[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 12.755074] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.496959] random: sshd: uninitialized urandom read (32 bytes read) [ 18.823385] random: sshd: uninitialized urandom read (32 bytes read) [ 19.398026] random: sshd: uninitialized urandom read (32 bytes read) [ 35.929313] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.20' (ECDSA) to the list of known hosts. [ 41.593117] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 41.679094] BUG: unable to handle kernel paging request at ffffeafff9040020 [ 41.686522] IP: [] page_remove_rmap+0x37/0x6d0 [ 41.692789] PGD 0 [ 41.694738] [ 41.696370] Oops: 0000 [#1] PREEMPT SMP KASAN [ 41.700840] Dumping ftrace buffer: [ 41.704563] (ftrace buffer empty) [ 41.708254] Modules linked in: [ 41.711543] CPU: 1 PID: 3701 Comm: syz-executor291 Not tainted 4.9.120-gf85543b #76 [ 41.719311] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.728648] task: ffff8801c1f44800 task.stack: ffff8801c1038000 [ 41.734680] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 41.743433] RSP: 0018:ffff8801c103f948 EFLAGS: 00010246 [ 41.748912] RAX: dffffc0000000000 RBX: ffffeafff9040000 RCX: ffffea0006fb8000 [ 41.756170] RDX: 1ffffd5fff208004 RSI: ffffffff814f5128 RDI: ffffeafff9040000 [ 41.763422] RBP: ffff8801c103f970 R08: 0000000000033a80 R09: 0000000000000001 [ 41.770673] R10: ffff8801c1f44800 R11: 0000000000000001 R12: ffff8801c103fc08 [ 41.777939] R13: ffffeafff9040020 R14: ffffeafff9040000 R15: 0000000000000001 [ 41.785387] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 41.793598] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 41.799465] CR2: ffffeafff9040020 CR3: 00000001ca027000 CR4: 00000000001606f0 [ 41.806786] Stack: [ 41.808929] ffffeafff9040020 ffff8801c103fc08 ffff8801cad1b810 ffffeafff9040000 [ 41.816928] ffff8801c5e7c5d8 ffff8801c103f9c8 ffffffff8154bfcf ffff8801c103fc18 [ 41.824939] ffff8801c103fc10 ffff8801c103fc88 00003ffe410001a0 00000001cad1b000 [ 41.832930] Call Trace: [ 41.835499] [] zap_huge_pmd+0x16f/0x860 [ 41.841408] [] unmap_page_range+0x12ad/0x1730 [ 41.847546] [] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 41.853845] [] ? _raw_spin_unlock_irqrestore+0x5a/0x70 [ 41.860767] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 41.867593] [] unmap_single_vma+0x101/0x260 [ 41.873551] [] unmap_vmas+0x102/0x1d0 [ 41.878992] [] exit_mmap+0x214/0x3f0 [ 41.884338] [] ? SyS_munmap+0xa0/0xa0 [ 41.889782] [] ? up_write+0x1a/0x60 [ 41.895042] [] mmput+0xf3/0x2d0 [ 41.899951] [] do_exit+0x906/0x27b0 [ 41.905242] [] ? release_task.part.19+0x1210/0x1210 [ 41.911900] [] ? up_write+0x1a/0x60 [ 41.917156] [] ? do_mprotect_pkey+0x71d/0x890 [ 41.923274] [] ? mprotect_fixup+0x930/0x930 [ 41.929225] [] do_group_exit+0x111/0x340 [ 41.934913] [] ? do_group_exit+0x340/0x340 [ 41.940781] [] SyS_exit_group+0x1d/0x20 [ 41.946385] [] do_syscall_64+0x1a6/0x490 [ 41.952076] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 41.958975] 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 [ 41.985768] RIP [] page_remove_rmap+0x37/0x6d0 [ 41.992104] RSP [ 41.995701] CR2: ffffeafff9040020 [ 41.999177] ---[ end trace 1a12ff4644121695 ]--- [ 42.003912] Kernel panic - not syncing: Fatal exception [ 42.009583] Dumping ftrace buffer: [ 42.013101] (ftrace buffer empty) [ 42.016788] Kernel Offset: disabled [ 42.020395] Rebooting in 86400 seconds..