============================= WARNING: suspicious RCU usage 5.5.0-rc6-next-20200116-syzkaller #0 Not tainted ----------------------------- net/netfilter/ipset/ip_set_core.c:1001 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by syz-executor.0/10390: #0: ffff88809726c5d8 (nlk_cb_mutex-NETFILTER){+.+.}, at: netlink_dump+0xe7/0xfb0 net/netlink/af_netlink.c:2199 stack backtrace: CPU: 0 PID: 10390 Comm: syz-executor.0 Not tainted 5.5.0-rc6-next-20200116-syzkaller #0 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+0x197/0x210 lib/dump_stack.c:118 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5434 find_set_and_id.isra.0+0x227/0x330 net/netfilter/ipset/ip_set_core.c:1001 dump_init+0x1c1/0x3b0 net/netfilter/ipset/ip_set_core.c:1506 ip_set_dump_start+0x9e6/0x1ca0 net/netfilter/ipset/ip_set_core.c:1541 netlink_dump+0x558/0xfb0 net/netlink/af_netlink.c:2244 netlink_recvmsg+0xbb4/0xf50 net/netlink/af_netlink.c:2000 sock_recvmsg_nosec net/socket.c:886 [inline] sock_recvmsg net/socket.c:904 [inline] sock_recvmsg+0xce/0x110 net/socket.c:900 __sys_recvfrom+0x1ff/0x350 net/socket.c:2055 __do_sys_recvfrom net/socket.c:2073 [inline] __se_sys_recvfrom net/socket.c:2069 [inline] __x64_sys_recvfrom+0xe1/0x1a0 net/socket.c:2069 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45b349 Code: ad b6 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 b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f8fb5abec78 EFLAGS: 00000246 ORIG_RAX: 000000000000002d RAX: ffffffffffffffda RBX: 00007f8fb5abf6d4 RCX: 000000000045b349 RDX: 36ff0824c68970de RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000226 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000860 R14: 00000000004c9c9c R15: 000000000075bf2c