[....] 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[ 13.113471] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 14.393476] random: sshd: uninitialized urandom read (32 bytes read) [ 14.570599] random: sshd: uninitialized urandom read (32 bytes read) [ 15.069141] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.2' (ECDSA) to the list of known hosts. [ 20.975561] urandom_read: 1 callbacks suppressed [ 20.975564] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 21.060732] BUG: unable to handle kernel paging request at ffffeafff8e30020 [ 21.068090] IP: [] page_remove_rmap+0x37/0x6d0 [ 21.074356] PGD 0 [ 21.076301] [ 21.077923] Oops: 0000 [#1] PREEMPT SMP KASAN [ 21.082399] Dumping ftrace buffer: [ 21.085933] (ftrace buffer empty) [ 21.089623] Modules linked in: [ 21.092913] CPU: 1 PID: 3661 Comm: syz-executor253 Not tainted 4.9.121-g681e57b #77 [ 21.100679] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.110011] task: ffff8801c4490000 task.stack: ffff8801cf328000 [ 21.116040] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 21.124730] RSP: 0018:ffff8801cf32f948 EFLAGS: 00010246 [ 21.130156] RAX: dffffc0000000000 RBX: ffffeafff8e30000 RCX: 0000000000000000 [ 21.137420] RDX: 1ffffd5fff1c6004 RSI: ffffffff814f5278 RDI: ffffeafff8e30000 [ 21.144666] RBP: ffff8801cf32f970 R08: 0000000000034360 R09: 0000000000000001 [ 21.151928] R10: ffff8801c4490000 R11: 0000000000000001 R12: ffff8801cf32fc08 [ 21.159177] R13: ffffeafff8e30020 R14: ffffeafff8e30000 R15: 0000000000000001 [ 21.166421] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 21.174624] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 21.180482] CR2: ffffeafff8e30020 CR3: 00000001c3545000 CR4: 00000000001606f0 [ 21.187744] Stack: [ 21.189872] ffffeafff8e30020 ffff8801cf32fc08 ffff8801c44ae800 ffffeafff8e30000 [ 21.197856] ffff8801c343b8f0 ffff8801cf32f9c8 ffffffff8154c20f ffff8801cf32fc18 [ 21.205864] ffff8801cf32fc10 ffff8801cf32fc88 00003ffe38c001e0 00000001c44ae000 [ 21.213856] Call Trace: [ 21.216432] [] zap_huge_pmd+0x16f/0x860 [ 21.222032] [] unmap_page_range+0x12ad/0x1730 [ 21.228154] [] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 21.234451] [] unmap_single_vma+0x101/0x260 [ 21.240425] [] unmap_vmas+0x102/0x1d0 [ 21.245868] [] exit_mmap+0x214/0x3f0 [ 21.251260] [] ? SyS_munmap+0xa0/0xa0 [ 21.256686] [] ? up_write+0x1a/0x60 [ 21.261951] [] mmput+0xf3/0x2d0 [ 21.266854] [] do_exit+0x906/0x27b0 [ 21.272107] [] ? release_task.part.19+0x1210/0x1210 [ 21.278748] [] ? up_write+0x1a/0x60 [ 21.283998] [] ? do_mprotect_pkey+0x71d/0x890 [ 21.290120] [] ? mprotect_fixup+0x930/0x930 [ 21.296063] [] do_group_exit+0x111/0x340 [ 21.301750] [] ? do_group_exit+0x340/0x340 [ 21.307609] [] SyS_exit_group+0x1d/0x20 [ 21.313213] [] do_syscall_64+0x1a6/0x490 [ 21.318906] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 21.325805] 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 [ 21.352541] RIP [] page_remove_rmap+0x37/0x6d0 [ 21.358892] RSP [ 21.362503] CR2: ffffeafff8e30020 [ 21.365960] ---[ end trace cde504982250c7b3 ]--- [ 21.370688] Kernel panic - not syncing: Fatal exception [ 21.376341] Dumping ftrace buffer: [ 21.379863] (ftrace buffer empty) [ 21.383547] Kernel Offset: disabled [ 21.387146] Rebooting in 86400 seconds..