INFO: task kworker/u8:3:5841 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:3    state:D stack:23112 pid:5841  tgid:5841  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 addrconf_verify_work+0x19/0x30
 process_scheduled_works+0xb6e/0x18c0
 worker_thread+0xa53/0xfc0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
INFO: task syz.8.7864:530 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.7864      state:D stack:26112 pid:530   tgid:529   ppid:28235  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 rtnl_dumpit+0x92/0x200
 netlink_dump+0x722/0xe80
 __netlink_dump_start+0x5cb/0x7e0
 rtnetlink_rcv_msg+0xa3a/0xbe0
 netlink_rcv_skb+0x232/0x4b0
 netlink_unicast+0x80f/0x9b0
 netlink_sendmsg+0x813/0xb40
 ____sys_sendmsg+0x972/0x9f0
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1bd/0x2a0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f736f59c799
RSP: 002b:00007f7370466028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f736f815fa0 RCX: 00007f736f59c799
RDX: 0000000000004080 RSI: 0000200000000000 RDI: 0000000000000005
RBP: 00007f736f632c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f736f816038 R14: 00007f736f815fa0 R15: 00007ffc1e524708
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
1 lock held by dhcpcd/5556:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x65f/0xe30
2 locks held by getty/5637:
 #0: ffff88816ade60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
3 locks held by kworker/u8:3/5841:
 #0: ffff888112731148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0
 #1: ffffc9000669fc40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0
 #2: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30
2 locks held by syz.0.7860/508:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
 #1: ffffffff8e764878 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
5 locks held by syz.1.7861/512:
2 locks held by syz.8.7864/530:
 #0: ffff88819b0c26f0 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0
 #1: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200
1 lock held by syz-executor/535:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0
1 lock held by syz-executor/540:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0
1 lock held by syz-executor/544:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0
1 lock held by syz-executor/554:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0
1 lock held by syz-executor/557:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0
1 lock held by syz-executor/563:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0
1 lock held by syz-executor/571:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0
1 lock held by syz-executor/575:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0
1 lock held by syz-executor/578:
 #0: ffffffff8fbceb48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 35 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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 512 Comm: syz.1.7861 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
RIP: 0010:__lock_acquire+0x21/0x2cf0
Code: 90 90 90 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 48 81 ec e8 00 00 00 65 48 8b 05 37 d1 7a 11 48 89 84 24 e0 00 00 00 <65> 48 8b 05 0f d1 7a 11 48 89 44 24 08 31 ed 83 3d b9 58 70 0e 00
RSP: 0018:ffffc90000a08438 EFLAGS: 00000092
RAX: 965e29a2ae0bb800 RBX: 0000000000000246 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e75e5e0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90000a08718 R11: ffffffff81b0c390 R12: 0000000000000002
R13: ffffffff8e75e5e0 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f8c1be3a6c0(0000) GS:ffff8882a945a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffec46e1e78 CR3: 0000000116848000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0xf0/0x2e0
 unwind_next_frame+0xc2/0x23c0
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_node_noprof+0x384/0x690
 __alloc_skb+0x27d/0x7d0
 new_skb+0x2f/0x2b0
 aoecmd_cfg+0x2b1/0x800
 call_timer_fn+0x192/0x640
 __run_timer_base+0x652/0x8b0
 run_timer_softirq+0xb7/0x170
 handle_softirqs+0x22a/0x870
 __irq_exit_rcu+0x5f/0x150
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80
Code: f7 e8 1d c1 f0 f5 f7 c3 00 02 00 00 74 05 e8 d0 1a 1c f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> e4 7d e2 f5 65 8b 05 0d f0 6a 07 85 c0 74 18 5b 41 5e c3 cc cc
RSP: 0018:ffffc900071e7348 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000286 RCX: 0000000000000001
RDX: 0000000000000007 RSI: ffffffff8def8e53 RDI: 0000000000000001
RBP: 0000000000000003 R08: ffffffff9011b4b7 R09: 1ffffffff2023696
R10: dffffc0000000000 R11: fffffbfff2023697 R12: 1ffff11004857440
R13: 0000000000000003 R14: ffffffff8e764940 R15: dffffc0000000000
 __rcu_read_unlock+0x83/0xe0
 __reset_page_owner+0x85/0x1f0
 __free_frozen_pages+0xc2b/0xdb0
 __slab_free+0x263/0x2b0
 qlist_free_all+0x97/0x100
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_lru_noprof+0x2b8/0x640
 proc_alloc_inode+0x2a/0xc0
 alloc_inode+0x6a/0x1b0
 new_inode+0x22/0x170
 proc_pid_make_inode+0x21/0x130
 proc_pident_instantiate+0x6d/0x2b0
 proc_pident_lookup+0x1b7/0x270
 __lookup_slow+0x2b7/0x410
 lookup_slow+0x53/0x70
 link_path_walk+0xd1e/0x18d0
 path_openat+0x2c3/0x3860
 do_file_open+0x23e/0x4a0
 do_sys_openat2+0x113/0x200
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8c1af5cfce
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007f8c1be39ec8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f8c1be3a6c0 RCX: 00007f8c1af5cfce
RDX: 0000000000000002 RSI: 00007f8c1be39f90 RDI: ffffffffffffff9c
RBP: 00007f8c1b032c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8c1b216038 R14: 00007f8c1b215fa0 R15: 00007ffe1df24038
 </TASK>
