[....] 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[ 16.138123] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 26.755543] random: sshd: uninitialized urandom read (32 bytes read) [ 27.067570] random: sshd: uninitialized urandom read (32 bytes read) [ 27.539510] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.57' (ECDSA) to the list of known hosts. [ 33.192335] urandom_read: 1 callbacks suppressed [ 33.192338] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 33.278682] BUG: unable to handle kernel paging request at ffffeafff9110020 [ 33.286129] IP: [] page_remove_rmap+0x37/0x6d0 [ 33.292374] PGD 0 [ 33.294320] [ 33.295944] Oops: 0000 [#1] PREEMPT SMP KASAN [ 33.300417] Dumping ftrace buffer: [ 33.304044] (ftrace buffer empty) [ 33.307735] Modules linked in: [ 33.311094] CPU: 0 PID: 3795 Comm: syz-executor038 Not tainted 4.9.122-g54068d6 #78 [ 33.318863] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.328201] task: ffff8801b76f8000 task.stack: ffff8801d9518000 [ 33.334234] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 33.342916] RSP: 0018:ffff8801d951f948 EFLAGS: 00010246 [ 33.348527] RAX: dffffc0000000000 RBX: ffffeafff9110000 RCX: 0000000000000000 [ 33.355817] RDX: 1ffffd5fff222004 RSI: ffffffff814f5918 RDI: ffffeafff9110000 [ 33.363082] RBP: ffff8801d951f970 R08: 0000000000034ac0 R09: 0000000000000001 [ 33.370431] R10: ffff8801b76f8000 R11: 0000000000000001 R12: ffff8801d951fc08 [ 33.377688] R13: ffffeafff9110020 R14: ffffeafff9110000 R15: 0000000000000001 [ 33.384941] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 33.393147] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 33.399006] CR2: ffffeafff9110020 CR3: 00000001bbcff000 CR4: 00000000001606f0 [ 33.406257] Stack: [ 33.408388] ffffeafff9110020 ffff8801d951fc08 ffff8801c7f63800 ffffeafff9110000 [ 33.416402] ffff8801c4fa0898 ffff8801d951f9c8 ffffffff8154cb8f ffff8801d951fc18 [ 33.424438] ffff8801d951fc10 ffff8801d951fc88 00003ffe444001e0 00000001c7f63000 [ 33.432458] Call Trace: [ 33.435033] [] zap_huge_pmd+0x16f/0x860 [ 33.440635] [] unmap_page_range+0x12ad/0x1730 [ 33.446800] [] ? vm_normal_page_pmd+0x310/0x310 [ 33.453103] [] unmap_single_vma+0x101/0x260 [ 33.459152] [] unmap_vmas+0x102/0x1d0 [ 33.464607] [] exit_mmap+0x214/0x3f0 [ 33.469994] [] ? SyS_munmap+0xa0/0xa0 [ 33.475531] [] ? up_write+0x1a/0x60 [ 33.480790] [] mmput+0xf3/0x2d0 [ 33.485704] [] do_exit+0x906/0x27b0 [ 33.490967] [] ? release_task.part.19+0x1210/0x1210 [ 33.497724] [] ? up_write+0x1a/0x60 [ 33.502984] [] ? do_mprotect_pkey+0x71d/0x890 [ 33.509114] [] ? mprotect_fixup+0x930/0x930 [ 33.515076] [] do_group_exit+0x111/0x340 [ 33.520821] [] ? do_group_exit+0x340/0x340 [ 33.526692] [] SyS_exit_group+0x1d/0x20 [ 33.532299] [] do_syscall_64+0x1a6/0x490 [ 33.537989] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 33.544889] 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 [ 33.572585] RIP [] page_remove_rmap+0x37/0x6d0 [ 33.578981] RSP [ 33.582622] CR2: ffffeafff9110020 [ 33.586061] ---[ end trace f5cd025e750c5360 ]--- [ 33.590793] Kernel panic - not syncing: Fatal exception [ 33.596393] Dumping ftrace buffer: [ 33.599910] (ftrace buffer empty) [ 33.603602] Kernel Offset: disabled [ 33.607213] Rebooting in 86400 seconds..