netfilter: xtables: replace XT_MATCH_ITERATE macro

The macro is replaced by a list.h-like foreach loop. This makes
the code more inspectable.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h
index 9df3f5a..84c7c92 100644 (file)
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -120,6 +120,7 @@ struct xt_counters_info {
 
 #define XT_INV_PROTO           0x40    /* Invert the sense of PROTO. */
 
+#ifndef __KERNEL__
 /* fn returns 0 to continue iteration */
 #define XT_MATCH_ITERATE(type, e, fn, args...)                 \
 ({                                                             \
@@ -139,7 +140,6 @@ struct xt_counters_info {
        __ret;                                                  \
 })
 
-#ifndef __KERNEL__
 /* fn returns 0 to continue iteration */
 #define XT_ENTRY_ITERATE_CONTINUE(type, entries, size, n, fn, args...) \
 ({                                                             \
@@ -172,6 +172,14 @@ struct xt_counters_info {
             (pos) < (typeof(pos))((char *)(ehead) + (esize)); \
             (pos) = (typeof(pos))((char *)(pos) + (pos)->next_offset))
 
+/* can only be xt_entry_match, so no use of typeof here */
+#define xt_ematch_foreach(pos, entry) \
+       for ((pos) = (struct xt_entry_match *)entry->elems; \
+            (pos) < (struct xt_entry_match *)((char *)(entry) + \
+                    (entry)->target_offset); \
+            (pos) = (struct xt_entry_match *)((char *)(pos) + \
+                    (pos)->u.match_size))
+
 #ifdef __KERNEL__
 
 #include <linux/netdevice.h>

diff --git a/include/linux/netfilter_ipv4/ip_tables.h b/include/linux/netfilter_ipv4/ip_tables.h
index 5b20ae7..704a7b6 100644 (file)
--- a/include/linux/netfilter_ipv4/ip_tables.h
+++ b/include/linux/netfilter_ipv4/ip_tables.h
@@ -223,11 +223,11 @@ ipt_get_target(struct ipt_entry *e)
        return (void *)e + e->target_offset;
 }
 
+#ifndef __KERNEL__
 /* fn returns 0 to continue iteration */
 #define IPT_MATCH_ITERATE(e, fn, args...) \
        XT_MATCH_ITERATE(struct ipt_entry, e, fn, ## args)
 
-#ifndef __KERNEL__
 /* fn returns 0 to continue iteration */
 #define IPT_ENTRY_ITERATE(entries, size, fn, args...) \
        XT_ENTRY_ITERATE(struct ipt_entry, entries, size, fn, ## args)
@@ -315,10 +315,6 @@ compat_ipt_get_target(struct compat_ipt_entry *e)
 
 #define COMPAT_IPT_ALIGN(s)    COMPAT_XT_ALIGN(s)
 
-/* fn returns 0 to continue iteration */
-#define COMPAT_IPT_MATCH_ITERATE(e, fn, args...) \
-       XT_MATCH_ITERATE(struct compat_ipt_entry, e, fn, ## args)
-
 #endif /* CONFIG_COMPAT */
 #endif /*__KERNEL__*/
 #endif /* _IPTABLES_H */

diff --git a/include/linux/netfilter_ipv6/ip6_tables.h b/include/linux/netfilter_ipv6/ip6_tables.h
index 8bb3f5b..e5ba03d 100644 (file)
--- a/include/linux/netfilter_ipv6/ip6_tables.h
+++ b/include/linux/netfilter_ipv6/ip6_tables.h
@@ -280,11 +280,11 @@ ip6t_get_target(struct ip6t_entry *e)
        return (void *)e + e->target_offset;
 }
 
+#ifndef __KERNEL__
 /* fn returns 0 to continue iteration */
 #define IP6T_MATCH_ITERATE(e, fn, args...) \
        XT_MATCH_ITERATE(struct ip6t_entry, e, fn, ## args)
 
