============================= WARNING: suspicious RCU usage 5.5.0-rc5-syzkaller #0 Not tainted ----------------------------- net/netfilter/ipset/ip_set_core.c:1001 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.1/10673: #0: ffff8880a33de5d8 (nlk_cb_mutex-NETFILTER){+.+.}, at: netlink_dump+0x75/0x1170 net/netlink/af_netlink.c:2199 stack backtrace: CPU: 0 PID: 10673 Comm: syz-executor.1 Not tainted 5.5.0-rc5-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+0x1fb/0x318 lib/dump_stack.c:118 lockdep_rcu_suspicious+0x156/0x1c0 kernel/locking/lockdep.c:5435 find_set_and_id+0x16f/0x320 net/netfilter/ipset/ip_set_core.c:1001 dump_init net/netfilter/ipset/ip_set_core.c:1506 [inline] ip_set_dump_start+0x73a/0x1660 net/netfilter/ipset/ip_set_core.c:1541 netlink_dump+0x4ed/0x1170 net/netlink/af_netlink.c:2244 netlink_recvmsg+0x659/0xfb0 net/netlink/af_netlink.c:2000 sock_recvmsg_nosec net/socket.c:873 [inline] sock_recvmsg net/socket.c:891 [inline] __sys_recvfrom+0x328/0x4b0 net/socket.c:2042 __do_sys_recvfrom net/socket.c:2060 [inline] __se_sys_recvfrom net/socket.c:2056 [inline] __x64_sys_recvfrom+0xe5/0x100 net/socket.c:2056 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45aff9 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:00007ffaca327c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002d RAX: ffffffffffffffda RBX: 00007ffaca3286d4 RCX: 000000000045aff9 RDX: 36ff0824c68970de RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000226 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000085c R14: 00000000004c9852 R15: 000000000075bf2c