------------[ cut here ]------------
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 0 PID: 22847 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Modules linked in:
CPU: 0 PID: 22847 Comm: kworker/u4:5 Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Code: 1d 9e 9c 81 09 31 ff 89 de e8 6d 11 9d fd 84 db 75 e0 e8 84 0d 9d fd 48 c7 c7 60 cb e4 89 c6 05 7e 9c 81 09 01 e8 78 77 1c 05 <0f> 0b eb c4 e8 68 0d 9d fd 0f b6 1d 6d 9c 81 09 31 ff 89 de e8 38
RSP: 0018:ffffc90000007df0 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88801fd69d00 RSI: ffffffff815f39c8 RDI: fffff52000000fb0
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815ed79e R11: 0000000000000000 R12: 0000000000000001
R13: ffff88801a4fc5b0 R14: 0000000000000007 R15: ffff88801a7f59e8
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbd3c3f8134 CR3: 000000000b68e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __refcount_dec include/linux/refcount.h:344 [inline]
 refcount_dec include/linux/refcount.h:359 [inline]
 dev_put include/linux/netdevice.h:4166 [inline]
 in_dev_finish_destroy+0x160/0x1b0 net/ipv4/devinet.c:246
 in_dev_put include/linux/inetdevice.h:276 [inline]
 in_dev_rcu_put+0x83/0xb0 net/ipv4/devinet.c:303
 rcu_do_batch kernel/rcu/tree.c:2506 [inline]
 rcu_core+0x7ab/0x1470 kernel/rcu/tree.c:2741
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_release+0x3f1/0x720 kernel/locking/lockdep.c:5645
Code: 7e 83 f8 01 0f 85 8d 01 00 00 9c 58 f6 c4 02 0f 85 78 01 00 00 48 f7 04 24 00 02 00 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c5 48 c7 45 00 00 00 00 00 c7 45 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc90005057690 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 3f947b2de208ab16 RCX: ffffc900050576e0
RDX: 1ffff11003fad4ea RSI: 0000000000000000 RDI: 0000000000000000
RBP: 1ffff92000a0aed4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000004
R13: 0000000000000005 R14: ffff88801fd6a758 R15: ffff88801fd69d00
 kernfs_drain fs/kernfs/dir.c:481 [inline]
 __kernfs_remove+0x8ce/0xab0 fs/kernfs/dir.c:1351
 kernfs_remove_by_name_ns+0x4f/0xa0 fs/kernfs/dir.c:1544
 kernfs_remove_by_name include/linux/kernfs.h:570 [inline]
 remove_files+0x96/0x1c0 fs/sysfs/group.c:28
 sysfs_remove_group+0x87/0x170 fs/sysfs/group.c:288
 sysfs_remove_groups fs/sysfs/group.c:312 [inline]
 sysfs_remove_groups+0x5c/0xa0 fs/sysfs/group.c:304
 device_remove_groups drivers/base/core.c:2480 [inline]
 device_remove_attrs+0x134/0x170 drivers/base/core.c:2686
 device_del+0x4fa/0xd60 drivers/base/core.c:3580
 unregister_netdevice_many+0xd1f/0x1790 net/core/dev.c:11104
 default_device_exit_batch+0x2fa/0x3c0 net/core/dev.c:11607
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171
 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:593
 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
----------------
Code disassembly (best guess):
   0:	7e 83                	jle    0xffffff85
   2:	f8                   	clc
   3:	01 0f                	add    %ecx,(%rdi)
   5:	85 8d 01 00 00 9c    	test   %ecx,-0x63ffffff(%rbp)
   b:	58                   	pop    %rax
   c:	f6 c4 02             	test   $0x2,%ah
   f:	0f 85 78 01 00 00    	jne    0x18d
  15:	48 f7 04 24 00 02 00 	testq  $0x200,(%rsp)
  1c:	00
  1d:	74 01                	je     0x20
  1f:	fb                   	sti
  20:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  27:	fc ff df
* 2a:	48 01 c5             	add    %rax,%rbp <-- trapping instruction
  2d:	48 c7 45 00 00 00 00 	movq   $0x0,0x0(%rbp)
  34:	00
  35:	c7 45 08 00 00 00 00 	movl   $0x0,0x8(%rbp)
  3c:	48                   	rex.W
  3d:	8b                   	.byte 0x8b
  3e:	84                   	.byte 0x84
  3f:	24                   	.byte 0x24