[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 34.855565] random: sshd: uninitialized urandom read (32 bytes read) [ 35.277248] kauditd_printk_skb: 10 callbacks suppressed [ 35.277257] audit: type=1400 audit(1570106647.898:35): avc: denied { map } for pid=6938 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 [ 35.333430] random: sshd: uninitialized urandom read (32 bytes read) [ 35.878442] random: sshd: uninitialized urandom read (32 bytes read) [ 36.072142] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.4' (ECDSA) to the list of known hosts. [ 41.535103] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 41.654975] audit: type=1400 audit(1570106654.278:36): avc: denied { map } for pid=6950 comm="syz-executor279" path="/root/syz-executor279189108" dev="sda1" ino=16483 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 41.661146] [ 41.681972] audit: type=1400 audit(1570106654.278:37): avc: denied { create } for pid=6950 comm="syz-executor279" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1 [ 41.683099] ============================= [ 41.707659] audit: type=1400 audit(1570106654.278:38): avc: denied { write } for pid=6950 comm="syz-executor279" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1 [ 41.712062] WARNING: suspicious RCU usage [ 41.735878] audit: type=1400 audit(1570106654.278:39): avc: denied { read } for pid=6950 comm="syz-executor279" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1 [ 41.739954] 4.14.146 #0 Not tainted [ 41.767847] ----------------------------- [ 41.772045] net/tipc/bearer.c:177 suspicious rcu_dereference_protected() usage! [ 41.779578] [ 41.779578] other info that might help us debug this: [ 41.779578] [ 41.788313] [ 41.788313] rcu_scheduler_active = 2, debug_locks = 1 [ 41.795067] 2 locks held by syz-executor279/6950: [ 41.799903] #0: (cb_lock){++++}, at: [] genl_rcv+0x1a/0x40 [ 41.807419] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x119/0x150 [ 41.815638] [ 41.815638] stack backtrace: [ 41.820168] CPU: 1 PID: 6950 Comm: syz-executor279 Not tainted 4.14.146 #0 [ 41.827168] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.836504] Call Trace: [ 41.839082] dump_stack+0x138/0x197 [ 41.842698] lockdep_rcu_suspicious+0x153/0x15d [ 41.847351] tipc_bearer_find+0x20a/0x300 [ 41.851478] tipc_nl_compat_link_set+0x433/0xbf0 [ 41.856218] tipc_nl_compat_doit+0x1a2/0x550 [ 41.860626] ? security_capable+0x8e/0xc0 [ 41.864753] ? tipc_nl_compat_link_stat_dump+0x2080/0x2080 [ 41.870364] ? ns_capable_common+0x12c/0x160 [ 41.874747] ? ns_capable+0x23/0x30 [ 41.878354] ? __netlink_ns_capable+0xe2/0x130 [ 41.882916] tipc_nl_compat_recv+0x9ec/0xb20 [ 41.887335] ? is_bpf_text_address+0xa6/0x120 [ 41.891807] ? tipc_nl_compat_doit+0x550/0x550 [ 41.896364] ? tipc_nl_node_dump+0xc90/0xc90 [ 41.900751] ? tipc_nl_compat_bearer_enable+0x570/0x570 [ 41.906093] ? lock_acquire+0x16f/0x430 [ 41.910044] ? genl_rcv_msg+0x119/0x150 [ 41.913995] ? genl_rcv_msg+0x119/0x150 [ 41.917950] genl_family_rcv_msg+0x614/0xc30 [ 41.922339] ? genl_unregister_family+0x6a0/0x6a0 [ 41.927173] genl_rcv_msg+0xb4/0x150 [ 41.930864] netlink_rcv_skb+0x14f/0x3c0 [ 41.934902] ? genl_family_rcv_msg+0xc30/0xc30 [ 41.939461] ? netlink_ack+0x9a0/0x9a0 [ 41.943327] ? genl_rcv+0x1a/0x40 [ 41.946765] genl_rcv+0x29/0x40 [ 41.950021] netlink_unicast+0x45d/0x640 [ 41.954064] ? netlink_attachskb+0x6a0/0x6a0 [ 41.958452] ? security_netlink_send+0x81/0xb0 [ 41.963013] netlink_sendmsg+0x7c4/0xc60 [ 41.967055] ? netlink_unicast+0x640/0x640 [ 41.971271] ? security_socket_sendmsg+0x89/0xb0 [ 41.976018] ? netlink_unicast+0x640/0x640 [ 41.980238] sock_sendmsg+0xce/0x110 [ 41.983931] ___sys_sendmsg+0x70a/0x840 [ 41.987895] ? copy_msghdr_from_user+0x3f0/0x3f0 [ 41.992627] ? __lock_acquire+0x5f7/0x4620 [ 41.996837] ? save_trace+0x290/0x290 [ 42.000621] ? trace_hardirqs_on+0x10/0x10 [ 42.004836] ? save_trace+0x290/0x290 [ 42.008613] ? lock_downgrade+0x6e0/0x6e0 [ 42.012738] ? task_work_run+0xf0/0x190 [ 42.016702] ? __fget_light+0x172/0x1f0 [ 42.020656] ? __fdget+0x1b/0x20 [ 42.024000] ? sockfd_lookup_light+0xb4/0x160 [ 42.028489] __sys_sendmsg+0xb9/0x140 [ 42.032271] ? SyS_shutdown+0x170/0x170 [ 42.036239] ? trace_hardirqs_on_caller+0x400/0x590 [ 42.041411] SyS_sendmsg+0x2d/0x50 [ 42.044928] ? __sys_sendmsg+0x140/0x140 [ 42.048969] do_syscall_64+0x1e8/0x640 [ 42.052835] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 42.057659] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 42.062825] RIP: 0033:0x444229 [ 42.065990] RSP: 002b:00007ffdfd967bd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 42.073672] RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000444229 [ 42.080920] RDX: 0000000000000000 RSI: 00000000200002c0 RDI: 0000000000000003 [ 42.088179] RBP: 00000000006ce018 R08: 0000000000000000 R09: 00000000004002e0 [ 42.095430] R10: 0000000000001800 R11: 0000000000000246 R12: 0000000000401ed0 [ 42.102681] R13: 0000000000401f60 R14: 0000000000