INFO: task syz.1.3500:18544 blocked for more than 143 seconds. Not tainted syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.3500 state:D stack:25784 pid:18544 tgid:18544 ppid:16388 task_flags:0x40004c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185 __down_write_common kernel/locking/rwsem.c:1317 [inline] __down_write kernel/locking/rwsem.c:1326 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591 mmap_write_lock include/linux/mmap_lock.h:312 [inline] exit_mmap+0x281/0xb20 mm/mmap.c:1288 __mmput+0x118/0x430 kernel/fork.c:1130 exit_mm+0x1da/0x2c0 kernel/exit.c:583 do_exit+0x658/0x2310 kernel/exit.c:961 do_group_exit+0x21c/0x2d0 kernel/exit.c:1114 __do_sys_exit_group kernel/exit.c:1125 [inline] __se_sys_exit_group kernel/exit.c:1123 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1123 x64_sys_call+0x2210/0x2210 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f77c258f749 RSP: 002b:00007ffd0d099ad8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f77c258f749 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffd0d099b3c R08: 000000190d099bcf R09: 00000000000927c0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000074 R13: 00000000000927c0 R14: 000000000005c57a R15: 00007ffd0d099b90 INFO: task syz.2.3505:18570 blocked for more than 143 seconds. Not tainted syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.3505 state:D stack:21280 pid:18570 tgid:18568 ppid:17487 task_flags:0x40054c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185 __down_write_common kernel/locking/rwsem.c:1317 [inline] __down_write kernel/locking/rwsem.c:1326 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591 mmap_write_lock include/linux/mmap_lock.h:312 [inline] exit_mmap+0x281/0xb20 mm/mmap.c:1288 __mmput+0x118/0x430 kernel/fork.c:1130 exit_mm+0x1da/0x2c0 kernel/exit.c:583 do_exit+0x658/0x2310 kernel/exit.c:961 do_group_exit+0x21c/0x2d0 kernel/exit.c:1114 get_signal+0x1285/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f19ead8f749 RSP: 002b:00007f19ebb490e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f19eafe6098 RCX: 00007f19ead8f749 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f19eafe6098 RBP: 00007f19eafe6090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f19eafe6128 R14: 00007ffe21cf0bd0 R15: 00007ffe21cf0cb8 INFO: task syz.3.3506:18572 blocked for more than 144 seconds. Not tainted syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.3506 state:D stack:25432 pid:18572 tgid:18572 ppid:16791 task_flags:0x40004c flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185 __down_write_common kernel/locking/rwsem.c:1317 [inline] __down_write kernel/locking/rwsem.c:1326 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591 mmap_write_lock include/linux/mmap_lock.h:312 [inline] exit_mmap+0x281/0xb20 mm/mmap.c:1288 __mmput+0x118/0x430 kernel/fork.c:1130 exit_mm+0x1da/0x2c0 kernel/exit.c:583 do_exit+0x658/0x2310 kernel/exit.c:961 do_group_exit+0x21c/0x2d0 kernel/exit.c:1114 __do_sys_exit_group kernel/exit.c:1125 [inline] __se_sys_exit_group kernel/exit.c:1123 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1123 x64_sys_call+0x2210/0x2210 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbd82b8f749 RSP: 002b:00007fffb6ab3da8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbd82b8f749 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fffb6ab3e0c R08: 0000000eb6ab3e9f R09: 00000000000927c0 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000058 R13: 00000000000927c0 R14: 000000000005c82c R15: 00007fffb6ab3e60 Showing all locks held in the system: 1 lock held by rcu_tasks_trace/29: #0: ffffffff8df42a10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{4:4}, at: rcu_tasks_one_gp+0xaf9/0xdf0 kernel/rcu/tasks.h:614 1 lock held by khungtaskd/31: #0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:4/60: #0: ffff88801a069948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801a069948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000211fb80 ((work_completion)(©->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000211fb80 ((work_completion)(©->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8df476c0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3816 3 locks held by kworker/u8:10/3483: #0: ffff88801a069948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801a069948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000bac7b80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000bac7b80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffffffff8f2f5608 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 2 locks held by getty/5592: #0: ffff888030d010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by kworker/u8:30/14575: 6 locks held by kworker/u8:32/14577: #0: ffff8880b893a7d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639 #1: ffff8880b8924448 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b8925f98 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x8ee/0xf30 kernel/time/timer.c:1117 #3: ffffffff99b00090 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x87/0x540 lib/debugobjects.c:818 #4: ffffffff8ddec888 (text_mutex){+.