[....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 14.873241] 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: [ 20.199641] random: sshd: uninitialized urandom read (32 bytes read) [ 20.902239] random: sshd: uninitialized urandom read (32 bytes read) [ 21.676852] random: sshd: uninitialized urandom read (32 bytes read) [ 87.858014] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.9' (ECDSA) to the list of known hosts. [ 93.358894] random: sshd: uninitialized urandom read (32 bytes read) 2018/05/19 18:41:15 parsed 1 programs 2018/05/19 18:41:15 executed programs: 0 [ 93.968962] IPVS: Creating netns size=2536 id=1 [ 94.066633] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 94.079734] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 94.126796] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 94.140311] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 94.176979] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 94.188758] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 94.202755] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 94.225030] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 94.595070] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 94.622997] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 94.629336] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 94.636558] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 94.951495] syz-executor0 (4101) used greatest stack depth: 23384 bytes left 2018/05/19 18:41:21 executed programs: 80 2018/05/19 18:41:26 executed programs: 177 [ 106.347301] random: crng init done 2018/05/19 18:41:31 executed programs: 278 [ 109.447771] ------------[ cut here ]------------ [ 109.452570] kernel BUG at fs/ext4/inode.c:2630! [ 109.457341] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 109.462688] Dumping ftrace buffer: [ 109.466210] (ftrace buffer empty) [ 109.469919] Modules linked in: [ 109.473248] CPU: 1 PID: 5263 Comm: syz-executor0 Not tainted 4.9.100-ge14d1a3 #31 [ 109.480858] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 109.490221] task: ffff8801b57e9800 task.stack: ffff8801d8350000 [ 109.496253] RIP: 0010:[] [] mpage_prepare_extent_to_map+0x7f8/0xa40 [ 109.506320] RSP: 0018:ffff8801d83573b0 EFLAGS: 00010293 [ 109.511745] RAX: ffff8801b57e9800 RBX: ffffea0006e04100 RCX: 0000000000000000 [ 109.519251] RDX: 0000000000000000 RSI: ffffffff8173cde8 RDI: ffffea0006e04108 [ 109.526493] RBP: ffff8801d8357578 R08: ffff8801b57ea138 R09: 0000000000000001 [ 109.533748] R10: 0000000000000000 R11: 1ffff10036afd422 R12: 0000000000000008 [ 109.541006] R13: 0000000000000000 R14: ffff8801d83576e0 R15: dffffc0000000000 [ 109.548699] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 109.556909] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 109.562778] CR2: 000000000814b021 CR3: 000000000461e000 CR4: 00000000001606f0 [ 109.570034] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 109.577278] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 109.584545] Stack: [ 109.586678] 1ffff1003b06ae86 ffff8801d83576e8 ffff8801d8357450 ffff8801d83576f0 [ 109.594680] 00000000b57ea0c0 ffff8801b9da4cc0 000000020000000c 7fffffffffffffff [ 109.602714] ffff8801d8357490 ffff8801d83576f8 ffffea0006e04110 ffffed003b06aedd [ 109.610712] Call Trace: [ 109.613277] [] ? ext4_journalled_zero_new_buffers+0x3a0/0x3a0 [ 109.620985] [] ? __lock_is_held+0xa2/0xf0 [ 109.626783] [] ? __lock_is_held+0xa2/0xf0 [ 109.632579] [] ext4_writepages+0xdb9/0x2e50 [ 109.638576] [] ? do_writepages+0xef/0x1d0 [ 109.644388] [] ? __unwind_start+0x14d/0x3c0 [ 109.650352] [] ? unwind_next_frame+0x86/0xe0 [ 109.656409] [] ? ext4_mark_inode_dirty+0xb40/0xb40 [ 109.662996] [] ? __unwind_start+0x14d/0x3c0 [ 109.668946] [] ? depot_save_stack+0x132/0x460 [ 109.675069] [] ? ext4_mark_inode_dirty+0xb40/0xb40 [ 109.681629] [] do_writepages+0xef/0x1d0 [ 109.687239] [] ? page_writeback_cpu_online+0x20/0x20 [ 109.693989] [] ? exit_fs+0xe9/0x120 [ 109.699242] [] ? do_exit+0x9bb/0x27c0 [ 109.704680] [] ? do_group_exit+0x111/0x340 [ 109.710541] [] ? get_signal+0x4cf/0x1450 [ 109.716233] [] ? do_signal+0x87/0x19f0 [ 109.721744] [] ? exit_to_usermode_loop+0xe1/0x120 [ 109.728214] [] ? do_fast_syscall_32+0x5c3/0x870 [ 109.734684] [] ? entry_SYSENTER_compat+0x90/0xa2 [ 109.741068] [] __filemap_fdatawrite_range+0x1b3/0x250 [ 109.747886] [] ? replace_page_cache_page+0x620/0x620 [ 109.754629] [] ? ext4_check_all_de+0xf0/0xf0 [ 109.760667] [] filemap_flush+0x23/0x30 [ 109.766194] [] ext4_alloc_da_blocks+0xd9/0x330 [ 109.772415] [] ext4_release_file+0x1ff/0x2e0 [ 109.778460] [] __fput+0x263/0x700 [ 109.783534] [] ____fput+0x15/0x20 [ 109.788633] [] task_work_run+0x10c/0x180 [ 109.794318] [] do_exit+0x9e1/0x27c0 [ 109.799573] [] ? debug_check_no_locks_freed+0x210/0x210 [ 109.806570] [] ? release_task.part.19+0x1210/0x1210 [ 109.813219] [] ? __lock_acquire+0x654/0x4070 [ 109.819266] [] ? kasan_slab_free+0x72/0xc0 [ 109.825130] [] ? recalc_sigpending+0x72/0x90 [ 109.831598] [] do_group_exit+0x111/0x340 [ 109.837289] [] get_signal+0x4cf/0x1450 [ 109.842812] [] do_signal+0x87/0x19f0 [ 109.848154] [] ? __fsnotify_update_child_dentry_flags.part.1+0x300/0x300 [ 109.856704] [] ? selinux_file_permission+0x82/0x470 [ 109.863355] [] ? fsnotify+0x1100/0x1100 [ 109.868960] [] ? setup_sigcontext+0x7d0/0x7d0 [ 109.875081] [] ? rw_verify_area+0xe5/0x2b0 [ 109.880942] [] ? compat_SyS_get_robust_list+0x310/0x310 [ 109.887935] [] ? SyS_write+0x1c0/0x1c0 [ 109.893461] [] ? compat_SyS_ustat+0x30/0x30 [ 109.899420] [] ? exit_to_usermode_loop+0xac/0x120 [ 109.905896] [] exit_to_usermode_loop+0xe1/0x120 [ 109.912190] [] do_fast_syscall_32+0x5c3/0x870 [ 109.918315] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 109.924957] [] entry_SYSENTER_compat+0x90/0xa2 [ 109.931159] 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 [ 109.957999] RIP [] mpage_prepare_extent_to_map+0x7f8/0xa40 [ 109.965549] RSP [ 109.969360] ---[ end trace c2ad521b45ab8c2c ]--- [ 109.974094] Kernel panic - not syncing: Fatal exception [ 109.979872] Dumping ftrace buffer: [ 109.983395] (ftrace buffer empty) [ 109.987082] Kernel Offset: disabled [ 109.990682] Rebooting in 86400 seconds..