[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.486306] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. [ 20.447285] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.838368] random: sshd: uninitialized urandom read (32 bytes read) [ 21.677117] random: sshd: uninitialized urandom read (32 bytes read) [ 21.839458] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.47' (ECDSA) to the list of known hosts. [ 27.279904] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program executing program [ 27.377633] BTRFS: device fsid ecf6f2a2-2997-48ae-b81e-1b00920efd9a devid 0 transid 210 /dev/loop0 [ 27.393656] WARNING: CPU: 1 PID: 4549 at fs/btrfs/volumes.c:1071 close_fs_devices+0xbc7/0xfa0 [ 27.402355] Kernel panic - not syncing: panic_on_warn set ... [ 27.402355] [ 27.409729] CPU: 1 PID: 4549 Comm: syz-executor207 Not tainted 4.17.0+ #94 [ 27.416739] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.426095] Call Trace: [ 27.428677] dump_stack+0x1b9/0x294 [ 27.432309] ? dump_stack_print_info.cold.2+0x52/0x52 [ 27.437519] ? close_fs_devices+0xad0/0xfa0 [ 27.441860] panic+0x22f/0x4de [ 27.445063] ? add_taint.cold.5+0x16/0x16 [ 27.449227] ? __warn.cold.8+0x148/0x1b3 [ 27.453294] ? __warn.cold.8+0x117/0x1b3 [ 27.457359] ? close_fs_devices+0xbc7/0xfa0 [ 27.461692] __warn.cold.8+0x163/0x1b3 [ 27.465587] ? close_fs_devices+0xbc7/0xfa0 [ 27.469918] report_bug+0x252/0x2d0 [ 27.473560] do_error_trap+0x1fc/0x4d0 [ 27.477461] ? trace_hardirqs_on+0xd/0x10 [ 27.481615] ? math_error+0x3f0/0x3f0 [ 27.485423] ? note_gp_changes+0x540/0x540 [ 27.489672] ? __blkdev_put+0x3f1/0x830 [ 27.493660] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.498513] do_invalid_op+0x1b/0x20 [ 27.502235] invalid_op+0x14/0x20 [ 27.505693] RIP: 0010:close_fs_devices+0xbc7/0xfa0 [ 27.510610] Code: 1b b3 fe 0f 0b e8 89 1b b3 fe 0f 0b 48 89 f7 e8 df 0e f0 fe e9 f6 f5 ff ff e8 75 1b b3 fe 0f 0b e9 fd fd ff ff e8 69 1b b3 fe <0f> 0b e9 a8 fd ff ff 48 8b bd 58 fd ff ff e8 76 0f f0 fe e9 35 fd [ 27.529947] RSP: 0000:ffff8801d649f050 EFLAGS: 00010293 [ 27.535312] RAX: ffff8801ac070000 RBX: 0000000000000001 RCX: ffffffff82c71f9d [ 27.542568] RDX: 0000000000000000 RSI: ffffffff82c721f7 RDI: 0000000000000007 [ 27.549819] RBP: ffff8801d649f350 R08: ffff8801ac070000 R09: 0000000000000006 [ 27.557077] R10: ffff8801ac070000 R11: 0000000000000000 R12: ffffed003ac93e25 [ 27.564335] R13: 1ffff1003ac93e5d R14: ffff8801d649f2e8 R15: ffff8801ac6f96c8 [ 27.571603] ? close_fs_devices+0x96d/0xfa0 [ 27.575904] ? close_fs_devices+0xbc7/0xfa0 [ 27.580209] ? btrfs_alloc_device+0x8b0/0x8b0 [ 27.584684] ? kasan_check_read+0x11/0x20 [ 27.588812] ? do_raw_spin_unlock+0x9e/0x2e0 [ 27.593202] ? kasan_check_write+0x14/0x20 [ 27.597417] ? wake_up_q+0xb3/0x100 [ 27.601040] ? __mutex_unlock_slowpath+0x422/0x8a0 [ 27.605951] ? wait_for_completion+0x870/0x870 [ 27.610526] btrfs_close_devices+0x29/0x150 [ 27.614829] btrfs_mount_root+0x1419/0x1e70 [ 27.619140] ? btrfs_decode_error+0x70/0x70 [ 27.623450] ? save_stack+0x43/0xd0 [ 27.627061] ? __kasan_slab_free+0x11a/0x170 [ 27.631452] ? kasan_slab_free+0xe/0x10 [ 27.635404] ? kfree+0xd9/0x260 [ 27.638665] ? mount_fs+0xae/0x328 [ 27.642195] ? vfs_kern_mount.part.34+0xd4/0x4d0 [ 27.646927] ? do_mount+0x564/0x30b0 [ 27.650619] ? ksys_mount+0x12d/0x140 [ 27.654404] ? __x64_sys_mount+0xbe/0x150 [ 27.658537] ? do_syscall_64+0x1b1/0x800 [ 27.662582] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 27.667926] ? kasan_check_read+0x11/0x20 [ 