[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 18.341297] audit: type=1400 audit(1519203468.616:6): avc: denied { map } for pid=4146 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 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.42' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 syzkaller login: [ 24.626456] audit: type=1400 audit(1519203474.902:7): avc: denied { map } for pid=4160 comm="syzkaller854795" path="/root/syzkaller854795778" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported [ 25.000479] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument executing program [ 25.316173] [ 25.317809] ===================================== [ 25.322617] WARNING: bad unlock balance detected! [ 25.327426] 4.16.0-rc2+ #235 Not tainted [ 25.331450] ------------------------------------- [ 25.336257] syzkaller854795/4160 is trying to release lock (rcu_read_lock_bh) at: [ 25.343853] [] hashlimit_mt_common.isra.10+0x1beb/0x2610 [ 25.350830] but there are no more locks to release! [ 25.355809] [ 25.355809] other info that might help us debug this: [ 25.362442] 3 locks held by syzkaller854795/4160: [ 25.367249] #0: (&tfile->napi_mutex){+.+.}, at: [<00000000c4d7073b>] tun_get_user+0xe93/0x3810 [ 25.376144] #1: (rcu_read_lock){....}, at: [<000000009c1b79d2>] netif_receive_skb_internal+0xa2/0x670 [ 25.385646] #2: (rcu_read_lock){....}, at: [<00000000c6d2c538>] ipv6_rcv+0x1446/0x1fa0 [ 25.393844] [ 25.393844] stack backtrace: [ 25.398308] CPU: 0 PID: 4160 Comm: syzkaller854795 Not tainted 4.16.0-rc2+ #235 [ 25.405720] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.415040] Call Trace: [ 25.417599] dump_stack+0x194/0x257 [ 25.421194] ? arch_local_irq_restore+0x53/0x53 [ 25.425833] ? hashlimit_mt_common.isra.10+0x1beb/0x2610 [ 25.431254] print_unlock_imbalance_bug+0x12f/0x140 [ 25.436239] lock_release+0x6fe/0xa40 [ 25.440011] ? hashlimit_mt_common.isra.10+0x1beb/0x2610 [ 25.445432] ? lock_downgrade+0x980/0x980 [ 25.449548] ? lock_release+0xa40/0xa40 [ 25.453490] ? __raw_spin_lock_init+0x1c/0x100 [ 25.458038] ? do_raw_spin_trylock+0x190/0x190 [ 25.462593] hashlimit_mt_common.isra.10+0x1c08/0x2610 [ 25.467837] ? dsthash_find+0x5b0/0x5b0 [ 25.471779] ? __lock_acquire+0x664/0x3e00 [ 25.475979] ? check_noncircular+0x20/0x20 [ 25.480182] ? __put_compound_page+0xc0/0xc0 [ 25.484560] ? lock_release+0xa40/0xa40 [ 25.488503] ? __bfs+0xaa/0x750 [ 25.491752] ? bpf_prog_kallsyms_find+0xbd/0x440 [ 25.496479] ? lock_downgrade+0x980/0x980 [ 25.500594] hashlimit_mt+0x78/0x90 [ 25.504187] ? hashlimit_mt+0x78/0x90 [ 25.507954] ip6t_do_table+0x98d/0x1a30 [ 25.511895] ? is_bpf_text_address+0x7b/0x120 [ 25.516359] ? lock_downgrade+0x980/0x980 [ 25.520477] ? check_noncircular+0x20/0x20 [ 25.524682] ? ip6t_error+0x60/0x60 [ 25.528277] ? find_held_lock+0x35/0x1d0 [ 25.532305] ? check_noncircular+0x20/0x20 [ 25.536508] ? lock_acquire+0x1d5/0x580 [ 25.540451] ? lock_acquire+0x1d5/0x580 [ 25.544393] ? ipv6_rcv+0x1446/0x1fa0 [ 25.548162] ? lock_release+0xa40/0xa40 [ 25.552106] ip6table_raw_hook+0x65/0x80 [ 25.556134] nf_hook_slow+0xba/0x1a0 [ 25.559817] ipv6_rcv+0x1687/0x1fa0 [ 25.563414] ? ip6_rcv_finish+0x8c0/0x8c0 [ 25.567534] ? __lock_acquire+0x664/0x3e00 [ 25.571735] ? ip6_input+0x560/0x560 [ 25.575418] ? ip6_rcv_finish+0x8c0/0x8c0 [ 25.579534] __netif_receive_skb_core+0x1a41/0x3460 [ 25.584520] ? nf_ingress+0x9f0/0x9f0 [ 25.588288] ? __skb_flow_get_ports+0x3d0/0x420 [ 25.592928] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.598086] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.603243] ? print_irqtrace_events+0x270/0x270 [ 25.607965] ? check_noncircular+0x20/0x20 [ 25.612171] ? check_noncircular+0x20/0x20 [ 25.616375] ? lock_downgrade+0x980/0x980 [ 25.620491] ? check_noncircular+0x20/0x20 [ 25.624691] ? lock_release+0xa40/0xa40 [ 25.628631] ? is_bpf_text_address+0xa4/0x120 [ 25.633094] ? find_held_lock+0x35/0x1d0 [ 25.637131] ? print_irqtrace_events+0x270/0x270 [ 25.641856] ? netif_receive_skb_internal+0x1d7/0x670 [ 25.647017] ? lock_downgrade+0x980/0x980 [ 25.651141] ? pvclock_read_flags+0x160/0x160 [ 25.655603] ? mark_held_locks+0xaf/0x100 [ 25.659718] ? lock_acquire+0x1d5/0x580 [ 25.663661] ? lock_acquire+0x1d5/0x580 [ 25.667604] ? netif_receive_skb_internal+0xa2/0x670 [ 25.672677] ? ktime_get_with_offset+0x2c1/0x420 [ 25.677402] ? lock_release+0xa40/0xa40 [ 25.681344] ? do_gettimeofday+0x190/0x190 [ 25.685547] ? lock_release+0xa40/0xa40 [ 25.689489] __netif_receive_skb+0x2c/0x1b0 [ 25.693779] ? __netif_receive_skb+0x2c/0x1b0 [ 25.698243] netif_receive_skb_internal+0x10b/0x670 [ 25.703227] ? dev_cpu_dead+0xb00/0xb00 [ 25.707171] ? net_rx_action+0x1910/0x1910 [ 25.711378] ? eth_type_trans+0x2b2/0x710 [ 25.715493] ? eth_gro_receive+0x820/0x820 [ 25.719697] napi_gro_frags+0x58a/0xaf0 [ 25.723641] ? napi_gro_receive+0x500/0x500 [ 25.727932] ? tun_get_user+0x26f7/0x3810 [ 25.732045] tun_get_user+0x2720/0x3810 [ 25.735989] ? kernel_text_address+0x102/0x140 [ 25.740545] ? tun_build_skb.isra.50+0x1850/0x1850 [ 25.745443] ? xt_table_unlock+0x52/0x60 [ 25.749470] ? lock_downgrade+0x980/0x980 [ 25.753595] ? rawv6_setsockopt+0x4a/0xf0 [ 25.757711] ? SyS_setsockopt+0x189/0x360 [ 25.761829] ? do_syscall_64+0x280/0x940 [ 25.765860] ? tun_get+0x1ab/0x2e0 [ 25.769373] ? lock_release+0xa40/0xa40 [ 25.773314] ? __lock_is_held+0xb6/0x140 [ 25.777342] ? tun_get+0x1d4/0x2e0 [ 25.780850] ? tun_do_read+0x26c0/0x26c0 [ 25.784880] ? __check_object_size+0x8b/0x530 [ 25.789343] ? rcu_note_context_switch+0x710/0x710 [ 25.794242] tun_chr_write_iter+0xbd/0x1c0 [ 25.798443] do_iter_readv_writev+0x55c/0x830 [ 25.802908] ? vfs_dedupe_file_range+0x8f0/0x8f0 [ 25.807633] ? rw_verify_area+0xe5/0x2b0 [ 25.811663] do_iter_write+0x154/0x540 [ 25.815518] ? dup_iter+0x260/0x260 [ 25.819116] ? do_ip6t_set_ctl+0x104/0x5f0 [ 25.823320] vfs_writev+0x18a/0x340 [ 25.826913] ? vfs_iter_write+0xb0/0xb0 [ 25.830859] ? nf_setsockopt+0x93/0xc0 [ 25.834716] ? __fdget_pos+0x130/0x190 [ 25.838573] ? __fdget_raw+0x20/0x20 [ 25.842255] ? sock_common_setsockopt+0x95/0xd0 [ 25.846889] do_writev+0xfc/0x2a0 [ 25.850308] ? do_writev+0xfc/0x2a0 [ 25.853902] ? vfs_writev+0x340/0x340 [ 25.857670] ? mm_fault_error+0x2c0/0x2c0 [ 25.861784] ? move_addr_to_kernel+0x60/0x60 [ 25.866161] ? SyS_readv+0x30/0x30 [ 25.869668] SyS_writev+0x27/0x30 [ 25.873088] do_syscall_64+0x280/0x940 [ 25.876943] ? __do_page_fault+0xc90/0xc90 [ 25.881145] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 25.886651] ? syscall_return_slowpath+0x550/0x550 [ 25.891549] ? syscall_return_slowpath+0x2ac/0x550 [ 25.896448] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 25.901779] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.906588] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 25.911742] RIP: 0033:0x4461f0 [ 25.914899] RSP: 002b:00007fff4be9ee28 EFL