netfilter: xtables: mark initial tables constant

The inputted table is never modified, so should be considered const.

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

22 files changed, 42 insertions, 37 deletions

diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h
index 4fa6e4c263e0..812cb153cabb 100644
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -407,7 +407,7 @@ extern int xt_check_target(struct xt_tgchk_param *,
                            unsigned int size, u_int8_t proto, bool inv_proto);
 
 extern struct xt_table *xt_register_table(struct net *net,
-                                          struct xt_table *table,
+                                          const struct xt_table *table,
                                           struct xt_table_info *bootstrap,
                                           struct xt_table_info *newinfo);
 extern void *xt_unregister_table(struct xt_table *table);
diff --git a/include/linux/netfilter_arp/arp_tables.h b/include/linux/netfilter_arp/arp_tables.h
index 590ac3d6d5d6..6fe3e6aa10db 100644
--- a/include/linux/netfilter_arp/arp_tables.h
+++ b/include/linux/netfilter_arp/arp_tables.h
@@ -265,7 +265,7 @@ struct arpt_error
 }
 
 extern struct xt_table *arpt_register_table(struct net *net,
-                                            struct xt_table *table,
+                                            const struct xt_table *table,
                                             const struct arpt_replace *repl);
 extern void arpt_unregister_table(struct xt_table *table);
 extern unsigned int arpt_do_table(struct sk_buff *skb,
diff --git a/include/linux/netfilter_bridge/ebtables.h b/include/linux/netfilter_bridge/ebtables.h
index e40ddb94b1af..ea281e6a2048 100644
--- a/include/linux/netfilter_bridge/ebtables.h
+++ b/include/linux/netfilter_bridge/ebtables.h
@@ -301,7 +301,7 @@ struct ebt_table
 #define EBT_ALIGN(s) (((s) + (__alignof__(struct ebt_replace)-1)) & \
                      ~(__alignof__(struct ebt_replace)-1))
 extern struct ebt_table *ebt_register_table(struct net *net,
-                                            struct ebt_table *table);
+                                            const struct ebt_table *table);
 extern void ebt_unregister_table(struct ebt_table *table);
 extern unsigned int ebt_do_table(unsigned int hook, struct sk_buff *skb,
    const struct net_device *in, const struct net_device *out,
diff --git a/include/linux/netfilter_ipv4/ip_tables.h b/include/linux/netfilter_ipv4/ip_tables.h
index 092bd50581a9..61fafc868a7b 100644
--- a/include/linux/netfilter_ipv4/ip_tables.h
+++ b/include/linux/netfilter_ipv4/ip_tables.h
@@ -245,7 +245,7 @@ ipt_get_target(struct ipt_entry *e)
 extern void ipt_init(void) __init;
 
 extern struct xt_table *ipt_register_table(struct net *net,
-                                           struct xt_table *table,
+                                           const struct xt_table *table,
                                            const struct ipt_replace *repl);
 extern void ipt_unregister_table(struct xt_table *table);
 
diff --git a/include/linux/netfilter_ipv6/ip6_tables.h b/include/linux/netfilter_ipv6/ip6_tables.h
index 1089e33cf633..a64e1451ac38 100644
--- a/include/linux/netfilter_ipv6/ip6_tables.h
+++ b/include/linux/netfilter_ipv6/ip6_tables.h
@@ -306,7 +306,7 @@ ip6t_get_target(struct ip6t_entry *e)
 extern void ip6t_init(void) __init;
 
 extern struct xt_table *ip6t_register_table(struct net *net,
-                                            struct xt_table *table,
+                                            const struct xt_table *table,
                                             const struct ip6t_replace *repl);
 extern void ip6t_unregister_table(struct xt_table *table);
 extern unsigned int ip6t_do_table(struct sk_buff *skb,
diff --git a/net/bridge/netfilter/ebtable_broute.c b/net/bridge/netfilter/ebtable_broute.c
index c751111440f8..d32ab13e728c 100644
--- a/net/bridge/netfilter/ebtable_broute.c
+++ b/net/bridge/netfilter/ebtable_broute.c
@@ -41,7 +41,7 @@ static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
         return 0;
 }
 
