Warning: Permanently added '10.128.0.51' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 34.397813] audit: type=1400 audit(1589391169.490:8): avc: denied { execmem } for pid=6326 comm="syz-executor430" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 34.402691] [ 34.419659] ============================= [ 34.423858] WARNING: suspicious RCU usage [ 34.428001] 4.14.180-syzkaller #0 Not tainted [ 34.432471] ----------------------------- [ 34.436891] net/tipc/bearer.c:177 suspicious rcu_dereference_protected() usage! [ 34.444520] [ 34.444520] other info that might help us debug this: [ 34.444520] [ 34.452661] [ 34.452661] rcu_scheduler_active = 2, debug_locks = 1 [ 34.459388] 2 locks held by syz-executor430/6326: [ 34.464291] #0: (cb_lock){++++}, at: [] genl_rcv+0x15/0x40 [ 34.471673] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x112/0x140 [ 34.479909] [ 34.479909] stack backtrace: [ 34.484471] CPU: 1 PID: 6326 Comm: syz-executor430 Not tainted 4.14.180-syzkaller #0 [ 34.492354] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.501686] Call Trace: [ 34.504253] dump_stack+0x13e/0x194 [ 34.507855] tipc_bearer_find+0x1ff/0x2f0 [ 34.511981] tipc_nl_compat_link_set+0x41f/0xbc0 [ 34.516714] tipc_nl_compat_doit+0x18d/0x510 [ 34.521097] ? tipc_nl_compat_link_stat_dump+0x1c40/0x1c40 [ 34.526711] ? cap_capable+0x1c4/0x230 [ 34.530592] ? security_capable+0x88/0xb0 [ 34.534734] ? ns_capable_common+0x127/0x150 [ 34.539123] tipc_nl_compat_recv+0x95c/0xa10 [ 34.543527] ? tipc_nl_compat_doit+0x510/0x510 [ 34.548089] ? tipc_nl_node_dump+0xc60/0xc60 [ 34.552487] ? tipc_nl_compat_bearer_enable+0x560/0x560 [ 34.557842] ? lock_acquire+0x170/0x3f0 [ 34.561794] ? genl_rcv_msg+0x112/0x140 [ 34.565743] genl_family_rcv_msg+0x57c/0xb30 [ 34.570127] ? mark_lock+0x2d5/0x10b0 [ 34.573902] ? genl_unregister_family+0x640/0x640 [ 34.578716] ? mutex_trylock+0x1a0/0x1a0 [ 34.582758] genl_rcv_msg+0xaf/0x140 [ 34.586466] netlink_rcv_skb+0x127/0x370 [ 34.590518] ? genl_family_rcv_msg+0xb30/0xb30 [ 34.595088] ? netlink_ack+0x980/0x980 [ 34.598948] ? lock_acquire+0x170/0x3f0 [ 34.602900] genl_rcv+0x24/0x40 [ 34.606155] netlink_unicast+0x437/0x620 [ 34.610206] ? netlink_attachskb+0x600/0x600 [ 34.614590] netlink_sendmsg+0x733/0xbe0 [ 34.618645] ? netlink_unicast+0x620/0x620 [ 34.622854] ? SYSC_sendto+0x2b0/0x2b0 [ 34.626719] ? security_socket_sendmsg+0x83/0xb0 [ 34.631449] ? netlink_unicast+0x620/0x620 [ 34.635681] sock_sendmsg+0xc5/0x100 [ 34.639388] ___sys_sendmsg+0x70a/0x840 [ 34.643358] ? copy_msghdr_from_user+0x380/0x380 [ 34.648120] ? lock_downgrade+0x6e0/0x6e0 [ 34.652243] ? __lock_acquire+0x5f7/0x4620 [ 34.656456] ? trace_hardirqs_on+0x10/0x10 [ 34.660667] ? trace_hardirqs_on+0x10/0x10 [ 34.664878] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 34.670302] ? save_trace+0x290/0x290 [ 34.674092] ? find_held_lock+0x2d/0x110 [ 34.678130] ? __fget_light+0x16a/0x1f0 [ 34.682079] ? sockfd_lookup_light+0xb2/0x160 [ 34.686656] __sys_sendmsg+0xa3/0x120 [ 34.691213] ? SyS_shutdown+0x160/0x160 [ 34.695163] ? _raw_spin_unlock_irq+0x24/0x8