[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 21.319127] random: sshd: uninitialized urandom read (32 bytes read, 35 bits of entropy available) [?25l[?1c7[ ok 8[?25h[?0c. [ 21.782049] random: sshd: uninitialized urandom read (32 bytes read, 35 bits of entropy available) [ 22.114387] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.934714] random: sshd: uninitialized urandom read (32 bytes read, 72 bits of entropy available) [ 23.106025] random: sshd: uninitialized urandom read (32 bytes read, 75 bits of entropy available) Warning: Permanently added '10.128.0.22' (ECDSA) to the list of known hosts. [ 28.645525] random: sshd: uninitialized urandom read (32 bytes read, 81 bits of entropy available) executing program [ 28.734965] BUG: unable to handle kernel paging request at ffffeafffd3c0008 [ 28.742351] IP: [] page_remove_rmap+0x2e/0x260 [ 28.748618] PGD 0 [ 28.750881] Oops: 0000 [#1] PREEMPT SMP KASAN [ 28.755879] Dumping ftrace buffer: [ 28.759419] (ftrace buffer empty) [ 28.763108] Modules linked in: [ 28.766416] CPU: 1 PID: 3831 Comm: syz-executor171 Not tainted 4.4.150-g5541782 #19 [ 28.774380] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.783714] task: ffff8800ada93000 task.stack: ffff8800adbb0000 [ 28.789749] RIP: 0010:[] [] page_remove_rmap+0x2e/0x260 [ 28.798445] RSP: 0018:ffff8800adbb7948 EFLAGS: 00010246 [ 28.803881] RAX: dffffc0000000000 RBX: ffffeafffd3c0000 RCX: 0000000000000000 [ 28.811132] RDX: 1ffffd5fffa78001 RSI: ffffffff814bceaf RDI: ffffeafffd3c0008 [ 28.818386] RBP: ffff8800adbb7958 R08: ffffffff85363fb0 R09: 0000000000000000 [ 28.825645] R10: 0000000000000001 R11: ffff8800ada93000 R12: 0000000000000001 [ 28.832921] R13: 1ffff10015b76f2f R14: ffff8800b35e0800 R15: ffffeafffd3c0000 [ 28.840169] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 28.848371] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 28.854227] CR2: ffffeafffd3c0008 CR3: 00000000b35a6000 CR4: 00000000001606f0 [ 28.861480] Stack: [ 28.863602] ffff8800adbb7bd8 0000000000000001 ffff8800adbb7a00 ffffffff8150ad13 [ 28.871721] 00003fff4f0001e0 00003fff4f0001e0 0000000041b58ab3 ffffffff841ef837 [ 28.879745] ffffffff8150ab10 00000000000004f0 ffff8800b45b0948 ffff8800adbb79c8 [ 28.887740] Call Trace: [ 28.890318] [] zap_huge_pmd+0x203/0x510 [ 28.895973] [] ? __pmd_trans_huge_lock+0x320/0x320 [ 28.902527] [] unmap_single_vma+0xea3/0x1240 [ 28.908590] [] ? vm_normal_page+0x280/0x280 [ 28.914539] [] ? __put_single_page+0x60/0x60 [ 28.920575] [] unmap_vmas+0x81/0xd0 [ 28.925827] [] exit_mmap+0x1c9/0x3a0 [ 28.931165] [] ? SyS_remap_file_pages+0x870/0x870 [ 28.937639] [] ? up_write+0x1a/0x60 [ 28.942897] [] mmput+0xf8/0x2d0 [ 28.947813] [] do_exit+0x8d8/0x26b0 [ 28.953066] [] ? handle_mm_fault+0x19b9/0x3180 [ 28.959282] [] ? release_task.part.17+0x1200/0x1200 [ 28.965929] [] do_group_exit+0x111/0x330 [ 28.971617] [] ? do_group_exit+0x330/0x330 [ 28.977491] [] SyS_exit_group+0x1d/0x20 [ 28.983149] [] do_fast_syscall_32+0x324/0x8b0 [ 28.989275] [] sysenter_flags_fixed+0xd/0x1a [ 28.995312] Code: e5 41 54 53 48 89 fb e8 31 76 e9 ff 48 8d 7b 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 de 01 00 00 43 08 01 0f 84 4e 01 00 00 e8 03 76 e9 ff f0 83 43 18 ff 78 [ 29.022415] RIP [] page_remove_rmap+0x2e/0x260 [ 29.028743] RSP [ 29.032342] CR2: ffffeafffd3c0008 [ 29.035779] ---[ end trace d6346a3086c56c7b ]--- [ 29.040510] Kernel panic - not syncing: Fatal exception [ 29.046157] Dumping ftrace buffer: [ 29.049680] (ftrace buffer empty) [ 29.053367] Kernel Offset: disabled [ 29.056972] Rebooting in 86400 seconds..