======================================
| [   15.279469][  T256] ==================================================================
| [   15.279780][  T256] BUG: KASAN: slab-use-after-free in kobject_put (lib/kobject.c:733)
| [   15.280060][  T256] Read of size 1 at addr ffff8880058826c4 by task tap/256
| [   15.280298][  T256]
[   15.280402][  T256] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   15.280405][  T256] Call Trace:
[   15.280407][  T256]  <TASK>
[   15.280409][  T256]  dump_stack_lvl (lib/dump_stack.c:123)
[   15.280416][  T256]  print_address_description.constprop.0 (mm/kasan/report.c:379)
[   15.280424][  T256]  ? kobject_put (lib/kobject.c:733)
[   15.280428][  T256]  print_report (mm/kasan/report.c:483)
[   15.280431][  T256]  ? kobject_put (lib/kobject.c:733)
[   15.280435][  T256]  ? kasan_addr_to_slab (./include/linux/mm.h:1245 mm/kasan/../slab.h:191 mm/kasan/common.c:47)
[   15.280439][  T256]  ? kobject_put (lib/kobject.c:733)
[   15.280442][  T256]  kasan_report (mm/kasan/report.c:597)
[   15.280446][  T256]  ? kobject_put (lib/kobject.c:733)
[   15.280451][  T256]  kobject_put (lib/kobject.c:733)
[   15.280455][  T256]  netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11670)
[   15.280462][  T256]  ? dev_ingress_queue_create (net/core/dev.c:12299)
[   15.280466][  T256]  ? generic_xdp_install (net/core/dev.c:11630)
[   15.280471][  T256]  ? __netdev_upper_dev_unlink (net/core/dev.c:8973)
[   15.280475][  T256]  rtnl_dellink (net/core/rtnetlink.c:3580)
[   15.280481][  T256]  ? valid_bridge_getlink_req.constprop.0 (net/core/rtnetlink.c:3536)
[   15.280501][  T256]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   15.280510][  T256]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   15.280516][  T256]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   15.280520][  T256]  ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 net/core/rtnetlink.c:6956)
[   15.280523][  T256]  ? __lock_release (kernel/locking/lockdep.c:5536)
[   15.280526][  T256]  ? valid_bridge_getlink_req.constprop.0 (net/core/rtnetlink.c:3536)
[   15.280530][  T256]  rtnetlink_rcv_msg (net/core/rtnetlink.c:6958)
[   15.280535][  T256]  ? rtnl_port_fill (net/core/rtnetlink.c:6861)
[   15.280538][  T256]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   15.280544][  T256]  netlink_rcv_skb (net/netlink/af_netlink.c:2550)
[   15.280549][  T256]  ? rtnl_port_fill (net/core/rtnetlink.c:6861)
[   15.280553][  T256]  ? netlink_ack (net/netlink/af_netlink.c:2527)
[   15.280559][  T256]  ? netlink_deliver_tap (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 net/netlink/af_netlink.c:340)
[   15.280562][  T256]  ? 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)
[   15.280565][  T256]  netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
[   15.280570][  T256]  ? netlink_attachskb (net/netlink/af_netlink.c:1329)
[   15.280572][  T256]  ? netlink_insert (net/netlink/af_netlink.c:591 (discriminator 3))
[   15.280576][  T256]  ? netlink_autobind.isra.0 (net/netlink/af_netlink.c:804)
[   15.280579][  T256]  ? netlink_autobind.isra.0 (net/netlink/af_netlink.c:827)
[   15.280583][  T256]  netlink_sendmsg (net/netlink/af_netlink.c:1894)
[   15.280587][  T256]  ? netlink_unicast (net/netlink/af_netlink.c:1813)
[   15.280589][  T256]  ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4472)
