[NETNS][ICMP]: Make ctl tables for ICMP sysctls per-net.

Add some flesh to ipv4_sysctl_init_net and ipv4_sysctl_exit_net,
i.e. copy the table, alter .data pointers and register it per-net.

Other ipv4_table's sysctls are now global, but this is going to
change once sysctl permissions patches migrate from -mm tree to 
mainline in 2.6.26 merge window :)

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 91 insertions, 48 deletions

diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h
index e3de0ff8ea4b..af685f71f4b5 100644
--- a/include/net/netns/ipv4.h
+++ b/include/net/netns/ipv4.h
@@ -17,6 +17,7 @@ struct netns_ipv4 {
 #ifdef CONFIG_SYSCTL
         struct ctl_table_header *forw_hdr;
         struct ctl_table_header *frags_hdr;
+        struct ctl_table_header *ipv4_hdr;
 #endif
         struct ipv4_devconf     *devconf_all;
         struct ipv4_devconf     *devconf_dflt;
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index e9585c02f243..c437f804ee38 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -404,38 +404,6 @@ static struct ctl_table ipv4_table[] = {
                 .strategy       = &ipv4_sysctl_local_port_range,
         },
         {
-                .ctl_name       = NET_IPV4_ICMP_ECHO_IGNORE_ALL,
-                .procname       = "icmp_echo_ignore_all",
-                .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
-                .maxlen         = sizeof(int),
-                .mode           = 0644,
-                .proc_handler   = &proc_dointvec
-        },
-        {
-                .ctl_name       = NET_IPV4_ICMP_ECHO_IGNORE_BROADCASTS,
-                .procname       = "icmp_echo_ignore_broadcasts",
-                .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
-                .maxlen         = sizeof(int),
-                .mode           = 0644,
-                .proc_handler   = &proc_dointvec
-        },
-        {
-                .ctl_name       = NET_IPV4_ICMP_IGNORE_BOGUS_ERROR_RESPONSES,
-                .procname       = "icmp_ignore_bogus_error_responses",
-                .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
-                .maxlen         = sizeof(int),
-                .mode           = 0644,
-                .proc_handler   = &proc_dointvec
-        },
-        {
-                .ctl_name       = NET_IPV4_ICMP_ERRORS_USE_INBOUND_IFADDR,
-                .procname       = "icmp_errors_use_inbound_ifaddr",
-                .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
-                .maxlen         = sizeof(int),
-                .mode           = 0644,
-                .proc_handler   = &proc_dointvec
-        },
-        {
                 .ctl_name       = NET_IPV4_ROUTE,
                 .procname       = "route",
                 .maxlen         = 0,
@@ -586,22 +554,6 @@ static struct ctl_table ipv4_table[] = {
                 .proc_handler   = &proc_dointvec
         },
         {
-                .ctl_name       = NET_IPV4_ICMP_RATELIMIT,
-                .procname       = "icmp_ratelimit",
-                .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
-                .maxlen         = sizeof(int),
-                .mode           = 0644,
-                .proc_handler   = &proc_dointvec
-        },
-        {
-                .ctl_name       = NET_IPV4_ICMP_RATEMASK,
-                .procname       = "icmp_ratemask",
-                .data           = &init_net.ipv4.sysctl_icmp_ratemask,
-                .maxlen         = sizeof(int),
-                .mode           = 0644,
-                .proc_handler   = &proc_dointvec
-        },
-        {
                 .ctl_name       = NET_TCP_TW_REUSE,
                 .procname       = "tcp_tw_reuse",
                 .data           = &sysctl_tcp_tw_reuse,
@@ -804,6 +756,58 @@ static struct ctl_table ipv4_table[] = {
         { .ctl_name = 0 }
 };
 
+static struct ctl_table ipv4_net_table[] = {
+        {
+                .ctl_name       = NET_IPV4_ICMP_ECHO_IGNORE_ALL,
+                .procname       = "icmp_echo_ignore_all",
+                .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec
+        },
+        {
+                .ctl_name       = NET_IPV4_ICMP_ECHO_IGNORE_BROADCASTS,
+                .procname       = "icmp_echo_ignore_broadcasts",
+                .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec
+        },
+        {
+                .ctl_name       = NET_IPV4_ICMP_IGNORE_BOGUS_ERROR_RESPONSES,
+                .procname       = "icmp_ignore_bogus_error_responses",
+                .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec
+        },
+        {
+                .ctl_name       = NET_IPV4_ICMP_ERRORS_USE_INBOUND_IFADDR,
+                .procname       = "icmp_errors_use_inbound_ifaddr",
+                .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec
+        },
+        {
+                .ctl_name       = NET_IPV4_ICMP_RATELIMIT,
+                .procname       = "icmp_ratelimit",
+                .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec
+        },
+        {
+                .ctl_name       = NET_IPV4_ICMP_RATEMASK,
+                .procname       = "icmp_ratemask",
+                .data           = &init_net.ipv4.sysctl_icmp_ratemask,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec
+        },
+        { }
+};
+
 struct ctl_path net_ipv4_ctl_path[] = {
         { .procname = "net", .ctl_name = CTL_NET, },
         { .procname = "ipv4", .ctl_name = NET_IPV4, },
@@ -813,11 +817,49 @@ EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
 
 static __net_init int ipv4_sysctl_init_net(struct net *net)
 {
+        struct ctl_table *table;
+
+        table = ipv4_net_table;
+        if (net != &init_net) {
+                table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
+                if (table == NULL)
+                        goto err_alloc;
+
+                table[0].data =
+                        &net->ipv4.sysctl_icmp_echo_ignore_all;
+                table[1].data =
+                        &net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
+                table[2].data =
+                        &net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
+                table[3].data =
+                        &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
+                table[4].data =
+                        &net->ipv4.sysctl_icmp_ratelimit;
+                table[5].data =
+                        &net->ipv4.sysctl_icmp_ratemask;
+        }
+
+        net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
+                        net_ipv4_ctl_path, table);
+        if (net->ipv4.ipv4_hdr == NULL)
+                goto err_reg;
+
         return 0;
+
+err_reg:
+        if (net != &init_net)
+                kfree(table);
+err_alloc:
+        return -ENOMEM;
 }
 
 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
 {
+        struct ctl_table *table;
+
+        table = net->ipv4.ipv4_hdr->ctl_table_arg;
+        unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
+        kfree(table);
 }
 
 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {