netfilter: xtables: optimize call flow around xt_ematch_foreach

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

diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 3a7fc732b918ae886441479eda39053e6f095570..36edc7d5f28472a71a93b05d9569d819ee92be07 100644 (file)
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -572,14 +572,10 @@ mark_source_chains(const struct xt_table_info *newinfo,
        return 1;
 }
 
-static int
-cleanup_match(struct ipt_entry_match *m, struct net *net, unsigned int *i)
+static void cleanup_match(struct ipt_entry_match *m, struct net *net)
 {
        struct xt_mtdtor_param par;
 
-       if (i && (*i)-- == 0)
-               return 1;
-
        par.net       = net;
        par.match     = m->u.kernel.match;
        par.matchinfo = m->data;
@@ -587,7 +583,6 @@ cleanup_match(struct ipt_entry_match *m, struct net *net, unsigned int *i)
        if (par.match->destroy != NULL)
                par.match->destroy(&par);
        module_put(par.match->me);
-       return 0;
 }
 
 static int
@@ -612,8 +607,7 @@ check_entry(const struct ipt_entry *e, const char *name)
 }
 
 static int
-check_match(struct ipt_entry_match *m, struct xt_mtchk_param *par,
-           unsigned int *i)
+check_match(struct ipt_entry_match *m, struct xt_mtchk_param *par)
 {
        const struct ipt_ip *ip = par->entryinfo;
        int ret;
@@ -628,13 +622,11 @@ check_match(struct ipt_entry_match *m, struct xt_mtchk_param *par,
                         par.match->name);
                return ret;
        }
-       ++*i;
        return 0;
 }
 
 static int
-find_check_match(struct ipt_entry_match *m, struct xt_mtchk_param *par,
-                unsigned int *i)
+find_check_match(struct ipt_entry_match *m, struct xt_mtchk_param *par)
 {
        struct xt_match *match;
        int ret;
@@ -648,7 +640,7 @@ find_check_match(struct ipt_entry_match *m, struct xt_mtchk_param *par,
        }
        m->u.kernel.match = match;
 
-       ret = check_match(m, par, i);
+       ret = check_match(m, par);
        if (ret)
                goto err;
 
@@ -704,12 +696,11 @@ find_check_entry(struct ipt_entry *e, struct net *net, const char *name,
        mtpar.hook_mask = e->comefrom;
        mtpar.family    = NFPROTO_IPV4;
        xt_ematch_foreach(ematch, e) {
-               ret = find_check_match(ematch, &mtpar, &j);
+               ret = find_check_match(ematch, &mtpar);
                if (ret != 0)
-                       break;
+                       goto cleanup_matches;
+               ++j;
        }
-       if (ret != 0)
-               goto cleanup_matches;
 
        t = ipt_get_target(e);
        target = try_then_request_module(xt_find_target(AF_INET,
@@ -730,9 +721,11 @@ find_check_entry(struct ipt_entry *e, struct net *net, const char *name,
  err:
        module_put(t->u.kernel.target->me);
  cleanup_matches:
-       xt_ematch_foreach(ematch, e)
-               if (cleanup_match(ematch, net, &j) != 0)
+       xt_ematch_foreach(ematch, e) {
+               if (j-- == 0)
                        break;
+               cleanup_match(ematch, net);
+       }
        return ret;
 }
 
@@ -807,8 +800,7 @@ cleanup_entry(struct ipt_entry *e, struct net *net)
 
        /* Cleanup all matches */
        xt_ematch_foreach(ematch, e)
-               if (cleanup_match(ematch, net, NULL) != 0)
-                       break;
+               cleanup_match(ematch, net);
        t = ipt_get_target(e);
 
        par.net      = net;
@@ -1064,13 +1056,6 @@ static int compat_standard_to_user(void __user *dst, const void *src)
        return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
 }
 
