INFO: task dhcpcd:5554 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:21672 pid:5554  tgid:5554  ppid:5553   task_flags:0x400140 flags:0x00080001
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 rtnl_dumpit+0x92/0x200
 netlink_dump+0x6e4/0xe90
 netlink_recvmsg+0x676/0xa30
 sock_recvmsg+0x22c/0x270
 ____sys_recvmsg+0x1c9/0x460
 ___sys_recvmsg+0x1b5/0x510
 __x64_sys_recvmsg+0x198/0x260
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7b95c3c91e
RSP: 002b:00007ffec9001868 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007ffec9002990 RCX: 00007f7b95c3c91e
RDX: 0000000000000000 RSI: 00007ffec90028b0 RDI: 0000000000000005
RBP: 00007ffec9002920 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000000ef R11: 0000000000000246 R12: 0000000000000de8
R13: 00007ffec9002894 R14: 00007ffec90028b0 R15: 00007ffec90028a0
 </TASK>
INFO: task syz-executor:12306 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:23848 pid:12306 tgid:12306 ppid:1      task_flags:0x400140 flags:0x00080003
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 ip_tunnel_init_net+0x2ab/0x800
 ops_init+0x35c/0x5c0
 setup_net+0xfe/0x320
 copy_net_ns+0x34e/0x4e0
 create_new_namespaces+0x3f3/0x720
 unshare_nsproxy_namespaces+0x11c/0x170
 ksys_unshare+0x4c8/0x8c0
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2536b90ec7
RSP: 002b:00007ffecff58208 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f2536de5f40 RCX: 00007f2536b90ec7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f2536de67b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffecff584d8 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:12309 blocked for more than 147 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:23720 pid:12309 tgid:12309 ppid:1      task_flags:0x400140 flags:0x00080003
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 add_one_compat_dev+0xee/0x5c0
 rdma_dev_init_net+0x1dd/0x270
 ops_init+0x35c/0x5c0
 setup_net+0xfe/0x320
 copy_net_ns+0x34e/0x4e0
 create_new_namespaces+0x3f3/0x720
 unshare_nsproxy_namespaces+0x11c/0x170
 ksys_unshare+0x4c8/0x8c0
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff443f90ec7
RSP: 002b:00007ffe4bbf7828 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007ff4441e5f40 RCX: 00007ff443f90ec7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007ff4441e67b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffe4bbf7af8 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:12312 blocked for more than 149 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:23848 pid:12312 tgid:12312 ppid:1      task_flags:0x400140 flags:0x00080003
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 ib_get_eth_speed+0x151/0x7b0
 rxe_query_port+0x93/0x3b0
 ib_query_port+0x170/0x830
 ib_setup_port_attrs+0x24e/0x2070
 add_one_compat_dev+0x3d6/0x5c0
 rdma_dev_init_net+0x1dd/0x270
 ops_init+0x35c/0x5c0
 setup_net+0xfe/0x320
 copy_net_ns+0x34e/0x4e0
 create_new_namespaces+0x3f3/0x720
 unshare_nsproxy_namespaces+0x11c/0x170
 ksys_unshare+0x4c8/0x8c0
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd701590ec7
RSP: 002b:00007ffdfcf3a6f8 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fd7017e5f40 RCX: 00007fd701590ec7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007fd7017e67b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffdfcf3a9c8 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
6 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/34:
 #0: ffffffff8df3d6a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by dhcpcd/5554:
 #0: ffff8881b2c4e6f0 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xbd/0xe90
 #1: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200
2 locks held by getty/5635:
 #0: ffff88817365c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
5 locks held by kworker/u8:2/5822:
 #0: ffff888100ef7948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900044d7ba0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f2bf1b0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820
 #3: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x990
 #4: ffffffff8df43138 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