+.}-{4:4}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145 #5: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #5: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #5: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: ___pte_offset_map+0x29/0x250 mm/pgtable-generic.c:286 1 lock held by udevd/15374: #0: ffff88802589b358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962 1 lock held by udevd/15901: #0: ffff888025926358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962 1 lock held by udevd/16637: #0: ffff888025a5e358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962 1 lock held by syz-executor/17487: #0: ffff888076a45900 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline] #0: ffff888076a45900 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x281/0xb20 mm/mmap.c:1288 1 lock held by syz.1.3500/18544: #0: ffff88807836d900 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline] #0: ffff88807836d900 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x281/0xb20 mm/mmap.c:1288 1 lock held by syz.2.3505/18570: #0: ffff888076a46540 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline] #0: ffff888076a46540 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x281/0xb20 mm/mmap.c:1288 1 lock held by syz.3.3506/18572: #0: ffff88802970d900 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:312 [inline] #0: ffff88802970d900 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x281/0xb20 mm/mmap.c:1288 1 lock held by syz.6.4589/22574: 1 lock held by syz.5.4630/22708: #0: ffffffff99d4f2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: ip_set_nfnl_get_byindex+0x67/0x230 net/netfilter/ipset/ip_set_core.c:909 1 lock held by syz.5.4630/22709: #0: ffffffff99d4f2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline] #0: ffffffff99d4f2f8 (nfnl_subsys_ipset){+.+.}-{4:4}, at: nfnetlink_rcv_msg+0x9dc/0x1130 net/netfilter/nfnetlink.c:295 2 locks held by syz.0.4635/22725: #0: ffffffff8f2f5608 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8f2f5608 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436 #1: ffffffff8df477f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8df477f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:956 1 lock held by syz.0.4635/22728: #0: ffffffff8f2f5608 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f2f5608 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6964 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf3c/0xf80 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 11348 Comm: kworker/u8:18 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker RIP: 0010:check_preemption_disabled+0x45/0x120 lib/smp_processor_id.c:53 Code: 92 2d 07 65 8b 0d 1b 92 2d 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d fb 91 2d 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b <41> 5e 41 5f 5d c3 cc cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 RSP: 0018:ffffc9000b2d7828 EFLAGS: 00000082 RAX: 0000000000000001 RBX: 0000000000000202 RCX: ecb238b487c63500 RDX: 0000000000000000 RSI: ffffffff8d780994 RDI: ffffffff8bbfc660 RBP: ffffc9000b2d7a30 R08: 0000000000000004 R09: 0000000000000004 R10: ffffc9000b2d7984 R11: fffff5200165af32 R12: ffff888024820b88 R13: ffffffff8636928c R14: ffff888024820f08 R15: ffff888029231e80 FS: 0000000000000000(0000) GS:ffff8881261b1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8e627b42f8 CR3: 0000000074c1e000 CR4: 00000000003526f0 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline] lock_release+0xb3/0x3b0 kernel/locking/lockdep.c:5888 up_read+0x16/0x20 kernel/locking/rwsem.c:1632 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:35 [inline] wg_packet_handshake_send_worker+0x17c/0x320 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 lec0: NETDEV WATCHDOG: CPU: 0: transmit queue 0 timed out 5070 ms lec:lec_tx_timeout: lec0