[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 20.552793] random: sshd: uninitialized urandom read (32 bytes read, 31 bits of entropy available) [?25l[?1c7[ ok 8[?25h[?0c. [ 21.055087] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [ 21.317448] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.444078] random: sshd: uninitialized urandom read (32 bytes read, 115 bits of entropy available) [ 37.254429] random: sshd: uninitialized urandom read (32 bytes read, 123 bits of entropy available) Warning: Permanently added '10.128.0.58' (ECDSA) to the list of known hosts. [ 42.827439] random: sshd: uninitialized urandom read (32 bytes read, 127 bits of entropy available) 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 executing program executing program [ 42.919460] page:ffffea0002dc0000 count:2 mapcount:0 mapping: (null) index:0x0 [ 42.934301] flags: 0x4000000000004004(referenced|head) [ 42.940179] page dumped because: VM_BUG_ON_PAGE(!PageLocked(page)) [ 42.947333] ------------[ cut here ]------------ [ 42.952066] kernel BUG at mm/filemap.c:819! [ 42.956367] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 42.962182] Dumping ftrace buffer: [ 42.965694] (ftrace buffer empty) [ 42.969377] Modules linked in: [ 42.972662] CPU: 0 PID: 3755 Comm: syz-executor634 Not tainted 4.4.131-g033c952 #36 [ 42.980428] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.989759] task: ffff8801ccfe1800 task.stack: ffff8801ccbd8000 [ 42.995788] RIP: 0010:[] [] unlock_page+0x115/0x150 [ 43.004134] RSP: 0018:ffff8801ccbdf760 EFLAGS: 00010293 [ 43.009563] RAX: ffffffff83a6e7c0 RBX: ffffea0002dc0000 RCX: 0000000000000000 [ 43.016809] RDX: 0000000000000000 RSI: ffffffff81513249 RDI: ffff8801ccfe20dc [ 43.024053] RBP: ffff8801ccbdf780 R08: 0000000000000001 R09: 0000000000000000 [ 43.031301] R10: 0000000000000001 R11: 0000000000000001 R12: dffffc0000000000 [ 43.038541] R13: ffff8801ccbdfa30 R14: ffffea0002dc1480 R15: ffffea0002dc0008 [ 43.045794] FS: 0000000000000000(0000) GS:ffff8801db200000(0063) knlGS:00000000f7700b40 [ 43.053997] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 43.059851] CR2: 00000000204a4ff0 CR3: 00000001d113e000 CR4: 00000000001606f0 [ 43.067095] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 43.074341] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 43.081591] Stack: [ 43.083710] ffffea0002dc0000 dffffc0000000000 ffff8801ccbdfa30 ffffea0002dc1480 [ 43.091684] ffff8801ccbdf868 ffffffff812cc1bc 0000000000000001 ffff8801ccbdf818 [ 43.099678] 0000000000000046 ffff8800b00d8a00 00000000ccfe20d8 ffff8801ccbdfa40 [ 43.107650] Call Trace: [ 43.110218] [] get_futex_key+0xadc/0xd80 [ 43.115908] [] ? futex_lock_pi_atomic+0x2b0/0x2b0 [ 43.123275] [] ? _raw_spin_unlock_irqrestore+0x45/0x70 [ 43.130172] [] futex_wait_setup+0xd9/0x330 [ 43.136027] [] ? futex_wake+0x460/0x460 [ 43.141632] [] ? __hrtimer_init+0x143/0x1e0 [ 43.147581] [] futex_wait+0x2af/0x600 [ 43.153001] [] ? futex_wait_setup+0x330/0x330 [ 43.159120] [] ? native_set_pte_at+0xe0/0xe0 [ 43.165154] [] ? do_huge_pmd_anonymous_page+0x52d/0x9d0 [ 43.172136] [] ? clock_was_set_work+0x30/0x30 [ 43.178252] [] do_futex+0x2a2/0x1770 [ 43.183585] [] ? exit_robust_list+0x220/0x220 [ 43.189704] [] ? retint_kernel+0x2d/0x2d [ 43.195388] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 43.202378] [] ? ktime_add_safe+0xea/0x150 [ 43.208233] [] ? SyS_alarm+0x20/0x20 [ 43.213577] [] ? kvm_clock_read+0x23/0x40 [ 43.219347] [] ? kvm_clock_get_cycles+0x9/0x10 [ 43.225567] [] ? compat_SyS_futex+0x26d/0x2f0 [ 43.231686] [] compat_SyS_futex+0x1d9/0x2f0 [ 43.237629] [] ? compat_SyS_get_robust_list+0x310/0x310 [ 43.244699] [] ? __bad_area_nosemaphore+0x21e/0x310 [ 43.251337] [] ? do_fast_syscall_32+0xdb/0x8b0 [ 43.257540] [] ? compat_SyS_get_robust_list+0x310/0x310 [ 43.264524] [] do_fast_syscall_32+0x326/0x8b0 [ 43.270640] [] sysenter_flags_fixed+0xd/0x17 [ 43.276665] 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 [ 43.303442] RIP [] unlock_page+0x115/0x150 [ 43.309425] RSP [ 43.313171] ---[ end trace 0cceca91238a96d8 ]--- executing program [ 43.318061] Kernel panic - not syncing: Fatal exception [ 43.323873] Dumping ftrace buffer: [ 43.327385] (ftrace buffer empty) [ 43.331078] Kernel Offset: disabled [ 43.334686] Rebooting in 86400 seconds..