[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 21.157748] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [ 21.441163] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) [ 21.745376] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.846628] random: nonblocking pool is initialized Warning: Permanently added '10.128.0.30' (ECDSA) to the list of known hosts. 2018/05/19 18:44:01 parsed 1 programs 2018/05/19 18:44:01 executed programs: 0 [ 29.909335] IPVS: Creating netns size=2552 id=1 [ 30.084099] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 30.100104] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 30.182392] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 30.196855] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready [ 30.279359] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 30.293545] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 30.309322] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 30.326975] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 31.058833] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 31.096408] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 31.560732] syz-executor0 (4138) used greatest stack depth: 23616 bytes left 2018/05/19 18:44:06 executed programs: 53 2018/05/19 18:44:11 executed programs: 149 [ 43.673532] ------------[ cut here ]------------ [ 43.678321] kernel BUG at fs/ext4/inode.c:2474! [ 43.682961] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 43.688772] Dumping ftrace buffer: [ 43.692282] (ftrace buffer empty) [ 43.695963] Modules linked in: [ 43.699244] CPU: 1 PID: 5043 Comm: syz-executor0 Not tainted 4.4.132-g4f75c34 #42 [ 43.706875] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.716200] task: ffff8800afc68000 task.stack: ffff8800b1df8000 [ 43.722225] RIP: 0010:[] [] mpage_prepare_extent_to_map+0x74f/0x970 [ 43.731933] RSP: 0018:ffff8800b1dff3d0 EFLAGS: 00010293 [ 43.737359] RAX: ffff8800afc68000 RBX: ffffea0002996980 RCX: 0000000000000000 [ 43.744601] RDX: 0000000000000000 RSI: ffffffff816d736f RDI: ffffea0002996988 [ 43.751842] RBP: ffff8800b1dff598 R08: ffff8800afc68928 R09: 0000000000000001 [ 43.759086] R10: 0000000000000000 R11: ffff8800afc68000 R12: 0000000000000001 [ 43.766328] R13: 0000000000000000 R14: ffff8800b1dff6e0 R15: dffffc0000000000 [ 43.773569] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 43.781765] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 43.787617] CR2: 00000000024b6ef8 CR3: 000000000440c000 CR4: 00000000001606f0 [ 43.794859] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 43.802100] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 43.809340] Stack: [ 43.811945] ffff8800b1dff4f8 1ffff100163bfe8a ffff8800b1dff6e8 ffff8800b1dff470 [ 43.819919] ffff8800b1dff6f0 00000000d3adbc68 ffff8800adcc33d8 000000090000000c [ 43.827891] 7fffffffffffffff ffff8800b1dff4b0 ffff8800b1dff6f8 ffffea0002996990 [ 43.835866] Call Trace: [ 43.838432] [] ? ext4_journalled_zero_new_buffers+0x350/0x350 [ 43.845939] [] ? __lock_is_held+0xa2/0xf0 [ 43.851708] [] ? __lock_is_held+0xa2/0xf0 [ 43.857478] [] ext4_writepages+0xbb0/0x2c80 [ 43.863421] [] ? __module_text_address+0x13/0x140 [ 43.869883] [] ? __module_text_address+0x13/0x140 [ 43.876346] [] ? ext4_mark_inode_dirty+0xb80/0xb80 [ 43.882895] [] ? print_context_stack+0x4b/0xd0 [ 43.889109] [] ? dump_trace+0x184/0x360 [ 43.894710] [] ? depot_save_stack+0x1c9/0x610 [ 43.900835] [] ? ext4_mark_inode_dirty+0xb80/0xb80 [ 43.907387] [] do_writepages+0xef/0x1d0 [ 43.912979] [] ? ratelimit_handler+0x50/0x50 [ 43.919006] [] ? do_exit+0x9bf/0x26b0 [ 43.924427] [] ? do_group_exit+0x111/0x330 [ 43.930281] [] ? get_signal+0x4ec/0x14b0 [ 43.935962] [] ? do_signal+0x8b/0x1d30 [ 43.941470] [] ? exit_to_usermode_loop+0x11a/0x160 [ 43.948020] [] ? do_fast_syscall_32+0x620/0x8b0 [ 43.954313] [] ? sysenter_flags_fixed+0xd/0x17 [ 43.960519] [] __filemap_fdatawrite_range+0x1b3/0x250 [ 43.967327] [] ? replace_page_cache_page+0x440/0x440 [ 43.974056] [] ? ext4_check_all_de+0xf0/0xf0 [ 43.980087] [] filemap_flush+0x23/0x30 [ 43.985596] [] ext4_alloc_da_blocks+0x108/0x3c0 [ 43.991895] [] ? ext4_check_all_de+0xf0/0xf0 [ 43.997922] [] ext4_release_file+0x1ff/0x2e0 [ 44.003961] [] __fput+0x235/0x6f0 [ 44.009038] [] ____fput+0x15/0x20 [ 44.014122] [] task_work_run+0x10f/0x190 [ 44.019812] [] do_exit+0x9e5/0x26b0 [ 44.025060] [] ? release_task.part.17+0x1200/0x1200 [ 44.031698] [] ? debug_check_no_locks_freed+0x210/0x210 [ 44.039040] [] ? recalc_sigpending+0x76/0xa0 [ 44.045083] [] do_group_exit+0x111/0x330 [ 44.050788] [] get_signal+0x4ec/0x14b0 [ 44.056321] [] ? fsnotify+0x866/0x10c0 [ 44.061854] [] do_signal+0x8b/0x1d30 [ 44.067213] [] ? __fsnotify_update_child_dentry_flags.part.2+0x300/0x300 [ 44.075687] [] ? selinux_file_permission+0x2f2/0x450 [ 44.082418] [] ? setup_sigcontext+0x780/0x780 [ 44.088540] [] ? rw_verify_area+0x100/0x300 [ 44.094483] [] ? compat_SyS_futex+0x1e1/0x2f0 [ 44.100603] [] ? compat_SyS_get_robust_list+0x310/0x310 [ 44.107585] [] ? exit_to_usermode_loop+0xe4/0x160 [ 44.114054] [] exit_to_usermode_loop+0x11a/0x160 [ 44.120436] [] do_fast_syscall_32+0x620/0x8b0 [ 44.126555] [] sysenter_flags_fixed+0xd/0x17 [ 44.132582] Code: ff 48 8b 75 d0 65 48 33 34 25 28 00 00 00 0f 85 2e 02 00 00 48 81 c4 a0 01 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 71 9e c7 ff <0f> 0b e8 6a 9e c7 ff 8b 95 18 ff ff ff 85 d2 75 7f e8 5b 9e c7 [ 44.159293] RIP [] mpage_prepare_extent_to_map+0x74f/0x970 [ 44.166660] RSP [ 44.170355] ---[ end trace 0e8733d07c29195a ]--- [ 44.175724] Kernel panic - not syncing: Fatal exception [ 44.181440] Dumping ftrace buffer: [ 44.184958] (ftrace buffer empty) [ 44.188643] Kernel Offset: disabled [ 44.192241] Rebooting in 86400 seconds..