[PATCH] netfilter: extend CONFIG_NF_CONNTRACK compile time checks

[trix@redhat.com]

From: Tom Rix <trix@redhat.com>

Extends
commit 83ace77f5117 ("netfilter: ctnetlink: remove get_ct indirection")

Add some compile time checks by following the ct and ctinfo variables
that are only set when CONFIG_NF_CONNTRACK is enabled.

In nfulnl_log_packet(), ct is only set when CONFIG_NF_CONNTRACK
is enabled. ct's later use in __build_packet_message() is only
meaningful when CONFIG_NF_CONNTRACK is enabled, so add a check.

In nfqnl_build_packet_message(), ct and ctinfo are only set when
CONFIG_NF_CONNTRACK is enabled.  Add a check for their decl and use.

nfqnl_ct_parse() is a static function, move the check to the whole
function.

In nfqa_parse_bridge(), ct and ctinfo are only set by the only
call to nfqnl_ct_parse(), so add a check for their decl and use.

Consistently initialize ctinfo to 0.

Signed-off-by: Tom Rix <trix@redhat.com>
---
 net/netfilter/nfnetlink_log.c   |  4 +++-
 net/netfilter/nfnetlink_queue.c | 18 +++++++++++++-----
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c
index ae9c0756bba59..e79d152184b71 100644
--- a/net/netfilter/nfnetlink_log.c
+++ b/net/netfilter/nfnetlink_log.c
@@ -627,9 +627,11 @@ __build_packet_message(struct nfnl_log_net *log,
 			 htonl(atomic_inc_return(&log->global_seq))))
 		goto nla_put_failure;
 
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 	if (ct && nfnl_ct->build(inst->skb, ct, ctinfo,
 				 NFULA_CT, NFULA_CT_INFO) < 0)
 		goto nla_put_failure;
+#endif
 
 	if ((pf == NFPROTO_NETDEV || pf == NFPROTO_BRIDGE) &&
 	    nfulnl_put_bridge(inst, skb) < 0)
@@ -689,7 +691,7 @@ nfulnl_log_packet(struct net *net,
 	struct nfnl_log_net *log = nfnl_log_pernet(net);
 	const struct nfnl_ct_hook *nfnl_ct = NULL;
 	struct nf_conn *ct = NULL;
-	enum ip_conntrack_info ctinfo;
+	enum ip_conntrack_info ctinfo = 0;
 
 	if (li_user && li_user->type == NF_LOG_TYPE_ULOG)
 		li = li_user;
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 44c3de176d186..d59cae7561bf8 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -386,8 +386,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	struct sk_buff *entskb = entry->skb;
 	struct net_device *indev;
 	struct net_device *outdev;
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 	struct nf_conn *ct = NULL;
 	enum ip_conntrack_info ctinfo = 0;
+#endif
 	struct nfnl_ct_hook *nfnl_ct;
 	bool csum_verify;
 	char *secdata = NULL;
@@ -595,8 +597,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))
 		goto nla_put_failure;
 
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 	if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
 		goto nla_put_failure;
+#endif
 
 	if (cap_len > data_len &&
 	    nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len)))
@@ -1104,13 +1108,13 @@ static int nfqnl_recv_verdict_batch(struct sk_buff *skb,
 	return 0;
 }
 
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 static struct nf_conn *nfqnl_ct_parse(struct nfnl_ct_hook *nfnl_ct,
 				      const struct nlmsghdr *nlh,
 				      const struct nlattr * const nfqa[],
 				      struct nf_queue_entry *entry,
 				      enum ip_conntrack_info *ctinfo)
 {
-#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 	struct nf_conn *ct;
 
 	ct = nf_ct_get(entry->skb, ctinfo);
@@ -1125,10 +1129,8 @@ static struct nf_conn *nfqnl_ct_parse(struct nfnl_ct_hook *nfnl_ct,
 				      NETLINK_CB(entry->skb).portid,
 				      nlmsg_report(nlh));
 	return ct;
-#else
-	return NULL;
-#endif
 }
+#endif
 
 static int nfqa_parse_bridge(struct nf_queue_entry *entry,
 			     const struct nlattr * const nfqa[])
@@ -1172,11 +1174,13 @@ static int nfqnl_recv_verdict(struct sk_buff *skb, const struct nfnl_info *info,
 	struct nfnl_queue_net *q = nfnl_queue_pernet(info->net);
 	u_int16_t queue_num = ntohs(info->nfmsg->res_id);
 	struct nfqnl_msg_verdict_hdr *vhdr;
-	enum ip_conntrack_info ctinfo;
 	struct nfqnl_instance *queue;
 	struct nf_queue_entry *entry;
 	struct nfnl_ct_hook *nfnl_ct;
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 	struct nf_conn *ct = NULL;
+	enum ip_conntrack_info ctinfo = 0;
+#endif
 	unsigned int verdict;
 	int err;
 
@@ -1198,11 +1202,13 @@ static int nfqnl_recv_verdict(struct sk_buff *skb, const struct nfnl_info *info,
 	/* rcu lock already held from nfnl->call_rcu. */
 	nfnl_ct = rcu_dereference(nfnl_ct_hook);
 
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 	if (nfqa[NFQA_CT]) {
 		if (nfnl_ct != NULL)
 			ct = nfqnl_ct_parse(nfnl_ct, info->nlh, nfqa, entry,
 					    &ctinfo);
 	}
+#endif
 
 	if (entry->state.pf == PF_BRIDGE) {
 		err = nfqa_parse_bridge(entry, nfqa);
@@ -1218,8 +1224,10 @@ static int nfqnl_recv_verdict(struct sk_buff *skb, const struct nfnl_info *info,
 				 payload_len, entry, diff) < 0)
 			verdict = NF_DROP;
 
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 		if (ct && diff)
 			nfnl_ct->seq_adjust(entry->skb, ct, ctinfo, diff);
+#endif
 	}
 
 	if (nfqa[NFQA_MARK])
-- 
2.26.3