INFO: task kworker/1:0:17 blocked for more than 143 seconds.
      Not tainted 5.9.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:0     state:D stack:26072 pid:   17 ppid:     2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0xec9/0x2280 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661
 __mutex_lock_common kernel/locking/mutex.c:1033 [inline]
 __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103
 addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4568
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Showing all locks held in the system:
3 locks held by kworker/0:0/5:
 #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240
 #1: ffffc90000cbfda8 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244
 #2: ffffffff8b14d828 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
3 locks held by kworker/1:0/17:
 #0: ffff888099b2b938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888099b2b938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff888099b2b938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff888099b2b938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff888099b2b938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff888099b2b938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240
 #1: ffffc90000d8fda8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244
 #2: ffffffff8b14d828 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4568
1 lock held by khungtaskd/1176:
 #0: ffffffff8a067f00 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5852
1 lock held by systemd-journal/3916:
1 lock held by in:imklog/6550:
 #0: ffff88809533caf0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930
1 lock held by syz-executor.2/8614:

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

NMI backtrace for cpu 0
CPU: 0 PID: 1176 Comm: khungtaskd Not tainted 5.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x198/0x1fd lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0xd7d/0x1000 kernel/hung_task.c:295
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3916 Comm: systemd-journal Not tainted 5.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:get_bucket lib/debugobjects.c:472 [inline]
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:951 [inline]
RIP: 0010:debug_check_no_obj_freed+0x7b/0x41c lib/debugobjects.c:998
Code: 00 00 00 00 49 bf 00 00 00 00 00 fc ff df 49 be 00 01 00 00 00 00 ad de 48 01 f0 48 89 44 24 40 48 ba eb 83 b5 80 46 86 c8 61 <48> 8b 44 24 18 48 c1 e8 0c 48 0f af c2 48 c1 e8 32 48 8d 04 c0 48
RSP: 0018:ffffc90001fafb80 EFLAGS: 00000087
RAX: ffff888042c33000 RBX: ffff888042c32000 RCX: 0000000000000000
RDX: 61c8864680b583eb RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffff888042c32000 R08: 0000000000000000 R09: ffffffff8d665ce3
R10: fffffbfff1accb9c R11: 0000000000000000 R12: 1ffffffff1accb9b
R13: 0000000000000000 R14: dead000000000100 R15: dffffc0000000000
FS:  00007f376774b8c0(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3764b23028 CR3: 000000009372b000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 free_pages_prepare mm/page_alloc.c:1214 [inline]
 __free_pages_ok+0x240/0xd00 mm/page_alloc.c:1471
 slab_destroy mm/slab.c:1625 [inline]
 slabs_destroy+0x89/0xc0 mm/slab.c:1641
 cache_flusharray mm/slab.c:3405 [inline]
 ___cache_free+0x506/0x750 mm/slab.c:3455
 qlink_free mm/kasan/quarantine.c:149 [inline]
 qlist_free_all+0x98/0x170 mm/kasan/quarantine.c:168
 quarantine_reduce+0x17e/0x200 mm/kasan/quarantine.c:261
 __kasan_kmalloc.constprop.0+0x9e/0xd0 mm/kasan/common.c:442
 slab_post_alloc_hook mm/slab.h:518 [inline]
 slab_alloc mm/slab.c:3312 [inline]
 __do_kmalloc mm/slab.c:3653 [inline]
 __kmalloc+0x178/0x360 mm/slab.c:3664
 kmalloc include/linux/slab.h:559 [inline]
 kzalloc include/linux/slab.h:666 [inline]
 lsm_cred_alloc security/security.c:532 [inline]
 security_prepare_creds+0x10e/0x190 security/security.c:1631
 prepare_creds+0x4bd/0x6c0 kernel/cred.c:285
 access_override_creds fs/open.c:353 [inline]
 do_faccessat+0x3d7/0x820 fs/open.c:417
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f3766a079c7
Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48
RSP: 002b:00007fffdfd27648 EFLAGS: 00000246 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 00007fffdfd2a670 RCX: 00007f3766a079c7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055ce512159a3
RBP: 00007fffdfd27790 R08: 000055ce5120b3e5 R09: 0000000000000018
R10: 0000000000000030 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 000055ce516958a0 R15: 00007fffdfd27c80