-static struct ebt_table broute_table =
+static const struct ebt_table broute_table =
 {
         .name           = "broute",
         .table          = &initial_table,
diff --git a/net/bridge/netfilter/ebtable_filter.c b/net/bridge/netfilter/ebtable_filter.c
index 4b988db3cd4d..60b1a6ca7185 100644
--- a/net/bridge/netfilter/ebtable_filter.c
+++ b/net/bridge/netfilter/ebtable_filter.c
@@ -50,7 +50,7 @@ static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
         return 0;
 }
 
-static struct ebt_table frame_filter =
+static const struct ebt_table frame_filter =
 {
         .name           = "filter",
         .table          = &initial_table,
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 37928d5f2840..bd1c65425d4f 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1103,23 +1103,24 @@ free_newinfo:
         return ret;
 }
 
-struct ebt_table *ebt_register_table(struct net *net, struct ebt_table *table)
+struct ebt_table *
+ebt_register_table(struct net *net, const struct ebt_table *input_table)
 {
         struct ebt_table_info *newinfo;
-        struct ebt_table *t;
+        struct ebt_table *t, *table;
         struct ebt_replace_kernel *repl;
         int ret, i, countersize;
         void *p;
 
-        if (!table || !(repl = table->table) || !repl->entries ||
-            repl->entries_size == 0 ||
-            repl->counters || table->private) {
+        if (input_table == NULL || (repl = input_table->table) == NULL ||
+            repl->entries == 0 || repl->entries_size == 0 ||
+            repl->counters != NULL || input_table->private != NULL) {
                 BUGPRINT("Bad table data for ebt_register_table!!!\n");
                 return ERR_PTR(-EINVAL);
         }
 
         /* Don't add one table to multiple lists. */
-        table = kmemdup(table, sizeof(struct ebt_table), GFP_KERNEL);
+        table = kmemdup(input_table, sizeof(struct ebt_table), GFP_KERNEL);
         if (!table) {
                 ret = -ENOMEM;
                 goto out;
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 7bc11ffbb845..27774c99d888 100644
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -1778,7 +1778,8 @@ static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len
         return ret;
 }
 
-struct xt_table *arpt_register_table(struct net *net, struct xt_table *table,
+struct xt_table *arpt_register_table(struct net *net,
+                                     const struct xt_table *table,
                                      const struct arpt_replace *repl)
 {
         int ret;
diff --git a/net/ipv4/netfilter/arptable_filter.c b/net/ipv4/netfilter/arptable_filter.c
index 6ecfdae7c589..97337601827a 100644
--- a/net/ipv4/netfilter/arptable_filter.c
+++ b/net/ipv4/netfilter/arptable_filter.c
@@ -15,7 +15,7 @@ MODULE_DESCRIPTION("arptables filter table");
 #define FILTER_VALID_HOOKS ((1 << NF_ARP_IN) | (1 << NF_ARP_OUT) | \
                            (1 << NF_ARP_FORWARD))
 
-static struct
+static const struct
 {
         struct arpt_replace repl;
         struct arpt_standard entries[3];
@@ -45,7 +45,7 @@ static struct
         .term = ARPT_ERROR_INIT,
 };
 
-static struct xt_table packet_filter = {
+static const struct xt_table packet_filter = {
         .name           = "filter",
         .valid_hooks    = FILTER_VALID_HOOKS,
         .me             = THIS_MODULE,
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 0b43fd7ca04a..cde755d5eeab 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -2065,7 +2065,8 @@ do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
         return ret;
 }
 
-struct xt_table *ipt_register_table(struct net *net, struct xt_table *table,
+struct xt_table *ipt_register_table(struct net *net,
+                                    const struct xt_table *table,
                                     const struct ipt_replace *repl)
 {
         int ret;
diff --git a/net/ipv4/netfilter/iptable_filter.c b/net/ipv4/netfilter/iptable_filter.c
index 97dbd94a8e37..df566cbd68e5 100644
--- a/net/ipv4/netfilter/iptable_filter.c
+++ b/net/ipv4/netfilter/iptable_filter.c
@@ -53,7 +53,7 @@ static struct
         .term = IPT_ERROR_INIT,                 /* ERROR */
 };
 
