More compatibility checking and simplifications

Try hard to keep the support of the 2.6.32 kernel tree and
simplify the code with self-referential macros.

7 files changed, 64 insertions, 33 deletions

diff --git a/kernel/include/linux/netfilter/ipset/ip_set.h b/kernel/include/linux/netfilter/ipset/ip_set.h
index c65c218..e62bbe8 100644
--- a/kernel/include/linux/netfilter/ipset/ip_set.h
+++ b/kernel/include/linux/netfilter/ipset/ip_set.h
@@ -18,8 +18,8 @@
 #include <linux/stringify.h>
 #include <linux/vmalloc.h>
 #include <net/netlink.h>
-#include <uapi/linux/netfilter/ipset/ip_set.h>
 #include <linux/netfilter/ipset/ip_set_compat.h>
+#include <uapi/linux/netfilter/ipset/ip_set.h>
 
 #define _IP_SET_MODULE_DESC(a, b, c)		\
 	MODULE_DESCRIPTION(a " type of IP sets, revisions " b "-" c)
diff --git a/kernel/include/linux/netfilter/ipset/ip_set_compat.h.in b/kernel/include/linux/netfilter/ipset/ip_set_compat.h.in
index 64d6169..66e830f 100644
--- a/kernel/include/linux/netfilter/ipset/ip_set_compat.h.in
+++ b/kernel/include/linux/netfilter/ipset/ip_set_compat.h.in
@@ -41,6 +41,7 @@
 #@HAVE_TCF_EMATCH_OPS_CHANGE_ARG_NET@ HAVE_TCF_EMATCH_OPS_CHANGE_ARG_NET
 #@HAVE_TCF_EMATCH_STRUCT_NET@ HAVE_TCF_EMATCH_STRUCT_NET
 #@HAVE_LIST_LAST_ENTRY@ HAVE_LIST_LAST_ENTRY
+#@HAVE_LIST_NEXT_ENTRY@ HAVE_LIST_NEXT_ENTRY
 
 /* Not everything could be moved here. Compatibility stuffs can be found in
  * xt_set.c, ip_set_core.c, ip_set_getport.c, pfxlen.c too.
@@ -78,6 +79,26 @@
 #endif
 #endif
 
+#ifndef kfree_rcu
+
+static inline void kfree_call_rcu(struct rcu_head *head,
+				  void (*func)(struct rcu_head *rcu))
+{
+	call_rcu(head, func);
+}
+
+#define __is_kfree_rcu_offset(offset) ((offset) < 4096)
+
+#define __kfree_rcu(head, offset)	\
+do {				\
+	BUILD_BUG_ON(!__is_kfree_rcu_offset(offset));	\
+	kfree_call_rcu(head, (void (*)(struct rcu_head *))(unsigned long)(offset)); \
+} while (0)
+
+#define kfree_rcu(ptr, rcu_head)	\
+	__kfree_rcu(&((ptr)->rcu_head), offsetof(typeof(*(ptr)), rcu_head))
+#endif
+
 #ifdef CHECK_KCONFIG
 #ifndef CONFIG_SPARSE_RCU_POINTER
 #error "CONFIG_SPARSE_RCU_POINTER must be enabled"
@@ -126,16 +147,18 @@ static inline int nla_put_net64(struct sk_buff *skb, int attrtype, __be64 value)
 #define NETLINK_PORTID(skb)	NETLINK_CB(skb).pid
 #endif
 
-#ifndef HAVE_NS_CAPABLE
+#ifndef HAVE_USER_NS_IN_STRUCT_NET
 #define ns_capable(ns, cap)	capable(cap)
 #endif
 
-#ifdef HAVE_NFNL_LOCK_SUBSYS
-#define lock_nfnl()		nfnl_lock(NFNL_SUBSYS_IPSET)
-#define unlock_nfnl()		nfnl_unlock(NFNL_SUBSYS_IPSET)
-#else
-#define lock_nfnl()		nfnl_lock()
-#define unlock_nfnl()		nfnl_unlock()
+#ifndef HAVE_NFNL_LOCK_SUBSYS
+#define nfnl_lock(x)		nfnl_lock()
+#define nfnl_unlock(x)		nfnl_unlock()
+#endif
+
+#if HAVE_IPV6_SKIP_EXTHDR_ARGS == 3
+#define ipv6_skip_exthdr(skbuff, start, nexthdrp, frag_offp)	\
+	ipv6_skip_exthdr(skbuff, start, nexthdrp)
 #endif
 
