======================================
| [   25.785121][  T303] ==================================================================
| [   25.785465][  T303] BUG: KASAN: null-ptr-deref in try_to_grab_pending (./arch/x86/include/asm/bitops.h:136 ./include/asm-generic/bitops/instrumented-atomic.h:72 kernel/workqueue.c:2072)
| [   25.785770][  T303] Write of size 8 at addr 0000000000000000 by task ip/303
| [   25.786032][  T303]
[   25.786151][  T303] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   25.786153][  T303] Call Trace:
[   25.786155][  T303]  <TASK>
[   25.786157][  T303]  dump_stack_lvl (lib/dump_stack.c:123)
[   25.786165][  T303]  ? try_to_grab_pending (./arch/x86/include/asm/bitops.h:136 ./include/asm-generic/bitops/instrumented-atomic.h:72 kernel/workqueue.c:2072)
[   25.786169][  T303]  kasan_report (mm/kasan/report.c:597)
[   25.786176][  T303]  ? try_to_grab_pending (./arch/x86/include/asm/bitops.h:136 ./include/asm-generic/bitops/instrumented-atomic.h:72 kernel/workqueue.c:2072)
[   25.786182][  T303]  kasan_check_range (mm/kasan/generic.c:194 mm/kasan/generic.c:200)
[   25.786186][  T303]  try_to_grab_pending (./arch/x86/include/asm/bitops.h:136 ./include/asm-generic/bitops/instrumented-atomic.h:72 kernel/workqueue.c:2072)
[   25.786190][  T303]  __cancel_work (kernel/workqueue.c:2161 kernel/workqueue.c:4364)
[   25.786194][  T303]  ? enable_delayed_work (kernel/workqueue.c:4359)
[   25.786199][  T303]  ? qdisc_destroy (net/sched/sch_generic.c:1355)
[   25.786205][  T303]  __cancel_work_sync (kernel/workqueue.c:4383)
[   25.786209][  T303]  __dev_close_many (net/core/dev.c:1879 (discriminator 2) net/core/dev.c:1932 (discriminator 2))
[   25.786215][  T303]  ? netdev_notify_peers (net/core/dev.c:1891)
[   25.786218][  T303]  ? netif_close_many (net/core/dev.c:1959)
[   25.786223][  T303]  netif_close_many (net/core/dev.c:1959)
[   25.786226][  T303]  ? __mutex_handoff (kernel/locking/mutex.c:88)
[   25.786231][  T303]  ? __dev_close_many (net/core/dev.c:1949)
[   25.786235][  T303]  ? netif_close_many_and_unlock (net/core/dev.c:12476)
[   25.786239][  T303]  unregister_netdevice_many_notify (net/core/dev.c:12545)
[   25.786243][  T303]  ? rtnl_dellink (net/core/rtnetlink.c:3564)
[   25.786249][  T303]  ? dev_ingress_queue_create (net/core/dev.c:12499)
[   25.786253][  T303]  ? rtnl_is_locked (net/core/rtnetlink.c:169)
[   25.786255][  T303]  ? unregister_netdevice_queue (net/core/dev.c:12442)
[   25.786259][  T303]  ? unregister_netdevice_many (net/core/dev.c:12441)
[   25.786262][  T303]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   25.786265][  T303]  ? __nla_validate_parse (./include/net/netlink.h:1307 (discriminator 1) lib/nlattr.c:622 (discriminator 1))
[   25.786273][  T303]  rtnl_dellink (net/core/rtnetlink.c:3530 net/core/rtnetlink.c:3570)
[   25.786277][  T303]  ? valid_bridge_getlink_req.constprop.0 (net/core/rtnetlink.c:3536)
[   25.786297][  T303]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   25.786303][  T303]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   25.786312][  T303]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   25.786318][  T303]  ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 net/core/rtnetlink.c:6956)
[   25.786322][  T303]  ? __lock_release (kernel/locking/lockdep.c:5536)
[   25.786327][  T303]  ? valid_bridge_getlink_req.constprop.0 (net/core/rtnetlink.c:3536)
[   25.786330][  T303]  rtnetlink_rcv_msg (net/core/rtnetlink.c:6958)
[   25.786334][  T303]  ? rtnl_port_fill (net/core/rtnetlink.c:6861)
[   25.786338][  T303]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   25.786344][  T303]  netlink_rcv_skb (net/netlink/af_netlink.c:2550)
[   25.786348][  T303]  ? rtnl_port_fill (net/core/rtnetlink.c:6861)
[   25.786352][  T303]  ? netlink_ack (net/netlink/af_netlink.c:2527)
[   25.786358][  T303]  ? netlink_deliver_tap (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 net/netlink/af_netlink.c:340)
[   25.786361][  T303]  ? netlink_deliver_tap (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 ./include/net/netns/generic.h:48 net/netlink/af_netlink.c:333)
[   25.786365][  T303]  netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
[   25.786369][  T303]  ? netlink_attachskb (net/netlink/af_netlink.c:1329)
[   25.786372][  T303]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   25.786377][  T303]  netlink_sendmsg (net/netlink/af_netlink.c:1894)
[   25.786381][  T303]  ? netlink_unicast (net/netlink/af_netlink.c:1813)
[   25.786384][  T303]  ? __import_iovec (lib/iov_iter.c:1346 lib/iov_iter.c:1361)
[   25.786389][  T303]  ? netlink_unicast (net/netlink/af_netlink.c:1813)
[   25.786392][  T303]  ____sys_sendmsg (net/socket.c:727 net/socket.c:742 net/socket.c:2630)
[   25.786396][  T303]  ? get_timestamp.constprop.0 (net/socket.c:2576)
[   25.786398][  T303]  ? __copy_msghdr (net/socket.c:2556)
[   25.786406][  T303]  ___sys_sendmsg (net/socket.c:2686)
[   25.786409][  T303]  ? kasan_record_aux_stack (mm/kasan/generic.c:559)
[   25.786412][  T303]  ? __call_rcu_common.constprop.0 (./arch/x86/include/asm/irqflags.h:26 ./arch/x86/include/asm/irqflags.h:109 ./arch/x86/include/asm/irqflags.h:127 kernel/rcu/tree.c:3125)
[   25.786416][  T303]  ? copy_msghdr_from_user (net/socket.c:2673)
[   25.786421][  T303]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   25.786426][  T303]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   25.786431][  T303]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   25.786435][  T303]  ? __virt_addr_valid (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:979 ./include/linux/mmzone.h:2197 arch/x86/mm/physaddr.c:65)
[   25.786443][  T303]  ? __lock_release (kernel/locking/lockdep.c:5536)
[   25.786451][  T303]  __sys_sendmsg (net/socket.c:2716)
[   25.786455][  T303]  ? __call_rcu_common.constprop.0 (kernel/rcu/tree.c:3148)
[   25.786458][  T303]  ? __sys_sendmsg_sock (net/socket.c:2701)
[   25.786465][  T303]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[   25.786470][  T303]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[   25.786476][  T303]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   25.786479][  T303] RIP: 0033:0x7fd0b16531d7
[   25.786483][  T303] Code: 0e 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
All code
========
   0:	0e                   	(bad)
   1:	00 f7                	add    %dh,%bh
   3:	d8 64 89 02          	fsubs  0x2(%rcx,%rcx,4)
   7:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   e:	eb b9                	jmp    0xffffffffffffffc9
  10:	0f 1f 00             	nopl   (%rax)
  13:	f3 0f 1e fa          	endbr64
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 10                	jne    0x33
  23:	b8 2e 00 00 00       	mov    $0x2e,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 51                	ja     0x83
  32:	c3                   	ret
  33:	48 83 ec 28          	sub    $0x28,%rsp
  37:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  3b:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 51                	ja     0x59
