IPv6 routing, NLM_F_* flag support: warn if new route is created without NLM_F_CREATE

The support for NLM_F_* flags at IPv6 routing requests.

Warn if NLM_F_CREATE flag is not defined for RTM_NEWROUTE request,
creating new table. Later NLM_F_CREATE may be required for
new route creation.

Patch created against linux-3.2-rc1

Signed-off-by: Matti Vaittinen <Mazziesaccount@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 2 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 8473016bba4a..05c89be04c9f 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1230,9 +1230,18 @@ int ip6_route_add(struct fib6_config *cfg)
         if (cfg->fc_metric == 0)
                 cfg->fc_metric = IP6_RT_PRIO_USER;
 
-        table = fib6_new_table(net, cfg->fc_table);
+        err = -ENOBUFS;
+        if (NULL != cfg->fc_nlinfo.nlh &&
+            !(cfg->fc_nlinfo.nlh->nlmsg_flags&NLM_F_CREATE)) {
+                table = fib6_get_table(net, cfg->fc_table);
+                if (table == NULL) {
+                        printk(KERN_WARNING "IPv6: NLM_F_CREATE should be specified when creating new route\n");
+                        table = fib6_new_table(net, cfg->fc_table);
+                }
+        } else {
+                table = fib6_new_table(net, cfg->fc_table);
+        }
         if (table == NULL) {
-                err = -ENOBUFS;
                 goto out;
         }