INFO: task syz-executor:5829 blocked for more than 143 seconds. Not tainted 6.4.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:10808 pid:5829 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5343 [inline] __schedule+0x6af/0x9c0 kernel/sched/core.c:6669 schedule+0x68/0xc0 kernel/sched/core.c:6745 schedule_preempt_disabled+0x32/0x60 kernel/sched/core.c:6804 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x449/0x970 kernel/locking/mutex.c:747 del_device_store+0x7d/0x1a0 drivers/net/netdevsim/bus.c:209 kernfs_fop_write_iter+0x217/0x2b0 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:1868 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x3ae/0x650 fs/read_write.c:584 ksys_write+0xc6/0x180 fs/read_write.c:637 do_syscall_64+0x46/0xc0 entry_SYSCALL_64_after_hwframe+0x73/0xdd RIP: 0033:0x7fcf0257d2c0 RSP: 002b:00007ffd100c7c18 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fcf0257d2c0 RDX: 0000000000000001 RSI: 00007ffd100c7c40 RDI: 0000000000000005 RBP: 00007fcf025f2876 R08: 0000000000000001 R09: 00007ffd100c7a47 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000001 R13: 00007ffd100c7c40 R14: 00007fcf03264620 R15: 0000000000000003 Showing all locks held in the system: 5 locks held by kworker/u4:1/12: #0: ffff888101643d38 ((wq_completion)netns){....}-{0:0}, at: process_one_work+0x26a/0x740 kernel/workqueue.c:2378 #1: ffffc9000006be60 (net_cleanup_work){....}-{0:0}, at: process_one_work+0x294/0x740 kernel/workqueue.c:2380 #2: ffffffff85b3f498 (pernet_ops_rwsem){....}-{3:3}, at: cleanup_net+0x4a/0x5e0 net/core/net_namespace.c:576 #3: ffffffff85b41418 (rtnl_mutex){....}-{3:3}, at: default_device_exit_batch+0x43/0x370 net/core/dev.c:11377 #4: ffffffff857feab8 (rcu_state.exp_mutex){....}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:293 [inline] #4: ffffffff857feab8 (rcu_state.exp_mutex){....}-{3:3}, at: synchronize_rcu_expedited+0x3a0/0x700 kernel/rcu/tree_exp.h:992 1 lock held by rcu_tasks_kthre/13: #0: ffffffff857fd9d8 (rcu_tasks.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_one_gp kernel/rcu/tasks.h:518 [inline] #0: ffffffff857fd9d8 (rcu_tasks.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_kthread+0x9c/0x460 kernel/rcu/tasks.h:563 1 lock held by rcu_tasks_trace/14: #0: ffffffff857fdcb8 (rcu_tasks_trace.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_one_gp kernel/rcu/tasks.h:518 [inline] #0: ffffffff857fdcb8 (rcu_tasks_trace.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_kthread+0x9c/0x460 kernel/rcu/tasks.h:563 2 locks held by kworker/1:0/22: 1 lock held by khungtaskd/28: #0: ffffffff857fd8b0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 arch/x86/kernel/nmi.c:311 5 locks held by kworker/1:3/3997: 2 locks held by getty/4411: #0: ffff88811713d898 (&tty->ldisc_sem){....}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x50 drivers/tty/tty_ldisc.c:243 #1: ffffc9000d2c72f0 (&ldata->atomic_read_lock){....}-{3:3}, at: n_tty_read+0x319/0xf00 drivers/tty/n_tty.c:2176 6 locks held by syz-executor/5819: #0: ffff888118f67450 (sb_writers#8){....}-{0:0}, at: ksys_write+0xc6/0x180 fs/read_write.c:637 #1: ffff8881192e5e88 (&of->mutex){....}-{3:3}, at: kernfs_fop_write_iter+0x12e/0x2b0 fs/kernfs/file.c:325 #2: ffff888101f7d740 (kn->active#55){....}-{0:0}, at: kernfs_fop_write_iter+0x137/0x2b0 fs/kernfs/file.c:326 #3: ffffffff859e02d0 (nsim_bus_dev_list_lock){....}-{3:3}, at: del_device_store+0x7d/0x1a0 drivers/net/netdevsim/bus.c:209 #4: ffff8881193bc0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #4: ffff8881193bc0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff8881193bc0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x6b/0x3a0 drivers/base/dd.c:1292 #5: ffffffff85b3f498 (pernet_ops_rwsem){....}-{3:3}, at: unregister_netdevice_notifier+0x34/0x1c0 net/core/dev.c:1757 4 locks held by syz-executor/5829: #0: ffff888118f67450 (sb_writers#8){....}-{0:0}, at: ksys_write+0xc6/0x180 fs/read_write.c:637 #1: ffff888119254088 (&of->mutex){....}-{3:3}, at: kernfs_fop_write_iter+0x12e/0x2b0 fs/kernfs/file.c:325 #2: ffff888101f7d740 (kn->active#55){....}-{0:0}, at: kernfs_fop_write_iter+0x137/0x2b0 fs/kernfs/file.c:326 #3: ffffffff859e02d0 (nsim_bus_dev_list_lock){....