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: 1949 Comm: syz-executor.5 Not tainted 4.14.160-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888052e9c4c0 task.stack: ffff888212130000
RIP: 0010:cgroup_root_from_kf kernel/cgroup/cgroup.c:1178 [inline]
RIP: 0010:cgroup_kill_sb+0x2e/0x330 kernel/cgroup/cgroup.c:2035
RSP: 0018:ffff888212137ac0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000fffffff4 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff81ac3c8c RDI: ffff88802dbfc4b0
RBP: ffff888212137ae0 R08: ffff888052e9c4c0 R09: ffff888052e9cd60
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88802dbfc480
R13: ffffffff87fa6f40 R14: ffff88802dbfc480 R15: dffffc0000000000
FS:  00007fbc0ec7d700(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000075c000 CR3: 00000001ed69c000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 deactivate_locked_super+0x74/0xe0 fs/super.c:319
 sget_userns+0x9d9/0xc30 fs/super.c:537
 kernfs_mount_ns+0xe9/0x790 fs/kernfs/mount.c:324
 kernfs_mount include/linux/kernfs.h:544 [inline]
 cgroup_do_mount+0x9e/0x270 kernel/cgroup/cgroup.c:1952
 cgroup_mount+0x26d/0x8c0 kernel/cgroup/cgroup.c:2019
 mount_fs+0x97/0x2a1 fs/super.c:1237
 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2549 [inline]
 do_mount+0x417/0x27d0 fs/namespace.c:2879
 SYSC_mount fs/namespace.c:3095 [inline]
 SyS_mount+0xab/0x120 fs/namespace.c:3072
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a919
RSP: 002b:00007fbc0ec7cc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fbc0ec7cc90 RCX: 000000000045a919
RDX: 0000000020000200 RSI: 0000000020000100 RDI: 0000000000000000
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbc0ec7d6d4
R13: 00000000004c7d30 R14: 00000000004dec28 R15: 0000000000000005
Code: e5 41 55 41 54 49 89 fc 53 48 83 ec 08 e8 4b 28 06 00 4c 89 e7 e8 23 15 55 00 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 c1 e9 03 <80> 3c 11 00 0f 85 c4 02 00 00 48 8b 18 48 b8 00 00 00 00 00 fc 
RIP: cgroup_root_from_kf kernel/cgroup/cgroup.c:1178 [inline] RSP: ffff888212137ac0
RIP: cgroup_kill_sb+0x2e/0x330 kernel/cgroup/cgroup.c:2035 RSP: ffff888212137ac0
---[ end trace a013d8185111a1ac ]---
kobject: 'loop4' (ffff8880a412cea0): kobject_uevent_env