[....] 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[ 14.120985] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 16.288320] random: sshd: uninitialized urandom read (32 bytes read) [ 16.594033] random: sshd: uninitialized urandom read (32 bytes read) [ 17.110586] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.37' (ECDSA) to the list of known hosts. [ 22.851001] urandom_read: 1 callbacks suppressed [ 22.851005] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 22.945970] BUG: unable to handle kernel paging request at ffffeafff90e8020 [ 22.953309] IP: [] page_remove_rmap+0x37/0x6d0 [ 22.959610] PGD 0 [ 22.961561] [ 22.963181] Oops: 0000 [#1] PREEMPT SMP KASAN [ 22.967654] Dumping ftrace buffer: [ 22.971258] (ftrace buffer empty) [ 22.974944] Modules linked in: [ 22.978248] CPU: 1 PID: 3790 Comm: syz-executor274 Not tainted 4.9.122-g54068d6 #26 [ 22.986045] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 22.995406] task: ffff8801b68e8000 task.stack: ffff8801b6020000 [ 23.001474] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 23.010153] RSP: 0018:ffff8801b6027948 EFLAGS: 00010246 [ 23.015580] RAX: dffffc0000000000 RBX: ffffeafff90e8000 RCX: 0000000000000000 [ 23.022839] RDX: 1ffffd5fff21d004 RSI: ffffffff814f5918 RDI: ffffeafff90e8000 [ 23.030086] RBP: ffff8801b6027970 R08: 0000000000033500 R09: 0000000000000001 [ 23.037356] R10: ffff8801b68e8000 R11: 0000000000000001 R12: ffff8801b6027c08 [ 23.044632] R13: ffffeafff90e8020 R14: ffffeafff90e8000 R15: 0000000000000001 [ 23.051891] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 23.060106] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 23.065989] CR2: ffffeafff90e8020 CR3: 00000001cb18c000 CR4: 00000000001606f0 [ 23.073274] Stack: [ 23.075402] ffffeafff90e8020 ffff8801b6027c08 ffff8801bd823800 ffffeafff90e8000 [ 23.083423] ffff8801b694be18 ffff8801b60279c8 ffffffff8154cb8f ffff8801b6027c18 [ 23.091456] ffff8801b6027c10 ffff8801b6027c88 00003ffe43a001e0 00000001bd823000 [ 23.099487] Call Trace: [ 23.102052] [] zap_huge_pmd+0x16f/0x860 [ 23.107686] [] unmap_page_range+0x12ad/0x1730 [ 23.113827] [] ? vm_normal_page_pmd+0x310/0x310 [ 23.120124] [] unmap_single_vma+0x101/0x260 [ 23.126096] [] unmap_vmas+0x102/0x1d0 [ 23.131545] [] exit_mmap+0x214/0x3f0 [ 23.136890] [] ? SyS_munmap+0xa0/0xa0 [ 23.142321] [] ? up_write+0x1a/0x60 [ 23.147579] [] mmput+0xf3/0x2d0 [ 23.152486] [] do_exit+0x906/0x27b0 [ 23.157741] [] ? release_task.part.19+0x1210/0x1210 [ 23.164380] [] ? up_write+0x1a/0x60 [ 23.169656] [] ? do_mprotect_pkey+0x71d/0x890 [ 23.175785] [] ? mprotect_fixup+0x930/0x930 [ 23.181747] [] do_group_exit+0x111/0x340 [ 23.187432] [] ? do_group_exit+0x340/0x340 [ 23.193303] [] SyS_exit_group+0x1d/0x20 [ 23.198905] [] do_syscall_64+0x1a6/0x490 [ 23.204595] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 23.211492] Code: 55 41 54 53 48 89 fb e8 58 b4 e6 ff 4c 8d 6b 20 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 b8 05 00 00 <4c> 8b 73 20 49 89 dc 41 f6 c6 01 0f 85 4b 03 00 00 e8 23 b4 e6 [ 23.238577] RIP [] page_remove_rmap+0x37/0x6d0 [ 23.244935] RSP [ 23.248551] CR2: ffffeafff90e8020 [ 23.251981] ---[ end trace ede9d619e62ce188 ]--- [ 23.256728] Kernel panic - not syncing: Fatal exception [ 23.262405] Dumping ftrace buffer: [ 23.265934] (ftrace buffer empty) [ 23.269622] Kernel Offset: disabled [ 23.273227] Rebooting in 86400 seconds..