[....] 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[ 15.248182] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 21.927871] random: sshd: uninitialized urandom read (32 bytes read) [ 22.200250] random: sshd: uninitialized urandom read (32 bytes read) [ 22.644436] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.56' (ECDSA) to the list of known hosts. [ 28.304657] urandom_read: 1 callbacks suppressed [ 28.304660] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 28.390361] BUG: unable to handle kernel paging request at ffffeafff8fe8020 [ 28.397832] IP: [] page_remove_rmap+0x37/0x6d0 [ 28.404079] PGD 0 [ 28.406031] [ 28.407665] Oops: 0000 [#1] PREEMPT SMP KASAN [ 28.412135] Dumping ftrace buffer: [ 28.415648] (ftrace buffer empty) [ 28.419422] Modules linked in: [ 28.422709] CPU: 1 PID: 3795 Comm: syz-executor404 Not tainted 4.9.122-g54068d6 #78 [ 28.430475] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.439806] task: ffff8801b8e74800 task.stack: ffff8801b7528000 [ 28.445834] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 28.454508] RSP: 0018:ffff8801b752f948 EFLAGS: 00010246 [ 28.459934] RAX: dffffc0000000000 RBX: ffffeafff8fe8000 RCX: 0000000000000000 [ 28.467180] RDX: 1ffffd5fff1fd004 RSI: ffffffff814f5918 RDI: ffffeafff8fe8000 [ 28.474422] RBP: ffff8801b752f970 R08: 00000000000348c0 R09: 0000000000000001 [ 28.481667] R10: ffff8801b8e74800 R11: 0000000000000001 R12: ffff8801b752fc08 [ 28.488910] R13: ffffeafff8fe8020 R14: ffffeafff8fe8000 R15: 0000000000000001 [ 28.496161] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 28.504368] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 28.510229] CR2: ffffeafff8fe8020 CR3: 00000001c1f7d000 CR4: 00000000001606f0 [ 28.517482] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 28.524784] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 28.532037] Stack: [ 28.534176] ffffeafff8fe8020 ffff8801b752fc08 ffff8801c0ba8800 ffffeafff8fe8000 [ 28.542171] ffff8801b89d6f20 ffff8801b752f9c8 ffffffff8154cb8f ffff8801b752fc18 [ 28.550237] ffff8801b752fc10 ffff8801b752fc88 00003ffe3fa001e0 00000001c0ba8000 [ 28.558232] Call Trace: [ 28.560841] [] zap_huge_pmd+0x16f/0x860 [ 28.566446] [] unmap_page_range+0x12ad/0x1730 [ 28.572565] [] ? vm_normal_page_pmd+0x310/0x310 [ 28.578862] [] unmap_single_vma+0x101/0x260 [ 28.584810] [] unmap_vmas+0x102/0x1d0 [ 28.590234] [] exit_mmap+0x214/0x3f0 [ 28.595572] [] ? SyS_munmap+0xa0/0xa0 [ 28.600996] [] ? up_write+0x1a/0x60 [ 28.606253] [] mmput+0xf3/0x2d0 [ 28.611203] [] do_exit+0x906/0x27b0 [ 28.616462] [] ? release_task.part.19+0x1210/0x1210 [ 28.623106] [] ? up_write+0x1a/0x60 [ 28.628359] [] ? do_mprotect_pkey+0x71d/0x890 [ 28.634480] [] ? mprotect_fixup+0x930/0x930 [ 28.640436] [] do_group_exit+0x111/0x340 [ 28.646125] [] ? do_group_exit+0x340/0x340 [ 28.651984] [] SyS_exit_group+0x1d/0x20 [ 28.657582] [] do_syscall_64+0x1a6/0x490 [ 28.663267] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 28.670164] Code: 55 41 54 53 48 89 fb e8 58 b4 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 23 b4 e6 [ 28.697172] RIP [] page_remove_rmap+0x37/0x6d0 [ 28.703501] RSP [ 28.707101] CR2: ffffeafff8fe8020 [ 28.710534] ---[ end trace 6f1b5e4c2784df7e ]--- [ 28.715261] Kernel panic - not syncing: Fatal exception [ 28.720950] Dumping ftrace buffer: [ 28.724465] (ftrace buffer empty) [ 28.728147] Kernel Offset: disabled [ 28.731787] Rebooting in 86400 seconds..