-#ifndef __KERNEL__
 /* fn returns 0 to continue iteration */
 #define IP6T_ENTRY_ITERATE(entries, size, fn, args...) \
        XT_ENTRY_ITERATE(struct ip6t_entry, entries, size, fn, ## args)
@@ -343,10 +343,6 @@ compat_ip6t_get_target(struct compat_ip6t_entry *e)
 
 #define COMPAT_IP6T_ALIGN(s)   COMPAT_XT_ALIGN(s)
 
-/* fn returns 0 to continue iteration */
-#define COMPAT_IP6T_MATCH_ITERATE(e, fn, args...) \
-       XT_MATCH_ITERATE(struct compat_ip6t_entry, e, fn, ## args)
-
 #endif /* CONFIG_COMPAT */
 #endif /*__KERNEL__*/
 #endif /* _IP6_TABLES_H */

diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 9c8aa39..3a7fc73 100644 (file)
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -366,16 +366,21 @@ ipt_do_table(struct sk_buff *skb,
 
        do {
                const struct ipt_entry_target *t;
+               const struct xt_entry_match *ematch;
 
                IP_NF_ASSERT(e);
                IP_NF_ASSERT(back);
                if (!ip_packet_match(ip, indev, outdev,
-                   &e->ip, mtpar.fragoff) ||
-                   IPT_MATCH_ITERATE(e, do_match, skb, &mtpar) != 0) {
+                   &e->ip, mtpar.fragoff)) {
+ no_match:
                        e = ipt_next_entry(e);
                        continue;
                }
 
+               xt_ematch_foreach(ematch, e)
+                       if (do_match(ematch, skb, &mtpar) != 0)
+                               goto no_match;
+
                ADD_COUNTER(e->counters, ntohs(ip->tot_len), 1);
 
                t = ipt_get_target(e);
@@ -686,6 +691,7 @@ find_check_entry(struct ipt_entry *e, struct net *net, const char *name,
        int ret;
        unsigned int j;
        struct xt_mtchk_param mtpar;
+       struct xt_entry_match *ematch;
 
        ret = check_entry(e, name);
        if (ret)
@@ -697,7 +703,11 @@ find_check_entry(struct ipt_entry *e, struct net *net, const char *name,
        mtpar.entryinfo = &e->ip;
        mtpar.hook_mask = e->comefrom;
        mtpar.family    = NFPROTO_IPV4;
-       ret = IPT_MATCH_ITERATE(e, find_check_match, &mtpar, &j);
+       xt_ematch_foreach(ematch, e) {
+               ret = find_check_match(ematch, &mtpar, &j);
+               if (ret != 0)
+                       break;
+       }
        if (ret != 0)
                goto cleanup_matches;
 
@@ -720,7 +730,9 @@ find_check_entry(struct ipt_entry *e, struct net *net, const char *name,
  err:
        module_put(t->u.kernel.target->me);
  cleanup_matches:
-       IPT_MATCH_ITERATE(e, cleanup_match, net, &j);
+       xt_ematch_foreach(ematch, e)
+               if (cleanup_match(ematch, net, &j) != 0)
+                       break;
        return ret;
 }
 
@@ -791,9 +803,12 @@ cleanup_entry(struct ipt_entry *e, struct net *net)
 {
        struct xt_tgdtor_param par;
        struct ipt_entry_target *t;
+       struct xt_entry_match *ematch;
 
        /* Cleanup all matches */
-       IPT_MATCH_ITERATE(e, cleanup_match, net, NULL);
+       xt_ematch_foreach(ematch, e)
+               if (cleanup_match(ematch, net, NULL) != 0)
+                       break;
        t = ipt_get_target(e);
 
        par.net      = net;
@@ -1060,13 +1075,16 @@ static int compat_calc_entry(const struct ipt_entry *e,
                             const struct xt_table_info *info,
                             const void *base, struct xt_table_info *newinfo)
 {
+       const struct xt_entry_match *ematch;
        const struct ipt_entry_target *t;
        unsigned int entry_offset;
        int off, i, ret;
 
        off = sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
        entry_offset = (void *)e - base;
-       IPT_MATCH_ITERATE(e, compat_calc_match, &off);
+       xt_ematch_foreach(ematch, e)
+               if (compat_calc_match(ematch, &off) != 0)
+                       break;
        t = ipt_get_target_c(e);
        off += xt_compat_target_offset(t->u.kernel.target);
        newinfo->size -= off;
@@ -1441,7 +1459,8 @@ compat_copy_entry_to_user(struct ipt_entry *e, void __user **dstptr,
        struct compat_ipt_entry __user *ce;
        u_int16_t target_offset, next_offset;
        compat_uint_t origsize;
-       int ret;
+       const struct xt_entry_match *ematch;
+       int ret = 0;
 
        origsize = *size;
        ce = (struct compat_ipt_entry __user *)*dstptr;
@@ -1453,7 +1472,11 @@ compat_copy_entry_to_user(struct ipt_entry *e, void __user **dstptr,
        *dstptr += sizeof(struct compat_ipt_entry);
        *size -= sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
 
-       ret = IPT_MATCH_ITERATE(e, xt_compat_match_to_user, dstptr, size);
+       xt_ematch_foreach(ematch, e) {
+               ret = xt_compat_match_to_user(ematch, dstptr, size);
+               if (ret != 0)
+                       break;
+       }
        target_offset = e->target_offset - (origsize - *size);
        if (ret)
                return ret;
@@ -1505,9 +1528,12 @@ compat_release_match(struct ipt_entry_match *m, unsigned int *i)
 static void compat_release_entry(struct compat_ipt_entry *e)
 {
        struct ipt_entry_target *t;
+       struct xt_entry_match *ematch;
 
        /* Cleanup all matches */
-       COMPAT_IPT_MATCH_ITERATE(e, compat_release_match, NULL);
+       xt_ematch_foreach(ematch, e)
+               if (compat_release_match(ematch, NULL) != 0)
+                       break;
        t = compat_ipt_get_target(e);
        module_put(t->u.kernel.target->me);
 }
@@ -1522,6 +1548,7 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
                                  const unsigned int *underflows,
                                  const char *name)
 {
+       struct xt_entry_match *ematch;
        struct ipt_entry_target *t;
        struct xt_target *target;
        unsigned int entry_offset;
@@ -1550,8 +1577,12 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
        off = sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
        entry_offset = (void *)e - (void *)base;
        j = 0;
-       ret = COMPAT_IPT_MATCH_ITERATE(e, compat_find_calc_match, name,
-                                      &e->ip, e->comefrom, &off, &j);
+       xt_ematch_foreach(ematch, e) {
+               ret = compat_find_calc_match(ematch, name,
+                     &e->ip, e->comefrom, &off, &j);
+               if (ret != 0)
+                       break;
+       }
        if (ret != 0)
                goto release_matches;
 
@@ -1590,7 +1621,9 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
 out:
        module_put(t->u.kernel.target->me);
 release_matches:
-       IPT_MATCH_ITERATE(e, compat_release_match, &j);
+       xt_ematch_foreach(ematch, e)
+               if (compat_release_match(ematch, &j) != 0)
+                       break;
        return ret;
 }
 
@@ -1604,6 +1637,7 @@ compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr,
        struct ipt_entry *de;
        unsigned int origsize;
        int ret, h;
+       struct xt_entry_match *ematch;
 
        ret = 0;
        origsize = *size;
@@ -1614,8 +1648,11 @@ compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr,
        *dstptr += sizeof(struct ipt_entry);
        *size += sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
 
