INFO: task syz.9.1755:20888 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.1755      state:D stack:24696 pid:20888 tgid:20887 ppid:20370  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6d9/0x940
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 user_get_super+0xc8/0x120
 __se_sys_quotactl+0x540/0x9e0
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4417f9cdd9
RSP: 002b:00007f4418ef6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f4418215fa0 RCX: 00007f4417f9cdd9
RDX: 0000000000000000 RSI: 0000200000000080 RDI: ffffffff80000901
RBP: 00007f4418032d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4418216038 R14: 00007f4418215fa0 R15: 00007ffdef5dc298
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/u8:0/12:
3 locks held by kworker/u9:1/32:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90000a87c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffffffff8fdd00c0 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
1 lock held by dhcpcd/5353:
 #0: ffffffff8fdd00c0 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0
2 locks held by getty/5441:
 #0: ffff8881713bb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
3 locks held by syz-executor/16415:
1 lock held by syz.9.1755/20888:
 #0: ffff88801d2180d8 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.5.1825/21670:
 #0: ffff88801d2180d8 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.4.1858/22245:
 #0: ffff88801d2180d8 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.4.1858/22277:
 #0: ffff88801d2180d8 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.9.1924/23027:
 #0: ffff88801d2180d8 (&type->s_umount_key#55){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
4 locks held by syz-executor/24698:
4 locks held by dhcpcd-run-hook/24766:

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

NMI backtrace for cpu 0
CPU: 0 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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd3/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 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: 24698 Comm: syz-executor 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+0x884/0x2cf0
Code: 01 d6 29 da 89 dd c1 c5 13 31 d5 01 f3 29 ee 01 eb c1 c5 04 31 f5 48 c1 e5 20 83 3d 29 2c 8f 0e 00 4d 89 e5 0f 85 1f 02 00 00 <48> 83 7c 24 28 00 0f 84 b3 01 00 00 41 8b 45 f8 25 ff 1f 00 00 48
RSP: 0018:ffffc90000a08570 EFLAGS: 00000046
RAX: 000000008b77321c RBX: 00000000e60071fc RCX: 0000000077854751
RDX: 000000000810ef47 RSI: 000000008e468aea RDI: ffff88802110bb00
RBP: a66124e200000000 R08: ffffffff8176f256 R09: ffffffff8e95cd60
R10: ffffc90000a08878 R11: ffffffff81b0ebd0 R12: ffff88802110c758
R13: ffff88802110c758 R14: ffff88802110bb00 R15: 0000000000000005
FS:  000055558ec88500(0000) GS:ffff8882a928d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f663d164ba8 CR3: 0000000024bec000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 lock_acquire+0x106/0x350
 unwind_next_frame+0xc3/0x2550
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 kasan_save_stack+0x3e/0x60
 kasan_record_aux_stack+0xbd/0xd0
 insert_work+0x3d/0x330
 __queue_work+0xccf/0xfc0
 call_timer_fn+0x192/0x5e0
 __run_timer_base+0x67e/0x8b0
 run_timer_softirq+0xb7/0x170
 handle_softirqs+0x22a/0x840
 __irq_exit_rcu+0xca/0x220
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:stack_trace_consume_entry+0xa2/0x280
Code: cc 41 0f b6 04 17 84 c0 0f 85 78 01 00 00 44 89 23 b0 01 e9 99 00 00 00 31 c0 e9 92 00 00 00 48 89 f8 48 c1 e8 03 80 3c 10 00 <74> 29 49 89 ff 48 89 74 24 08 49 89 d4 4c 89 04 24 4c 89 cb e8 e5
RSP: 0018:ffffc90004f4e778 EFLAGS: 00000246
RAX: 1ffff920009e9d10 RBX: ffffc90004f4e88c RCX: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff8230ce43 RDI: ffffc90004f4e880
RBP: 1ffff920009e9d12 R08: ffffc90004f4e890 R09: 0000000000000001
R10: ffffc90004f4e818 R11: ffffffff81b0ebd0 R12: 0000000000000000
R13: 1ffff920009e9d11 R14: ffffc90004f4e888 R15: 1ffff920009e9d11
 arch_stack_walk+0x10f/0x150
 stack_trace_save+0xa9/0x100
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kvmalloc_node_noprof+0x528/0x8a0
 veth_dev_init+0x368/0x570
 register_netdevice+0x6c6/0x1ec0
 veth_newlink+0x67b/0xb70
 rtnl_newlink_create+0x329/0xb70
 rtnl_newlink+0x166a/0x1bb0
 rtnetlink_rcv_msg+0x7d5/0xbe0
 netlink_rcv_skb+0x232/0x4b0
 netlink_unicast+0x75c/0x8e0
 netlink_sendmsg+0x813/0xb40
 __sys_sendto+0x672/0x710
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3db1f5d60e
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:00007fffad18fa68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055558ec88500 RCX: 00007f3db1f5d60e
RDX: 000000000000008c RSI: 00007f3db2d44670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fffad18fae4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f3db2d44670 R15: 0000000000000000
 </TASK>
