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
Modules linked in:
CPU: 0 PID: 17646 Comm: blkid Not tainted 4.14.169-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888062e42600 task.stack: ffff888089df8000
RIP: 0010:kobject_uevent_env+0xa4/0xc80 lib/kobject_uevent.c:355
RSP: 0018:ffff888089dffb60 EFLAGS: 00010206
RAX: 0000000000000018 RBX: ffff888094ad4480 RCX: 1ffff1100c5c85ce
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000000000c0
RBP: ffff888089dffbe0 R08: ffff888062e42600 R09: 0000000000000003
R10: 0000000000000000 R11: ffff888062e42600 R12: dffffc0000000000
R13: 00000000000000a0 R14: 00000000000000a0 R15: ffff888094ad45c8
FS:  00007f9ea4de1740(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fd24000 CR3: 0000000090f69000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kobject_uevent+0x20/0x30 lib/kobject_uevent.c:553
 loop_clr_fd+0x4a7/0xae0 drivers/block/loop.c:1069
 __lo_release drivers/block/loop.c:1660 [inline]
 lo_release+0x112/0x1b0 drivers/block/loop.c:1678
 __blkdev_put+0x434/0x7f0 fs/block_dev.c:1791
 blkdev_put+0x88/0x510 fs/block_dev.c:1856
 blkdev_close+0x8b/0xb0 fs/block_dev.c:1863
 __fput+0x275/0x7a0 fs/file_table.c:210
 ____fput+0x16/0x20 fs/file_table.c:244
 task_work_run+0x114/0x190 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x1da/0x220 arch/x86/entry/common.c:164
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f9ea46e92b0
RSP: 002b:00007ffcc73c3d78 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f9ea46e92b0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000028 R09: 0000000001680000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000023dc030
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005
Code: c1 e8 03 42 80 3c 20 00 0f 85 6c 0a 00 00 4d 8b 76 18 4d 85 f6 0f 84 27 02 00 00 e8 f7 f1 f9 fa 49 8d 7e 20 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 0f 85 3a 0a 00 00 4d 8b 7e 20 4d 85 ff 74 b4 e8 
RIP: kobject_uevent_env+0xa4/0xc80 lib/kobject_uevent.c:355 RSP: ffff888089dffb60
---[ end trace 6f7b45d6d8ed5b36 ]---