INFO: task syz.4.5070:16288 blocked for more than 144 seconds. Not tainted 6.15.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.5070 state:D stack:28440 pid:16288 tgid:16288 ppid:6237 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:746 tty_release_struct+0xad/0xe0 drivers/tty/tty_io.c:1700 tty_release+0xe2d/0x1430 drivers/tty/tty_io.c:1861 __fput+0x3ff/0xb70 fs/file_table.c:465 task_work_run+0x14d/0x240 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f01aa58e969 RSP: 002b:00007fff7e8b1568 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00000000000510ba RCX: 00007f01aa58e969 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f01aa7b7ba0 R08: 0000000000000001 R09: 000000027e8b185f R10: 00007f01aa400000 R11: 0000000000000246 R12: 00007f01aa7b5fac R13: 00007f01aa7b5fa0 R14: ffffffffffffffff R15: 00007fff7e8b1680 Showing all locks held in the system: 1 lock held by kthreadd/2: 1 lock held by kworker/R-kvfre/6: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 3 locks held by kworker/0:0/9: 3 locks held by kworker/0:1/10: #0: ffff88805de99948 ((wq_completion)wg-kex-wg0#4){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900000f7d18 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88806f4e0d20 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_begin_session+0x30/0xe80 drivers/net/wireguard/noise.c:822 3 locks held by kworker/u8:0/12: 4 locks held by kworker/u8:1/13: 1 lock held by kworker/R-mm_pe/14: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 4 locks held by kworker/1:0/24: #0: ffff88805de99948 ((wq_completion)wg-kex-wg0#4){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900001e7d18 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88805d4b1308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x880 drivers/net/wireguard/noise.c:598 #3: ffff88806f4e0d20 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x880 drivers/net/wireguard/noise.c:632 1 lock held by khungtaskd/31: #0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 1 lock held by kworker/R-write/33: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 2 locks held by kworker/u8:3/52: 4 locks held by kworker/1:1/79: 4 locks held by kworker/u8:4/81: 3 locks held by kswapd0/89: 1 lock held by kworker/1:2/911: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 2 locks held by kworker/0:2/972: 4 locks held by kworker/u8:7/1147: 1 lock held by kworker/R-dm_bu/2808: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 1 lock held by kworker/R-bat_e/3394: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 3 locks held by kworker/u8:8/3468: 4 locks held by kworker/u8:11/3512: 4 locks held by kworker/u8:13/3593: 3 locks held by syslogd/5172: 2 locks held by dhcpcd/5483: 2 locks held by getty/5568: #0: ffff88803254a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5802: 3 locks held by kworker/1:3/6098: 5 locks held by kworker/1:4/6207: 1 lock held by syz-executor/6223: 2 locks held by syz-executor/6228: 1 lock held by syz-executor/6231: 1 lock held by kworker/R-wg-cr/6257: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 1 lock held by kworker/R-wg-cr/6258: 1 lock held by kworker/R-wg-cr/6262: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 1 lock held by kworker/R-wg-cr/6265: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 1 lock held by kworker/R-wg-cr/6266: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 1 lock held by kworker/R-wg-cr/6276: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 1 lock held by kworker/R-wg-cr/6277: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 1 lock held by kworker/R-wg-cr/6279: 1 lock held by kworker/R-wg-cr/6280: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 1 lock held by kworker/R-wg-cr/6281: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3529 1 lock held by kworker/R-wg-cr/6282: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 4 locks held by kworker/0:4/6311: 3 locks held by kworker/0:5/6318: 2 locks held by kworker/1:5/6383: 4 locks held by kworker/1:6/6384: #0: ffff8880367b6948 ((wq_completion)wg-kex-wg0#2){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000449fd18 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888065a65308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x880 drivers/net/wireguard/noise.c:598 #3: ffff888036303ea8 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x880 drivers/net/wireguard/noise.c:632 3 locks held by kworker/1:7/6446: 3 locks held by kworker/0:6/6449: 3 locks held by kworker/0:7/6450: 1 lock held by kworker/R-bond1/10852: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 1 lock held by kworker/R-bond1/11759: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 1 lock held by syz.4.5070/16288: #0: ffffffff8f0a5f28 (tty_mutex){+.+.}-{4:4}, at: tty_release_struct+0xad/0xe0 drivers/tty/tty_io.c:1700 3 locks held by kworker/0:8/16296: 1 lock held by kworker/u8:2/16297: #0: ffffffff8e2770c8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6207 Comm: kworker/1:4 Not tainted 6.15.0-rc5-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:check_preemption_disabled+0x16/0xe0 lib/smp_processor_id.c:16 Code: ff 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 54 55 53 48 83 ec 08 65 8b 1d 85 34 37 08 65 8b 05 7a 34 37 08 ff ff ff 7f 74 0f 48 83 c4 08 89 d8 5b 5d 41 5c c3 cc cc cc cc RSP: 0018:ffffc90000a08490 EFLAGS: 00000286 RAX: 0000000080000102 RBX: 0000000000000001 RCX: ffffffff8a1d88fb RDX: 0000000000000001 RSI: ffffffff8bf481e0 RDI: ffffffff8bf48220 RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001 R13: ffffc90000a087e0 R14: 0000000000000000 R15: ffff888028a6e4b8 FS: 0000000000000000(0000) GS:ffff888124adf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555953d35c8 CR3: 000000005f1dc000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:736 rcu_read_lock_held_common kernel/rcu/update.c:109 [inline] rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349 __find_rr_leaf+0x36c/0xe00 net/ipv6/route.c:834 find_rr_leaf net/ipv6/route.c:890 [inline] rt6_select net/ipv6/route.c:934 [inline] fib6_table_lookup+0x57c/0xa30 net/ipv6/route.c:2230 ip6_pol_route+0x1cc/0x1230 net/ipv6/route.c:2266 pol_lookup_func include/net/ip6_fib.h:616 [inline] fib6_rule_lookup+0x536/0x720 net/ipv6/fib6_rules.c:120 ip6_route_input_lookup net/ipv6/route.c:2335 [inline] ip6_route_input+0x662/0xc00 net/ipv6/route.c:2631 ip6_rcv_finish_core.constprop.0+0x1a0/0x5d0 net/ipv6/ip6_input.c:66 ip6_rcv_finish net/ipv6/ip6_input.c:77 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] ipv6_rcv+0x1e8/0x680 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:5887 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6000 process_backlog+0x442/0x15e0 net/core/dev.c:6352 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7324 napi_poll net/core/dev.c:7388 [inline] net_rx_action+0xa97/0x1010 net/core/dev.c:7510 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579 do_softirq kernel/softirq.c:480 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:467 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:407 neigh_periodic_work+0x768/0xcd0 net/core/neighbour.c:966 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 net_ratelimit: 24348 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:23:8f:cd:76:07, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:23:8f:cd:76:07, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:23:8f:cd:76:07, vlan:0) net_ratelimit: 23848 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:23:8f:cd:76:07, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:be:23:8f:cd:76:07, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)