[PATCH v2 net-next 4/7] nexthop: Check NLM_F_REPLACE and NHA_ID in rtm_new_nexthop().

[Kuniyuki Iwashima <kuniyu@amazon.com>]

nexthop_add() checks if NLM_F_REPLACE is specified without
non-zero NHA_ID, which does not require RTNL.

Let's move the check to rtm_new_nexthop().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
---
 net/ipv4/nexthop.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c
index 426cdf301c6f..fb129c830040 100644
--- a/net/ipv4/nexthop.c
+++ b/net/ipv4/nexthop.c
@@ -2928,11 +2928,6 @@ static struct nexthop *nexthop_add(struct net *net, struct nh_config *cfg,
 	struct nexthop *nh;
 	int err;
 
-	if (cfg->nlflags & NLM_F_REPLACE && !cfg->nh_id) {
-		NL_SET_ERR_MSG(extack, "Replace requires nexthop id");
-		return ERR_PTR(-EINVAL);
-	}
-
 	if (!cfg->nh_id) {
 		cfg->nh_id = nh_find_unused_id(net);
 		if (!cfg->nh_id) {
@@ -3247,6 +3242,12 @@ static int rtm_new_nexthop(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (err)
 		goto out;
 
+	if (cfg.nlflags & NLM_F_REPLACE && !cfg.nh_id) {
+		NL_SET_ERR_MSG(extack, "Replace requires nexthop id");
+		err = -EINVAL;
+		goto out;
+	}
+
 	err = rtm_to_nh_config_rtnl(net, tb, &cfg, extack);
 	if (err)
 		goto out;
-- 
2.48.1