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: 19923 Comm: blkid Not tainted 4.14.134 #29
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88805c856140 task.stack: ffff88805c080000
RIP: 0010:kobject_uevent_env+0xa1/0xc23 lib/kobject_uevent.c:350
RSP: 0018:ffff88805c087b60 EFLAGS: 00010286
RAX: dffffc0000000000 RBX: 0000000000000002 RCX: 1ffff1100b90ad36
RDX: 0000000000000014 RSI: 0000000000000002 RDI: ffffffff87077370
RBP: ffff88805c087be0 R08: ffff88805c856140 R09: 0000000000000003
R10: 0000000000000000 R11: ffff88805c856140 R12: 00000000000000a0
R13: 0000000000000002 R14: ffff888050ed9940 R15: 00000000000000a0
FS:  00007fa4cf43d740(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000004e299000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kobject_uevent+0x20/0x26 lib/kobject_uevent.c:553
 loop_clr_fd+0x4a7/0xae0 drivers/block/loop.c:1059
 __lo_release drivers/block/loop.c:1649 [inline]
 lo_release+0x112/0x1b0 drivers/block/loop.c:1667
 __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: 0033:0x7fa4ced452b0
RSP: 002b:00007ffd118231b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fa4ced452b0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000028 R09: 0000000001680000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000020c6030
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005
Code: fa 83 e2 07 38 d0 7f 09 84 c0 74 05 e8 9f 60 70 fb 41 80 4f 3c 08 e8 85 be 46 fb 4c 89 fa b8 ff ff 37 00 48 c1 ea 03 48 c1 e0 2a <80> 3c 02 00 74 08 4c 89 ff e8 37 60 70 fb 49 8b 37 48 c7 c1 60 
RIP: kobject_uevent_env+0xa1/0xc23 lib/kobject_uevent.c:350 RSP: ffff88805c087b60
---[ end trace 9aa33ff761156e5d ]---