[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.653187] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 25.747863] random: sshd: uninitialized urandom read (32 bytes read) [ 26.173434] random: sshd: uninitialized urandom read (32 bytes read) [ 26.699288] random: sshd: uninitialized urandom read (32 bytes read) [ 26.840595] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.31' (ECDSA) to the list of known hosts. [ 32.311886] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 32.398245] capability: warning: `syz-executor542' uses 32-bit capabilities (legacy support in use) [ 32.407795] BUG: unable to handle kernel paging request at ffffeafff9150020 [ 32.415164] IP: [] page_remove_rmap+0x37/0x6d0 [ 32.421421] PGD 0 [ 32.423367] [ 32.424996] Oops: 0000 [#1] PREEMPT SMP KASAN [ 32.429527] Dumping ftrace buffer: [ 32.433049] (ftrace buffer empty) [ 32.436737] Modules linked in: [ 32.440032] CPU: 1 PID: 3799 Comm: syz-executor542 Not tainted 4.9.121-g681e57b #25 [ 32.448235] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.457611] task: ffff8801b80a3000 task.stack: ffff8801d98b0000 [ 32.463652] RIP: 0010:[] [] page_remove_rmap+0x37/0x6d0 [ 32.472353] RSP: 0018:ffff8801d98b7948 EFLAGS: 00010246 [ 32.477870] RAX: dffffc0000000000 RBX: ffffeafff9150000 RCX: 0000000000000000 [ 32.485117] RDX: 1ffffd5fff22a004 RSI: ffffffff814f5278 RDI: ffffeafff9150000 [ 32.492460] RBP: ffff8801d98b7970 R08: ffff8801b80a38e8 R09: 0000000000000001 [ 32.499709] R10: ffff8801b80a3000 R11: 0000000000000001 R12: ffff8801d98b7c08 [ 32.507073] R13: ffffeafff9150020 R14: ffffeafff9150000 R15: 0000000000000001 [ 32.514323] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 32.522578] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 32.528442] CR2: ffffeafff9150020 CR3: 000000000461e000 CR4: 00000000001606f0 [ 32.535697] Stack: [ 32.537842] ffffeafff9150020 ffff8801d98b7c08 ffff8801b8072838 ffffeafff9150000 [ 32.545950] ffff8801c9077d68 ffff8801d98b79c8 ffffffff8154c20f ffff8801d98b7c18 [ 32.553971] ffff8801d98b7c10 ffff8801d98b7c88 00003ffe454001e0 00000001b8072000 [ 32.562025] Call Trace: [ 32.564641] [] zap_huge_pmd+0x16f/0x860 [ 32.570247] [] unmap_page_range+0x12ad/0x1730 [ 32.576367] [] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 32.582728] [] unmap_single_vma+0x101/0x260 [ 32.588694] [] unmap_vmas+0x102/0x1d0 [ 32.594253] [] exit_mmap+0x214/0x3f0 [ 32.599689] [] ? SyS_munmap+0xa0/0xa0 [ 32.605120] [] ? up_write+0x1a/0x60 [ 32.610372] [] mmput+0xf3/0x2d0 [ 32.615277] [] do_exit+0x906/0x27b0 [ 32.620532] [] ? release_task.part.19+0x1210/0x1210 [ 32.627182] [] ? up_write+0x1a/0x60 [ 32.632437] [] ? do_mprotect_pkey+0x71d/0x890 [ 32.638558] [] ? mprotect_fixup+0x930/0x930 [ 32.644511] [] do_group_exit+0x111/0x340 [ 32.650204] [] ? do_group_exit+0x340/0x340 [ 32.656071] [] SyS_exit_group+0x1d/0x20 [ 32.661676] [] do_syscall_64+0x1a6/0x490 [ 32.667377] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 32.674298] 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 [ 32.701781] RIP [] page_remove_rmap+0x37/0x6d0 [ 32.708126] RSP [ 32.711723] CR2: ffffeafff9150020 [ 32.715157] ---[ end trace 34065fe6ec9851e3 ]--- [ 32.719890] Kernel panic - not syncing: Fatal exception [ 32.725549] Dumping ftrace buffer: [ 32.729081] (ftrace buffer empty) [ 32.732770] Kernel Offset: disabled [ 32.736417] Rebooting in 86400 seconds..