[....] 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[ 16.424080] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 17.699956] random: sshd: uninitialized urandom read (32 bytes read) [ 17.997629] random: sshd: uninitialized urandom read (32 bytes read) [ 18.505824] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.19' (ECDSA) to the list of known hosts. [ 24.355646] urandom_read: 1 callbacks suppressed [ 24.355649] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 24.445662] BUG: unable to handle kernel paging request at ffffeafff8ef0020 [ 24.453047] IP: [] page_remove_rmap+0x37/0x6d0 [ 24.459318] PGD 0 [ 24.461294] [ 24.462924] Oops: 0000 [#1] PREEMPT SMP KASAN [ 24.467521] Dumping ftrace buffer: [ 24.471214] (ftrace buffer empty) [ 24.474912] Modules linked in: [ 24.478225] CPU: 0 PID: 3793 Comm: syz-executor682 Not tainted 4.9.120-gf85543b #24 [ 24.486005] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.495349] task: ffff8801b62c8000 task.stack: ffff8801d94d0000 [ 24.501516] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 24.510214] RSP: 0018:ffff8801d94d7948 EFLAGS: 00010246 [ 24.515650] RAX: dffffc0000000000 RBX: ffffeafff8ef0000 RCX: 0000000000000000 [ 24.522992] RDX: 1ffffd5fff1de004 RSI: ffffffff814f5128 RDI: ffffeafff8ef0000 [ 24.530330] RBP: ffff8801d94d7970 R08: 0000000000033e40 R09: 0000000000000001 [ 24.537587] R10: ffff8801b62c8000 R11: 0000000000000001 R12: ffff8801d94d7c08 [ 24.544845] R13: ffffeafff8ef0020 R14: ffffeafff8ef0000 R15: 0000000000000001 [ 24.552238] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 24.560473] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 24.566344] CR2: ffffeafff8ef0020 CR3: 00000001ca4cd000 CR4: 00000000001606f0 [ 24.573605] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 24.580861] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 24.588115] Stack: [ 24.590249] ffffeafff8ef0020 ffff8801d94d7c08 ffff8801cb39b800 ffffeafff8ef0000 [ 24.598436] ffff8801c5dc4898 ffff8801d94d79c8 ffffffff8154bfcf ffff8801d94d7c18 [ 24.606485] ffff8801d94d7c10 ffff8801d94d7c88 00003ffe3bc001e0 00000001cb39b000 [ 24.614843] Call Trace: [ 24.617425] [] zap_huge_pmd+0x16f/0x860 [ 24.623086] [] unmap_page_range+0x12ad/0x1730 [ 24.629221] [] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 24.635530] [] unmap_single_vma+0x101/0x260 [ 24.641488] [] unmap_vmas+0x102/0x1d0 [ 24.646923] [] exit_mmap+0x214/0x3f0 [ 24.652292] [] ? SyS_munmap+0xa0/0xa0 [ 24.657728] [] ? up_write+0x1a/0x60 [ 24.662988] [] mmput+0xf3/0x2d0 [ 24.667904] [] do_exit+0x906/0x27b0 [ 24.673281] [] ? release_task.part.19+0x1210/0x1210 [ 24.679936] [] ? up_write+0x1a/0x60 [ 24.685202] [] ? do_mprotect_pkey+0x71d/0x890 [ 24.691471] [] ? mprotect_fixup+0x930/0x930 [ 24.697429] [] do_group_exit+0x111/0x340 [ 24.703177] [] ? do_group_exit+0x340/0x340 [ 24.709101] [] SyS_exit_group+0x1d/0x20 [ 24.714713] [] do_syscall_64+0x1a6/0x490 [ 24.720408] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 24.727319] Code: 55 41 54 53 48 89 fb e8 c8 b6 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 93 b6 e6 [ 24.755381] RIP [] page_remove_rmap+0x37/0x6d0 [ 24.761734] RSP [ 24.765344] CR2: ffffeafff8ef0020 [ 24.768785] ---[ end trace c334da95d0e183a1 ]--- [ 24.773526] Kernel panic - not syncing: Fatal exception [ 24.779409] Dumping ftrace buffer: [ 24.782943] (ftrace buffer empty) [ 24.786638] Kernel Offset: disabled [ 24.790249] Rebooting in 86400 seconds..