[....] 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[ 35.686455] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 40.643758] random: sshd: uninitialized urandom read (32 bytes read) [ 40.928657] random: sshd: uninitialized urandom read (32 bytes read) [ 41.439568] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.48' (ECDSA) to the list of known hosts. [ 47.034308] urandom_read: 1 callbacks suppressed [ 47.034311] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 47.119845] BUG: unable to handle kernel paging request at ffffeafff8e28020 [ 47.127289] IP: [] page_remove_rmap+0x37/0x6d0 [ 47.133593] PGD 0 [ 47.135547] [ 47.137173] Oops: 0000 [#1] PREEMPT SMP KASAN [ 47.141647] Dumping ftrace buffer: [ 47.145161] (ftrace buffer empty) [ 47.148846] Modules linked in: [ 47.152141] CPU: 0 PID: 3808 Comm: syz-executor135 Not tainted 4.9.122-g54068d6 #78 [ 47.159909] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.169240] task: ffff8801b7351800 task.stack: ffff8801b5cf8000 [ 47.175269] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 47.183966] RSP: 0018:ffff8801b5cff948 EFLAGS: 00010246 [ 47.189402] RAX: dffffc0000000000 RBX: ffffeafff8e28000 RCX: 0000000000000000 [ 47.196647] RDX: 1ffffd5fff1c5004 RSI: ffffffff814f5918 RDI: ffffeafff8e28000 [ 47.203893] RBP: ffff8801b5cff970 R08: 0000000000034920 R09: 0000000000000001 [ 47.211160] R10: ffff8801b7351800 R11: 0000000000000001 R12: ffff8801b5cffc08 [ 47.218408] R13: ffffeafff8e28020 R14: ffffeafff8e28000 R15: 0000000000000001 [ 47.225659] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 47.233862] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 47.239720] CR2: ffffeafff8e28020 CR3: 00000001c7b79000 CR4: 00000000001606f0 [ 47.246967] Stack: [ 47.249094] ffffeafff8e28020 ffff8801b5cffc08 ffff8801c521e800 ffffeafff8e28000 [ 47.257182] ffff8801c46bcdc0 ffff8801b5cff9c8 ffffffff8154cb8f ffff8801b5cffc18 [ 47.265169] ffff8801b5cffc10 ffff8801b5cffc88 00003ffe38a001e0 00000001c521e000 [ 47.273205] Call Trace: [ 47.275819] [] zap_huge_pmd+0x16f/0x860 [ 47.281430] [] unmap_page_range+0x12ad/0x1730 [ 47.287655] [] ? vm_normal_page_pmd+0x310/0x310 [ 47.293956] [] unmap_single_vma+0x101/0x260 [ 47.299905] [] unmap_vmas+0x102/0x1d0 [ 47.305327] [] exit_mmap+0x214/0x3f0 [ 47.310668] [] ? SyS_munmap+0xa0/0xa0 [ 47.316095] [] ? up_write+0x1a/0x60 [ 47.321347] [] mmput+0xf3/0x2d0 [ 47.326249] [] do_exit+0x906/0x27b0 [ 47.331617] [] ? release_task.part.19+0x1210/0x1210 [ 47.338360] [] ? up_write+0x1a/0x60 [ 47.343611] [] ? do_mprotect_pkey+0x71d/0x890 [ 47.349741] [] ? mprotect_fixup+0x930/0x930 [ 47.355709] [] do_group_exit+0x111/0x340 [ 47.361406] [] ? do_group_exit+0x340/0x340 [ 47.367317] [] SyS_exit_group+0x1d/0x20 [ 47.372933] [] do_syscall_64+0x1a6/0x490 [ 47.378631] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 47.385527] 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 [ 47.412530] RIP [] page_remove_rmap+0x37/0x6d0 [ 47.418851] RSP [ 47.422447] CR2: ffffeafff8e28020 [ 47.425874] ---[ end trace c210460780bed261 ]--- [ 47.430638] Kernel panic - not syncing: Fatal exception [ 47.436241] Dumping ftrace buffer: [ 47.439774] (ftrace buffer empty) [ 47.443458] Kernel Offset: disabled [ 47.447073] Rebooting in 86400 seconds..