-static struct xt_table packet_filter = {
+static const struct xt_table packet_filter = {
         .name           = "filter",
         .valid_hooks    = FILTER_VALID_HOOKS,
         .me             = THIS_MODULE,
diff --git a/net/ipv4/netfilter/iptable_mangle.c b/net/ipv4/netfilter/iptable_mangle.c
index 28647f10aa7e..036047f9b0f2 100644
--- a/net/ipv4/netfilter/iptable_mangle.c
+++ b/net/ipv4/netfilter/iptable_mangle.c
@@ -28,7 +28,7 @@ MODULE_DESCRIPTION("iptables mangle table");
                             (1 << NF_INET_POST_ROUTING))
 
 /* Ouch - five different hooks? Maybe this should be a config option..... -- BC */
-static struct
+static const struct
 {
         struct ipt_replace repl;
         struct ipt_standard entries[5];
@@ -64,7 +64,7 @@ static struct
         .term = IPT_ERROR_INIT,                 /* ERROR */
 };
 
-static struct xt_table packet_mangler = {
+static const struct xt_table packet_mangler = {
         .name           = "mangle",
         .valid_hooks    = MANGLE_VALID_HOOKS,
         .me             = THIS_MODULE,
diff --git a/net/ipv4/netfilter/iptable_raw.c b/net/ipv4/netfilter/iptable_raw.c
index 494784c999eb..993edc23be09 100644
--- a/net/ipv4/netfilter/iptable_raw.c
+++ b/net/ipv4/netfilter/iptable_raw.c
@@ -9,7 +9,7 @@
 
 #define RAW_VALID_HOOKS ((1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_OUT))
 
-static struct
+static const struct
 {
         struct ipt_replace repl;
         struct ipt_standard entries[2];
@@ -36,7 +36,7 @@ static struct
         .term = IPT_ERROR_INIT,                 /* ERROR */
 };
 
-static struct xt_table packet_raw = {
+static const struct xt_table packet_raw = {
         .name = "raw",
         .valid_hooks =  RAW_VALID_HOOKS,
         .me = THIS_MODULE,
diff --git a/net/ipv4/netfilter/iptable_security.c b/net/ipv4/netfilter/iptable_security.c
index 8804e1a0f915..99eb76c65d25 100644
--- a/net/ipv4/netfilter/iptable_security.c
+++ b/net/ipv4/netfilter/iptable_security.c
@@ -27,7 +27,7 @@ MODULE_DESCRIPTION("iptables security table, for MAC rules");
                                 (1 << NF_INET_FORWARD) | \
                                 (1 << NF_INET_LOCAL_OUT)
 
-static struct
+static const struct
 {
         struct ipt_replace repl;
         struct ipt_standard entries[3];
@@ -57,7 +57,7 @@ static struct
         .term = IPT_ERROR_INIT,                 /* ERROR */
 };
 
-static struct xt_table security_table = {
+static const struct xt_table security_table = {
         .name           = "security",
         .valid_hooks    = SECURITY_VALID_HOOKS,
         .me             = THIS_MODULE,
diff --git a/net/ipv4/netfilter/nf_nat_rule.c b/net/ipv4/netfilter/nf_nat_rule.c
index 6448a9b7d6f0..9e81e0dfb4ec 100644
--- a/net/ipv4/netfilter/nf_nat_rule.c
+++ b/net/ipv4/netfilter/nf_nat_rule.c
@@ -28,7 +28,7 @@
                          (1 << NF_INET_POST_ROUTING) | \
                          (1 << NF_INET_LOCAL_OUT))
 
-static struct
+static const struct
 {
         struct ipt_replace repl;
         struct ipt_standard entries[3];
@@ -58,7 +58,7 @@ static struct
         .term = IPT_ERROR_INIT,                 /* ERROR */
 };
 
-static struct xt_table nat_table = {
+static const struct xt_table nat_table = {
         .name           = "nat",
         .valid_hooks    = NAT_VALID_HOOKS,
         .me             = THIS_MODULE,
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index a5d0c27cc26f..cc9f8ef303fd 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -2100,7 +2100,8 @@ do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
         return ret;
 }
 
-struct xt_table *ip6t_register_table(struct net *net, struct xt_table *table,
+struct xt_table *ip6t_register_table(struct net *net,
+                                     const struct xt_table *table,
                                      const struct ip6t_replace *repl)
 {
         int ret;
diff --git a/net/ipv6/netfilter/ip6table_filter.c b/net/ipv6/netfilter/ip6table_filter.c
index 0a3ae48ac4d5..6f4383ad86f9 100644
--- a/net/ipv6/netfilter/ip6table_filter.c
+++ b/net/ipv6/netfilter/ip6table_filter.c
@@ -51,7 +51,7 @@ static struct
         .term = IP6T_ERROR_INIT,                /* ERROR */
 };
 
-static struct xt_table packet_filter = {
+static const struct xt_table packet_filter = {
         .name           = "filter",
         .valid_hooks    = FILTER_VALID_HOOKS,
         .me             = THIS_MODULE,
diff --git a/net/ipv6/netfilter/ip6table_mangle.c b/net/ipv6/netfilter/ip6table_mangle.c
index 0f49e005a8c5..0ad91433ed61 100644
--- a/net/ipv6/netfilter/ip6table_mangle.c
+++ b/net/ipv6/netfilter/ip6table_mangle.c
@@ -21,7 +21,7 @@ MODULE_DESCRIPTION("ip6tables mangle table");
                             (1 << NF_INET_LOCAL_OUT) | \
                             (1 << NF_INET_POST_ROUTING))
 
-static struct
+static const struct
 {
         struct ip6t_replace repl;
         struct ip6t_standard entries[5];
@@ -57,7 +57,7 @@ static struct
         .term = IP6T_ERROR_INIT,                /* ERROR */
 };
 
-static struct xt_table packet_mangler = {
+static const struct xt_table packet_mangler = {
         .name           = "mangle",
         .valid_hooks    = MANGLE_VALID_HOOKS,
         .me             = THIS_MODULE,
diff --git a/net/ipv6/netfilter/ip6table_raw.c b/net/ipv6/netfilter/ip6table_raw.c
index 679865e3d5ff..ed1a1180f3b3 100644
--- a/net/ipv6/netfilter/ip6table_raw.c
+++ b/net/ipv6/netfilter/ip6table_raw.c
@@ -8,7 +8,7 @@
 
 #define RAW_VALID_HOOKS ((1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_OUT))
 
-static struct
+static const struct
 {
         struct ip6t_replace repl;
         struct ip6t_standard entries[2];
@@ -35,7 +35,7 @@ static struct
         .term = IP6T_ERROR_INIT,                /* ERROR */
 };
 
-static struct xt_table packet_raw = {
+static const struct xt_table packet_raw = {
         .name = "raw",
         .valid_hooks = RAW_VALID_HOOKS,
         .me = THIS_MODULE,
diff --git a/net/ipv6/netfilter/ip6table_security.c b/net/ipv6/netfilter/ip6table_security.c
index 822afabbdc88..41b444c60934 100644
--- a/net/ipv6/netfilter/ip6table_security.c
+++ b/net/ipv6/netfilter/ip6table_security.c
@@ -26,7 +26,7 @@ MODULE_DESCRIPTION("ip6tables security table, for MAC rules");
                                 (1 << NF_INET_FORWARD) | \
                                 (1 << NF_INET_LOCAL_OUT)
 
-static struct
+static const struct
 {
         struct ip6t_replace repl;
         struct ip6t_standard entries[3];
@@ -56,7 +56,7 @@ static struct
         .term = IP6T_ERROR_INIT,                /* ERROR */
 };
 
-static struct xt_table security_table = {
+static const struct xt_table security_table = {
         .name           = "security",
         .valid_hooks    = SECURITY_VALID_HOOKS,
         .me             = THIS_MODULE,
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 025d1a0af78b..a6ac83a93348 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -736,16 +736,17 @@ xt_replace_table(struct xt_table *table,
 }
 EXPORT_SYMBOL_GPL(xt_replace_table);
 
-struct xt_table *xt_register_table(struct net *net, struct xt_table *table,
+struct xt_table *xt_register_table(struct net *net,
+                                   const struct xt_table *input_table,
                                    struct xt_table_info *bootstrap,
                                    struct xt_table_info *newinfo)
 {
         int ret;
         struct xt_table_info *private;
-        struct xt_table *t;
+        struct xt_table *t, *table;
 
         /* Don't add one object to multiple lists. */
-        table = kmemdup(table, sizeof(struct xt_table), GFP_KERNEL);
+        table = kmemdup(input_table, sizeof(struct xt_table), GFP_KERNEL);
         if (!table) {
                 ret = -ENOMEM;
                 goto out;