[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 17.161606] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 21.257633] random: sshd: uninitialized urandom read (32 bytes read) [ 21.743162] random: sshd: uninitialized urandom read (32 bytes read) [ 22.224966] random: sshd: uninitialized urandom read (32 bytes read) [ 22.358608] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.31' (ECDSA) to the list of known hosts. [ 27.963343] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 28.058986] BUG: unable to handle kernel paging request at ffffeafff91e8020 [ 28.066430] IP: [] page_remove_rmap+0x37/0x6d0 [ 28.072670] PGD 0 [ 28.074615] [ 28.076239] Oops: 0000 [#1] PREEMPT SMP KASAN [ 28.080710] Dumping ftrace buffer: [ 28.084217] (ftrace buffer empty) [ 28.087900] Modules linked in: [ 28.091185] CPU: 0 PID: 3801 Comm: syz-executor394 Not tainted 4.9.120-gf85543b #24 [ 28.098949] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.108283] task: ffff8801b6c3b000 task.stack: ffff8801c9340000 [ 28.114311] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 28.123010] RSP: 0018:ffff8801c9347948 EFLAGS: 00010246 [ 28.128430] RAX: dffffc0000000000 RBX: ffffeafff91e8000 RCX: ffffea0006d18000 [ 28.135687] RDX: 1ffffd5fff23d004 RSI: ffffffff814f5128 RDI: ffffeafff91e8000 [ 28.142929] RBP: ffff8801c9347970 R08: 0000000000033f00 R09: 0000000000000001 [ 28.150172] R10: ffff8801b6c3b000 R11: 0000000000000001 R12: ffff8801c9347c08 [ 28.157414] R13: ffffeafff91e8020 R14: ffffeafff91e8000 R15: 0000000000000001 [ 28.164659] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 28.172856] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 28.178707] CR2: ffffeafff91e8020 CR3: 00000001b89d7000 CR4: 00000000001606f0 [ 28.185988] Stack: [ 28.188112] ffffeafff91e8020 ffff8801c9347c08 ffff8801b71e1808 ffffeafff91e8000 [ 28.196131] ffff8801b72c0b00 ffff8801c93479c8 ffffffff8154bfcf ffff8801c9347c18 [ 28.204134] ffff8801c9347c10 ffff8801c9347c88 00003ffe47a001e0 ffff8801c9347ae8 [ 28.212154] Call Trace: [ 28.214717] [] zap_huge_pmd+0x16f/0x860 [ 28.220317] [] unmap_page_range+0x12ad/0x1730 [ 28.226436] [] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 28.232726] [] unmap_single_vma+0x101/0x260 [ 28.238693] [] unmap_vmas+0x102/0x1d0 [ 28.244115] [] exit_mmap+0x214/0x3f0 [ 28.249450] [] ? SyS_munmap+0xa0/0xa0 [ 28.254875] [] ? up_write+0x1a/0x60 [ 28.260123] [] mmput+0xf3/0x2d0 [ 28.265115] [] do_exit+0x906/0x27b0 [ 28.270389] [] ? release_task.part.19+0x1210/0x1210 [ 28.277028] [] ? up_write+0x1a/0x60 [ 28.282276] [] ? do_mprotect_pkey+0x71d/0x890 [ 28.288390] [] ? mprotect_fixup+0x930/0x930 [ 28.294332] [] do_group_exit+0x111/0x340 [ 28.300015] [] ? do_group_exit+0x340/0x340 [ 28.305877] [] SyS_exit_group+0x1d/0x20 [ 28.311472] [] do_syscall_64+0x1a6/0x490 [ 28.317166] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 28.324061] 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 [ 28.351071] RIP [] page_remove_rmap+0x37/0x6d0 [ 28.357410] RSP [ 28.361005] CR2: ffffeafff91e8020 [ 28.364434] ---[ end trace 473c2422ba0b1241 ]--- [ 28.369163] Kernel panic - not syncing: Fatal exception [ 28.374805] Dumping ftrace buffer: [ 28.378322] (ftrace buffer empty) [ 28.382008] Kernel Offset: disabled [ 28.385607] Rebooting in 86400 seconds..