[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.758423] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 27.601978] random: sshd: uninitialized urandom read (32 bytes read) [ 27.932497] random: sshd: uninitialized urandom read (32 bytes read) [ 28.412456] random: sshd: uninitialized urandom read (32 bytes read) [ 45.906434] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.26' (ECDSA) to the list of known hosts. [ 51.337762] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 51.415011] BUG: unable to handle kernel paging request at ffffeafff9158020 [ 51.422403] IP: [] page_remove_rmap+0x37/0x6d0 [ 51.428658] PGD 0 [ 51.430659] [ 51.432292] Oops: 0000 [#1] PREEMPT SMP KASAN [ 51.436767] Dumping ftrace buffer: [ 51.440338] (ftrace buffer empty) [ 51.444034] Modules linked in: [ 51.447325] CPU: 0 PID: 3811 Comm: syz-executor874 Not tainted 4.9.120-gf85543b #76 [ 51.455094] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.464571] task: ffff8801b8ba3000 task.stack: ffff8801b6808000 [ 51.470618] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 51.479322] RSP: 0018:ffff8801b680f948 EFLAGS: 00010246 [ 51.484876] RAX: dffffc0000000000 RBX: ffffeafff9158000 RCX: 0000000000000000 [ 51.492128] RDX: 1ffffd5fff22b004 RSI: ffffffff814f5128 RDI: ffffeafff9158000 [ 51.499376] RBP: ffff8801b680f970 R08: 00000000000348c0 R09: 0000000000000001 [ 51.506627] R10: ffff8801b8ba3000 R11: 0000000000000001 R12: ffff8801b680fc08 [ 51.513887] R13: ffffeafff9158020 R14: ffffeafff9158000 R15: 0000000000000001 [ 51.521148] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 51.529472] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 51.535340] CR2: ffffeafff9158020 CR3: 00000001c9193000 CR4: 00000000001606f0 [ 51.542594] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 51.549842] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 51.557208] Stack: [ 51.559339] ffffeafff9158020 ffff8801b680fc08 ffff8801c0d31800 ffffeafff9158000 [ 51.567339] ffff8801b8da4840 ffff8801b680f9c8 ffffffff8154bfcf ffff8801b680fc18 [ 51.575368] ffff8801b680fc10 ffff8801b680fc88 00003ffe456001e0 00000001c0d31000 [ 51.583544] Call Trace: [ 51.586116] [] zap_huge_pmd+0x16f/0x860 [ 51.591719] [] unmap_page_range+0x12ad/0x1730 [ 51.597838] [] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 51.604130] [] unmap_single_vma+0x101/0x260 [ 51.610224] [] unmap_vmas+0x102/0x1d0 [ 51.615755] [] exit_mmap+0x214/0x3f0 [ 51.621097] [] ? SyS_munmap+0xa0/0xa0 [ 51.626525] [] ? up_write+0x1a/0x60 [ 51.631781] [] mmput+0xf3/0x2d0 [ 51.636692] [] do_exit+0x906/0x27b0 [ 51.642036] [] ? release_task.part.19+0x1210/0x1210 [ 51.648750] [] ? up_write+0x1a/0x60 [ 51.654007] [] ? do_mprotect_pkey+0x71d/0x890 [ 51.660166] [] ? mprotect_fixup+0x930/0x930 [ 51.666125] [] do_group_exit+0x111/0x340 [ 51.671813] [] ? do_group_exit+0x340/0x340 [ 51.677672] [] SyS_exit_group+0x1d/0x20 [ 51.683269] [] do_syscall_64+0x1a6/0x490 [ 51.689112] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 51.696010] 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 [ 51.723034] RIP [] page_remove_rmap+0x37/0x6d0 [ 51.729363] RSP [ 51.732962] CR2: ffffeafff9158020 [ 51.736392] ---[ end trace 5b2b8f8fc1ab1d9c ]--- [ 51.741127] Kernel panic - not syncing: Fatal exception [ 51.746828] Dumping ftrace buffer: [ 51.750344] (ftrace buffer empty) [ 51.754028] Kernel Offset: disabled [ 51.757672] Rebooting in 86400 seconds..