general protection fault in bd_set_size

[syzbot]

Hello,

syzkaller hit the following crash on
ae59df0349baf44c988b32a3b4dc21363d87df15
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.




kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
(ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 22872 Comm: syz-executor7 Not tainted 4.14.0-rc6+ #56
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
task: ffff8801d5e40700 task.stack: ffff8801cd3b0000
RIP: 0010:bdev_get_queue include/linux/blkdev.h:997 [inline]
RIP: 0010:bdev_logical_block_size include/linux/blkdev.h:1433 [inline]
RIP: 0010:bd_set_size+0x5f/0x330 fs/block_dev.c:1395
RSP: 0018:ffff8801cd3b7058 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff10039a76df2
RDX: 00000000000000aa RSI: 0000000000000000 RDI: 0000000000000550
RBP: ffff8801cd3b7088 R08: ffff8801d0869260 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801da805040
R13: 0000000000000000 R14: ffff8801d5a004c0 R15: ffff8801d5a007e8
FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000002001d004 CR3: 0000000005a22000 CR4: 00000000001406e0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
loop_clr_fd+0x4fc/0xb50 drivers/block/loop.c:1048
lo_release+0xee/0x180 drivers/block/loop.c:1593
__blkdev_put+0x602/0x7c0 fs/block_dev.c:1782
blkdev_put+0x85/0x4f0 fs/block_dev.c:1847
blkdev_close+0x8b/0xb0 fs/block_dev.c:1854
__fput+0x327/0x7e0 fs/file_table.c:210
____fput+0x15/0x20 fs/file_table.c:244
task_work_run+0x199/0x270 kernel/task_work.c:112
exit_task_work include/linux/task_work.h:21 [inline]
do_exit+0x9b5/0x1ad0 kernel/exit.c:865
do_group_exit+0x149/0x400 kernel/exit.c:968
get_signal+0x73f/0x16d0 kernel/signal.c:2334
do_signal+0x94/0x1ee0 arch/x86/kernel/signal.c:808
exit_to_usermode_loop+0x214/0x310 arch/x86/entry/common.c:158
prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
syscall_return_slowpath arch/x86/entry/common.c:266 [inline]
do_syscall_32_irqs_on arch/x86/entry/common.c:335 [inline]
do_fast_syscall_32+0x83e/0xf05 arch/x86/entry/common.c:391
entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:124
RIP: 0023:0xf7f30c79
RSP: 002b:00000000f772c01c EFLAGS: 00000296 ORIG_RAX: 00000000000000bb
RAX: 0000000000000001 RBX: 0000000000000020 RCX: 0000000000000021
RDX: 00000000200ddff8 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Code: 03 80 3c 02 00 0f 85 c6 02 00 00 49 8b 9c 24 e0 00 00 00 48 b8 00 00
00 00 00 fc ff df 48 8d bb 50 05 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00
0f 85 76 02 00 00 4d 8d 74 24 08 48 b8 00 00 00 00
RIP: bdev_get_queue include/linux/blkdev.h:997 [inline] RSP:
ffff8801cd3b7058
RIP: bdev_logical_block_size include/linux/blkdev.h:1433 [inline] RSP:
ffff8801cd3b7058
RIP: bd_set_size+0x5f/0x330 fs/block_dev.c:1395 RSP: ffff8801cd3b7058
---[ end trace 900b89018bbb98a6 ]---


---
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[syzbot]

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