   8:	c3                   	ret
   9:	48 83 ec 28          	sub    $0x28,%rsp
   d:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  11:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)
[   25.786486][  T303] RSP: 002b:00007ffc59856198 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[   25.786490][  T303] RAX: ffffffffffffffda RBX: 00007ffc598568c0 RCX: 00007fd0b16531d7
[   25.786492][  T303] RDX: 0000000000000000 RSI: 00007ffc59856200 RDI: 0000000000000005
[   25.786494][  T303] RBP: 0000000000000002 R08: 0000000000000003 R09: 0000000000000078
[   25.786495][  T303] R10: 00007fd0b154ff60 R11: 0000000000000246 R12: 0000000000000002
[   25.786497][  T303] R13: 00000000691cd7a8 R14: 0000000000499600 R15: 0000000000000000
| [   25.803984][  T303] #PF: error_code(0x0002) - not-present page
| [   25.804209][  T303] PGD 4ec9067 P4D 4ec9067 PUD bfcf067 PMD 0
| [   25.804434][  T303] Oops: Oops: 0002 [#1] SMP KASAN
| [   25.804989][  T303] Tainted: [B]=BAD_PAGE
[   25.805135][  T303] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   25.805355][  T303] RIP: 0010:try_to_grab_pending (./arch/x86/include/asm/bitops.h:136 ./include/asm-generic/bitops/instrumented-atomic.h:72 kernel/workqueue.c:2072)
[   25.805582][  T303] Code: 00 41 89 c0 b8 01 00 00 00 45 85 c0 74 0f 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 be 08 00 00 00 48 89 df e8 1f 93 82 00 <f0> 48 0f ba 2b 00 72 11 48 83 c4 10 31 c0 5b 5d 41 5c 41 5d 41 5e
All code
========
   0:	00 41 89             	add    %al,-0x77(%rcx)
   3:	c0 b8 01 00 00 00 45 	sarb   $0x45,0x1(%rax)
   a:	85 c0                	test   %eax,%eax
   c:	74 0f                	je     0x1d
   e:	48 83 c4 10          	add    $0x10,%rsp
  12:	5b                   	pop    %rbx
  13:	5d                   	pop    %rbp
  14:	41 5c                	pop    %r12
  16:	41 5d                	pop    %r13
  18:	41 5e                	pop    %r14
  1a:	41 5f                	pop    %r15
  1c:	c3                   	ret
  1d:	be 08 00 00 00       	mov    $0x8,%esi
  22:	48 89 df             	mov    %rbx,%rdi
  25:	e8 1f 93 82 00       	call   0x829349
  2a:*	f0 48 0f ba 2b 00    	lock btsq $0x0,(%rbx)		<-- trapping instruction
  30:	72 11                	jb     0x43
  32:	48 83 c4 10          	add    $0x10,%rsp
  36:	31 c0                	xor    %eax,%eax
  38:	5b                   	pop    %rbx
  39:	5d                   	pop    %rbp
  3a:	41 5c                	pop    %r12
  3c:	41 5d                	pop    %r13
  3e:	41 5e                	pop    %r14

Code starting with the faulting instruction
===========================================
   0:	f0 48 0f ba 2b 00    	lock btsq $0x0,(%rbx)
   6:	72 11                	jb     0x19
   8:	48 83 c4 10          	add    $0x10,%rsp
   c:	31 c0                	xor    %eax,%eax
   e:	5b                   	pop    %rbx
   f:	5d                   	pop    %rbp
  10:	41 5c                	pop    %r12
  12:	41 5d                	pop    %r13
  14:	41 5e                	pop    %r14
[   25.806227][  T303] RSP: 0018:ffffc90000606f08 EFLAGS: 00010046
[   25.806455][  T303] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffffac049b8a
[   25.806713][  T303] RDX: fffffbfff61acacd RSI: 0000000000000008 RDI: ffffffffb0d65660
[   25.806993][  T303] RBP: ffffc90000606f70 R08: 0000000000000001 R09: fffffbfff61acacc
[   25.807260][  T303] R10: ffffffffb0d65667 R11: ffffc900006069c0 R12: 0000000000000000
[   25.807533][  T303] R13: 0000000000000282 R14: ffff888002aac000 R15: dffffc0000000000