 #ifndef HAVE_KVFREE
@@ -174,5 +197,23 @@ static inline int nla_put_net32(struct sk_buff *skb, int attrtype, __be32 value)
 #define list_last_entry(ptr, type, member) \
 	list_entry((ptr)->prev, type, member)
 #endif
+#ifndef HAVE_LIST_NEXT_ENTRY
+#define list_next_entry(pos, member)	\
+	list_entry((pos)->member.next, typeof(*(pos)), member)
+#define list_prev_entry(pos, member)	\
+	list_entry((pos)->member.prev, typeof(*(pos)), member)
+#endif
+
+#ifndef __aligned_u64
+#define __aligned_u64 __u64
+#endif
+
+#ifndef pr_warn
+#define pr_warn	pr_warning
+#endif
+
+#ifndef SIZE_MAX
+#define SIZE_MAX	(~(size_t)0)
+#endif
 
 #endif /* __IP_SET_COMPAT_H */
diff --git a/kernel/include/uapi/linux/netfilter/ipset/ip_set.h b/kernel/include/uapi/linux/netfilter/ipset/ip_set.h
index 93549ef..63b2e34 100644
--- a/kernel/include/uapi/linux/netfilter/ipset/ip_set.h
+++ b/kernel/include/uapi/linux/netfilter/ipset/ip_set.h
@@ -10,7 +10,6 @@
 #ifndef _UAPI_IP_SET_H
 #define _UAPI_IP_SET_H
 
-
 #include <linux/types.h>
 
 /* The protocol version */
diff --git a/kernel/net/netfilter/ipset/ip_set_core.c b/kernel/net/netfilter/ipset/ip_set_core.c
index 5869d69..ab4110a 100644
--- a/kernel/net/netfilter/ipset/ip_set_core.c
+++ b/kernel/net/netfilter/ipset/ip_set_core.c
@@ -15,7 +15,6 @@
 #include <linux/ip.h>
 #include <linux/skbuff.h>
 #include <linux/spinlock.h>
-#include <linux/netlink.h>
 #include <linux/rculist.h>
 #include <net/netlink.h>
 #include <net/net_namespace.h>
@@ -104,14 +103,14 @@ find_set_type(const char *name, u8 family, u8 revision)
 static bool
 load_settype(const char *name)
 {
-	unlock_nfnl();
+	nfnl_unlock(NFNL_SUBSYS_IPSET);
 	pr_debug("try to load ip_set_%s\n", name);
 	if (request_module("ip_set_%s", name) < 0) {
 		pr_warn("Can't find ip_set type %s\n", name);
-		lock_nfnl();
+		nfnl_lock(NFNL_SUBSYS_IPSET);
 		return false;
 	}
-	lock_nfnl();
+	nfnl_lock(NFNL_SUBSYS_IPSET);
 	return true;
 }
 
@@ -663,13 +662,13 @@ ip_set_nfnl_get_byindex(struct net *net, ip_set_id_t index)
 	if (index >= inst->ip_set_max)
 		return IPSET_INVALID_ID;
 
-	lock_nfnl();
+	nfnl_lock(NFNL_SUBSYS_IPSET);
 	set = ip_set(inst, index);
 	if (set)
 		__ip_set_get(set);
 	else
 		index = IPSET_INVALID_ID;
-	unlock_nfnl();
+	nfnl_unlock(NFNL_SUBSYS_IPSET);
 
 	return index;
 }
@@ -687,13 +686,13 @@ ip_set_nfnl_put(struct net *net, ip_set_id_t index)
 	struct ip_set *set;
 	struct ip_set_net *inst = ip_set_pernet(net);
 
-	lock_nfnl();
+	nfnl_lock(NFNL_SUBSYS_IPSET);
 	if (!inst->is_deleted) { /* already deleted from ip_set_net_exit() */
 		set = ip_set(inst, index);
 		if (set != NULL)
 			__ip_set_put(set);
 	}
-	unlock_nfnl();
+	nfnl_unlock(NFNL_SUBSYS_IPSET);
 }
 EXPORT_SYMBOL_GPL(ip_set_nfnl_put);
 
@@ -1856,11 +1855,7 @@ ip_set_sockfn_get(struct sock *sk, int optval, void __user *user, int *len)
 	struct net *net = sock_net(sk);
 	struct ip_set_net *inst = ip_set_pernet(net);
 