-       ret = COMPAT_IPT_MATCH_ITERATE(e, xt_compat_match_from_user,
-                                      dstptr, size);
+       xt_ematch_foreach(ematch, e) {
+               ret = xt_compat_match_from_user(ematch, dstptr, size);
+               if (ret != 0)
+                       break;
+       }
        if (ret)
                return ret;
        de->target_offset = e->target_offset - (origsize - *size);
@@ -1636,9 +1673,10 @@ compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr,
 static int
 compat_check_entry(struct ipt_entry *e, struct net *net, const char *name)
 {
+       struct xt_entry_match *ematch;
        struct xt_mtchk_param mtpar;
        unsigned int j;
-       int ret;
+       int ret = 0;
 
        j = 0;
        mtpar.net       = net;
@@ -1646,7 +1684,11 @@ compat_check_entry(struct ipt_entry *e, struct net *net, const char *name)
        mtpar.entryinfo = &e->ip;
        mtpar.hook_mask = e->comefrom;
        mtpar.family    = NFPROTO_IPV4;
-       ret = IPT_MATCH_ITERATE(e, check_match, &mtpar, &j);
+       xt_ematch_foreach(ematch, e) {
+               ret = check_match(ematch, &mtpar, &j);
+               if (ret != 0)
+                       break;
+       }
        if (ret)
                goto cleanup_matches;
 
@@ -1656,7 +1698,9 @@ compat_check_entry(struct ipt_entry *e, struct net *net, const char *name)
        return 0;
 
  cleanup_matches:
-       IPT_MATCH_ITERATE(e, cleanup_match, net, &j);
+       xt_ematch_foreach(ematch, e)
+               if (cleanup_match(ematch, net, &j) != 0)
+                       break;
        return ret;
 }
 

diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index b7e27c1..1537e6b 100644 (file)
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -393,16 +393,21 @@ ip6t_do_table(struct sk_buff *skb,
 
        do {
                const struct ip6t_entry_target *t;
+               const struct xt_entry_match *ematch;
 
                IP_NF_ASSERT(e);
                IP_NF_ASSERT(back);
                if (!ip6_packet_match(skb, indev, outdev, &e->ipv6,
-                   &mtpar.thoff, &mtpar.fragoff, &hotdrop) ||
-                   IP6T_MATCH_ITERATE(e, do_match, skb, &mtpar) != 0) {
+                   &mtpar.thoff, &mtpar.fragoff, &hotdrop)) {
+ no_match:
                        e = ip6t_next_entry(e);
                        continue;
                }
 
+               xt_ematch_foreach(ematch, e)
+                       if (do_match(ematch, skb, &mtpar) != 0)
+                               goto no_match;
+
                ADD_COUNTER(e->counters,
                            ntohs(ipv6_hdr(skb)->payload_len) +
                            sizeof(struct ipv6hdr), 1);
@@ -717,6 +722,7 @@ find_check_entry(struct ip6t_entry *e, struct net *net, const char *name,
        int ret;
        unsigned int j;
        struct xt_mtchk_param mtpar;
+       struct xt_entry_match *ematch;
 
        ret = check_entry(e, name);
        if (ret)
@@ -728,7 +734,11 @@ find_check_entry(struct ip6t_entry *e, struct net *net, const char *name,
        mtpar.entryinfo = &e->ipv6;
        mtpar.hook_mask = e->comefrom;
        mtpar.family    = NFPROTO_IPV6;
-       ret = IP6T_MATCH_ITERATE(e, find_check_match, &mtpar, &j);
+       xt_ematch_foreach(ematch, e) {
+               ret = find_check_match(ematch, &mtpar, &j);
+               if (ret != 0)
+                       break;
+       }
        if (ret != 0)
                goto cleanup_matches;
 
@@ -751,7 +761,9 @@ find_check_entry(struct ip6t_entry *e, struct net *net, const char *name,
  err:
        module_put(t->u.kernel.target->me);
  cleanup_matches:
-       IP6T_MATCH_ITERATE(e, cleanup_match, net, &j);
+       xt_ematch_foreach(ematch, e)
+               if (cleanup_match(ematch, net, &j) != 0)
+                       break;
        return ret;
 }
 
@@ -821,9 +833,12 @@ static void cleanup_entry(struct ip6t_entry *e, struct net *net)
 {
        struct xt_tgdtor_param par;
        struct ip6t_entry_target *t;
+       struct xt_entry_match *ematch;
 