[   15.280596][  T256]  ? lockdep_init_map_type (kernel/locking/lockdep.c:4973)
[   15.280601][  T256]  __sys_sendto (net/socket.c:727 net/socket.c:742 net/socket.c:2244)
[   15.280606][  T256]  ? __ia32_sys_getpeername (net/socket.c:2211)
[   15.280611][  T256]  ? fd_install (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:979 fs/file.c:676)
[   15.280616][  T256]  ? __lock_release (kernel/locking/lockdep.c:5536)
[   15.280619][  T256]  ? fd_install (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:979 fs/file.c:676)
[   15.280623][  T256]  ? fd_install (./arch/x86/include/asm/preempt.h:104 ./include/linux/rcupdate.h:981 fs/file.c:676)
[   15.280627][  T256]  ? __sys_socket (net/socket.c:516 net/socket.c:1756)
[   15.280630][  T256]  ? update_socket_protocol+0x10/0x10
[   15.280632][  T256]  ? xfd_validate_state (arch/x86/kernel/fpu/xstate.c:1499 arch/x86/kernel/fpu/xstate.c:1543)
[   15.280640][  T256]  __x64_sys_sendto (net/socket.c:2247)
[   15.280642][  T256]  ? do_syscall_64 (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 ./include/linux/entry-common.h:124 arch/x86/entry/syscall_64.c:90)
[   15.280647][  T256]  ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4472)
[   15.280650][  T256]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[   15.280654][  T256]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   15.280658][  T256] RIP: 0033:0x7fd7dd70d120
[   15.280663][  T256] Code: ff ff 64 89 02 eb bd 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 1d 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 68 c3 0f 1f 80 00 00 00 00 41 54 48 83 ec 20
All code
========
   0:	ff                   	(bad)
   1:	ff 64 89 02          	jmp    *0x2(%rcx,%rcx,4)
   5:	eb bd                	jmp    0xffffffffffffffc4
   7:	0f 1f 00             	nopl   (%rax)
   a:	f3 0f 1e fa          	endbr64
   e:	41 89 ca             	mov    %ecx,%r10d
  11:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  18:	00 
  19:	85 c0                	test   %eax,%eax
  1b:	75 1d                	jne    0x3a
  1d:	45 31 c9             	xor    %r9d,%r9d
  20:	45 31 c0             	xor    %r8d,%r8d
  23:	b8 2c 00 00 00       	mov    $0x2c,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 68                	ja     0x9a
  32:	c3                   	ret
  33:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  3a:	41 54                	push   %r12
  3c:	48 83 ec 20          	sub    $0x20,%rsp

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 68                	ja     0x70
   8:	c3                   	ret
   9:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  10:	41 54                	push   %r12
  12:	48 83 ec 20          	sub    $0x20,%rsp
[   15.280666][  T256] RSP: 002b:00007ffef8c51f28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[   15.280670][  T256] RAX: ffffffffffffffda RBX: 0000000000000030 RCX: 00007fd7dd70d120
[   15.280673][  T256] RDX: 0000000000000030 RSI: 00007ffef8c51f30 RDI: 0000000000000005
[   15.280674][  T256] RBP: 00000000004047d0 R08: 0000000000000000 R09: 0000000000000000
[   15.280676][  T256] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
[   15.280678][  T256] R13: 00007ffef8c51f30 R14: 00007fd7dd5f9000 R15: 0000000000407160
| [   15.310750][  T256] refcount_t: underflow; use-after-free.
