tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: b0523c7b1c9d0edcd6c0fe6d2cb558a9ad5c60a8 commit: ee04805ff54a63ffd90bc6749ebfe73473734ddb [11987/12912] netfilter: conntrack: make conntrack userspace helpers work again config: x86_64-allyesconfig (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 3393cc4cebf9969db94dc424b7a2b6195589c33b) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu git checkout ee04805ff54a63ffd90bc6749ebfe73473734ddb # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>, old ones prefixed by <<): In file included from net/netfilter/nf_conntrack_core.c:51: In file included from include/net/netfilter/nf_nat.h:7: include/linux/netfilter/nf_conntrack_pptp.h:13:20: warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers] extern const char *const pptp_msg_name(u_int16_t msg); ^~~~~~ nf_ct_set(skb, ct, ctinfo); ^~~~~~ net/netfilter/nf_conntrack_core.c:2024:2: note: variable 'ctinfo' is declared here enum ip_conntrack_info ctinfo; ^ 2 warnings generated. vim +/ctinfo +2068 net/netfilter/nf_conntrack_core.c 9fb9cbb1082d6b Yasuyuki Kozakai 2005-11-09 2018 ee04805ff54a63 Pablo Neira Ayuso 2020-05-24 2019 static int __nf_conntrack_update(struct net *net, struct sk_buff *skb, ee04805ff54a63 Pablo Neira Ayuso 2020-05-24 2020 struct nf_conn *ct) 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2021 { 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2022 struct nf_conntrack_tuple_hash *h; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2023 struct nf_conntrack_tuple tuple; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2024 enum ip_conntrack_info ctinfo; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2025 struct nf_nat_hook *nat_hook; 6816d931cab009 Florian Westphal 2018-06-29 2026 unsigned int status; 6816d931cab009 Florian Westphal 2018-06-29 2027 int dataoff; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2028 u16 l3num; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2029 u8 l4num; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2030 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2031 l3num = nf_ct_l3num(ct); 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2032 6816d931cab009 Florian Westphal 2018-06-29 2033 dataoff = get_l4proto(skb, skb_network_offset(skb), l3num, &l4num); 6816d931cab009 Florian Westphal 2018-06-29 2034 if (dataoff <= 0) 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2035 return -1; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2036 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2037 if (!nf_ct_get_tuple(skb, skb_network_offset(skb), dataoff, l3num, 303e0c5589592e Florian Westphal 2019-01-15 2038 l4num, net, &tuple)) 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2039 return -1; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2040 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2041 if (ct->status & IPS_SRC_NAT) { 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2042 memcpy(tuple.src.u3.all, 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2043 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.all, 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2044 sizeof(tuple.src.u3.all)); 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2045 tuple.src.u.all = 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2046 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.all; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2047 } 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2048 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2049 if (ct->status & IPS_DST_NAT) { 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2050 memcpy(tuple.dst.u3.all, 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2051 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.all, 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2052 sizeof(tuple.dst.u3.all)); 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2053 tuple.dst.u.all = 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2054 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.all; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2055 } 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2056 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2057 h = nf_conntrack_find_get(net, nf_ct_zone(ct), &tuple); 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2058 if (!h) 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2059 return 0; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2060 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2061 /* Store status bits of the conntrack that is clashing to re-do NAT 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2062 * mangling according to what it has been done already to this packet. 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2063 */ 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2064 status = ct->status; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2065 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2066 nf_ct_put(ct); 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2067 ct = nf_ct_tuplehash_to_ctrack(h); 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 @2068 nf_ct_set(skb, ct, ctinfo); 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2069 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2070 nat_hook = rcu_dereference(nf_nat_hook); 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2071 if (!nat_hook) 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2072 return 0; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2073 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2074 if (status & IPS_SRC_NAT && 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2075 nat_hook->manip_pkt(skb, ct, NF_NAT_MANIP_SRC, 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2076 IP_CT_DIR_ORIGINAL) == NF_DROP) 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2077 return -1; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2078 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2079 if (status & IPS_DST_NAT && 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2080 nat_hook->manip_pkt(skb, ct, NF_NAT_MANIP_DST, 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2081 IP_CT_DIR_ORIGINAL) == NF_DROP) 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2082 return -1; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2083 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2084 return 0; 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2085 } 368982cd7d1bd4 Pablo Neira Ayuso 2018-05-23 2086 :::::: The code at line 2068 was first introduced by commit :::::: 368982cd7d1bd41cd39049c794990aca3770db44 netfilter: nfnetlink_queue: resolve clash for unconfirmed conntracks :::::: TO: Pablo Neira Ayuso <pablo(a)netfilter.org&gt; :::::: CC: Pablo Neira Ayuso <pablo(a)netfilter.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org