        /* Cleanup all matches */
-       IP6T_MATCH_ITERATE(e, cleanup_match, net, NULL);
+       xt_ematch_foreach(ematch, e)
+               if (cleanup_match(ematch, net, NULL) != 0)
+                       break;
        t = ip6t_get_target(e);
 
        par.net      = net;
@@ -1090,13 +1105,16 @@ static int compat_calc_entry(const struct ip6t_entry *e,
                             const struct xt_table_info *info,
                             const void *base, struct xt_table_info *newinfo)
 {
+       const struct xt_entry_match *ematch;
        const struct ip6t_entry_target *t;
        unsigned int entry_offset;
        int off, i, ret;
 
        off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
        entry_offset = (void *)e - base;
-       IP6T_MATCH_ITERATE(e, compat_calc_match, &off);
+       xt_ematch_foreach(ematch, e)
+               if (compat_calc_match(ematch, &off) != 0)
+                       break;
        t = ip6t_get_target_c(e);
        off += xt_compat_target_offset(t->u.kernel.target);
        newinfo->size -= off;
@@ -1474,7 +1492,8 @@ compat_copy_entry_to_user(struct ip6t_entry *e, void __user **dstptr,
        struct compat_ip6t_entry __user *ce;
        u_int16_t target_offset, next_offset;
        compat_uint_t origsize;
-       int ret;
+       const struct xt_entry_match *ematch;
+       int ret = 0;
 
        origsize = *size;
        ce = (struct compat_ip6t_entry __user *)*dstptr;
@@ -1486,7 +1505,11 @@ compat_copy_entry_to_user(struct ip6t_entry *e, void __user **dstptr,
        *dstptr += sizeof(struct compat_ip6t_entry);
        *size -= sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
 
-       ret = IP6T_MATCH_ITERATE(e, xt_compat_match_to_user, dstptr, size);
+       xt_ematch_foreach(ematch, e) {
+               ret = xt_compat_match_to_user(ematch, dstptr, size);
+               if (ret != 0)
+                       break;
+       }
        target_offset = e->target_offset - (origsize - *size);
        if (ret)
                return ret;
@@ -1538,9 +1561,12 @@ compat_release_match(struct ip6t_entry_match *m, unsigned int *i)
 static void compat_release_entry(struct compat_ip6t_entry *e)
 {
        struct ip6t_entry_target *t;
+       struct xt_entry_match *ematch;
 
        /* Cleanup all matches */
-       COMPAT_IP6T_MATCH_ITERATE(e, compat_release_match, NULL);
+       xt_ematch_foreach(ematch, e)
+               if (compat_release_match(ematch, NULL) != 0)
+                       break;
        t = compat_ip6t_get_target(e);
        module_put(t->u.kernel.target->me);
 }
@@ -1555,6 +1581,7 @@ check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
                                  const unsigned int *underflows,
                                  const char *name)
 {
+       struct xt_entry_match *ematch;
        struct ip6t_entry_target *t;
        struct xt_target *target;
        unsigned int entry_offset;
@@ -1583,8 +1610,12 @@ check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
        off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
        entry_offset = (void *)e - (void *)base;
        j = 0;
-       ret = COMPAT_IP6T_MATCH_ITERATE(e, compat_find_calc_match, name,
-                                       &e->ipv6, e->comefrom, &off, &j);
+       xt_ematch_foreach(ematch, e) {
+               ret = compat_find_calc_match(ematch, name,
+                     &e->ipv6, e->comefrom, &off, &j);
+               if (ret != 0)
+                       break;
+       }
        if (ret != 0)
                goto release_matches;
 
@@ -1623,7 +1654,9 @@ check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
 out:
        module_put(t->u.kernel.target->me);
 release_matches:
-       IP6T_MATCH_ITERATE(e, compat_release_match, &j);
+       xt_ematch_foreach(ematch, e)
+               if (compat_release_match(ematch, &j) != 0)
+                       break;
        return ret;
 }
 
@@ -1637,6 +1670,7 @@ compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr,
        struct ip6t_entry *de;
        unsigned int origsize;
        int ret, h;
+       struct xt_entry_match *ematch;
 
        ret = 0;
        origsize = *size;
@@ -1647,8 +1681,11 @@ compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr,
        *dstptr += sizeof(struct ip6t_entry);
        *size += sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
 