[   25.807790][  T303] FS:  00007fd0b1485800(0000) GS:ffff8880bc387000(0000) knlGS:0000000000000000
[   25.808122][  T303] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   25.808343][  T303] CR2: 0000000000000000 CR3: 000000000d9ba002 CR4: 0000000000772ef0
[   25.808607][  T303] PKRU: 55555554
[   25.808743][  T303] Call Trace:
[   25.808885][  T303]  <TASK>
[   25.808977][  T303]  __cancel_work (kernel/workqueue.c:2161 kernel/workqueue.c:4364)
[   25.809163][  T303]  ? enable_delayed_work (kernel/workqueue.c:4359)
[   25.809339][  T303]  ? qdisc_destroy (net/sched/sch_generic.c:1355)
[   25.809521][  T303]  __cancel_work_sync (kernel/workqueue.c:4383)
[   25.809701][  T303]  __dev_close_many (net/core/dev.c:1879 (discriminator 2) net/core/dev.c:1932 (discriminator 2))
[   25.809925][  T303]  ? netdev_notify_peers (net/core/dev.c:1891)
[   25.810112][  T303]  ? netif_close_many (net/core/dev.c:1959)
[   25.810279][  T303]  netif_close_many (net/core/dev.c:1959)
[   25.810457][  T303]  ? __mutex_handoff (kernel/locking/mutex.c:88)
[   25.810626][  T303]  ? __dev_close_many (net/core/dev.c:1949)
[   25.810807][  T303]  ? netif_close_many_and_unlock (net/core/dev.c:12476)
[   25.811029][  T303]  unregister_netdevice_many_notify (net/core/dev.c:12545)
[   25.811245][  T303]  ? rtnl_dellink (net/core/rtnetlink.c:3564)
[   25.811428][  T303]  ? dev_ingress_queue_create (net/core/dev.c:12499)
[   25.811604][  T303]  ? rtnl_is_locked (net/core/rtnetlink.c:169)
[   25.811794][  T303]  ? unregister_netdevice_queue (net/core/dev.c:12442)
[   25.812010][  T303]  ? unregister_netdevice_many (net/core/dev.c:12441)
[   25.812193][  T303]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   25.812367][  T303]  ? __nla_validate_parse (./include/net/netlink.h:1307 (discriminator 1) lib/nlattr.c:622 (discriminator 1))
[   25.812545][  T303]  rtnl_dellink (net/core/rtnetlink.c:3530 net/core/rtnetlink.c:3570)
[   25.812779][  T303]  ? valid_bridge_getlink_req.constprop.0 (net/core/rtnetlink.c:3536)
[   25.813029][  T303]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   25.813207][  T303]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   25.813384][  T303]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   25.813561][  T303]  ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 net/core/rtnetlink.c:6956)
[   25.813737][  T303]  ? __lock_release (kernel/locking/lockdep.c:5536)
[   25.813934][  T303]  ? valid_bridge_getlink_req.constprop.0 (net/core/rtnetlink.c:3536)
[   25.814182][  T303]  rtnetlink_rcv_msg (net/core/rtnetlink.c:6958)
[   25.814358][  T303]  ? rtnl_port_fill (net/core/rtnetlink.c:6861)
[   25.814534][  T303]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   25.814712][  T303]  netlink_rcv_skb (net/netlink/af_netlink.c:2550)
[   25.814903][  T303]  ? rtnl_port_fill (net/core/rtnetlink.c:6861)
[   25.815080][  T303]  ? netlink_ack (net/netlink/af_netlink.c:2527)
[   25.815253][  T303]  ? netlink_deliver_tap (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 net/netlink/af_netlink.c:340)
[   25.815434][  T303]  ? netlink_deliver_tap (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 ./include/net/netns/generic.h:48 net/netlink/af_netlink.c:333)
[   25.815610][  T303]  netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
[   25.815799][  T303]  ? netlink_attachskb (net/netlink/af_netlink.c:1329)
[   25.815982][  T303]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   25.816162][  T303]  netlink_sendmsg (net/netlink/af_netlink.c:1894)
