[PATCH 4.14 22/29] net: Rename and export copy_skb_header

[Greg Kroah-Hartman]

From: Ilya Lesokhin <ilyal@xxxxxxxxxxxx>

commit 08303c189581c985e60f588ad92a041e46b6e307 upstream.

[ jgross@xxxxxxxx: added as needed by XSA-403 mitigation ]

copy_skb_header is renamed to skb_copy_header and
exported. Exposing this function give more flexibility
in copying SKBs.
skb_copy and skb_copy_expand do not give enough control
over which parts are copied.

Signed-off-by: Ilya Lesokhin <ilyal@xxxxxxxxxxxx>
Signed-off-by: Boris Pismenny <borisp@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 include/linux/skbuff.h |    1 +
 net/core/skbuff.c      |    9 +++++----
 2 files changed, 6 insertions(+), 4 deletions(-)

--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1025,6 +1025,7 @@ static inline struct sk_buff *alloc_skb_
 struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src);
 int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask);
 struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t priority);
+void skb_copy_header(struct sk_buff *new, const struct sk_buff *old);
 struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t priority);
 struct sk_buff *__pskb_copy_fclone(struct sk_buff *skb, int headroom,
 				   gfp_t gfp_mask, bool fclone);
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -1314,7 +1314,7 @@ static void skb_headers_offset_update(st
 	skb->inner_mac_header += off;
 }
 
-static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
+void skb_copy_header(struct sk_buff *new, const struct sk_buff *old)
 {
 	__copy_skb_header(new, old);
 
@@ -1322,6 +1322,7 @@ static void copy_skb_header(struct sk_bu
 	skb_shinfo(new)->gso_segs = skb_shinfo(old)->gso_segs;
 	skb_shinfo(new)->gso_type = skb_shinfo(old)->gso_type;
 }
+EXPORT_SYMBOL(skb_copy_header);
 
 static inline int skb_alloc_rx_flag(const struct sk_buff *skb)
 {
@@ -1365,7 +1366,7 @@ struct sk_buff *skb_copy(const struct sk
 	if (skb_copy_bits(skb, -headerlen, n->head, headerlen + skb->len))
 		BUG();
 
-	copy_skb_header(n, skb);
+	skb_copy_header(n, skb);
 	return n;
 }
 EXPORT_SYMBOL(skb_copy);
@@ -1429,7 +1430,7 @@ struct sk_buff *__pskb_copy_fclone(struc
 		skb_clone_fraglist(n);
 	}
 
-	copy_skb_header(n, skb);
+	skb_copy_header(n, skb);
 out:
 	return n;
 }
@@ -1609,7 +1610,7 @@ struct sk_buff *skb_copy_expand(const st
 			  skb->len + head_copy_len))
 		BUG();
 
-	copy_skb_header(n, skb);
+	skb_copy_header(n, skb);
 
 	skb_headers_offset_update(n, newheadroom - oldheadroom);