general protection fault in bd_set_size

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: d33692e8 Merge 4.14.74 into android-4.14
git tree: android-4.14
console output: https://syzkaller.appspot.com/x/log.txt?x=177aaaa1400000
kernel config: https://syzkaller.appspot.com/x/.config?x=decf36ad71cd0a75
dashboard link: https://syzkaller.appspot.com/bug?extid=1af161f9dc37d795c196
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1795f4e9400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+1af161...@syzkaller.appspotmail.com

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN NOPTI
Modules linked in:
CPU: 0 PID: 4812 Comm: blkid Not tainted 4.14.74+ #17
task: ffff8801c538af00 task.stack: ffff8801d44b0000
RIP: 0010:bdev_get_queue include/linux/blkdev.h:1015 [inline]
RIP: 0010:bdev_logical_block_size include/linux/blkdev.h:1451 [inline]
RIP: 0010:bd_set_size+0x58/0x320 fs/block_dev.c:1396
RSP: 0018:ffff8801d44b7c78 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff10038a716e5
RDX: 00000000000000a7 RSI: 0000000000000000 RDI: 0000000000000538
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d53f3980
R13: ffff8801d53f3980 R14: ffff8801cd6db2c8 R15: ffff8801cd6db4a8
FS: 00007f82777c3740(0000) GS:ffff8801dba00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0d437bf6f0 CR3: 00000001d6098002 CR4: 00000000001606b0
Call Trace:
loop_clr_fd+0x465/0xac0 drivers/block/loop.c:1057
__lo_release drivers/block/loop.c:1618 [inline]
lo_release+0xfd/0x190 drivers/block/loop.c:1636
__blkdev_put+0x526/0x6e0 fs/block_dev.c:1783
blkdev_close+0x86/0xb0 fs/block_dev.c:1855
__fput+0x25e/0x6f0 fs/file_table.c:210
task_work_run+0x116/0x190 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:191 [inline]
exit_to_usermode_loop+0x12e/0x150 arch/x86/entry/common.c:163
prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
syscall_return_slowpath arch/x86/entry/common.c:267 [inline]
do_syscall_64+0x35d/0x4b0 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f82770cb2b0
RSP: 002b:00007ffc5935b6e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f82770cb2b0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000028 R09: 0000000001680000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000012df030
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005
Code: 03 80 3c 02 00 0f 85 a4 02 00 00 49 8b 9c 24 e0 00 00 00 48 b8 00 00
00 00 00 fc ff df 48 8d bb 38 05 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00
0f 85 70 02 00 00 4d 8d 6c 24 08 48 8b 9b 38 05 00
RIP: bdev_get_queue include/linux/blkdev.h:1015 [inline] RSP:
ffff8801d44b7c78
RIP: bdev_logical_block_size include/linux/blkdev.h:1451 [inline] RSP:
ffff8801d44b7c78
RIP: bd_set_size+0x58/0x320 fs/block_dev.c:1396 RSP: ffff8801d44b7c78
---[ end trace b30f3181cdad60ae ]---


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches