[....] Starting enhanced syslogd: rsyslogd[ 13.267056] audit: type=1400 audit(1539435843.446:4): avc: denied { syslog } for pid=1924 comm="rsyslogd" capability=34 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 [?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.73' (ECDSA) to the list of known hosts. 2018/10/13 13:05:15 parsed 1 programs 2018/10/13 13:05:17 executed programs: 0 2018/10/13 13:05:25 executed programs: 6 syzkaller login: [ 95.454768] syz-executor1 (4779) used greatest stack depth: 23504 bytes left 2018/10/13 13:05:30 executed programs: 133 [ 102.230388] syz-executor2 (5557) used greatest stack depth: 22992 bytes left 2018/10/13 13:05:35 executed programs: 271 2018/10/13 13:05:40 executed programs: 417 INIT: Id "4" respawning too fast: disabled for 5 minutes INIT: Id "5" respawning too fast: disabled for 5 minutes INIT: Id "2" respawning too fast: disabled for 5 minutes INIT: Id "1" respawning too fast: disabled for 5 minutes INIT: Id "6" respawning too fast: disabled for 5 minutes INIT: Id "3" respawning too fast: disabled for 5 minutes 2018/10/13 13:05:45 executed programs: 555 2018/10/13 13:05:50 executed programs: 702 2018/10/13 13:05:55 executed programs: 846 2018/10/13 13:06:00 executed programs: 1001 2018/10/13 13:06:05 executed programs: 1153 2018/10/13 13:06:10 executed programs: 1299 2018/10/13 13:06:15 executed programs: 1453 [ 148.821626] syz-executor4 (11215) used greatest stack depth: 21296 bytes left [ 150.060950] ------------[ cut here ]------------ [ 150.065723] kernel BUG at fs/ext4/inode.c:2462! [ 150.070371] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 150.076223] Modules linked in: [ 150.079517] CPU: 1 PID: 11344 Comm: syz-executor1 Not tainted 4.4.161+ #110 [ 150.086597] task: ffff8801d6c10000 task.stack: ffff8800b7978000 [ 150.092655] RIP: 0010:[] [] mpage_prepare_extent_to_map+0x670/0x8e0 [ 150.102388] RSP: 0018:ffff8800b797f830 EFLAGS: 00010293 [ 150.107811] RAX: ffff8801d6c10000 RBX: ffffea000738db80 RCX: 0000000000000000 [ 150.115055] RDX: 0000000000000000 RSI: ffffffff816400d0 RDI: ffffea000738db90 [ 150.122300] RBP: ffff8800b797f9e8 R08: ffff8801d6c108c8 R09: 0000000000000001 [ 150.129545] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 [ 150.136789] R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8800b797fb30 [ 150.144036] FS: 0000000001b09940(0063) GS:ffff8801db700000(0000) knlGS:0000000000000000 [ 150.152238] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 150.158101] CR2: 000000000072c000 CR3: 00000001d650f000 CR4: 00000000001606b0 [ 150.165350] Stack: [ 150.167489] 1ffff10016f2ff14 ffff8800b797f8c0 ffff8800b797fb38 ffff8800b797fb40 [ 150.175548] 00000000b797f8d8 0007ffffffffffff ffff8801cec433a8 000000090000000c [ 150.183530] 7fffffffffffffff ffff8800b797f900 ffff8800b797fb48 ffffed0016f2ff67 [ 150.191547] Call Trace: [ 150.194119] [] ? mpage_process_page_bufs+0x490/0x490 [ 150.200847] [] ? check_preemption_disabled+0x3b/0x170 [ 150.207661] [] ? check_preemption_disabled+0x3b/0x170 [ 150.214514] [] ext4_writepages+0xd4c/0x2c20 [ 150.220463] [] ? ext4_mark_inode_dirty+0xb80/0xb80 [ 150.227035] [] ? trace_hardirqs_on+0x10/0x10 [ 150.233074] [] ? __lock_acquire+0xa85/0x5f10 [ 150.239125] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 150.246011] [] ? ext4_mark_inode_dirty+0xb80/0xb80 [ 150.252586] [] do_writepages+0xef/0x1d0 [ 150.258203] [] ? ratelimit_handler+0x50/0x50 [ 150.264249] [] ? _raw_spin_unlock_irqrestore+0x5a/0x70 [ 150.271166] [] __filemap_fdatawrite_range+0x1a9/0x250 [ 150.277988] [] ? replace_page_cache_page+0x410/0x410 [ 150.284725] [] ? ext4_check_all_de+0xf0/0xf0 [ 150.290761] [] filemap_flush+0x23/0x30 [ 150.296300] [] ext4_alloc_da_blocks+0x108/0x3c0 [ 150.302612] [] ? ext4_check_all_de+0xf0/0xf0 [ 150.308648] [] ext4_release_file+0x1ff/0x2e0 [ 150.314685] [] __fput+0x235/0x6f0 [ 150.319791] [] ____fput+0x15/0x20 [ 150.324874] [] task_work_run+0x10f/0x190 [ 150.330562] [] exit_to_usermode_loop+0x13d/0x160 [ 150.336973] [] syscall_return_slowpath+0x254/0x2d0 [ 150.343530] [] int_ret_from_sys_call+0x25/0xa3 [ 150.349733] Code: 48 89 df e8 23 45 d7 ff e9 32 ff ff ff e8 49 6e cc ff 48 89 df e8 b1 5e d7 ff e9 fa fd ff ff e8 37 6e cc ff 0f 0b e8 30 6e cc ff <0f> 0b 31 c0 89 85 b0 fe ff ff e8 21 6e cc ff 8b 85 18 ff ff ff [ 150.376754] RIP [] mpage_prepare_extent_to_map+0x670/0x8e0 [ 150.384129] RSP [ 150.389209] ---[ end trace b4bef414d53d053a ]--- [ 150.395761] Kernel panic - not syncing: Fatal exception [ 150.401416] Kernel Offset: disabled [ 150.405024] Rebooting in 86400 seconds..