Warning: Permanently added '10.128.10.25' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 27.099583] overlayfs: failed to create directory ./file1/work (errno: 30); mounting read-only [ 27.108588] [ 27.110204] ===================================== [ 27.115047] WARNING: bad unlock balance detected! [ 27.119861] 4.14.267-syzkaller #0 Not tainted [ 27.124321] ------------------------------------- [ 27.129133] syz-executor341/7962 is trying to release lock (sb_writers) at: [ 27.136212] [] ovl_workdir_create.cold+0xeb/0xf7 [ 27.142499] but there are no more locks to release! [ 27.147482] [ 27.147482] other info that might help us debug this: [ 27.154117] 1 lock held by syz-executor341/7962: [ 27.158837] #0: (&type->s_umount_key#46/1){+.+.}, at: [] sget_userns+0x556/0xc10 [ 27.168089] [ 27.168089] stack backtrace: [ 27.172557] CPU: 1 PID: 7962 Comm: syz-executor341 Not tainted 4.14.267-syzkaller #0 [ 27.180405] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.189732] Call Trace: [ 27.192294] dump_stack+0x1b2/0x281 [ 27.195894] ? ovl_workdir_create.cold+0xeb/0xf7 [ 27.200621] lock_release.cold+0x70/0xbf [ 27.204654] ? lock_downgrade+0x740/0x740 [ 27.208773] ovl_workdir_create.cold+0xeb/0xf7 [ 27.213326] ? clone_private_mount+0x24f/0x2f0 [ 27.217879] ? ovl_mount_dir+0x190/0x190 [ 27.221924] ? lock_downgrade+0x740/0x740 [ 27.226043] ? up_read+0x17/0x30 [ 27.229379] ? clone_private_mount+0x113/0x2f0 [ 27.233940] ovl_fill_super+0xfe9/0x2610 [ 27.237988] ? ovl_put_super+0x4a0/0x4a0 [ 27.242031] ? sget_userns+0x768/0xc10 [ 27.245894] ? get_anon_bdev+0x1c0/0x1c0 [ 27.249929] ? sget+0xd9/0x110 [ 27.253091] ? ovl_put_super+0x4a0/0x4a0 [ 27.257124] mount_nodev+0x4c/0xf0 [ 27.260721] mount_fs+0x92/0x2a0 [ 27.264060] vfs_kern_mount.part.0+0x5b/0x470 [ 27.268527] do_mount+0xe65/0x2a10 [ 27.272045] ? do_raw_spin_unlock+0x164/0x220 [ 27.276509] ? copy_mount_string+0x40/0x40 [ 27.280719] ? rcu_read_lock_sched_held+0x16c/0x1d0 [ 27.285702] ? copy_mnt_ns+0xa30/0xa30 [ 27.289562] ? copy_mount_options+0x1fa/0x2f0 [ 27.294027] ? copy_mnt_ns+0xa30/0xa30 [ 27.297886] SyS_mount+0xa8/0x120 [ 27.301312] ? copy_mnt_ns+0xa30/0xa30 [ 27.305168] do_syscall_64+0x1d5/0x640 [ 27.309028] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 27.314189] RIP: 0033:0x7f3488b390e9 [ 27.317869] RSP: 002b:00007fff2f0687d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 27.325547] RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007f3488b390e9 [ 27.332798] RDX: 0000000020000080 RSI: 0000000020000040 RDI: 0000000000000000 [ 27.340038] RBP: 00007f3488afd0d0 R08: 0000000020000340 R09: 0000000000000000 [ 27.347290] R10: 0000000000000000 R11