}-{3:3}, at: del_device_store+0x7d/0x1a0 drivers/net/netdevsim/bus.c:209 1 lock held by syz-executor/6566: #0: ffffffff85b41418 (rtnl_mutex){....}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff85b41418 (rtnl_mutex){....}-{3:3}, at: rtnetlink_rcv_msg+0x5db/0x750 net/core/rtnetlink.c:6392 1 lock held by syz-executor/6569: #0: ffffffff85b41418 (rtnl_mutex){....}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff85b41418 (rtnl_mutex){....}-{3:3}, at: rtnetlink_rcv_msg+0x5db/0x750 net/core/rtnetlink.c:6392 1 lock held by syz-executor/6572: #0: ffffffff85b41418 (rtnl_mutex){....}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff85b41418 (rtnl_mutex){....}-{3:3}, at: rtnetlink_rcv_msg+0x5db/0x750 net/core/rtnetlink.c:6392 1 lock held by syz-executor/6575: #0: ffffffff85b41418 (rtnl_mutex){....}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff85b41418 (rtnl_mutex){....}-{3:3}, at: rtnetlink_rcv_msg+0x5db/0x750 net/core/rtnetlink.c:6392 2 locks held by syz.1.75/6650: #0: ffff888161ae69a8 (&nft_net->commit_mutex){....}-{3:3}, at: nf_tables_valid_genid+0x45/0x90 net/netfilter/nf_tables_api.c:9788 #1: ffffffff857feab8 (rcu_state.exp_mutex){....}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #1: ffffffff857feab8 (rcu_state.exp_mutex){....}-{3:3}, at: synchronize_rcu_expedited+0x240/0x700 kernel/rcu/tree_exp.h:992 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.4.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xf4/0x180 lib/dump_stack.c:106 nmi_cpu_backtrace+0x234/0x250 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0xf2/0x210 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0x81f/0x860 kernel/hung_task.c:379 kthread+0x113/0x140 kernel/kthread.c:379 ret_from_fork+0x29/0x50 arch/x86/entry/entry_64.S:308 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3997 Comm: kworker/1:3 Not tainted 6.4.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:200 Code: 89 fb e8 23 00 00 00 48 8b 3d 64 e3 97 04 48 89 de 5b e9 03 23 2b 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0d a0 10 cb 7e 65 8b 15 a1 10 cb RSP: 0018:ffffc900000d0850 EFLAGS: 00000206 RAX: ffff888105ef5280 RBX: ffffc900000d08f0 RCX: ffff888105ef5280 RDX: 0000000080000101 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff83c2e56f R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8881795d1b00 R13: ffff888117784700 R14: 0000000000000000 R15: ffff8881795d1b00 FS: 0000000000000000(0000) GS:ffff888237d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200000c0 CR3: 000000011951e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire+0x5/0x40 include/linux/rcupdate.h:326 rcu_read_lock include/linux/rcupdate.h:773 [inline] ip_route_output_key_hash net/ipv4/route.c:2640 [inline] __ip_route_output_key include/net/route.h:134 [inline] ip_route_output_flow+0x9f/0x140 net/ipv4/route.c:2869 ip_route_output_key include/net/route.h:150 [inline] ip_route_me_harder+0x372/0x6b0 net/ipv4/netfilter.c:52 synproxy_send_tcp+0x178/0x240 net/netfilter/nf_synproxy_core.c:431 synproxy_send_client_synack+0x304/0x330 net/netfilter/nf_synproxy_core.c:484 nft_synproxy_eval_v4+0x184/0x1d0 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x170/0x370 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x28a/0xab0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x144/0x170 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:143 [inline] nf_hook_slow+0x54/0x140 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:258 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x12e/0x170 net/ipv4/ip_input.c:254 NF_HOOK include/linux/netfilter.h:303 [inline] ip_rcv+0x55/0x130 net/ipv4/ip_input.c:569 __netif_receive_skb_one_core net/core/dev.c:5491 [inline] __netif_receive_skb+0xe4/0x210 net/core/dev.c:5605 process_backlog+0x13a/0x210 net/core/dev.c:5933 __napi_poll+0x44/0x320 net/core/dev.c:6496 napi_poll net/core/dev.c:6563 [inline] net_rx_action+0x1f7/0x4a0 net/core/dev.c:6696 __do_softirq+0x110/0x2fa kernel/softirq.c:553 do_softirq+0x86/0xf0 kernel/softirq.c:454 __local_bh_enable_ip+0x69/0x70 kernel/softirq.c:381 neigh_periodic_work+0x387/0x400 net/core/neighbour.c:1006 process_one_work+0x319/0x740 kernel/workqueue.c:2405 worker_thread+0x328/0x580 kernel/workqueue.c:2552 kthread+0x113/0x140 kernel/kthread.c:379 ret_from_fork+0x29/0x50 arch/x86/entry/entry_64.S:308