Re: [PATCH net-next v4 04/10] ip_tunnel: add __iptunnel_pull_header_reason()

[Ido Schimmel <idosch@nvidia.com>]

On Wed, Sep 23, 2026 at 01:15:01AM +0300, Anton Danilov wrote:
> diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
> index 7102aa11fae2..c68031d01c39 100644
> --- a/include/net/ip_tunnels.h
> +++ b/include/net/ip_tunnels.h
> @@ -614,8 +614,17 @@ static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
>  	return INET_ECN_encapsulate(tos, inner);
>  }
>  
> -int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
> -			   __be16 inner_proto, bool raw_proto, bool xnet);
> +enum skb_drop_reason
> +__iptunnel_pull_header_reason(struct sk_buff *skb, int hdr_len,
> +			      __be16 inner_proto, bool raw_proto, bool xnet);
> +
> +static inline int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
> +					 __be16 inner_proto, bool raw_proto,
> +					 bool xnet)
> +{
> +	return __iptunnel_pull_header_reason(skb, hdr_len, inner_proto,
> +					     raw_proto, xnet) ? -ENOMEM : 0;
> +}

Either append patches to this series or as a follow-up, after this
series the only caller of __iptunnel_pull_header() other than
iptunnel_pull_header() is the VXLAN driver and it should be converted to
report the actual drop reason instead of NOMEM:

diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
index 347245cc1de4..5c429a70987e 100644
--- a/drivers/net/vxlan/vxlan_core.c
+++ b/drivers/net/vxlan/vxlan_core.c
@@ -1720,11 +1720,11 @@ static int vxlan_rcv(struct sock *sk, struct sk_buff *skb)
 		raw_proto = true;
 	}
 
-	if (__iptunnel_pull_header(skb, VXLAN_HLEN, protocol, raw_proto,
-				   !net_eq(vxlan->net, dev_net(vxlan->dev)))) {
-		reason = SKB_DROP_REASON_NOMEM;
+	reason = __iptunnel_pull_header_reason(skb, VXLAN_HLEN, protocol,
+					       raw_proto,
+					       !net_eq(vxlan->net, dev_net(vxlan->dev)));
+	if (reason)
 		goto drop;
-	}
 
 	if (vxlan->cfg.flags & VXLAN_F_REMCSUM_RX) {
 		reason = vxlan_remcsum(skb, vxlan->cfg.flags);

Then remove __iptunnel_pull_header():

diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
index 27a9e097996b..a94dadfa81f2 100644
--- a/include/net/ip_tunnels.h
+++ b/include/net/ip_tunnels.h
@@ -614,18 +614,11 @@ enum skb_drop_reason
 __iptunnel_pull_header_reason(struct sk_buff *skb, int hdr_len,
 			      __be16 inner_proto, bool raw_proto, bool xnet);
 
-static inline int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
-					 __be16 inner_proto, bool raw_proto,
-					 bool xnet)
+static inline bool iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
+					__be16 inner_proto, bool xnet)
 {
-	return __iptunnel_pull_header_reason(skb, hdr_len, inner_proto,
-					     raw_proto, xnet) ? -ENOMEM : 0;
-}
-
-static inline int iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
-				       __be16 inner_proto, bool xnet)
-{
-	return __iptunnel_pull_header(skb, hdr_len, inner_proto, false, xnet);
+	return __iptunnel_pull_header_reason(skb, hdr_len, inner_proto, false,
+					     xnet) != SKB_NOT_DROPPED_YET;
 }
 
 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,