ipv6: Do cleanup if attribute validation fails in multipath route

As Nicolas noted, if gateway validation fails walking the multipath
attribute the code should jump to the cleanup to free previously
allocated memory.

Fixes: 7eaa95c8311c ("ipv6: Check attribute length for RTA_GATEWAY when deleting multipath route")
Signed-off-by: David Ahern <dsahern@kernel.org>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://lore.kernel.org/r/20220103170555.94638-1-dsahern@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 087df86c15d18d11a09e6e7d5fd98092aa9513e0..1deb6297aab6691ca1a4d013191927c81116deb9 100644 (file)
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -5277,12 +5277,10 @@ static int ip6_route_multipath_add(struct fib6_config *cfg,
 
                        nla = nla_find(attrs, attrlen, RTA_GATEWAY);
                        if (nla) {
-                               int ret;
-
-                               ret = fib6_gw_from_attr(&r_cfg.fc_gateway, nla,
+                               err = fib6_gw_from_attr(&r_cfg.fc_gateway, nla,
                                                        extack);
-                               if (ret)
-                                       return ret;
+                               if (err)
+                                       goto cleanup;
 
                                r_cfg.fc_flags |= RTF_GATEWAY;
                        }