netlink: 4 bytes leftover after parsing attributes in process `syz.0.4279'.
INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 0 UID: 0 PID: 21952 Comm: syz.0.4279 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 assign_lock_key+0x133/0x150
 register_lock_class+0xcc/0x2e0
 __lock_acquire+0xab/0x2cf0
 lock_acquire+0x106/0x350
 _raw_spin_lock+0x2e/0x40
 nfsd4_cancel_copy_by_sb+0x10d/0x840
 nfsd_nl_unlock_filesystem_doit+0x248/0x370
 genl_family_rcv_msg_doit+0x233/0x340
 genl_rcv_msg+0x614/0x7a0
 netlink_rcv_skb+0x226/0x4a0
 genl_rcv+0x28/0x40
 netlink_unicast+0x7bb/0x940
 netlink_sendmsg+0x813/0xb40
 sock_sendmsg_nosec+0x13a/0x180
 ____sys_sendmsg+0x54e/0x850
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1b1/0x290
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd43a59ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd43b41f028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd43a815fa0 RCX: 00007fd43a59ce59
RDX: 0000000004000080 RSI: 0000200000000100 RDI: 0000000000000005
RBP: 00007fd43a632e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd43a816038 R14: 00007fd43a815fa0 R15: 00007ffe9a8c3888
 </TASK>
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 21952 Comm: syz.0.4279 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:nfsd4_cancel_copy_by_sb+0x161/0x840
Code: 48 42 80 3c 31 00 74 0f 48 8b 7c 24 10 e8 d7 cf 4c ff 48 8b 44 24 10 48 8b 5c 24 18 48 c1 e3 04 48 03 18 48 89 d8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 df e8 b0 cf 4c ff 48 8b 03 48 39 d8 48
RSP: 0018:ffffc90004dcf280 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffff11037c9d00d
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90004dcf200
RBP: ffffc90004dcf370 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520009b9e40 R12: ffffc90004dcf300
R13: 1ffff920009b9e98 R14: dffffc0000000000 R15: 1ffff920009b9e5c
FS:  00007fd43b41f6c0(0000) GS:ffff88818dc25000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000010de4a000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 nfsd_nl_unlock_filesystem_doit+0x248/0x370
 genl_family_rcv_msg_doit+0x233/0x340
 genl_rcv_msg+0x614/0x7a0
 netlink_rcv_skb+0x226/0x4a0
 genl_rcv+0x28/0x40
 netlink_unicast+0x7bb/0x940
 netlink_sendmsg+0x813/0xb40
 sock_sendmsg_nosec+0x13a/0x180
 ____sys_sendmsg+0x54e/0x850
 ___sys_sendmsg+0x2a5/0x360
 __x64_sys_sendmsg+0x1b1/0x290
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd43a59ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd43b41f028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd43a815fa0 RCX: 00007fd43a59ce59
RDX: 0000000004000080 RSI: 0000200000000100 RDI: 0000000000000005
RBP: 00007fd43a632e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd43a816038 R14: 00007fd43a815fa0 R15: 00007ffe9a8c3888
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:nfsd4_cancel_copy_by_sb+0x161/0x840
Code: 48 42 80 3c 31 00 74 0f 48 8b 7c 24 10 e8 d7 cf 4c ff 48 8b 44 24 10 48 8b 5c 24 18 48 c1 e3 04 48 03 18 48 89 d8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 df e8 b0 cf 4c ff 48 8b 03 48 39 d8 48
RSP: 0018:ffffc90004dcf280 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffff11037c9d00d
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90004dcf200
RBP: ffffc90004dcf370 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520009b9e40 R12: ffffc90004dcf300
R13: 1ffff920009b9e98 R14: dffffc0000000000 R15: 1ffff920009b9e5c
FS:  00007fd43b41f6c0(0000) GS:ffff88818dc25000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000010de4a000 CR4: 00000000000006f0
