XFS (loop0): Invalid superblock magic number 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: 11080 Comm: blkid Not tainted 4.14.160-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff88804b276540 task.stack: ffff88804d728000 RIP: 0010:kobject_uevent_env+0xa1/0xc23 lib/kobject_uevent.c:350 RSP: 0018:ffff88804d72fb60 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: 0000000000000002 RCX: 1ffff1100964edb6 RDX: 0000000000000014 RSI: 0000000000000002 RDI: ffffffff8770dd50 RBP: ffff88804d72fbe0 R08: ffff88804b276540 R09: 0000000000000003 R10: 0000000000000000 R11: ffff88804b276540 R12: 00000000000000a0 R13: 0000000000000002 R14: ffff8880a6e5e140 R15: 00000000000000a0 FS: 00007fa74a7f8740(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c43fd0cbe0 CR3: 000000007f39b000 CR4: 00000000001406f0 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:1650 [inline] lo_release+0x112/0x1b0 drivers/block/loop.c:1668 __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: 0033:0x7fa74a1002b0 RSP: 002b:00007fff7850c7b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fa74a1002b0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000028 R09: 0000000001680000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000001ca9030 R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005 Code: fa 83 e2 07 38 d0 7f 09 84 c0 74 05 e8 8f da 28 fb 41 80 4f 3c 08 e8 c5 4c fe fa 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 27 da 28 fb 49 8b 37 48 c7 c1 40 RIP: kobject_uevent_env+0xa1/0xc23 lib/kobject_uevent.c:350 RSP: ffff88804d72fb60 ---[ end trace e36ed003d8040674 ]---