BUG: unable to handle kernel paging request in lock_sock_nested

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f79dc860 Linux 4.14.215
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15f62a3f500000
kernel config: https://syzkaller.appspot.com/x/.config?x=9844af499cbb61c0
dashboard link: https://syzkaller.appspot.com/bug?extid=20000683154c019ac49c
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+200006...@syzkaller.appspotmail.com

ip6_tables: ip6tables: counters copy to user failed while replacing table
ldm_validate_privheads(): Disk read failed.
Dev loop5: unable to read RDB block 5
loop5: unable to read partition table
loop5: partition table beyond EOD, truncated
BUG: unable to handle kernel paging request at 00000000029c2c6b
IP: atomic_inc arch/x86/include/asm/atomic.h:92 [inline]
IP: __lock_acquire+0x21e/0x3f20 kernel/locking/lockdep.c:3382
PGD 0 P4D 0
Oops: 0002 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 20185 Comm: syz-executor.0 Not tainted 4.14.215-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888061442380 task.stack: ffff8880617a8000
RIP: 0010:atomic_inc arch/x86/include/asm/atomic.h:92 [inline]
RIP: 0010:__lock_acquire+0x21e/0x3f20 kernel/locking/lockdep.c:3382
RSP: 0018:ffff8880617af598 EFLAGS: 00010006
RAX: 00000000029c2b33 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 1ffff110151f8e4d RSI: 0000000000000000 RDI: ffff8880a8fc7268
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffff888061442380 R12: ffff8880a8fc7260
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff8beb5d40
FS: 00007fa567e69700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000029c2c6b CR3: 0000000008e6a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:176
spin_lock_bh include/linux/spinlock.h:322 [inline]
lock_sock_nested+0x39/0x100 net/core/sock.c:2788
l2cap_sock_teardown_cb+0x93/0x650 net/bluetooth/l2cap_sock.c:1341
l2cap_chan_del+0xaf/0x950 net/bluetooth/l2cap_core.c:599
l2cap_conn_del+0x36e/0x690 net/bluetooth/l2cap_core.c:1729
l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7441 [inline]
l2cap_disconn_cfm+0x7c/0xb0 net/bluetooth/l2cap_core.c:7434
hci_disconn_cfm include/net/bluetooth/hci_core.h:1226 [inline]
hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1393
hci_dev_do_close+0x535/0xca0 net/bluetooth/hci_core.c:1620
hci_unregister_dev+0x17f/0x8c0 net/bluetooth/hci_core.c:3191
vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:354
__fput+0x25f/0x7a0 fs/file_table.c:210
task_work_run+0x11f/0x190 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0xa44/0x2850 kernel/exit.c:868
do_group_exit+0x100/0x2e0 kernel/exit.c:965
get_signal+0x38d/0x1ca0 kernel/signal.c:2423
do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:814
exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160
prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45e219
RSP: 002b:00007fa567e68c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: 0000000001000000 RBX: 0000000000000003 RCX: 000000000045e219
RDX: 00000000fffffd2c RSI: 0000000020000000 RDI: 0000000000000006
RBP: 000000000119c068 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c034
R13: 00007ffe89c534cf R14: 00007fa567e699c0 R15: 000000000119c034
Code: 00 fc ff df 41 89 f6 4b 8d 7c f4 08 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 5e 2a 00 00 4b 8b 44 f4 08 48 85 c0 0f 84 31 ff ff ff <f0> ff 80 38 01 00 00 49 8d b3 80 08 00 00 48 ba 00 00 00 00 00
RIP: atomic_inc arch/x86/include/asm/atomic.h:92 [inline] RSP: ffff8880617af598
RIP: __lock_acquire+0x21e/0x3f20 kernel/locking/lockdep.c:3382 RSP: ffff8880617af598
CR2: 00000000029c2c6b
---[ end trace 9b9171f6fd7eba61 ]---


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[syzbot]

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