[ 36.846992][ T26] audit: type=1800 audit(1552926256.490:27): pid=7635 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [ 36.870702][ T26] audit: type=1800 audit(1552926256.490:28): pid=7635 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="ssh" dev="sda1" ino=2417 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 37.568158][ T26] audit: type=1800 audit(1552926257.290:29): pid=7635 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 37.593803][ T26] audit: type=1800 audit(1552926257.290:30): pid=7635 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.121' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 45.146886][ T7788] [ 45.149422][ T7788] ============================= [ 45.154356][ T7788] WARNING: suspicious RCU usage [ 45.159214][ T7788] 5.1.0-rc1-next-20190318 #5 Not tainted [ 45.164925][ T7788] ----------------------------- [ 45.169778][ T7788] net/xfrm/xfrm_user.c:1080 suspicious rcu_dereference_check() usage! [ 45.178157][ T7788] [ 45.178157][ T7788] other info that might help us debug this: [ 45.178157][ T7788] [ 45.188461][ T7788] [ 45.188461][ T7788] rcu_scheduler_active = 2, debug_locks = 1 [ 45.196566][ T7788] 1 lock held by syz-executor615/7788: [ 45.202006][ T7788] #0: 00000000d9f69f58 (&net->xfrm.xfrm_cfg_mutex){+.+.}, at: xfrm_netlink_rcv+0x61/0x90 [ 45.211957][ T7788] [ 45.211957][ T7788] stack backtrace: [ 45.217880][ T7788] CPU: 1 PID: 7788 Comm: syz-executor615 Not tainted 5.1.0-rc1-next-20190318 #5 [ 45.226874][ T7788] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.236950][ T7788] Call Trace: [ 45.240228][ T7788] dump_stack+0x172/0x1f0 [ 45.244541][ T7788] lockdep_rcu_suspicious+0x153/0x15d [ 45.249894][ T7788] xfrm_get_spdinfo+0x923/0xb20 [ 45.254726][ T7788] ? xfrm_send_state_notify+0x1b90/0x1b90 [ 45.260424][ T7788] ? audit_add_tree_rule+0x520/0xbc0 [ 45.265692][ T7788] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 45.271913][ T7788] ? __nla_parse+0x12a/0x340 [ 45.276482][ T7788] ? nla_parse+0x45/0x60 [ 45.280703][ T7788] ? xfrm_send_state_notify+0x1b90/0x1b90 [ 45.286405][ T7788] xfrm_user_rcv_msg+0x458/0x770 [ 45.291339][ T7788] ? xfrm_dump_sa_done+0xf0/0xf0 [ 45.296262][ T7788] ? mark_held_locks+0xf0/0xf0 [ 45.301026][ T7788] ? save_stack+0xa9/0xd0 [ 45.305376][ T7788] ? __mutex_lock+0x3cd/0x1310 [ 45.310125][ T7788] ? xfrm_netlink_rcv+0x61/0x90 [ 45.314967][ T7788] netlink_rcv_skb+0x17a/0x460 [ 45.319712][ T7788] ? xfrm_dump_sa_done+0xf0/0xf0 [ 45.324630][ T7788] ? netlink_ack+0xb50/0xb50 [ 45.329234][ T7788] xfrm_netlink_rcv+0x70/0x90 [ 45.333895][ T7788] netlink_unicast+0x536/0x720 [ 45.338638][ T7788] ? netlink_attachskb+0x770/0x770 [ 45.343726][ T7788] ? _copy_from_iter_full+0x259/0x8f0 [ 45.349090][ T7788] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 45.354788][ T7788] ? __check_object_size+0x3d/0x42f [ 45.359965][ T7788] netlink_sendmsg+0x8ae/0xd70 [ 45.364709][ T7788] ? netlink_unicast+0x720/0x720 [ 45.369716][ T7788] ? aa_sock_msg_perm.isra.0+0xba/0x170 [ 45.375245][ T7788] ? apparmor_socket_sendmsg+0x2a/0x30 [ 45.380679][ T7788] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 45.386902][ T7788] ? security_socket_sendmsg+0x93/0xc0 [ 45.392352][ T7788] ? netlink_unicast+0x720/0x720 [ 45.397449][ T7788] sock_sendmsg+0xdd/0x130 [ 45.401846][ T7788] ___sys_sendmsg+0x806/0x930 [ 45.406503][ T7788] ? copy_msghdr_from_user+0x430/0x430 [ 45.411952][ T7788] ? __thp_get_unmapped_area+0x190/0x190 [ 45.417570][ T7788] ? __lock_acquire+0x548/0x3fb0 [ 45.422506][ T7788] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 45.428858][ T7788] ? __handle_mm_fault+0x7cd/0x3ec0 [ 45.434052][ T7788] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 45.440287][ T7788] ? __fget_light+0x1a9/0x230 [ 45.444943][ T7788] ? __fdget+0x1b/0x20 [ 45.448986][ T7788] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 45.455215][ T7788] __sys_sendmsg+0x105/0x1d0 [ 45.459793][ T7788] ? __ia32_sys_shutdown+0x80/0x80 [ 45.464895][ T7788] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 45.470346][ T7788] ? do_syscall_64+0x26/0x610 [ 45.475005][ T7788] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 45.481050][ T7788] ? do_syscall_64+0x26/0x610 [ 45.485730][ T7788] __x64_sys_sendmsg+0x78/0xb0 [ 45.490479][ T7788] do_syscall_64+0x103/0x610 [ 45.495055][ T7788] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 45.500941][ T7788] RIP: 0033:0x4401d9 [ 45.504837][ T7788] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 45.525812][ T7788] RSP: 002b:00007ffc72c76dd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 45.534214][ T7788] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401d9 [ 45.542164][ T7788] RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000