[....] Starting enhanced syslogd: rsyslogd[ 15.500319] audit: type=1400 audit(1519078933.055:5): avc: denied { syslog } for pid=3997 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 syzkaller login: [ 18.635092] audit: type=1400 audit(1519078936.189:6): avc: denied { map } for pid=4135 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Warning: Permanently added '10.128.0.15' (ECDSA) to the list of known hosts. [ 27.972060] audit: type=1400 audit(1519078945.526:7): avc: denied { map } for pid=4150 comm="syz-execprog" path="/root/syz-execprog" dev="sda1" ino=16479 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 2018/02/19 22:22:25 parsed 1 programs 2018/02/19 22:22:25 executed programs: 0 [ 28.217323] audit: type=1400 audit(1519078945.771:8): avc: denied { map } for pid=4150 comm="syz-execprog" path="/root/syzkaller-shm936304487" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:file_t:s0 tclass=file permissive=1 [ 28.225268] IPVS: ftp: loaded support on port[0] = 21 [ 28.443405] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 28.758342] [ 28.759982] ===================================== [ 28.764790] WARNING: bad unlock balance detected! [ 28.769598] 4.16.0-rc2+ #320 Not tainted [ 28.773625] ------------------------------------- [ 28.778434] syz-executor0/4285 is trying to release lock (rcu_read_lock_bh) at: [ 28.785860] [] hashlimit_mt_common.isra.10+0x1beb/0x2610 [ 28.792846] but there are no more locks to release! [ 28.797838] [ 28.797838] other info that might help us debug this: [ 28.804472] 3 locks held by syz-executor0/4285: [ 28.809104] #0: (&tfile->napi_mutex){+.+.}, at: [<00000000a3629f2b>] tun_get_user+0xe6c/0x3940 [ 28.818002] #1: (rcu_read_lock){....}, at: [<00000000481a7888>] netif_receive_skb_internal+0xa2/0x670 [ 28.827513] #2: (rcu_read_lock){....}, at: [<0000000081b19393>] ipv6_rcv+0x1446/0x1fa0 [ 28.835730] [ 28.835730] stack backtrace: [ 28.840196] CPU: 1 PID: 4285 Comm: syz-executor0 Not tainted 4.16.0-rc2+ #320 [ 28.847434] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.856758] Call Trace: [ 28.859319] dump_stack+0x194/0x257 [ 28.862915] ? arch_local_irq_restore+0x53/0x53 [ 28.867557] ? hashlimit_mt_common.isra.10+0x1beb/0x2610 [ 28.872978] print_unlock_imbalance_bug+0x12f/0x140 [ 28.877963] lock_release+0x6fe/0xa40 [ 28.881736] ? hashlimit_mt_common.isra.10+0x1beb/0x2610 [ 28.887156] ? lock_downgrade+0x980/0x980 [ 28.891271] ? lock_release+0xa40/0xa40 [ 28.895212] ? __raw_spin_lock_init+0x1c/0x100 [ 28.899761] ? do_raw_spin_trylock+0x190/0x190 [ 28.904312] hashlimit_mt_common.isra.10+0x1c08/0x2610 [ 28.909558] ? dsthash_find+0x5b0/0x5b0 [ 28.913506] ? __lock_acquire+0x664/0x3e00 [ 28.917716] ? get_page_from_freelist+0x2d7f/0x52d0 [ 28.922700] ? get_page_from_freelist+0x2deb/0x52d0 [ 28.927688] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 28.932845] ? lock_release+0xa40/0xa40 [ 28.936787] ? __bfs+0xaa/0x750 [ 28.940037] ? bpf_prog_kallsyms_find+0xbd/0x440 [ 28.944761] ? lock_downgrade+0x980/0x980 [ 28.948880] hashlimit_mt+0x78/0x90 [ 28.952483] ? hashlimit_mt+0x78/0x90 [ 28.956250] ip6t_do_table+0x98d/0x1a30 [ 28.960191] ? is_bpf_text_address+0x7b/0x120 [ 28.964660] ? lock_downgrade+0x980/0x980 [ 28.968774] ? __bfs+0xaa/0x750 [ 28.972021] ? check_noncircular+0x20/0x20 [ 28.976228] ? ip6t_error+0x60/0x60 [ 28.979823] ? find_held_lock+0x35/0x1d0 [ 28.983850] ? check_noncircular+0x20/0x20 [ 28.988053] ? lock_acquire+0x1d5/0x580 [ 28.991994] ? lock_acquire+0x1d5/0x580 [ 28.995938] ? ipv6_rcv+0x1446/0x1fa0 [ 28.999710] ? lock_release+0xa40/0xa40 [ 29.003653] ip6table_raw_hook+0x65/0x80 [ 29.007682] nf_hook_slow+0xba/0x1a0 [ 