IPVS: rr: UDP 224.0.0.2:0 - no destination available ================================================================== BUG: KCSAN: data-race in kick_pool / wq_worker_running read-write to 0xffff888237c2a3a4 of 4 bytes by task 4123 on cpu 0: wq_worker_running+0x95/0x120 kernel/workqueue.c:1406 schedule_timeout+0xb7/0x170 kernel/time/sleep_timeout.c:99 schedule_timeout_uninterruptible kernel/time/sleep_timeout.c:158 [inline] msleep+0x50/0x90 kernel/time/sleep_timeout.c:318 nsim_fib6_rt_add drivers/net/netdevsim/fib.c:693 [inline] nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:759 [inline] nsim_fib6_event drivers/net/netdevsim/fib.c:856 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:889 [inline] nsim_fib_event_work+0x42e6/0x4790 drivers/net/netdevsim/fib.c:1493 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3346 worker_thread+0x582/0x770 kernel/workqueue.c:3427 kthread+0x489/0x510 kernel/kthread.c:463 ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 read to 0xffff888237c2a3a4 of 4 bytes by interrupt on cpu 1: need_more_worker kernel/workqueue.c:940 [inline] kick_pool+0x49/0x2d0 kernel/workqueue.c:1246 __queue_work+0x897/0xae0 kernel/workqueue.c:2342 queue_work_on+0xd1/0x160 kernel/workqueue.c:2392 wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:171 [inline] wg_packet_create_data drivers/net/wireguard/send.c:320 [inline] wg_packet_send_staged_packets+0xa3c/0xce0 drivers/net/wireguard/send.c:388 wg_xmit+0x5c7/0x6b0 drivers/net/wireguard/device.c:218 __netdev_start_xmit include/linux/netdevice.h:5248 [inline] netdev_start_xmit include/linux/netdevice.h:5257 [inline] xmit_one net/core/dev.c:3845 [inline] dev_hard_start_xmit+0x125/0x3e0 net/core/dev.c:3861 __dev_queue_xmit+0x10bf/0x1fd0 net/core/dev.c:4763 dev_queue_xmit include/linux/netdevice.h:3365 [inline] neigh_connected_output+0x253/0x2c0 net/core/neighbour.c:1624 neigh_output include/net/neighbour.h:547 [inline] ip6_finish_output2+0xa5f/0xd10 net/ipv6/ip6_output.c:136 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline] ip6_finish_output+0x3a4/0x540 net/ipv6/ip6_output.c:220 NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip6_output+0x10a/0x250 net/ipv6/ip6_output.c:247 dst_output include/net/dst.h:464 [inline] NF_HOOK include/linux/netfilter.h:318 [inline] ndisc_send_skb+0x50f/0x760 net/ipv6/ndisc.c:512 ndisc_send_rs+0x2e7/0x360 net/ipv6/ndisc.c:722 addrconf_rs_timer+0x1e5/0x310 net/ipv6/addrconf.c:4037 call_timer_fn+0x3b/0x290 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2373 [inline] __run_timer_base+0x415/0x610 kernel/time/timer.c:2385 run_timer_base kernel/time/timer.c:2394 [inline] run_timer_softirq+0x31/0x70 kernel/time/timer.c:2404 handle_softirqs+0xba/0x290 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x3a/0xc0 kernel/softirq.c:723 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 kcsan_setup_watchpoint+0x415/0x430 kernel/kcsan/core.c:705 avtab_search_node+0x122/0x2b0 security/selinux/ss/avtab.c:188 context_struct_compute_av+0x332/0xaa0 security/selinux/ss/services.c:664 security_compute_av+0x346/0xa10 security/selinux/ss/services.c:1177 avc_compute_av+0x5a/0x3e0 security/selinux/avc.c:991 avc_perm_nonode+0x5e/0xe0 security/selinux/avc.c:1116 avc_has_perm_noaudit+0x156/0x200 security/selinux/avc.c:1159 avc_has_perm+0x60/0x180 security/selinux/avc.c:1194 selinux_socket_unix_may_send+0x102/0x130 security/selinux/hooks.c:5221 security_unix_may_send+0x40/0x80 security/security.c:4619 unix_dgram_sendmsg+0x828/0xfd0 net/unix/af_unix.c:2251 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg+0x145/0x180 net/socket.c:733 sock_write_iter+0x1a7/0x1f0 net/socket.c:1186 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x52a/0x960 fs/read_write.c:686 ksys_write+0xda/0x1a0 fs/read_write.c:738 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x40/0x50 fs/read_write.c:746 x64_sys_call+0x2847/0x3000 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd8/0x2a0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000000 -> 0x00000001 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 18538 Comm: udevd Tainted: G W syzkaller #0 PREEMPT(voluntary) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 ================================================================== IPVS: rr: UDP 224.0.0.2:0 - no destination available IPVS: rr: UDP 224.0.0.2:0 - no destination available IPVS: rr: UDP 224.0.0.2:0 - no destination available IPVS: rr: UDP 224.0.0.2:0 - no destination available IPVS: rr: UDP 224.0.0.2:0 - no destination available IPVS: rr: UDP 224.0.0.2:0 - no destination available IPVS: rr: UDP 224.0.0.2:0 - no destination available IPVS: rr: UDP 224.0.0.2:0 - no destination available IPVS: rr: UDP 224.0.0.2:0 - no destination available