[....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 16.402898] 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: [ 22.338913] random: sshd: uninitialized urandom read (32 bytes read) [ 22.819676] random: sshd: uninitialized urandom read (32 bytes read) [ 23.629310] random: sshd: uninitialized urandom read (32 bytes read) [ 31.766095] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.57' (ECDSA) to the list of known hosts. [ 37.398661] random: sshd: uninitialized urandom read (32 bytes read) 2018/05/19 07:07:30 parsed 1 programs 2018/05/19 07:07:30 executed programs: 0 [ 37.875284] IPVS: Creating netns size=2536 id=1 [ 37.957546] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 37.969029] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 38.010658] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 38.022281] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 38.067816] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 38.079243] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 38.090963] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 38.111559] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 38.610075] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 38.636366] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 38.642564] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 38.649408] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 38.936545] syz-executor0 (4174) used greatest stack depth: 23384 bytes left 2018/05/19 07:07:35 executed programs: 75 2018/05/19 07:07:40 executed programs: 175 [ 48.684393] random: crng init done 2018/05/19 07:07:45 executed programs: 281 2018/05/19 07:07:50 executed programs: 368 [ 62.712629] ------------[ cut here ]------------ [ 62.717397] kernel BUG at fs/ext4/inode.c:2630! [ 62.722039] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 62.727397] Dumping ftrace buffer: [ 62.730911] (ftrace buffer empty) [ 62.734953] Modules linked in: [ 62.738283] CPU: 1 PID: 5970 Comm: syz-executor0 Not tainted 4.9.100-ge14d1a3 #30 [ 62.745874] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.755559] task: ffff8801cd2f6000 task.stack: ffff8801cb500000 [ 62.761598] RIP: 0010:[] [] mpage_prepare_extent_to_map+0x7f8/0xa40 [ 62.771317] RSP: 0018:ffff8801cb5073b0 EFLAGS: 00010293 [ 62.777002] RAX: ffff8801cd2f6000 RBX: ffffea0006e651c0 RCX: 0000000000000000 [ 62.784249] RDX: 0000000000000000 RSI: ffffffff8173cde8 RDI: ffffea0006e651c8 [ 62.791586] RBP: ffff8801cb507578 R08: ffff8801cd2f6938 R09: 0000000000000001 [ 62.799191] R10: 0000000000000000 R11: 1ffff10039a5ed22 R12: 0000000000000009 [ 62.806438] R13: 0000000000000000 R14: ffff8801cb5076e0 R15: dffffc0000000000 [ 62.813684] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 62.821884] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 62.827751] CR2: 000000000814b021 CR3: 000000000461e000 CR4: 00000000001606f0 [ 62.835001] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 62.842250] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 62.849506] Stack: [ 62.851631] 1ffff100396a0e86 ffff8801cb5076e8 ffff8801cb507450 ffff8801cb5076f0 [ 62.859648] 00000000cd2f68c0 