INFO: task syz.0.549:9014 blocked for more than 153 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.549       state:D stack:28120 pid:9014  tgid:9011  ppid:5847   task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 register_netdevice_notifier_net+0x1a/0xa0
 ops_init+0x35c/0x5c0
 setup_net+0x10c/0x320
 copy_net_ns+0x31b/0x4d0
 create_new_namespaces+0x3f3/0x720
 unshare_nsproxy_namespaces+0x11c/0x170
 ksys_unshare+0x4c8/0x8c0
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcd7db8ec29
RSP: 002b:00007fcd7eaa0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fcd7ddd6090 RCX: 00007fcd7db8ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000
RBP: 00007fcd7dc11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcd7ddd6128 R14: 00007fcd7ddd6090 R15: 00007ffe38bd94e8
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/u8:0/12:
1 lock held by khungtaskd/34:
 #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
1 lock held by kswapd0/90:
2 locks held by kswapd1/91:
1 lock held by syslogd/5278:
 #0: ffffffff8e846750 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_path_perm+0x1e3/0x4b0
4 locks held by udevd/5296:
 #0: ffffffff8e1f12b0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x131/0x4b0
 #1: ffff88810da06d60 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x12e/0x1ac0
 #2: ffff8881066a81e0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x217/0x1ac0
 #3: ffffffff8e23fb00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim+0xb8/0x300
2 locks held by dhcpcd/5591:
2 locks held by getty/5672:
 #0: ffff88802a50f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
3 locks held by kworker/u8:2/5716:
 #0: ffff8880218d8148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90002fafbc0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f53a248 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30
2 locks held by syz-executor/5834:
 #0: ffff888107597468 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x16a/0x1360
 #1: ffffffff8e23fb00 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim+0xb8/0x300
3 locks held by kworker/0:4/5884:
 #0: ffff88801a482148 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900038bfbc0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f53a248 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x95/0xf30
2 locks held by syz.1.548/9009:
2 locks held by syz.0.549/9014:
 #0: ffffffff8f52d3b0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0
 #1: ffffffff8f53a248 (rtnl_mutex){+.+.}-{4:4}, at: register_netdevice_notifier_net+0x1a/0xa0
2 locks held by syz-executor/9020:
4 locks held by syz-executor/9024:

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

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+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 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: 5877 Comm: kworker/u8:3 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: bat_events batadv_iv_send_outstanding_bat_ogm_packet
RIP: 0010:unwind_next_frame+0x9/0x2390
Code: 03 38 c1 7c 92 48 89 df e8 74 6c b0 00 eb 88 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 <41> 55 41 54 53 48 81 ec 98 00 00 00 49 89 fe 48 bd 00 00 00 00 00
RSP: 0018:ffffc90000007868 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc90000007940 RCX: c3d67db3d12da600
RDX: dffffc0000000000 RSI: ffffffff81ac3aac RDI: ffffc90000007888
RBP: ffffc90000007910 R08: ffffc90000007950 R09: 0000000000000000
R10: ffffc900000078d8 R11: ffffffff81ac3b00 R12: ffff888022fc0000
R13: 0000000000000000 R14: ffffffff81ac3b00 R15: ffffc90000007888
FS:  0000000000000000(0000) GS:ffff8880b863d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8e4c5d2060 CR3: 000000001fda6000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kmem_cache_free+0x18f/0x400
 rcu_core+0xcab/0x1770
 handle_softirqs+0x286/0x870
 do_softirq+0xec/0x180
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x17d/0x1c0
 batadv_iv_ogm_schedule+0x866/0xf00
 batadv_iv_send_outstanding_bat_ogm_packet+0x6c6/0x7e0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