[   25.816333][  T303]  ? netlink_unicast (net/netlink/af_netlink.c:1813)
[   25.816507][  T303]  ? __import_iovec (lib/iov_iter.c:1346 lib/iov_iter.c:1361)
[   25.816681][  T303]  ? netlink_unicast (net/netlink/af_netlink.c:1813)
[   25.816879][  T303]  ____sys_sendmsg (net/socket.c:727 net/socket.c:742 net/socket.c:2630)
[   25.817067][  T303]  ? get_timestamp.constprop.0 (net/socket.c:2576)
[   25.817275][  T303]  ? __copy_msghdr (net/socket.c:2556)
[   25.817459][  T303]  ___sys_sendmsg (net/socket.c:2686)
[   25.817627][  T303]  ? kasan_record_aux_stack (mm/kasan/generic.c:559)
[   25.817819][  T303]  ? __call_rcu_common.constprop.0 (./arch/x86/include/asm/irqflags.h:26 ./arch/x86/include/asm/irqflags.h:109 ./arch/x86/include/asm/irqflags.h:127 kernel/rcu/tree.c:3125)
[   25.818057][  T303]  ? copy_msghdr_from_user (net/socket.c:2673)
[   25.818242][  T303]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   25.818419][  T303]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   25.818599][  T303]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   25.818787][  T303]  ? __virt_addr_valid (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:979 ./include/linux/mmzone.h:2197 arch/x86/mm/physaddr.c:65)
[   25.818973][  T303]  ? __lock_release (kernel/locking/lockdep.c:5536)
[   25.819159][  T303]  __sys_sendmsg (net/socket.c:2716)
[   25.819333][  T303]  ? __call_rcu_common.constprop.0 (kernel/rcu/tree.c:3148)
[   25.819548][  T303]  ? __sys_sendmsg_sock (net/socket.c:2701)
[   25.819859][  T303]  ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:751)
[   25.820045][  T303]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[   25.820225][  T303]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   25.820450][  T303] RIP: 0033:0x7fd0b16531d7
[   25.820788][  T303] Code: 0e 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
All code
========
   0:	0e                   	(bad)
   1:	00 f7                	add    %dh,%bh
   3:	d8 64 89 02          	fsubs  0x2(%rcx,%rcx,4)
   7:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   e:	eb b9                	jmp    0xffffffffffffffc9
  10:	0f 1f 00             	nopl   (%rax)
  13:	f3 0f 1e fa          	endbr64
  17:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  1e:	00 
  1f:	85 c0                	test   %eax,%eax
  21:	75 10                	jne    0x33
  23:	b8 2e 00 00 00       	mov    $0x2e,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 51                	ja     0x83
  32:	c3                   	ret
  33:	48 83 ec 28          	sub    $0x28,%rsp
  37:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  3b:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 51                	ja     0x59
   8:	c3                   	ret
   9:	48 83 ec 28          	sub    $0x28,%rsp
   d:	89 54 24 1c          	mov    %edx,0x1c(%rsp)
  11:	48 89 74 24 10       	mov    %rsi,0x10(%rsp)
[   25.821546][  T303] RSP: 002b:00007ffc59856198 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[   25.821848][  T303] RAX: ffffffffffffffda RBX: 00007ffc598568c0 RCX: 00007fd0b16531d7
[   25.822132][  T303] RDX: 0000000000000000 RSI: 00007ffc59856200 RDI: 0000000000000005
[   25.822501][  T303] RBP: 0000000000000002 R08: 0000000000000003 R09: 0000000000000078
[   25.822776][  T303] R10: 00007fd0b154ff60 R11: 0000000000000246 R12: 0000000000000002


Finger prints:
kasan_report:kasan_check_range:try_to_grab_pending:__cancel_work:__cancel_work_sync
try_to_grab_pending:__cancel_work:__cancel_work_sync:__dev_close_many:netif_close_many