From: Justin Iurman <justin.iurman@uliege.be>
Date: Tue, 3 Dec 2024 12:49:42 +0000 (+0100)
Subject: include: net: add static inline dst_dev_overhead() to dst.h
X-Git-Tag: v5.15.179~113
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8513e56e31fcf22dc09ef2b841333a1825a06fa7;p=thirdparty%2Fkernel%2Fstable.git

include: net: add static inline dst_dev_overhead() to dst.h

[ Upstream commit 0600cf40e9b36fe17f9c9f04d4f9cef249eaa5e7 ]

Add static inline dst_dev_overhead() function to include/net/dst.h. This
helper function is used by ioam6_iptunnel, rpl_iptunnel and
seg6_iptunnel to get the dev's overhead based on a cache entry
(dst_entry). If the cache is empty, the default and generic value
skb->mac_len is returned. Otherwise, LL_RESERVED_SPACE() over dst's dev
is returned.

Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Cc: Alexander Lobakin <aleksander.lobakin@intel.com>
Cc: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: c64a0727f9b1 ("net: ipv6: fix dst ref loop on input in seg6 lwt")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/include/net/dst.h b/include/net/dst.h
index 827f99d577331..bf0a9b0cc269c 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -433,6 +433,15 @@ static inline void dst_set_expires(struct dst_entry *dst, int timeout)
 		dst->expires = expires;
 }
 
+static inline unsigned int dst_dev_overhead(struct dst_entry *dst,
+					    struct sk_buff *skb)
+{
+	if (likely(dst))
+		return LL_RESERVED_SPACE(dst->dev);
+
+	return skb->mac_len;
+}
+
 INDIRECT_CALLABLE_DECLARE(int ip6_output(struct net *, struct sock *,
 					 struct sk_buff *));
 INDIRECT_CALLABLE_DECLARE(int ip_output(struct net *, struct sock *,