[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 12.308158] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.611434] random: sshd: uninitialized urandom read (32 bytes read) [ 18.869083] random: sshd: uninitialized urandom read (32 bytes read) [ 19.343726] random: sshd: uninitialized urandom read (32 bytes read) [ 37.025098] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.60' (ECDSA) to the list of known hosts. [ 42.512085] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 42.591209] BUG: unable to handle kernel paging request at ffffeafff8f80020 [ 42.598844] IP: [] page_remove_rmap+0x37/0x6d0 [ 42.605103] PGD 0 [ 42.607048] [ 42.608670] Oops: 0000 [#1] PREEMPT SMP KASAN [ 42.613142] Dumping ftrace buffer: [ 42.616658] (ftrace buffer empty) [ 42.620346] Modules linked in: [ 42.623661] CPU: 0 PID: 3801 Comm: syz-executor886 Not tainted 4.9.121-g681e57b #77 [ 42.631423] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.640759] task: ffff8801b8436000 task.stack: ffff8801d9120000 [ 42.646791] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 42.655475] RSP: 0018:ffff8801d9127948 EFLAGS: 00010246 [ 42.660902] RAX: dffffc0000000000 RBX: ffffeafff8f80000 RCX: 0000000000000000 [ 42.668150] RDX: 1ffffd5fff1f0004 RSI: ffffffff814f5278 RDI: ffffeafff8f80000 [ 42.675412] RBP: ffff8801d9127970 R08: 0000000000034120 R09: 0000000000000001 [ 42.682777] R10: ffff8801b8436000 R11: 0000000000000001 R12: ffff8801d9127c08 [ 42.690042] R13: ffffeafff8f80020 R14: ffffeafff8f80000 R15: 0000000000000001 [ 42.697389] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 42.705598] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 42.711454] CR2: ffffeafff8f80020 CR3: 00000001c2326000 CR4: 00000000001606f0 [ 42.718779] Stack: [ 42.720909] ffffeafff8f80020 ffff8801d9127c08 ffff8801c2367800 ffffeafff8f80000 [ 42.728896] ffff8801c569e160 ffff8801d91279c8 ffffffff8154c20f ffff8801d9127c18 [ 42.736873] ffff8801d9127c10 ffff8801d9127c88 00003ffe3e0001e0 00000001c2367000 [ 42.744876] Call Trace: [ 42.747442] [] zap_huge_pmd+0x16f/0x860 [ 42.753043] [] unmap_page_range+0x12ad/0x1730 [ 42.759166] [] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 42.765463] [] unmap_single_vma+0x101/0x260 [ 42.771408] [] unmap_vmas+0x102/0x1d0 [ 42.776838] [] exit_mmap+0x214/0x3f0 [ 42.782183] [] ? SyS_munmap+0xa0/0xa0 [ 42.787611] [] ? up_write+0x1a/0x60 [ 42.792879] [] mmput+0xf3/0x2d0 [ 42.797787] [] do_exit+0x906/0x27b0 [ 42.803042] [] ? release_task.part.19+0x1210/0x1210 [ 42.809693] [] ? up_write+0x1a/0x60 [ 42.814952] [] ? do_mprotect_pkey+0x71d/0x890 [ 42.821205] [] ? mprotect_fixup+0x930/0x930 [ 42.827151] [] do_group_exit+0x111/0x340 [ 42.832839] [] ? do_group_exit+0x340/0x340 [ 42.838699] [] SyS_exit_group+0x1d/0x20 [ 42.844303] [] do_syscall_64+0x1a6/0x490 [ 42.849988] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 42.856885] 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 [ 42.884164] RIP [] page_remove_rmap+0x37/0x6d0 [ 42.890498] RSP [ 42.894209] CR2: ffffeafff8f80020 [ 42.897642] ---[ end trace 98404039e6a6ee03 ]--- [ 42.902369] Kernel panic - not syncing: Fatal exception [ 42.907983] Dumping ftrace buffer: [ 42.911502] (ftrace buffer empty) [ 42.915290] Kernel Offset: disabled [ 42.918893] Rebooting in 86400 seconds..