ffff8801ba9f9c30 000000010000000c 7fffffffffffffff [ 62.867638] ffff8801cb507490 ffff8801cb5076f8 ffffea0006e651d0 ffffed00396a0edd [ 62.875638] Call Trace: [ 62.878214] [] ? ext4_journalled_zero_new_buffers+0x3a0/0x3a0 [ 62.885737] [] ? __lock_is_held+0xa2/0xf0 [ 62.891518] [] ? __lock_is_held+0xa2/0xf0 [ 62.897294] [] ext4_writepages+0xdb9/0x2e50 [ 62.903239] [] ? do_writepages+0xef/0x1d0 [ 62.909010] [] ? __unwind_start+0x14d/0x3c0 [ 62.914953] [] ? unwind_next_frame+0x86/0xe0 [ 62.920987] [] ? ext4_mark_inode_dirty+0xb40/0xb40 [ 62.927539] [] ? __unwind_start+0x14d/0x3c0 [ 62.933483] [] ? depot_save_stack+0x132/0x460 [ 62.939599] [] ? ext4_mark_inode_dirty+0xb40/0xb40 [ 62.946151] [] do_writepages+0xef/0x1d0 [ 62.951746] [] ? page_writeback_cpu_online+0x20/0x20 [ 62.958473] [] ? exit_fs+0xe9/0x120 [ 62.963825] [] ? do_exit+0x9bb/0x27c0 [ 62.969257] [] ? do_group_exit+0x111/0x340 [ 62.975122] [] ? get_signal+0x4cf/0x1450 [ 62.980830] [] ? do_signal+0x87/0x19f0 [ 62.986346] [] ? exit_to_usermode_loop+0xe1/0x120 [ 62.992813] [] ? do_fast_syscall_32+0x5c3/0x870 [ 62.999118] [] ? entry_SYSENTER_compat+0x90/0xa2 [ 63.005501] [] __filemap_fdatawrite_range+0x1b3/0x250 [ 63.012435] [] ? replace_page_cache_page+0x620/0x620 [ 63.019172] [] ? ext4_check_all_de+0xf0/0xf0 [ 63.025210] [] filemap_flush+0x23/0x30 [ 63.030725] [] ext4_alloc_da_blocks+0xd9/0x330 [ 63.036929] [] ext4_release_file+0x1ff/0x2e0 [ 63.042966] [] __fput+0x263/0x700 [ 63.048048] [] ____fput+0x15/0x20 [ 63.053125] [] task_work_run+0x10c/0x180 [ 63.058817] [] do_exit+0x9e1/0x27c0 [ 63.064067] [] ? debug_check_no_locks_freed+0x210/0x210 [ 63.071145] [] ? release_task.part.19+0x1210/0x1210 [ 63.077786] [] ? __lock_acquire+0x654/0x4070 [ 63.083816] [] ? kasan_slab_free+0x72/0xc0 [ 63.089673] [] ? recalc_sigpending+0x72/0x90 [ 63.095703] [] do_group_exit+0x111/0x340 [ 63.101391] [] get_signal+0x4cf/0x1450 [ 63.106901] [] do_signal+0x87/0x19f0 [ 63.112239] [] ? __fsnotify_update_child_dentry_flags.part.1+0x300/0x300 [ 63.120700] [] ? selinux_file_permission+0x82/0x470 [ 63.127346] [] ? fsnotify+0x1100/0x1100 [ 63.132939] [] ? setup_sigcontext+0x7d0/0x7d0 [ 63.139056] [] ? rw_verify_area+0xe5/0x2b0 [ 63.144916] [] ? compat_SyS_get_robust_list+0x310/0x310 [ 63.151901] [] ? SyS_write+0x1c0/0x1c0 [ 63.157410] [] ? compat_SyS_ustat+0x30/0x30 [ 63.163462] [] ? exit_to_usermode_loop+0xac/0x120 [ 63.169935] [] exit_to_usermode_loop+0xe1/0x120 [ 63.176228] [] do_fast_syscall_32+0x5c3/0x870 [ 63.182357] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 63.188996] [] entry_SYSENTER_compat+0x90/0xa2 [ 63.195197] Code: ff 48 8b 75 d0 65 48 33 34 25 28 00 00 00 0f 85 50 02 00 00 48 81 c4 a0 01 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 18 fc c1 ff <0f> 0b e8 11 fc c1 ff 8b 95 18 ff ff ff 85 d2 75 7a e8 02 fc c1 [ 63.221931] RIP [] mpage_prepare_extent_to_map+0x7f8/0xa40 [ 63.229298] RSP [ 63.233301] ---[ end trace 76b2e90bb0b0bd5d ]--- [ 63.238046] Kernel panic - not syncing: Fatal exception [ 63.243890] Dumping ftrace buffer: [ 63.247404] (ftrace buffer empty) [ 63.251088] Kernel Offset: disabled [ 63.254688] Rebooting in 86400 seconds..