[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.026287] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. [ 13.700104] random: sshd: uninitialized urandom read (32 bytes read) [ 13.923384] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 14.766991] random: sshd: uninitialized urandom read (32 bytes read) [ 14.909004] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.9' (ECDSA) to the list of known hosts. [ 20.389824] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 20.474007] BUG: unable to handle kernel paging request at ffffeafff8e38020 [ 20.481389] IP: [] page_remove_rmap+0x37/0x6d0 [ 20.487651] PGD 0 [ 20.489608] [ 20.491266] Oops: 0000 [#1] PREEMPT SMP KASAN [ 20.495745] Dumping ftrace buffer: [ 20.499272] (ftrace buffer empty) [ 20.503032] Modules linked in: [ 20.506341] CPU: 0 PID: 3798 Comm: syz-executor477 Not tainted 4.9.121-g681e57b #25 [ 20.514122] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 20.523511] task: ffff8801b7acb000 task.stack: ffff8801b5f18000 [ 20.529560] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 20.538335] RSP: 0018:ffff8801b5f1f948 EFLAGS: 00010246 [ 20.543781] RAX: dffffc0000000000 RBX: ffffeafff8e38000 RCX: 0000000000000000 [ 20.551046] RDX: 1ffffd5fff1c7004 RSI: ffffffff814f5278 RDI: ffffeafff8e38000 [ 20.558367] RBP: ffff8801b5f1f970 R08: 0000000000033cc0 R09: 0000000000000001 [ 20.565623] R10: ffff8801b7acb000 R11: 0000000000000001 R12: ffff8801b5f1fc08 [ 20.572884] R13: ffffeafff8e38020 R14: ffffeafff8e38000 R15: 0000000000000001 [ 20.580155] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 20.588366] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 20.594247] CR2: ffffeafff8e38020 CR3: 00000001c08e3000 CR4: 00000000001606f0 [ 20.601509] Stack: [ 20.603641] ffffeafff8e38020 ffff8801b5f1fc08 ffff8801c0b5b800 ffffeafff8e38000 [ 20.611675] ffff8801b6ecc1b8 ffff8801b5f1f9c8 ffffffff8154c20f ffff8801b5f1fc18 [ 20.619741] ffff8801b5f1fc10 ffff8801b5f1fc88 00003ffe38e001e0 00000001c0b5b000 [ 20.627811] Call Trace: [ 20.630388] [] zap_huge_pmd+0x16f/0x860 [ 20.636101] [] unmap_page_range+0x12ad/0x1730 [ 20.642368] [] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 20.648672] [] unmap_single_vma+0x101/0x260 [ 20.654627] [] unmap_vmas+0x102/0x1d0 [ 20.660064] [] exit_mmap+0x214/0x3f0 [ 20.665410] [] ? SyS_munmap+0xa0/0xa0 [ 20.670848] [] ? up_write+0x1a/0x60 [ 20.676107] [] mmput+0xf3/0x2d0 [ 20.681022] [] do_exit+0x906/0x27b0 [ 20.686284] [] ? release_task.part.19+0x1210/0x1210 [ 20.692936] [] ? up_write+0x1a/0x60 [ 20.698198] [] ? do_mprotect_pkey+0x71d/0x890 [ 20.704328] [] ? mprotect_fixup+0x930/0x930 [ 20.710285] [] do_group_exit+0x111/0x340 [ 20.715979] [] ? do_group_exit+0x340/0x340 [ 20.721847] [] SyS_exit_group+0x1d/0x20 [ 20.727456] [] do_syscall_64+0x1a6/0x490 [ 20.733153] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 20.740060] 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 [ 20.767665] RIP [] page_remove_rmap+0x37/0x6d0 [ 20.774009] RSP [ 20.777615] CR2: ffffeafff8e38020 [ 20.781052] ---[ end trace 1ae9b69edd1f9d37 ]--- [ 20.785788] Kernel panic - not syncing: Fatal exception [ 20.791489] Dumping ftrace buffer: [ 20.795019] (ftrace buffer empty) [ 20.798723] Kernel Offset: disabled [ 20.802332] Rebooting in 86400 seconds..