syzbot

general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 3 PID: 8879 Comm: kworker/u16:0 Not tainted 6.4.0-syzkaller-01647-g6e2332e0ab53 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:tipc_conn_close+0x48/0x1c0 net/tipc/topsrv.c:158
Code: fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 63 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 5d 08 48 8d 7b 18 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 4d 01 00 00 4c 8b 6b 18 4d 8d a5 a0 03 00 00 4c
RSP: 0018:ffffc90004237bb8 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000003 RSI: ffffffff89b3b054 RDI: 0000000000000018
RBP: ffff88805c882400 R08: 0000000000000001 R09: ffffffff91532ecf
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88803ef2b058
R13: ffffed1007de5613 R14: ffff88805c882408 R15: ffff88805c882400
FS:  0000000000000000(0000) GS:ffff88806b900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000001 CR3: 00000000494b3000 CR4: 0000000000350ee0
DR0: 0000000000000000 DR1: 000000009aa44324 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 tipc_topsrv_stop net/tipc/topsrv.c:708 [inline]
 tipc_topsrv_exit_net+0x146/0x3b0 net/tipc/topsrv.c:730
 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:170
 cleanup_net+0x4ee/0xb10 net/core/net_namespace.c:614
 process_one_work+0xa34/0x16f0 kernel/workqueue.c:2597
 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2748
 kthread+0x344/0x440 kernel/kthread.c:389
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:tipc_conn_close+0x48/0x1c0 net/tipc/topsrv.c:158
Code: fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 63 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 5d 08 48 8d 7b 18 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 4d 01 00 00 4c 8b 6b 18 4d 8d a5 a0 03 00 00 4c
RSP: 0018:ffffc90004237bb8 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000003 RSI: ffffffff89b3b054 RDI: 0000000000000018
RBP: ffff88805c882400 R08: 0000000000000001 R09: ffffffff91532ecf
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88803ef2b058
R13: ffffed1007de5613 R14: ffff88805c882408 R15: ffff88805c882400
FS:  0000000000000000(0000) GS:ffff88806b900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f21c7b0e8c3 CR3: 00000000494b3000 CR4: 0000000000350ee0
DR0: 0000000000000000 DR1: 000000009aa44324 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 3 bytes skipped:
   0:	48 c1 ea 03          	shr    $0x3,%rdx
   4:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   8:	0f 85 63 01 00 00    	jne    0x171
   e:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  15:	fc ff df
  18:	48 8b 5d 08          	mov    0x8(%rbp),%rbx
  1c:	48 8d 7b 18          	lea    0x18(%rbx),%rdi
  20:	48 89 fa             	mov    %rdi,%rdx
  23:	48 c1 ea 03          	shr    $0x3,%rdx
* 27:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2b:	0f 85 4d 01 00 00    	jne    0x17e
  31:	4c 8b 6b 18          	mov    0x18(%rbx),%r13
  35:	4d 8d a5 a0 03 00 00 	lea    0x3a0(%r13),%r12
  3c:	4c                   	rex.WR