-#ifdef HAVE_USER_NS_IN_STRUCT_NET
 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
-#else
-	if (!capable(CAP_NET_ADMIN))
-#endif
 		return -EPERM;
 	if (optval != SO_IP_SET)
 		return -EBADF;
@@ -1914,10 +1909,10 @@ ip_set_sockfn_get(struct sock *sk, int optval, void __user *user, int *len)
 			goto done;
 		}
 		req_get->set.name[IPSET_MAXNAMELEN - 1] = '\0';
-		lock_nfnl();
+		nfnl_lock(NFNL_SUBSYS_IPSET);
 		find_set_and_id(inst, req_get->set.name, &id);
 		req_get->set.index = id;
-		unlock_nfnl();
+		nfnl_unlock(NFNL_SUBSYS_IPSET);
 		goto copy;
 	}
 	case IP_SET_OP_GET_FNAME: {
@@ -1929,12 +1924,12 @@ ip_set_sockfn_get(struct sock *sk, int optval, void __user *user, int *len)
 			goto done;
 		}
 		req_get->set.name[IPSET_MAXNAMELEN - 1] = '\0';
-		lock_nfnl();
+		nfnl_lock(NFNL_SUBSYS_IPSET);
 		find_set_and_id(inst, req_get->set.name, &id);
 		req_get->set.index = id;
 		if (id != IPSET_INVALID_ID)
 			req_get->family = ip_set(inst, id)->family;
-		unlock_nfnl();
+		nfnl_unlock(NFNL_SUBSYS_IPSET);
 		goto copy;
 	}
 	case IP_SET_OP_GET_BYINDEX: {
@@ -1946,11 +1941,11 @@ ip_set_sockfn_get(struct sock *sk, int optval, void __user *user, int *len)
 			ret = -EINVAL;
 			goto done;
 		}
-		lock_nfnl();
+		nfnl_lock(NFNL_SUBSYS_IPSET);
 		set = ip_set(inst, req_get->set.index);
 		strncpy(req_get->set.name, set ? set->name : "",
 			IPSET_MAXNAMELEN);
-		unlock_nfnl();
+		nfnl_unlock(NFNL_SUBSYS_IPSET);
 		goto copy;
 	}
 	default:
diff --git a/kernel/net/netfilter/ipset/ip_set_getport.c b/kernel/net/netfilter/ipset/ip_set_getport.c
index 956c84a..4d9a2c0 100644
--- a/kernel/net/netfilter/ipset/ip_set_getport.c
+++ b/kernel/net/netfilter/ipset/ip_set_getport.c
@@ -140,12 +140,8 @@ ip_set_get_ip6_port(const struct sk_buff *skb, bool src,
 	__be16 frag_off = 0;
 
 	nexthdr = ipv6_hdr(skb)->nexthdr;
-#if HAVE_IPV6_SKIP_EXTHDR_ARGS == 4
 	protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
 				   &frag_off);
-#else
-	protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr);
-#endif
 	if (protoff < 0 || (frag_off & htons(~0x7)) != 0)
 		return false;
 
diff --git a/kernel/net/netfilter/ipset/ip_set_hash_ipmark.c b/kernel/net/netfilter/ipset/ip_set_hash_ipmark.c
index c96a61c..71468d5 100644
--- a/kernel/net/netfilter/ipset/ip_set_hash_ipmark.c
+++ b/kernel/net/netfilter/ipset/ip_set_hash_ipmark.c
@@ -215,7 +215,6 @@ hash_ipmark6_data_next(struct hash_ipmark4_elem *next,
 #define	IP_SET_EMIT_CREATE
 #include "ip_set_hash_gen.h"
 
-
 static int
 hash_ipmark6_kadt(struct ip_set *set, const struct sk_buff *skb,
 		  const struct xt_action_param *par,
diff --git a/kernel/net/netfilter/xt_set.c b/kernel/net/netfilter/xt_set.c
index 9953a7b..6e2ab11 100644
--- a/kernel/net/netfilter/xt_set.c
+++ b/kernel/net/netfilter/xt_set.c
@@ -486,7 +486,8 @@ set_target_v3(struct sk_buff *skb, const struct xt_action_param *par)
 		map_opt.cmdflags |= info->flags & (IPSET_FLAG_MAP_SKBMARK |
 						   IPSET_FLAG_MAP_SKBPRIO |
 						   IPSET_FLAG_MAP_SKBQUEUE);
-		ret = match_set(info->map_set.index, skb, par, &map_opt,
+		ret = match_set(info->map_set.index, skb, CAST_TO_MATCH par,
+				&map_opt,
 				info->map_set.flags & IPSET_INV_MATCH);
 		if (!ret)
 			return XT_CONTINUE;