[....] 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[ 13.533499] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 19.394595] random: sshd: uninitialized urandom read (32 bytes read) [ 19.745608] random: sshd: uninitialized urandom read (32 bytes read) [ 20.184939] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.18' (ECDSA) to the list of known hosts. [ 25.998665] urandom_read: 1 callbacks suppressed [ 25.998668] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 26.083881] BUG: unable to handle kernel paging request at ffffeafff91b8020 [ 26.091228] IP: [] page_remove_rmap+0x37/0x6d0 [ 26.097470] PGD 0 [ 26.099414] [ 26.101035] Oops: 0000 [#1] PREEMPT SMP KASAN [ 26.105542] Dumping ftrace buffer: [ 26.109059] (ftrace buffer empty) [ 26.112742] Modules linked in: [ 26.116024] CPU: 1 PID: 3804 Comm: syz-executor815 Not tainted 4.9.120-gf85543b #76 [ 26.123786] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.133117] task: ffff8801b72b4800 task.stack: ffff8801b5a60000 [ 26.139146] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 26.147816] RSP: 0018:ffff8801b5a67948 EFLAGS: 00010246 [ 26.153241] RAX: dffffc0000000000 RBX: ffffeafff91b8000 RCX: ffffea0006e40000 [ 26.160486] RDX: 1ffffd5fff237004 RSI: ffffffff814f5128 RDI: ffffeafff91b8000 [ 26.167729] RBP: ffff8801b5a67970 R08: 0000000000033e20 R09: 0000000000000001 [ 26.174972] R10: ffff8801b72b4800 R11: 0000000000000001 R12: ffff8801b5a67c08 [ 26.182215] R13: ffffeafff91b8020 R14: ffffeafff91b8000 R15: 0000000000000001 [ 26.189458] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 26.197654] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 26.203511] CR2: ffffeafff91b8020 CR3: 00000001c398c000 CR4: 00000000001606f0 [ 26.210761] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 26.218068] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 26.225315] Stack: [ 26.227440] ffffeafff91b8020 ffff8801b5a67c08 ffff8801c3a5d810 ffffeafff91b8000 [ 26.235436] ffff8801b6ddc7e8 ffff8801b5a679c8 ffffffff8154bfcf ffff8801b5a67c18 [ 26.243415] ffff8801b5a67c10 ffff8801b5a67c88 00003ffe46e001a0 00000001c3a5d000 [ 26.251395] Call Trace: [ 26.253958] [] zap_huge_pmd+0x16f/0x860 [ 26.259559] [] unmap_page_range+0x12ad/0x1730 [ 26.265675] [] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 26.271966] [] ? _raw_spin_unlock_irqrestore+0x5a/0x70 [ 26.278865] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 26.285679] [] unmap_single_vma+0x101/0x260 [ 26.291626] [] unmap_vmas+0x102/0x1d0 [ 26.297047] [] exit_mmap+0x214/0x3f0 [ 26.302385] [] ? SyS_munmap+0xa0/0xa0 [ 26.307809] [] ? up_write+0x1a/0x60 [ 26.313058] [] mmput+0xf3/0x2d0 [ 26.317963] [] do_exit+0x906/0x27b0 [ 26.323268] [] ? release_task.part.19+0x1210/0x1210 [ 26.329920] [] ? up_write+0x1a/0x60 [ 26.335177] [] ? do_mprotect_pkey+0x71d/0x890 [ 26.341296] [] ? mprotect_fixup+0x930/0x930 [ 26.347240] [] do_group_exit+0x111/0x340 [ 26.352924] [] ? do_group_exit+0x340/0x340 [ 26.358783] [] SyS_exit_group+0x1d/0x20 [ 26.364490] [] do_syscall_64+0x1a6/0x490 [ 26.370180] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 26.377084] 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 [ 26.403909] RIP [] page_remove_rmap+0x37/0x6d0 [ 26.410244] RSP [ 26.413841] CR2: ffffeafff91b8020 [ 26.417269] ---[ end trace dd3c9053ab9718bb ]--- [ 26.421996] Kernel panic - not syncing: Fatal exception [ 26.427740] Dumping ftrace buffer: [ 26.431259] (ftrace buffer empty) [ 26.434941] Kernel Offset: disabled [ 26.438539] Rebooting in 86400 seconds..