27.672062] ? do_raw_spin_unlock+0x9e/0x2e0 [ 27.676454] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 27.681028] ? kasan_check_write+0x14/0x20 [ 27.685250] ? do_raw_spin_lock+0xc1/0x200 [ 27.689468] mount_fs+0xae/0x328 [ 27.692819] ? debug_check_no_obj_freed+0x2ff/0x584 [ 27.697820] vfs_kern_mount.part.34+0xd4/0x4d0 [ 27.702395] ? may_umount+0xb0/0xb0 [ 27.706003] ? quarantine_put+0xeb/0x190 [ 27.710055] ? kfree+0x111/0x260 [ 27.713405] ? btrfs_mount+0x831/0x213e [ 27.717368] vfs_kern_mount+0x40/0x60 [ 27.721153] btrfs_mount+0x4a1/0x213e [ 27.724935] ? kasan_check_read+0x11/0x20 [ 27.729074] ? rcu_is_watching+0x85/0x140 [ 27.733205] ? btrfs_remount+0x16f0/0x16f0 [ 27.737421] ? __lockdep_init_map+0x105/0x590 [ 27.741899] ? __lockdep_init_map+0x105/0x590 [ 27.746378] ? lockdep_init_map+0x9/0x10 [ 27.750418] ? __init_waitqueue_head+0x96/0x140 [ 27.755066] ? init_wait_entry+0x1b0/0x1b0 [ 27.759280] ? memcpy+0x45/0x50 [ 27.762557] ? alloc_vfsmnt+0x771/0x9d0 [ 27.766510] ? mnt_free_id.isra.27+0x60/0x60 [ 27.770907] ? kasan_check_read+0x11/0x20 [ 27.775043] ? graph_lock+0x170/0x170 [ 27.778824] ? rcu_pm_notify+0xc0/0xc0 [ 27.782691] ? trace_hardirqs_off+0xd/0x10 [ 27.786909] ? putname+0xf2/0x130 [ 27.790347] ? find_held_lock+0x36/0x1c0 [ 27.794392] ? lock_downgrade+0x8e0/0x8e0 [ 27.798529] ? module_unload_free+0x5b0/0x5b0 [ 27.803012] mount_fs+0xae/0x328 [ 27.806370] ? btrfs_remount+0x16f0/0x16f0 [ 27.810584] ? mount_fs+0xae/0x328 [ 27.814104] ? mpi_free.cold.1+0x19/0x19 [ 27.818145] vfs_kern_mount.part.34+0xd4/0x4d0 [ 27.822722] ? may_umount+0xb0/0xb0 [ 27.826331] ? _raw_read_unlock+0x22/0x30 [ 27.830459] ? __get_fs_type+0x97/0xc0 [ 27.834327] do_mount+0x564/0x30b0 [ 27.837848] ? do_raw_spin_unlock+0x9e/0x2e0 [ 27.842234] ? copy_mount_string+0x40/0x40 [ 27.846455] ? rcu_pm_notify+0xc0/0xc0 [ 27.850325] ? copy_mount_options+0x5f/0x380 [ 27.854714] ? rcu_read_lock_sched_held+0x108/0x120 [ 27.859709] ? kmem_cache_alloc_trace+0x616/0x780 [ 27.864534] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 27.870053] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 27.875573] ? copy_mount_options+0x285/0x380 [ 27.880062] ksys_mount+0x12d/0x140 [ 27.883674] __x64_sys_mount+0xbe/0x150 [ 27.887631] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 27.892635] do_syscall_64+0x1b1/0x800 [ 27.896502] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 27.901327] ? syscall_return_slowpath+0x5c0/0x5c0 [ 27.906248] ? syscall_return_slowpath+0x30f/0x5c0 [ 27.911176] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 27.916536] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.921364] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 27.926549] RIP: 0033:0x44320a [ 27.929717] Code: b8 08 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 fd e5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 da e5 fb ff c3 66 0f 1f 84 00 00 00 00 00 [ 27.948881] RSP: 002b:00007ffdfa1a39f8 EFLAGS: 00000297 ORIG_RAX: 00000000000000a5 [ 27.956570] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000044320a [ 27.963820] RDX: 0000000020000080 RSI: 0000000020000100 RDI: 00007ffdfa1a3a10 [ 27.971075] RBP: 0000000000000004 R08: 0000000020000240 R09: 000000000000000a [ 27.978323] R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000401c70 [ 27.985572] R13: 0000000008100000 R14: fe30656c69662f2e R15: fe03f80fe03f80ff [ 27.993425] Dumping ftrace buffer: [ 27.997068] (ftrace buffer empty) [ 28.000757] Kernel Offset: disabled [ 28.004364] Rebooting in 86400 seconds..