29.011364] ipv6_rcv+0x1687/0x1fa0 [ 29.014960] ? ip6_rcv_finish+0x8c0/0x8c0 [ 29.019079] ? __lock_acquire+0x664/0x3e00 [ 29.023283] ? ip6_input+0x560/0x560 [ 29.026963] ? ip6_rcv_finish+0x8c0/0x8c0 [ 29.031078] __netif_receive_skb_core+0x1a41/0x3460 [ 29.036065] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 29.041227] ? nf_ingress+0x9f0/0x9f0 [ 29.045001] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 29.050160] ? do_csum+0x288/0x360 [ 29.053669] ? csum_partial+0x21/0x30 [ 29.057438] ? csum_partial_ext+0x25/0x30 [ 29.061553] ? check_noncircular+0x20/0x20 [ 29.065753] ? __skb_checksum+0x4a9/0x7e0 [ 29.069869] ? find_held_lock+0x35/0x1d0 [ 29.073900] ? print_irqtrace_events+0x270/0x270 [ 29.078623] ? lock_downgrade+0x980/0x980 [ 29.082746] ? pvclock_read_flags+0x160/0x160 [ 29.087213] ? mark_held_locks+0xaf/0x100 [ 29.091329] ? lock_acquire+0x1d5/0x580 [ 29.095276] ? lock_acquire+0x1d5/0x580 [ 29.099222] ? netif_receive_skb_internal+0xa2/0x670 [ 29.104297] ? ktime_get_with_offset+0x2c1/0x420 [ 29.109025] ? lock_release+0xa40/0xa40 [ 29.112970] ? do_gettimeofday+0x190/0x190 [ 29.117174] ? lock_release+0xa40/0xa40 [ 29.121118] __netif_receive_skb+0x2c/0x1b0 [ 29.125404] ? __netif_receive_skb+0x2c/0x1b0 [ 29.129866] netif_receive_skb_internal+0x10b/0x670 [ 29.134849] ? dev_cpu_dead+0xb00/0xb00 [ 29.138794] ? net_rx_action+0x1910/0x1910 [ 29.142995] ? eth_type_trans+0x2b2/0x710 [ 29.147109] ? eth_gro_receive+0x820/0x820 [ 29.151312] napi_gro_frags+0x58a/0xaf0 [ 29.155253] ? napi_gro_receive+0x500/0x500 [ 29.159545] ? tun_get_user+0x2737/0x3940 [ 29.163658] tun_get_user+0x2760/0x3940 [ 29.167601] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 29.172774] ? do_huge_pmd_anonymous_page+0xab1/0x1b00 [ 29.178028] ? tun_build_skb.isra.50+0x1850/0x1850 [ 29.182931] ? clear_huge_page+0x309/0x730 [ 29.187149] ? _raw_spin_unlock+0x22/0x30 [ 29.191278] ? mmdrop+0x18/0x30 [ 29.194534] ? drop_futex_key_refs.isra.13+0x63/0xa0 [ 29.199614] ? find_held_lock+0x35/0x1d0 [ 29.203645] ? tun_get+0x1ab/0x2e0 [ 29.207154] ? lock_release+0xa40/0xa40 [ 29.211095] ? __lock_is_held+0xb6/0x140 [ 29.215124] ? tun_get+0x1d4/0x2e0 [ 29.218629] ? tun_do_read+0x26c0/0x26c0 [ 29.222657] ? __check_object_size+0x8b/0x530 [ 29.227124] ? rcu_note_context_switch+0x710/0x710 [ 29.232024] tun_chr_write_iter+0xbd/0x1c0 [ 29.236228] do_iter_readv_writev+0x55c/0x830 [ 29.240691] ? vfs_dedupe_file_range+0x8f0/0x8f0 [ 29.245415] ? rw_verify_area+0xe5/0x2b0 [ 29.249456] do_iter_write+0x154/0x540 [ 29.253310] ? dup_iter+0x260/0x260 [ 29.256906] vfs_writev+0x18a/0x340 [ 29.260504] ? vfs_iter_write+0xb0/0xb0 [ 29.264453] ? __fdget_pos+0x130/0x190 [ 29.268309] ? __handle_mm_fault+0x3ce0/0x3ce0 [ 29.272857] ? __fdget_raw+0x20/0x20 [ 29.276537] do_writev+0xfc/0x2a0 [ 29.279956] ? do_writev+0xfc/0x2a0 [ 29.283550] ? vfs_writev+0x340/0x340 [ 29.287319] ? mm_fault_error+0x2c0/0x2c0 [ 29.291438] ? move_addr_to_kernel+0x60/0x60 [ 29.295817] ? SyS_readv+0x30/0x30 [ 29.299325] SyS_writev+0x27/0x30 [ 29.302747] do_syscall_64+0x280/0x940 [ 29.306600] ? __do_page_fault+0xc90/0xc90 [ 29.310801] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 29.315533] ? syscall_return_slowpath+0x550/0x550 [ 29.320431] ? syscall_return_slowpath+0x2ac/0x550 [ 29.325328] ? prepare_exit_to_usermode+0x350/0x350 [ 29.330318] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 29.335656] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.340467] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 29.345625] RIP: 0033:0x453c60 [ 29.348781] RSP: 002b:00007fff31d39658 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 [ 29.356455] RAX: ffffffffffffffda RBX: 00000000000