INFO: task kworker/0:12:4455 blocked for more than 157 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:12 state:D stack:0 pid:4455 ppid:2 flags:0x00000008 Workqueue: ipv6_addrconf addrconf_dad_work Call trace: __switch_to+0x2f4/0x568 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5244 [inline] __schedule+0xddc/0x1b18 kernel/sched/core.c:6561 schedule+0xc4/0x170 kernel/sched/core.c:6637 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6696 __mutex_lock_common+0xad4/0x1f38 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 rtnl_lock+0x20/0x2c net/core/rtnetlink.c:74 addrconf_dad_work+0xbc/0x10e4 net/ipv6/addrconf.c:4131 process_one_work+0x7f4/0x13a8 kernel/workqueue.c:2292 worker_thread+0x8c8/0xfbc kernel/workqueue.c:2439 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850 INFO: task syz.3.131:4824 blocked for more than 157 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.131 state:D stack:0 pid:4824 ppid:4481 flags:0x00000001 Call trace: __switch_to+0x2f4/0x568 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5244 [inline] __schedule+0xddc/0x1b18 kernel/sched/core.c:6561 schedule+0xc4/0x170 kernel/sched/core.c:6637 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6696 __mutex_lock_common+0xad4/0x1f38 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 rtnl_lock net/core/rtnetlink.c:74 [inline] rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 netlink_rcv_skb+0x208/0x3c4 net/netlink/af_netlink.c:2511 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6168 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x60c/0x824 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x6e8/0x9b0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5b8/0x918 net/socket.c:2519 ___sys_sendmsg net/socket.c:2573 [inline] __sys_sendmsg+0x25c/0x320 net/socket.c:2602 __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg net/socket.c:2609 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2609 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 INFO: task syz.1.132:4826 blocked for more than 157 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.132 state:D stack:0 pid:4826 ppid:4472 flags:0x00000001 Call trace: __switch_to+0x2f4/0x568 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5244 [inline] __schedule+0xddc/0x1b18 kernel/sched/core.c:6561 schedule+0xc4/0x170 kernel/sched/core.c:6637 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6696 __mutex_lock_common+0xad4/0x1f38 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 rtnl_lock net/core/rtnetlink.c:74 [inline] rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 netlink_rcv_skb+0x208/0x3c4 net/netlink/af_netlink.c:2511 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6168 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x60c/0x824 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x6e8/0x9b0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5b8/0x918 net/socket.c:2519 ___sys_sendmsg net/socket.c:2573 [inline] __sys_sendmsg+0x25c/0x320 net/socket.c:2602 __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg net/socket.c:2609 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2609 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffff800015297870 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xbb4 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffff800015298090 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xbb4 kernel/rcu/tasks.h:517 3 locks held by kworker/1:1/24: #0: ffff0000d5de6d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265 #1: ffff80001c967c20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267 #2: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:74 1 lock held by khungtaskd/28: #0: ffff800015296f00 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349 2 locks held by getty/4077: #0: ffff0000d633a098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff8000207ab2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2ec/0xf9c drivers/tty/n_tty.c:2198 2 locks held by kworker/1:4/4442: #0: ffff0000c0021938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265 #1: ffff800021177c20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267 3 locks held by kworker/0:12/4455: #0: ffff0000d5de6d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265 #1: ffff8000212a7c20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267 #2: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:74 2 locks held by kworker/0:13/4456: #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265 #1: ffff8000212b7c20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267 2 locks held by kworker/0:17/4460: #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265 #1: ffff800021327c20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267 3 locks held by kworker/u4:8/4708: #0: ffff0000c002a138 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x6b4/0x13a8 kernel/workqueue.c:2265 #1: ffff800021ac7c20 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x6f8/0x13a8 kernel/workqueue.c:2267 #2: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:74 1 lock held by syz.0.17/4818: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:74 1 lock held by syz.2.130/4820: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:74 1 lock held by syz.4.21/4822: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz.3.131/4824: #0: ffff800017730fc8 ( rtnl_mutex){+.+.}-{3:3} , at: rtnl_lock net/core/rtnetlink.c:74 [inline] , at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz.1.132/4826: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4828: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4834: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4838: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4843: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4844: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4865: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4868: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4871: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4872: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4874: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4897: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4899: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4907: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4908: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 1 lock held by syz-executor/4911: #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffff800017730fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6ec/0xce4 net/core/rtnetlink.c:6147 2 locks held by dhcpcd/4932: #0: ffff0000d76e4410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #0: ffff0000d76e4410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline] #0: ffff0000d76e4410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x7c/0x1f8 net/socket.c:1400 #1: ffff80001529cbb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffff80001529cbb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a8/0x6f0 kernel/rcu/tree_exp.h:962 =============================================