| [   15.311436][  T256] WARNING: CPU: 2 PID: 256 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3))
| [   15.311800][  T256] Modules linked in:
| [   15.312368][  T256] Tainted: [B]=BAD_PAGE
[   15.312527][  T256] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   15.312799][  T256] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3))
[   15.313066][  T256] Code: cc 38 03 80 fb 01 0f 87 29 33 d7 fe 83 e3 01 0f 85 51 ff ff ff c6 05 17 cc 38 03 01 90 48 c7 c7 40 ba a5 9a e8 62 d6 16 ff 90 <0f> 0b 90 90 e9 33 ff ff ff 48 89 df e8 c0 9d a0 ff e9 ba fe ff ff
All code
========
   0:	cc                   	int3
   1:	38 03                	cmp    %al,(%rbx)
   3:	80 fb 01             	cmp    $0x1,%bl
   6:	0f 87 29 33 d7 fe    	ja     0xfffffffffed73335
   c:	83 e3 01             	and    $0x1,%ebx
   f:	0f 85 51 ff ff ff    	jne    0xffffffffffffff66
  15:	c6 05 17 cc 38 03 01 	movb   $0x1,0x338cc17(%rip)        # 0x338cc33
  1c:	90                   	nop
  1d:	48 c7 c7 40 ba a5 9a 	mov    $0xffffffff9aa5ba40,%rdi
  24:	e8 62 d6 16 ff       	call   0xffffffffff16d68b
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	e9 33 ff ff ff       	jmp    0xffffffffffffff66
  33:	48 89 df             	mov    %rbx,%rdi
  36:	e8 c0 9d a0 ff       	call   0xffffffffffa09dfb
  3b:	e9 ba fe ff ff       	jmp    0xfffffffffffffefa

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	e9 33 ff ff ff       	jmp    0xffffffffffffff3c
   9:	48 89 df             	mov    %rbx,%rdi
   c:	e8 c0 9d a0 ff       	call   0xffffffffffa09dd1
  11:	e9 ba fe ff ff       	jmp    0xfffffffffffffed0
[   15.313752][  T256] RSP: 0018:ffffc90000b473f0 EFLAGS: 00010286
[   15.314022][  T256] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[   15.314318][  T256] RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000001
[   15.314612][  T256] RBP: 0000000000000003 R08: 0000000000000000 R09: fffffbfff3740934
[   15.314933][  T256] R10: 0000000000000003 R11: ffffc90000b46f80 R12: 0000000000000001
[   15.315224][  T256] R13: dffffc0000000000 R14: dead000000000122 R15: dead000000000100
[   15.315715][  T256] FS:  00007fd7dd5fab80(0000) GS:ffff8880d0208000(0000) knlGS:0000000000000000
[   15.316084][  T256] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   15.316347][  T256] CR2: 00000000004070d8 CR3: 000000000e965004 CR4: 0000000000772ef0
[   15.316643][  T256] PKRU: 55555554
[   15.316811][  T256] Call Trace:
[   15.317002][  T256]  <TASK>
[   15.317117][  T256]  netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11670)
[   15.317340][  T256]  ? dev_ingress_queue_create (net/core/dev.c:12299)
[   15.317566][  T256]  ? generic_xdp_install (net/core/dev.c:11630)
[   15.317775][  T256]  ? __netdev_upper_dev_unlink (net/core/dev.c:8973)
[   15.318048][  T256]  rtnl_dellink (net/core/rtnetlink.c:3580)
[   15.318262][  T256]  ? valid_bridge_getlink_req.constprop.0 (net/core/rtnetlink.c:3536)
[   15.318529][  T256]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   15.318748][  T256]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   15.318995][  T256]  ? find_held_lock (kernel/locking/lockdep.c:5350)
[   15.319202][  T256]  ? rtnetlink_rcv_msg (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 net/core/rtnetlink.c:6956)
[   15.319413][  T256]  ? __lock_release (kernel/locking/lockdep.c:5536)
[   15.319744][  T256]  ? valid_bridge_getlink_req.constprop.0 (net/core/rtnetlink.c:3536)
[   15.320108][  T256]  rtnetlink_rcv_msg (net/core/rtnetlink.c:6958)
[   15.320336][  T256]  ? rtnl_port_fill (net/core/rtnetlink.c:6861)
[   15.320542][  T256]  ? __lock_acquire (kernel/locking/lockdep.c:5237)
[   15.320743][  T256]  netlink_rcv_skb (net/netlink/af_netlink.c:2550)
[   15.320970][  T256]  ? rtnl_port_fill (net/core/rtnetlink.c:6861)
[   15.321174][  T256]  ? netlink_ack (net/netlink/af_netlink.c:2527)
[   15.321385][  T256]  ? netlink_deliver_tap (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:897 net/netlink/af_netlink.c:340)
