============================= WARNING: suspicious RCU usage 5.1.0-rc1-next-20190318 #5 Not tainted ----------------------------- net/xfrm/xfrm_user.c:1080 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by syz-executor.0/14590: #0: 00000000682f3cce (&net->xfrm.xfrm_cfg_mutex){+.+.}, at: xfrm_netlink_rcv+0x61/0x90 net/xfrm/xfrm_user.c:2691 stack backtrace: CPU: 0 PID: 14590 Comm: syz-executor.0 Not tainted 5.1.0-rc1-next-20190318 #5 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5162 xfrm_nlmsg_unicast net/xfrm/xfrm_user.c:1080 [inline] xfrm_alloc_userspi+0x7d5/0xa80 net/xfrm/xfrm_user.c:1356 xfrm_user_rcv_msg+0x458/0x770 net/xfrm/xfrm_user.c:2684 netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2485 xfrm_netlink_rcv+0x70/0x90 net/xfrm/xfrm_user.c:2692 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1925 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:661 ___sys_sendmsg+0x806/0x930 net/socket.c:2260 __sys_sendmsg+0x105/0x1d0 net/socket.c:2298 __do_sys_sendmsg net/socket.c:2307 [inline] __se_sys_sendmsg net/socket.c:2305 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2305 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458079 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f03c31c8c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458079 RDX: 0000000000000000 RSI: 00000000200003c0 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f03c31c96d4 R13: 00000000004c56c3 R14: 00000000004d95f0 R15: 00000000ffffffff