-static inline int
-compat_calc_match(const struct ipt_entry_match *m, int *size)
-{
-       *size += xt_compat_match_offset(m->u.kernel.match);
-       return 0;
-}
-
 static int compat_calc_entry(const struct ipt_entry *e,
                             const struct xt_table_info *info,
                             const void *base, struct xt_table_info *newinfo)
@@ -1083,8 +1068,7 @@ static int compat_calc_entry(const struct ipt_entry *e,
        off = sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
        entry_offset = (void *)e - base;
        xt_ematch_foreach(ematch, e)
-               if (compat_calc_match(ematch, &off) != 0)
-                       break;
+               off += xt_compat_match_offset(ematch->u.kernel.match);
        t = ipt_get_target_c(e);
        off += xt_compat_target_offset(t->u.kernel.target);
        newinfo->size -= off;
@@ -1475,11 +1459,9 @@ compat_copy_entry_to_user(struct ipt_entry *e, void __user **dstptr,
        xt_ematch_foreach(ematch, e) {
                ret = xt_compat_match_to_user(ematch, dstptr, size);
                if (ret != 0)
-                       break;
+                       return ret;
        }
        target_offset = e->target_offset - (origsize - *size);
-       if (ret)
-               return ret;
        t = ipt_get_target(e);
        ret = xt_compat_target_to_user(t, dstptr, size);
        if (ret)
@@ -1496,7 +1478,7 @@ compat_find_calc_match(struct ipt_entry_match *m,
                       const char *name,
                       const struct ipt_ip *ip,
                       unsigned int hookmask,
-                      int *size, unsigned int *i)
+                      int *size)
 {
        struct xt_match *match;
 
@@ -1510,18 +1492,6 @@ compat_find_calc_match(struct ipt_entry_match *m,
        }
        m->u.kernel.match = match;
        *size += xt_compat_match_offset(match);
-
-       (*i)++;
-       return 0;
-}
-
-static int
-compat_release_match(struct ipt_entry_match *m, unsigned int *i)
-{
-       if (i && (*i)-- == 0)
-               return 1;
-
-       module_put(m->u.kernel.match->me);
        return 0;
 }
 
@@ -1532,8 +1502,7 @@ static void compat_release_entry(struct compat_ipt_entry *e)
 
        /* Cleanup all matches */
        xt_ematch_foreach(ematch, e)
-               if (compat_release_match(ematch, NULL) != 0)
-                       break;
+               module_put(ematch->u.kernel.match->me);
        t = compat_ipt_get_target(e);
        module_put(t->u.kernel.target->me);
 }
@@ -1579,12 +1548,11 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
        j = 0;
        xt_ematch_foreach(ematch, e) {
                ret = compat_find_calc_match(ematch, name,
-                     &e->ip, e->comefrom, &off, &j);
+                     &e->ip, e->comefrom, &off);
                if (ret != 0)
-                       break;
+                       goto release_matches;
+               ++j;
        }
-       if (ret != 0)
-               goto release_matches;
 
        t = compat_ipt_get_target(e);
        target = try_then_request_module(xt_find_target(AF_INET,
@@ -1621,9 +1589,11 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
 out:
        module_put(t->u.kernel.target->me);
 release_matches:
-       xt_ematch_foreach(ematch, e)
-               if (compat_release_match(ematch, &j) != 0)
+       xt_ematch_foreach(ematch, e) {
+               if (j-- == 0)
                        break;
+               module_put(ematch->u.kernel.match->me);
+       }
        return ret;
 }
 
@@ -1651,10 +1621,8 @@ compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr,
        xt_ematch_foreach(ematch, e) {
                ret = xt_compat_match_from_user(ematch, dstptr, size);
                if (ret != 0)
-                       break;
+                       return ret;
        }
-       if (ret)
-               return ret;
        de->target_offset = e->target_offset - (origsize - *size);
        t = compat_ipt_get_target(e);
        target = t->u.kernel.target;
@@ -1685,12 +1653,11 @@ compat_check_entry(struct ipt_entry *e, struct net *net, const char *name)
        mtpar.hook_mask = e->comefrom;
        mtpar.family    = NFPROTO_IPV4;
        xt_ematch_foreach(ematch, e) {
-               ret = check_match(ematch, &mtpar, &j);
+               ret = check_match(ematch, &mtpar);
                if (ret != 0)
-                       break;
+                       goto cleanup_matches;
+               ++j;
        }
-       if (ret)
-               goto cleanup_matches;
 
        ret = check_target(e, net, name);
        if (ret)
@@ -1698,9 +1665,11 @@ compat_check_entry(struct ipt_entry *e, struct net *net, const char *name)
        return 0;
 
  cleanup_matches:
-       xt_ematch_foreach(ematch, e)
-               if (cleanup_match(ematch, net, &j) != 0)
+       xt_ematch_foreach(ematch, e) {
+               if (j-- == 0)
                        break;
+               cleanup_match(ematch, net);
+       }
        return ret;
 }
 

diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index 1537e6bad5d99ff6d3c104fdb360ff850fe4f1dd..c5a963e4b545a6bb5e787bf3047dee61034a0ef3 100644 (file)
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -603,14 +603,10 @@ mark_source_chains(const struct xt_table_info *newinfo,
        return 1;
 }
 