[   15.321583][  T256]  ? 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)
[   15.321909][  T256]  netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
[   15.322120][  T256]  ? netlink_attachskb (net/netlink/af_netlink.c:1329)
[   15.322335][  T256]  ? netlink_insert (net/netlink/af_netlink.c:591 (discriminator 3))
[   15.322539][  T256]  ? netlink_autobind.isra.0 (net/netlink/af_netlink.c:804)
[   15.322737][  T256]  ? netlink_autobind.isra.0 (net/netlink/af_netlink.c:827)
[   15.322968][  T256]  netlink_sendmsg (net/netlink/af_netlink.c:1894)
[   15.323170][  T256]  ? netlink_unicast (net/netlink/af_netlink.c:1813)
[   15.323386][  T256]  ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4472)
[   15.323599][  T256]  ? lockdep_init_map_type (kernel/locking/lockdep.c:4973)
[   15.323811][  T256]  __sys_sendto (net/socket.c:727 net/socket.c:742 net/socket.c:2244)
[   15.324031][  T256]  ? __ia32_sys_getpeername (net/socket.c:2211)
[   15.324232][  T256]  ? fd_install (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:979 fs/file.c:676)
[   15.324477][  T256]  ? __lock_release (kernel/locking/lockdep.c:5536)
[   15.324696][  T256]  ? fd_install (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:979 fs/file.c:676)
[   15.324929][  T256]  ? fd_install (./arch/x86/include/asm/preempt.h:104 ./include/linux/rcupdate.h:981 fs/file.c:676)
[   15.325129][  T256]  ? __sys_socket (net/socket.c:516 net/socket.c:1756)
[   15.325344][  T256]  ? update_socket_protocol+0x10/0x10
[   15.325540][  T256]  ? xfd_validate_state (arch/x86/kernel/fpu/xstate.c:1499 arch/x86/kernel/fpu/xstate.c:1543)
[   15.325754][  T256]  __x64_sys_sendto (net/socket.c:2247)
[   15.325988][  T256]  ? do_syscall_64 (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 ./include/linux/entry-common.h:124 arch/x86/entry/syscall_64.c:90)
[   15.326304][  T256]  ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4472)
[   15.326503][  T256]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[   15.326732][  T256]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   15.327008][  T256] RIP: 0033:0x7fd7dd70d120
[   15.327217][  T256] Code: ff ff 64 89 02 eb bd 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 1d 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 68 c3 0f 1f 80 00 00 00 00 41 54 48 83 ec 20
All code
========
   0:	ff                   	(bad)
   1:	ff 64 89 02          	jmp    *0x2(%rcx,%rcx,4)
   5:	eb bd                	jmp    0xffffffffffffffc4
   7:	0f 1f 00             	nopl   (%rax)
   a:	f3 0f 1e fa          	endbr64
   e:	41 89 ca             	mov    %ecx,%r10d
  11:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  18:	00 
  19:	85 c0                	test   %eax,%eax
  1b:	75 1d                	jne    0x3a
  1d:	45 31 c9             	xor    %r9d,%r9d
  20:	45 31 c0             	xor    %r8d,%r8d
  23:	b8 2c 00 00 00       	mov    $0x2c,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 68                	ja     0x9a
  32:	c3                   	ret
  33:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  3a:	41 54                	push   %r12
  3c:	48 83 ec 20          	sub    $0x20,%rsp

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 68                	ja     0x70
   8:	c3                   	ret
   9:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  10:	41 54                	push   %r12
  12:	48 83 ec 20          	sub    $0x20,%rsp
[   15.328038][  T256] RSP: 002b:00007ffef8c51f28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[   15.328354][  T256] RAX: ffffffffffffffda RBX: 0000000000000030 RCX: 00007fd7dd70d120
[   15.328661][  T256] RDX: 0000000000000030 RSI: 00007ffef8c51f30 RDI: 0000000000000005
[   15.329195][  T256] RBP: 00000000004047d0 R08: 0000000000000000 R09: 0000000000000000
[   15.329514][  T256] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005


Finger prints:
print_report:kasan_report:kobject_put:netdev_run_todo:rtnl_dellink
refcount_warn_saturate:netdev_run_todo:rtnl_dellink:rtnetlink_rcv_msg:netlink_rcv_skb