[....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.343594] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 17.006068] random: sshd: uninitialized urandom read (32 bytes read) [ 17.308900] random: sshd: uninitialized urandom read (32 bytes read) [ 17.812327] random: sshd: uninitialized urandom read (32 bytes read) [ 39.163218] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.34' (ECDSA) to the list of known hosts. [ 44.742554] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 44.828056] BUG: unable to handle kernel paging request at ffffeafff8e58020 [ 44.835439] IP: [<ffffffff814f5297>] page_remove_rmap+0x37/0x6d0 [ 44.841683] PGD 0 [ 44.843632] [ 44.845266] Oops: 0000 [#1] PREEMPT SMP KASAN [ 44.849737] Dumping ftrace buffer: [ 44.853253] (ftrace buffer empty) [ 44.856939] Modules linked in: [ 44.860238] CPU: 1 PID: 3666 Comm: syz-executor939 Not tainted 4.9.121-g681e57b #77 [ 44.868003] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.877334] task: ffff8801c54d1800 task.stack: ffff8801c3400000 [ 44.883365] RIP: 0010:[<ffffffff814f5297>] [<ffffffff814f5297>] page_remove_rmap+0x37/0x6d0 [ 44.892055] RSP: 0018:ffff8801c3407948 EFLAGS: 00010246 [ 44.897476] RAX: dffffc0000000000 RBX: ffffeafff8e58000 RCX: 0000000000000000 [ 44.904719] RDX: 1ffffd5fff1cb004 RSI: ffffffff814f5278 RDI: ffffeafff8e58000 [ 44.912080] RBP: ffff8801c3407970 R08: 0000000000034220 R09: 0000000000000001 [ 44.919327] R10: ffff8801c54d1800 R11: 0000000000000001 R12: ffff8801c3407c08 [ 44.926574] R13: ffffeafff8e58020 R14: ffffeafff8e58000 R15: 0000000000000001 [ 44.933818] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 44.942036] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 44.947891] CR2: ffffeafff8e58020 CR3: 00000001c590b000 CR4: 00000000001606f0 [ 44.955149] Stack: [ 44.957272] ffffeafff8e58020 ffff8801c3407c08 ffff8801c7157800 ffffeafff8e58000 [ 44.965266] ffff8801c3db5948 ffff8801c34079c8 ffffffff8154c20f ffff8801c3407c18 [ 44.973323] ffff8801c3407c10 ffff8801c3407c88 00003ffe396001e0 00000001c7157000 [ 44.981410] Call Trace: [ 44.983975] [<ffffffff8154c20f>] zap_huge_pmd+0x16f/0x860 [ 44.989583] [<ffffffff814ca95d>] unmap_page_range+0x12ad/0x1730 [ 44.995709] [<ffffffff814c96b0>] ? vm_normal_page_pmd+0x2f0/0x2f0 [ 45.002084] [<ffffffff814caee1>] unmap_single_vma+0x101/0x260 [ 45.008039] [<ffffffff814cb822>] unmap_vmas+0x102/0x1d0 [ 45.013467] [<ffffffff814e4214>] exit_mmap+0x214/0x3f0 [ 45.018807] [<ffffffff814e4000>] ? SyS_munmap+0xa0/0xa0 [ 45.024282] [<ffffffff8122e15a>] ? up_write+0x1a/0x60 [ 45.029550] [<ffffffff8112d6f3>] mmput+0xf3/0x2d0 [ 45.034459] [<ffffffff81142c26>] do_exit+0x906/0x27b0 [ 45.039722] [<ffffffff81142320>] ? release_task.part.19+0x1210/0x1210 [ 45.046365] [<ffffffff8122e15a>] ? up_write+0x1a/0x60 [ 45.051617] [<ffffffff814ec78d>] ? do_mprotect_pkey+0x71d/0x890 [ 45.057739] [<ffffffff814ec070>] ? mprotect_fixup+0x930/0x930 [ 45.063709] [<ffffffff81148de1>] do_group_exit+0x111/0x340 [ 45.069411] [<ffffffff81149010>] ? do_group_exit+0x340/0x340 [ 45.075272] [<ffffffff8114902d>] SyS_exit_group+0x1d/0x20 [ 45.080873] [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 [ 45.086567] [<ffffffff839ffcd3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 45.093466] 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 [ 45.120394] RIP [<ffffffff814f5297>] page_remove_rmap+0x37/0x6d0 [ 45.126731] RSP <ffff8801c3407948> [ 45.130328] CR2: ffffeafff8e58020 [ 45.133760] ---[ end trace f6b3cc31b6d7f1a8 ]--- [ 45.138487] Kernel panic - not syncing: Fatal exception [ 45.144205] Dumping ftrace buffer: [ 45.147732] (ftrace buffer empty) [ 45.151415] Kernel Offset: disabled [ 45.155016] Rebooting in 86400 seconds..