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bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
bond0 (unregistering): Released all slaves
BUG: kernel NULL pointer dereference, address: 000000000000009c
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 126f82067 P4D 126f82067 PUD 126f8f067 PMD 0 
Oops: 0000 [#1] SMP
CPU: 1 PID: 902 Comm: kworker/u4:16 Not tainted 5.10.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:afs_unuse_cell+0x67/0x780 fs/afs/cell.c:592
Code: 4d 8b 6f 08 45 8b a7 88 0c 00 00 41 8b 87 90 0c 00 00 89 45 d4 e8 b9 d7 78 fd 49 8d 9e 9c 00 00 00 4d 85 ed 0f 85 30 04 00 00 <41> 8b 86 9c 00 00 00 89 45 8c 48 89 df e8 a7 f8 f7 fd 8b 18 8b 0a
RSP: 0018:ffff888104597a38 EFLAGS: 00010246
RAX: ffffffff843e3717 RBX: 000000000000009c RCX: ffff888105c83d80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888114ed4000
RBP: ffff888104597ac0 R08: ffffea000000000f R09: ffff88813fffa000
R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffff888105c84780
FS:  0000000000000000(0000) GS:ffff88813fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000009c CR3: 00000001203d8000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 afs_cell_purge+0xfb/0x5e0 fs/afs/cell.c:951
 afs_net_exit+0xc6/0x180 fs/afs/main.c:156
 ops_exit_list net/core/net_namespace.c:187 [inline]
 cleanup_net+0xd73/0x1af0 net/core/net_namespace.c:604
 process_one_work+0x121c/0x1fc0 kernel/workqueue.c:2272
 worker_thread+0x10cc/0x2740 kernel/workqueue.c:2418
 kthread+0x51c/0x560 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
Modules linked in:
CR2: 000000000000009c
---[ end trace d59125f802b26595 ]---
RIP: 0010:afs_unuse_cell+0x67/0x780 fs/afs/cell.c:592
Code: 4d 8b 6f 08 45 8b a7 88 0c 00 00 41 8b 87 90 0c 00 00 89 45 d4 e8 b9 d7 78 fd 49 8d 9e 9c 00 00 00 4d 85 ed 0f 85 30 04 00 00 <41> 8b 86 9c 00 00 00 89 45 8c 48 89 df e8 a7 f8 f7 fd 8b 18 8b 0a
RSP: 0018:ffff888104597a38 EFLAGS: 00010246
RAX: ffffffff843e3717 RBX: 000000000000009c RCX: ffff888105c83d80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888114ed4000
RBP: ffff888104597ac0 R08: ffffea000000000f R09: ffff88813fffa000
R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffff888105c84780
FS:  0000000000000000(0000) GS:ffff88813fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000009c CR3: 00000001203d8000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400