[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 20.801613] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 24.402378] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 24.698053] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 25.762856] random: sshd: uninitialized urandom read (32 bytes read, 122 bits of entropy available) [ 33.893012] random: nonblocking pool is initialized Warning: Permanently added '10.128.0.47' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 39.553528] page:ffffea0002dc0000 count:2 mapcount:0 mapping: (null) index:0x0 [ 39.561900] flags: 0x4000000000004004(referenced|head) [ 39.567660] page dumped because: VM_BUG_ON_PAGE(!PageLocked(page)) [ 39.574007] ------------[ cut here ]------------ [ 39.578731] kernel BUG at mm/filemap.c:819! [ 39.583022] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 39.588856] Dumping ftrace buffer: [ 39.592367] (ftrace buffer empty) [ 39.596048] Modules linked in: [ 39.599331] CPU: 0 PID: 3787 Comm: syz-executor503 Not tainted 4.4.128-gbd23e3a #20 [ 39.607093] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 39.616416] task: ffff8800af459800 task.stack: ffff8800afa78000 [ 39.622441] RIP: 0010:[] [] unlock_page+0x115/0x150 [ 39.630769] RSP: 0018:ffff8800afa7f7d8 EFLAGS: 00010293 [ 39.636188] RAX: ffffffff83a6e7c0 RBX: ffffea0002dc0000 RCX: 0000000000000000 [ 39.643431] RDX: 0000000000000000 RSI: ffffffff815130e9 RDI: ffff8800af45a0dc [ 39.650670] RBP: ffff8800afa7f7f8 R08: 0000000000000001 R09: 0000000000000000 [ 39.657912] R10: 0000000000000001 R11: 0000000000000001 R12: dffffc0000000000 [ 39.665153] R13: ffff8800afa7faa8 R14: ffffea0002dc1480 R15: ffffea0002dc0008 [ 39.672396] FS: 00007f29a9e00700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 39.680593] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 39.686444] CR2: 00000000204a4ff0 CR3: 00000000b5b54000 CR4: 0000000000160670 [ 39.693688] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 39.700929] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 39.708171] Stack: [ 39.710292] ffffea0002dc0000 dffffc0000000000 ffff8800afa7faa8 ffffea0002dc1480 [ 39.718271] ffff8800afa7f8e0 ffffffff812cc19c 0000000000000001 ffff8800afa7f890 [ 39.726253] 0000000000000046 ffff8801cadfa300 00000000af45a0d8 ffff8800afa7fab8 [ 39.734224] Call Trace: [ 39.736786] [] get_futex_key+0xadc/0xd80 [ 39.742471] [] ? futex_lock_pi_atomic+0x2b0/0x2b0 [ 39.749053] [] ? _raw_spin_unlock_irqrestore+0x45/0x70 [ 39.755951] [] futex_wait_setup+0xd9/0x330 [ 39.761810] [] ? futex_wake+0x460/0x460 [ 39.767404] [] ? __hrtimer_init+0x143/0x1e0 [ 39.773345] [] futex_wait+0x2af/0x600 [ 39.778766] [] ? futex_wait_setup+0x330/0x330 [ 39.784880] [] ? clock_was_set_work+0x30/0x30 [ 39.790993] [] do_futex+0x2a2/0x1770 [ 39.796326] [] ? exit_robust_list+0x220/0x220 [ 39.802439] [] ? __do_page_fault+0x385/0xa10 [ 39.808472] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 39.815280] [] ? ktime_add_safe+0xea/0x150 [ 39.821135] [] ? SyS_alarm+0x20/0x20 [ 39.826467] [] ? kvm_clock_read+0x23/0x40 [ 39.832233] [] ? kvm_clock_get_cycles+0x9/0x10 [ 39.838434] [] ? SyS_futex+0x284/0x300 [ 39.843942] [] SyS_futex+0x1f0/0x300 [ 39.849450] [] ? do_futex+0x1770/0x1770 [ 39.855044] [] ? retint_user+0x18/0x3c [ 39.860553] [] ? trace_hardirqs_on_thunk+0x17/0x19 [ 39.867112] [] entry_SYSCALL_64_fastpath+0x22/0x9e [ 39.873656] Code: e8 48 8d 04 c0 49 8d 3c c6 e8 f8 be df ff 5b 41 5c 41 5d 41 5e 5d c3 e8 8a 32 f3 ff 48 c7 c6 60 aa a9 83 48 89 df e8 4b eb 06 00 <0f> 0b 48 89 df e8 61 af 0d 00 e9 0a ff ff ff e8 57 af 0d 00 e9 [ 39.900311] RIP [] unlock_page+0x115/0x150 [ 39.906287] RSP [ 39.910656] ---[ end trace 042407b477784937 ]--- [ 39.915699] Kernel panic - not syncing: Fatal exception [ 39.921380] Dumping ftrace buffer: [ 39.924890] (ftrace buffer empty) [ 39.928571] Kernel Offset: disabled [ 39.932168] Rebooting in 86400 seconds..