-static int
-cleanup_match(struct ip6t_entry_match *m, struct net *net, unsigned int *i)
+static void cleanup_match(struct ip6t_entry_match *m, struct net *net)
 {
        struct xt_mtdtor_param par;
 
-       if (i && (*i)-- == 0)
-               return 1;
-
        par.net       = net;
        par.match     = m->u.kernel.match;
        par.matchinfo = m->data;
@@ -618,7 +614,6 @@ cleanup_match(struct ip6t_entry_match *m, struct net *net, unsigned int *i)
        if (par.match->destroy != NULL)
                par.match->destroy(&par);
        module_put(par.match->me);
-       return 0;
 }
 
 static int
@@ -642,8 +637,7 @@ check_entry(const struct ip6t_entry *e, const char *name)
        return 0;
 }
 
-static int check_match(struct ip6t_entry_match *m, struct xt_mtchk_param *par,
-                      unsigned int *i)
+static int check_match(struct ip6t_entry_match *m, struct xt_mtchk_param *par)
 {
        const struct ip6t_ip6 *ipv6 = par->entryinfo;
        int ret;
@@ -658,13 +652,11 @@ static int check_match(struct ip6t_entry_match *m, struct xt_mtchk_param *par,
                         par.match->name);
                return ret;
        }
-       ++*i;
        return 0;
 }
 
 static int
-find_check_match(struct ip6t_entry_match *m, struct xt_mtchk_param *par,
-                unsigned int *i)
+find_check_match(struct ip6t_entry_match *m, struct xt_mtchk_param *par)
 {
        struct xt_match *match;
        int ret;
@@ -678,7 +670,7 @@ find_check_match(struct ip6t_entry_match *m, struct xt_mtchk_param *par,
        }
        m->u.kernel.match = match;
 
-       ret = check_match(m, par, i);
+       ret = check_match(m, par);
        if (ret)
                goto err;
 
@@ -735,12 +727,11 @@ find_check_entry(struct ip6t_entry *e, struct net *net, const char *name,
        mtpar.hook_mask = e->comefrom;
        mtpar.family    = NFPROTO_IPV6;
        xt_ematch_foreach(ematch, e) {
-               ret = find_check_match(ematch, &mtpar, &j);
+               ret = find_check_match(ematch, &mtpar);
                if (ret != 0)
-                       break;
+                       goto cleanup_matches;
+               ++j;
        }
-       if (ret != 0)
-               goto cleanup_matches;
 
        t = ip6t_get_target(e);
        target = try_then_request_module(xt_find_target(AF_INET6,
@@ -761,9 +752,11 @@ find_check_entry(struct ip6t_entry *e, struct net *net, const char *name,
  err:
        module_put(t->u.kernel.target->me);
  cleanup_matches:
-       xt_ematch_foreach(ematch, e)
-               if (cleanup_match(ematch, net, &j) != 0)
+       xt_ematch_foreach(ematch, e) {
+               if (j-- == 0)
                        break;
+               cleanup_match(ematch, net);
+       }
        return ret;
 }
 
@@ -837,8 +830,7 @@ static void cleanup_entry(struct ip6t_entry *e, struct net *net)
 
        /* Cleanup all matches */
        xt_ematch_foreach(ematch, e)
-               if (cleanup_match(ematch, net, NULL) != 0)
-                       break;
+               cleanup_match(ematch, net);
        t = ip6t_get_target(e);
 
        par.net      = net;
@@ -1094,13 +1086,6 @@ static int compat_standard_to_user(void __user *dst, const void *src)
        return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
 }
 