3 locks held by kworker/u8:3/5833:
 #0: ffff888170e09148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90004567ba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30
1 lock held by udevd/7208:
 #0: ffff88816b77e358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
3 locks held by kworker/1:9/10859:
 #0: ffff888100076948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90003e87ba0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0xa1/0xf40
1 lock held by syz.0.1620/12276:
 #0: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
2 locks held by syz-executor/12306:
 #0: ffffffff8f2bf1b0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0
 #1: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2ab/0x800
4 locks held by syz-executor/12309:
 #0: ffffffff8f2bf1b0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0
 #1: ffffffff8f038030 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x19a/0x270
 #2: ffffffff8f0381f0 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x1d2/0x270
 #3: ffff88816c9c0f98 (&device->compat_devs_mutex){+.+.}-{4:4}, at: add_one_compat_dev+0xee/0x5c0
6 locks held by syz-executor/12312:
 #0: ffffffff8f2bf1b0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0
 #1: ffffffff8f038030 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x19a/0x270
 #2: ffffffff8f0381f0 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x1d2/0x270
 #3: ffff88816c9c0f98 (&device->compat_devs_mutex){+.+.}-{4:4}, at: add_one_compat_dev+0xee/0x5c0
 #4: ffff88816c9c1290 (&rxe->usdev_lock){+.+.}-{4:4}, at: rxe_query_port+0x7e/0x3b0
 #5: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: ib_get_eth_speed+0x151/0x7b0
1 lock held by syz-executor/12317:
 #0: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0
1 lock held by syz-executor/12319:
 #0: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0
1 lock held by syz-executor/12322:
 #0: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0
1 lock held by syz-executor/12327:
 #0: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0
1 lock held by syz-executor/12329:
 #0: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0
1 lock held by syz-executor/12331:
 #0: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0
1 lock held by syz-executor/12337:
 #0: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0
1 lock held by syz-executor/12340:
 #0: ffffffff8f2cc148 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf60/0xfa0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5822 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:unwind_next_frame+0x351/0x2390
Code: 48 11 00 00 48 c7 c0 d0 86 8a 8f 49 29 c5 48 c7 c6 1c fc 01 90 49 c1 fd 02 4a 8d 14 6d 00 00 00 00 4c 01 ea 48 01 d2 48 01 f2 <48> bd 00 00 00 00 00 fc ff df 0f 84 37 01 00 00 4c 8d 62 04 4c 8d
RSP: 0018:ffffc90000006bf8 EFLAGS: 00000282
RAX: ffffffff8ff047d0 RBX: ffffffff8ff047d4 RCX: ffffffff8ff047d8
RDX: ffffffff909a9da2 RSI: ffffffff909a9da2 RDI: ffffffff8bbf0700
RBP: ffffffff8ff047d8 R08: 0000000000000009 R09: ffffffff81738c45
R10: ffffc90000006d18 R11: ffffffff81ac2ea0 R12: ffffffff89f5cc19
R13: 0000000000000000 R14: ffffc90000006cc8 R15: ffffffff8ff047d4
FS:  0000000000000000(0000) GS:ffff88818eb38000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ec37f9d508 CR3: 00000001708b0000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_node_noprof+0x433/0x710
 kmalloc_reserve+0xbd/0x290
 __alloc_skb+0x142/0x2d0
 synproxy_send_client_synack_ipv6+0x169/0xca0
 nft_synproxy_eval_v6+0x36e/0x560
 nft_synproxy_do_eval+0x3d7/0x570
 nft_do_chain+0x40c/0x1920
 nft_do_chain_inet+0x25d/0x340
 nf_hook_slow+0xc5/0x220
 NF_HOOK+0x206/0x3a0
 ip6_input+0x16a/0x270
 NF_HOOK+0x30c/0x3a0
 __netif_receive_skb+0xd3/0x380
 process_backlog+0x622/0x1530
 __napi_poll+0xae/0x320
 net_rx_action+0x672/0xe50
 handle_softirqs+0x286/0x870
 do_softirq+0xec/0x180
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x17d/0x1c0
 addrconf_ifdown+0x694/0x1880
 addrconf_notify+0x1bc/0x1010
 notifier_call_chain+0x1b6/0x3e0
 unregister_netdevice_many_notify+0x1860/0x2390
 ops_undo_list+0x3dc/0x990
 cleanup_net+0x4d8/0x820
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
