kernel BUG at lib/assoc_array.c:LINE! (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e8878ab8 Merge tag 'spi-fix-v5.9-rc4' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12892c11900000
kernel config: https://syzkaller.appspot.com/x/.config?x=c61610091f4ca8c4
dashboard link: https://syzkaller.appspot.com/bug?extid=5cb98ddf89ec01d73c6d
compiler: gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5cb98d...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at lib/assoc_array.c:652!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 7123 Comm: kworker/1:3 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: afs afs_manage_cell
RIP: 0010:assoc_array_insert_into_terminal_node lib/assoc_array.c:652 [inline]
RIP: 0010:assoc_array_insert+0x1cbe/0x2a80 lib/assoc_array.c:1001
Code: 0f 84 cd fe ff ff e8 e1 62 15 fe e9 c3 fe ff ff e8 57 5c d5 fd 0f 0b e8 50 5c d5 fd 0f 0b e8 49 5c d5 fd 0f 0b e8 42 5c d5 fd <0f> 0b 48 8b 04 24 4c 89 74 24 70 48 b9 00 00 00 00 00 fc ff df 41
RSP: 0018:ffffc900054977a0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 000000000000000f RCX: ffffffff839eeb4c
RDX: ffff8880553a0540 RSI: ffffffff839ef13e RDI: ffff88804726f688
RBP: 0000000000000011 R08: 0000000000000dc0 R09: ffffffff8b177750
R10: 0000000000000010 R11: 000000000000016e R12: 0000000000000010
R13: ffff888053910000 R14: ffff888051e50101 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000768000 CR3: 000000009e098000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__key_link_begin+0xec/0x250 security/keys/keyring.c:1314
construct_alloc_key security/keys/request_key.c:404 [inline]
construct_key_and_link security/keys/request_key.c:499 [inline]
request_key_and_link+0x894/0x1350 security/keys/request_key.c:637
request_key_tag+0x4e/0xb0 security/keys/request_key.c:701
dns_query+0x257/0x6c3 net/dns_resolver/dns_query.c:128
afs_dns_query+0x122/0x390 fs/afs/addr_list.c:249
afs_update_cell fs/afs/cell.c:403 [inline]
afs_manage_cell+0x8c5/0x11c0 fs/afs/cell.c:708
process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Modules linked in:
---[ end trace 234f5667657c5700 ]---
RIP: 0010:assoc_array_insert_into_terminal_node lib/assoc_array.c:652 [inline]
RIP: 0010:assoc_array_insert+0x1cbe/0x2a80 lib/assoc_array.c:1001
Code: 0f 84 cd fe ff ff e8 e1 62 15 fe e9 c3 fe ff ff e8 57 5c d5 fd 0f 0b e8 50 5c d5 fd 0f 0b e8 49 5c d5 fd 0f 0b e8 42 5c d5 fd <0f> 0b 48 8b 04 24 4c 89 74 24 70 48 b9 00 00 00 00 00 fc ff df 41
RSP: 0018:ffffc900054977a0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 000000000000000f RCX: ffffffff839eeb4c
RDX: ffff8880553a0540 RSI: ffffffff839ef13e RDI: ffff88804726f688
RBP: 0000000000000011 R08: 0000000000000dc0 R09: ffffffff8b177750
R10: 0000000000000010 R11: 000000000000016e R12: 0000000000000010
R13: ffff888053910000 R14: ffff888051e50101 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f340d222000 CR3: 00000000a6f13000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.