-       ret = COMPAT_IP6T_MATCH_ITERATE(e, xt_compat_match_from_user,
-                                       dstptr, size);
+       xt_ematch_foreach(ematch, e) {
+               ret = xt_compat_match_from_user(ematch, dstptr, size);
+               if (ret != 0)
+                       break;
+       }
        if (ret)
                return ret;
        de->target_offset = e->target_offset - (origsize - *size);
@@ -1670,8 +1707,9 @@ static int compat_check_entry(struct ip6t_entry *e, struct net *net,
                              const char *name)
 {
        unsigned int j;
-       int ret;
+       int ret = 0;
        struct xt_mtchk_param mtpar;
+       struct xt_entry_match *ematch;
 
        j = 0;
        mtpar.net       = net;
@@ -1679,7 +1717,11 @@ static int compat_check_entry(struct ip6t_entry *e, struct net *net,
        mtpar.entryinfo = &e->ipv6;
        mtpar.hook_mask = e->comefrom;
        mtpar.family    = NFPROTO_IPV6;
-       ret = IP6T_MATCH_ITERATE(e, check_match, &mtpar, &j);
+       xt_ematch_foreach(ematch, e) {
+               ret = check_match(ematch, &mtpar, &j);
+               if (ret != 0)
+                       break;
+       }
        if (ret)
                goto cleanup_matches;
 
@@ -1689,7 +1731,9 @@ static int compat_check_entry(struct ip6t_entry *e, struct net *net,
        return 0;
 
  cleanup_matches:
-       IP6T_MATCH_ITERATE(e, cleanup_match, net, &j);
+       xt_ematch_foreach(ematch, e)
+               if (cleanup_match(ematch, net, &j) != 0)
+                       break;
        return ret;
 }
 

diff --git a/net/netfilter/xt_TCPMSS.c b/net/netfilter/xt_TCPMSS.c
index 6f21b43..0e357ac 100644 (file)
--- a/net/netfilter/xt_TCPMSS.c
+++ b/net/netfilter/xt_TCPMSS.c
@@ -239,6 +239,7 @@ static bool tcpmss_tg4_check(const struct xt_tgchk_param *par)
 {
        const struct xt_tcpmss_info *info = par->targinfo;
        const struct ipt_entry *e = par->entryinfo;
+       const struct xt_entry_match *ematch;
 
        if (info->mss == XT_TCPMSS_CLAMP_PMTU &&
            (par->hook_mask & ~((1 << NF_INET_FORWARD) |
@@ -248,8 +249,9 @@ static bool tcpmss_tg4_check(const struct xt_tgchk_param *par)
                       "FORWARD, OUTPUT and POSTROUTING hooks\n");
                return false;
        }
-       if (IPT_MATCH_ITERATE(e, find_syn_match))
-               return true;
+       xt_ematch_foreach(ematch, e)
+               if (find_syn_match(ematch))
+                       return true;
        printk("xt_TCPMSS: Only works on TCP SYN packets\n");
        return false;
 }
@@ -259,6 +261,7 @@ static bool tcpmss_tg6_check(const struct xt_tgchk_param *par)
 {
        const struct xt_tcpmss_info *info = par->targinfo;
        const struct ip6t_entry *e = par->entryinfo;
+       const struct xt_entry_match *ematch;
 
        if (info->mss == XT_TCPMSS_CLAMP_PMTU &&
            (par->hook_mask & ~((1 << NF_INET_FORWARD) |
@@ -268,8 +271,9 @@ static bool tcpmss_tg6_check(const struct xt_tgchk_param *par)
                       "FORWARD, OUTPUT and POSTROUTING hooks\n");
                return false;
        }
-       if (IP6T_MATCH_ITERATE(e, find_syn_match))
-               return true;
+       xt_ematch_foreach(ematch, e)
+               if (find_syn_match(ematch))
+                       return true;
        printk("xt_TCPMSS: Only works on TCP SYN packets\n");
        return false;
 }