:ovpn_tcp_socket_detach+0x61/0x80 [ovpn]   
   [ 711.056695] Code: 01 00 00 48 8b 83 b8 01 00 00 48 89 85 c0 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 98 02 00 00 00 00 00 00 5b 5d c3 cc cc cc cc   
   [ 711.056986] RSP: 0018:ffffd3988153fdb8 EFLAGS: 00010246   
   [ 711.057136] RAX: 0000000000000000 RBX: ffff8e65873a5400 RCX:   
   0000000000000004   
   [ 711.057314] RDX: ffffffff92d6d660 RSI: 0000000000000068 RDI:   
   ffff8e65873a5568   
   [ 711.057475] RBP: ffff8e6590fb4280 R08: 0000000000000000 R09:   
   0000000000000101   
   [ 711.057644] R10: 0000000000000000 R11: ffffffff93a080e0 R12:   
   000000006978de32   
   [ 711.057794] R13: 0000000000000001 R14: ffff8e65839c1aa8 R15:   
   0000000000000000   
   [ 711.057940] FS: 0000000000000000(0000) GS:ffff8e695b708000(0000)   
   knlGS:0000000000000000   
   [ 711.058087] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033   
   [ 711.058246] CR2: 0000000000000020 CR3: 000000010862d001 CR4:   
   00000000007726f0   
   [ 711.058412] PKRU: 55555554   
   [ 711.058584] Call Trace:   
   [ 711.058739]    
   [ 711.058892] ovpn_socket_release+0x165/0x1a0 [ovpn]   
   [ 711.059048] unlock_ovpn+0x48/0x80 [ovpn]   
   [ 711.059199] ovpn_peer_keepalive_work+0xf3/0x1b0 [ovpn]   
   [ 711.059360] ? __schedule+0x464/0xd20   
   [ 711.059557] process_one_work+0x18f/0x350   
   [ 711.059740] worker_thread+0x25a/0x3a0   
   [ 711.059889] ? __pfx_worker_thread+0x10/0x10   
   [ 711.060046] kthread+0xfc/0x240   
   [ 711.060203] ? __pfx_kthread+0x10/0x10   
   [ 711.060358] ? __pfx_kthread+0x10/0x10   
   [ 711.060559] ret_from_fork+0x194/0x1c0   
   [ 711.060801] ? __pfx_kthread+0x10/0x10   
   [ 711.061019] ret_from_fork_asm+0x1a/0x30   
   [ 711.061269]    
   [ 711.061494] Modules linked in: intel_rapl_msr intel_rapl_common   
   intel_uncore_frequency_common isst_if_mbox_msr isst_if_common ovpn   
   ip6_udp_tunnel udp_tunnel skx_edac_common nfit libnvdimm kvm_intel kvm   
   binfmt_misc irqbypass ghash_clmulni_intel aesni_intel rapl nls_ascii   
   nls_cp437 vfat fat qxl drm_ttm_helper ttm drm_exec pcspkr drm_client_lib   
   sg drm_kms_helper button evdev joydev 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 libahci xhci_pci libata xhci_hcd iTCO_wdt   
   intel_pmc_bxt iTCO_vendor_support watchdog psmouse usbcore scsi_mod   
   e1000 serio_raw i2c_i801 lpc_ich scsi_common usb_common i2c_smbus   
   [ 711.062827] CR2: 0000000000000020   
   [ 711.063051] ---[ end trace 0000000000000000 ]---   
      
   [continued in next message]   
      
   --- SoupGate-Win32 v1.05   
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