-static inline int
-compat_calc_match(const struct ip6t_entry_match *m, int *size)
-{
-       *size += xt_compat_match_offset(m->u.kernel.match);
-       return 0;
-}
-
 static int compat_calc_entry(const struct ip6t_entry *e,
                             const struct xt_table_info *info,
                             const void *base, struct xt_table_info *newinfo)
@@ -1113,8 +1098,7 @@ static int compat_calc_entry(const struct ip6t_entry *e,
        off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
        entry_offset = (void *)e - base;
        xt_ematch_foreach(ematch, e)
-               if (compat_calc_match(ematch, &off) != 0)
-                       break;
+               off += xt_compat_match_offset(ematch->u.kernel.match);
        t = ip6t_get_target_c(e);
        off += xt_compat_target_offset(t->u.kernel.target);
        newinfo->size -= off;
@@ -1508,11 +1492,9 @@ compat_copy_entry_to_user(struct ip6t_entry *e, void __user **dstptr,
        xt_ematch_foreach(ematch, e) {
                ret = xt_compat_match_to_user(ematch, dstptr, size);
                if (ret != 0)
-                       break;
+                       return ret;
        }
        target_offset = e->target_offset - (origsize - *size);
-       if (ret)
-               return ret;
        t = ip6t_get_target(e);
        ret = xt_compat_target_to_user(t, dstptr, size);
        if (ret)
@@ -1529,7 +1511,7 @@ compat_find_calc_match(struct ip6t_entry_match *m,
                       const char *name,
                       const struct ip6t_ip6 *ipv6,
                       unsigned int hookmask,
-                      int *size, unsigned int *i)
+                      int *size)
 {
        struct xt_match *match;
 
@@ -1543,18 +1525,6 @@ compat_find_calc_match(struct ip6t_entry_match *m,
        }
        m->u.kernel.match = match;
        *size += xt_compat_match_offset(match);
-
-       (*i)++;
-       return 0;
-}
-
-static int
-compat_release_match(struct ip6t_entry_match *m, unsigned int *i)
-{
-       if (i && (*i)-- == 0)
-               return 1;
-
-       module_put(m->u.kernel.match->me);
        return 0;
 }
 
@@ -1565,8 +1535,7 @@ static void compat_release_entry(struct compat_ip6t_entry *e)
 
        /* Cleanup all matches */
        xt_ematch_foreach(ematch, e)
-               if (compat_release_match(ematch, NULL) != 0)
-                       break;
+               module_put(ematch->u.kernel.match->me);
        t = compat_ip6t_get_target(e);
        module_put(t->u.kernel.target->me);
 }
@@ -1612,12 +1581,11 @@ check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
        j = 0;
        xt_ematch_foreach(ematch, e) {
                ret = compat_find_calc_match(ematch, name,
-                     &e->ipv6, e->comefrom, &off, &j);
+                     &e->ipv6, e->comefrom, &off);
                if (ret != 0)
-                       break;
+                       goto release_matches;
+               ++j;
        }
-       if (ret != 0)
-               goto release_matches;
 
        t = compat_ip6t_get_target(e);
        target = try_then_request_module(xt_find_target(AF_INET6,
@@ -1654,9 +1622,11 @@ check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
 out:
        module_put(t->u.kernel.target->me);
 release_matches:
-       xt_ematch_foreach(ematch, e)
-               if (compat_release_match(ematch, &j) != 0)
+       xt_ematch_foreach(ematch, e) {
+               if (j-- == 0)
                        break;
+               module_put(ematch->u.kernel.match->me);
+       }
        return ret;
 }
 
@@ -1684,10 +1654,8 @@ compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr,
        xt_ematch_foreach(ematch, e) {
                ret = xt_compat_match_from_user(ematch, dstptr, size);
                if (ret != 0)
-                       break;
+                       return ret;
        }
-       if (ret)
-               return ret;
        de->target_offset = e->target_offset - (origsize - *size);
        t = compat_ip6t_get_target(e);
        target = t->u.kernel.target;
@@ -1718,12 +1686,11 @@ static int compat_check_entry(struct ip6t_entry *e, struct net *net,
        mtpar.hook_mask = e->comefrom;
        mtpar.family    = NFPROTO_IPV6;
        xt_ematch_foreach(ematch, e) {
-               ret = check_match(ematch, &mtpar, &j);
+               ret = check_match(ematch, &mtpar);
                if (ret != 0)
-                       break;
+                       goto cleanup_matches;
+               ++j;
        }
-       if (ret)
-               goto cleanup_matches;
 
        ret = check_target(e, net, name);
        if (ret)
@@ -1731,9 +1698,11 @@ static int compat_check_entry(struct ip6t_entry *e, struct net *net,
        return 0;
 
  cleanup_matches:
-       xt_ematch_foreach(ematch, e)
-               if (cleanup_match(ematch, net, &j) != 0)
+       xt_ematch_foreach(ematch, e) {
+               if (j-- == 0)
                        break;
+               cleanup_match(ematch, net);
+       }
        return ret;
 }