[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 20.235742] 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: [ 23.781013] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 24.176530] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 25.219541] random: nonblocking pool is initialized Warning: Permanently added '10.128.10.44' (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 executing program executing program executing program executing program [ 31.128042] page:ffffea0007278000 count:2 mapcount:0 mapping: (null) index:0x0 [ 31.140597] flags: 0x8000000000004004(referenced|head) [ 31.146276] page dumped because: VM_BUG_ON_PAGE(!PageLocked(page)) [ 31.154162] ------------[ cut here ]------------ [ 31.158907] kernel BUG at mm/filemap.c:819! [ 31.163199] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 31.169005] Dumping ftrace buffer: [ 31.172519] (ftrace buffer empty) [ 31.176226] Modules linked in: [ 31.179509] CPU: 0 PID: 3790 Comm: syz-executor404 Not tainted 4.4.131-g6ec0e3f #35 [ 31.187273] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.196598] task: ffff8800af973000 task.stack: ffff8800af1e0000 [ 31.202627] RIP: 0010:[] [] unlock_page+0x115/0x150 [ 31.210955] RSP: 0018:ffff8800af1e77d8 EFLAGS: 00010293 [ 31.216376] RAX: ffffffff83a6e7c0 RBX: ffffea0007278000 RCX: 0000000000000000 [ 31.223617] RDX: 0000000000000000 RSI: ffffffff81513249 RDI: ffff8800af9738dc [ 31.230858] RBP: ffff8800af1e77f8 R08: 0000000000000001 R09: 0000000000000000 [ 31.238098] R10: 0000000000000001 R11: 0000000000000001 R12: dffffc0000000000 [ 31.245342] R13: ffff8800af1e7aa8 R14: ffffea0007279480 R15: ffffea0007278008 [ 31.252584] FS: 00007fb96f555700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 31.260783] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 31.266635] CR2: 00007fb96f533db8 CR3: 00000000b6ed5000 CR4: 00000000001606f0 [ 31.273879] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 31.281123] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 31.288364] Stack: [ 31.290484] ffffea0007278000 dffffc0000000000 ffff8800af1e7aa8 ffffea0007279480 [ 31.298467] ffff8800af1e78e0 ffffffff812cc1bc 0000000000000001 ffff8800af1e7890 [ 31.306443] 0000000000000046 ffff8800af8d1900 00000000af9738d8 ffff8800af1e7ab8 [ 31.314419] Call Trace: [ 31.317342] [] get_futex_key+0xadc/0xd80 [ 31.323023] [] ? futex_lock_pi_atomic+0x2b0/0x2b0 [ 31.329489] [] ? _raw_spin_unlock_irqrestore+0x45/0x70 [ 31.336387] [] futex_wait_setup+0xd9/0x330 [ 31.342244] [] ? futex_wake+0x460/0x460 [ 31.347839] [] ? __hrtimer_init+0x143/0x1e0 [ 31.353783] [] futex_wait+0x2af/0x600 [ 31.359205] [] ? futex_wait_setup+0x330/0x330 [ 31.365322] [] ? clock_was_set_work+0x30/0x30 [ 31.371439] [] do_futex+0x2a2/0x1770 [ 31.376772] [] ? exit_robust_list+0x220/0x220 [ 31.382888] [] ? __do_page_fault+0x385/0xa10 [ 31.388919] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 31.396031] [] ? ktime_add_safe+0xea/0x150 [ 31.401887] [] ? SyS_alarm+0x20/0x20 [ 31.407222] [] ? kvm_clock_read+0x23/0x40 [ 31.412989] [] ? kvm_clock_get_cycles+0x9/0x10 [ 31.419192] [] ? SyS_futex+0x284/0x300 [ 31.424703] [] SyS_futex+0x1f0/0x300 [ 31.430038] [] ? do_futex+0x1770/0x1770 [ 31.435636] [] ? retint_user+0x18/0x3c [ 31.441146] [] ? trace_hardirqs_on_thunk+0x17/0x19 [ 31.447695] [] entry_SYSCALL_64_fastpath+0x22/0x9e [ 31.454244] Code: e8 48 8d 04 c0 49 8d 3c c6 e8 48 c0 df ff 5b 41 5c 41 5d 41 5e 5d c3 e8 da 33 f3 ff 48 c7 c6 60 aa a9 83 48 89 df e8 4b eb 06 00 <0f> 0b 48 89 df e8 f1 b1 0d 00 e9 0a ff ff ff e8 e7 b1 0d 00 e9 [ 31.481026] RIP [] unlock_page+0x115/0x150 [ 31.487000] RSP [ 31.490859] ---[ end trace 665ee9397f60905a ]--- [ 31.496256] Kernel panic - not syncing: Fatal exception [ 31.502080] Dumping ftrace buffer: [ 31.505590] (ftrace buffer empty) [ 31.509271] Kernel Offset: disabled [ 31.512865] Rebooting in 86400 seconds..