[....] 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[ 12.571926] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.037042] random: sshd: uninitialized urandom read (32 bytes read) [ 18.343497] random: sshd: uninitialized urandom read (32 bytes read) [ 18.869279] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.16' (ECDSA) to the list of known hosts. [ 24.608533] urandom_read: 1 callbacks suppressed [ 24.608536] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 24.698858] capability: warning: `syz-executor541' uses 32-bit capabilities (legacy support in use) [ 24.708291] BUG: unable to handle kernel paging request at ffffeafff8fb8020 [ 24.715627] IP: [] page_remove_rmap+0x37/0x6d0 [ 24.721884] PGD 0 [ 24.723832] [ 24.725458] Oops: 0000 [#1] PREEMPT SMP KASAN [ 24.730040] Dumping ftrace buffer: [ 24.733685] (ftrace buffer empty) [ 24.737401] Modules linked in: [ 24.740753] CPU: 1 PID: 3745 Comm: syz-executor541 Not tainted 4.9.121-g681e57b #77 [ 24.748526] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.758064] task: ffff8801be451800 task.stack: ffff8801be060000 [ 24.764100] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 24.772785] RSP: 0018:ffff8801be067948 EFLAGS: 00010246 [ 24.778208] RAX: dffffc0000000000 RBX: ffffeafff8fb8000 RCX: 0000000000000000 [ 24.785453] RDX: 1ffffd5fff1f7004 RSI: ffffffff814f5278 RDI: ffffeafff8fb8000 [ 24.792700] RBP: ffff8801be067970 R08: ffff8801be4520e8 R09: 0000000000000001 [ 24.799946] R10: ffff8801be451800 R11: 0000000000000001 R12: ffff8801be067c08 [ 24.807192] R13: ffffeafff8fb8020 R14: ffffeafff8fb8000 R15: 0000000000000001 [ 24.814441] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 24.822637] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 24.828490] CR2: ffffeafff8fb8020 CR3: 000000000461e000 CR4: 00000000001606f0 [ 24.835802] Stack: [ 24.837934] ffffeafff8fb8020 ffff8801be067c08 ffff8801bebcf838 ffffeafff8fb8000 [ 24.845930] ffff8801c08bc790 ffff8801be0679c8 ffffffff8154c20f ffff8801be067c18 [ 24.853948] ffff8801be067c10 ffff8801be067c88 00003ffe3ee001e0 00000001bebcf000 [ 24.861956] Call Trace: [ 24.864529] [] zap_huge_pmd+0x16f/0x860 [ 24.870189] [] unmap_page_range+0x12ad/0x1730 [ 24.876371] [] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 24.882675] [] unmap_single_vma+0x101/0x260 [ 24.888663] [] unmap_vmas+0x102/0x1d0 [ 24.894094] [] exit_mmap+0x214/0x3f0 [ 24.899445] [] ? SyS_munmap+0xa0/0xa0 [ 24.904876] [] ? up_write+0x1a/0x60 [ 24.910128] [] mmput+0xf3/0x2d0 [ 24.915033] [] do_exit+0x906/0x27b0 [ 24.920383] [] ? release_task.part.19+0x1210/0x1210 [ 24.927044] [] ? up_write+0x1a/0x60 [ 24.932325] [] ? do_mprotect_pkey+0x71d/0x890 [ 24.938515] [] ? mprotect_fixup+0x930/0x930 [ 24.944468] [] do_group_exit+0x111/0x340 [ 24.950156] [] ? do_group_exit+0x340/0x340 [ 24.956018] [] SyS_exit_group+0x1d/0x20 [ 24.961623] [] do_syscall_64+0x1a6/0x490 [ 24.967429] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 24.974331] 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 [ 25.001443] RIP [] page_remove_rmap+0x37/0x6d0 [ 25.007780] RSP [ 25.011380] CR2: ffffeafff8fb8020 [ 25.014842] ---[ end trace 8b8177270405bfb0 ]--- [ 25.019570] Kernel panic - not syncing: Fatal exception [ 25.025198] Dumping ftrace buffer: [ 25.028720] (ftrace buffer empty) [ 25.032413] Kernel Offset: disabled [ 25.036030] Rebooting in 86400 seconds..