netdev - [PATCH net-next v2 4/4] net: ipv4: convert ip_rcv

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Message-ID: <20250918083127.41147-5-atenart@kernel.org>
Date: Thu, 18 Sep 2025 10:31:17 +0200
From: Antoine Tenart <atenart@...nel.org>
To: davem@...emloft.net,
	kuba@...nel.org,
	pabeni@...hat.com,
	edumazet@...gle.com,
	dsahern@...nel.org
Cc: Antoine Tenart <atenart@...nel.org>,
	netdev@...r.kernel.org
Subject: [PATCH net-next v2 4/4] net: ipv4: convert ip_rcv_options to drop reasons

This converts the only path not returning drop reasons in
ip_rcv_finish_core.

Reviewed-by: David Ahern <dsahern@...nel.org>
Signed-off-by: Antoine Tenart <atenart@...nel.org>
---
 net/ipv4/ip_input.c | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 229c7e6b7e4c..f95765f315da 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -263,10 +263,11 @@ int ip_local_deliver(struct sk_buff *skb)
 }
 EXPORT_SYMBOL(ip_local_deliver);
 
-static inline bool ip_rcv_options(struct sk_buff *skb, struct net_device *dev)
+static inline enum skb_drop_reason
+ip_rcv_options(struct sk_buff *skb, struct net_device *dev)
 {
-	struct ip_options *opt;
 	const struct iphdr *iph;
+	struct ip_options *opt;
 
 	/* It looks as overkill, because not all
 	   IP options require packet mangling.
@@ -277,7 +278,7 @@ static inline bool ip_rcv_options(struct sk_buff *skb, struct net_device *dev)
 	*/
 	if (skb_cow(skb, skb_headroom(skb))) {
 		__IP_INC_STATS(dev_net(dev), IPSTATS_MIB_INDISCARDS);
-		goto drop;
+		return SKB_DROP_REASON_NOMEM;
 	}
 
 	iph = ip_hdr(skb);
@@ -286,7 +287,7 @@ static inline bool ip_rcv_options(struct sk_buff *skb, struct net_device *dev)
 
 	if (ip_options_compile(dev_net(dev), opt, skb)) {
 		__IP_INC_STATS(dev_net(dev), IPSTATS_MIB_INHDRERRORS);
-		goto drop;
+		return SKB_DROP_REASON_IP_INHDR;
 	}
 
 	if (unlikely(opt->srr)) {
@@ -298,17 +299,15 @@ static inline bool ip_rcv_options(struct sk_buff *skb, struct net_device *dev)
 					net_info_ratelimited("source route option %pI4 -> %pI4\n",
 							     &iph->saddr,
 							     &iph->daddr);
-				goto drop;
+				return SKB_DROP_REASON_NOT_SPECIFIED;
 			}
 		}
 
 		if (ip_options_rcv_srr(skb, dev))
-			goto drop;
+			return SKB_DROP_REASON_NOT_SPECIFIED;
 	}
 
-	return false;
-drop:
-	return true;
+	return SKB_NOT_DROPPED_YET;
 }
 
 static bool ip_can_use_hint(const struct sk_buff *skb, const struct iphdr *iph,
@@ -388,9 +387,10 @@ static int ip_rcv_finish_core(struct net *net,
 	}
 #endif
 
-	if (iph->ihl > 5 && ip_rcv_options(skb, dev)) {
-		drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
-		goto drop;
+	if (iph->ihl > 5) {
+		drop_reason = ip_rcv_options(skb, dev);
+		if (drop_reason != SKB_NOT_DROPPED_YET)
+			goto drop;
 	}
 
 	rt = skb_rtable(skb);
-- 
2.51.0