[PATCH 5.16 0969/1017] net: add skb_set_end_offset() helper

Greg Kroah-Hartman
2022-04-05T10:28:40Z

From: Eric Dumazet <edumazet@google.com>

commit 763087dab97547230a6807c865a6a5ae53a59247 upstream.

We have multiple places where this helper is convenient,
and plan using it in the following patch.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/linux/skbuff.h | 10 ++++++++++
net/core/skbuff.c | 19 +++++--------------
2 files changed, 15 insertions(+), 14 deletions(-)

--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1446,6 +1446,11 @@ static inline unsigned int skb_end_offse
{
return skb->end;
}
+
+static inline void skb_set_end_offset(struct sk_buff *skb, unsigned int offset)
+{
+ skb->end = offset;
+}
#else
static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
{
@@ -1456,6 +1461,11 @@ static inline unsigned int skb_end_offse
{
return skb->end - skb->head;
}
+
+static inline void skb_set_end_offset(struct sk_buff *skb, unsigned int offset)
+{
+ skb->end = skb->head + offset;
+}
#endif

/* Internal */
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -201,7 +201,7 @@ static void __build_skb_around(struct sk
skb->head = data;
skb->data = data;
skb_reset_tail_pointer(skb);
- skb->end = skb->tail + size;
+ skb_set_end_offset(skb, size);
skb->mac_header = (typeof(skb->mac_header))~0U;
skb->transport_header = (typeof(skb->transport_header))~0U;

@@ -1738,11 +1738,10 @@ int pskb_expand_head(struct sk_buff *skb
skb->head = data;
skb->head_frag = 0;
skb->data += off;
+
+ skb_set_end_offset(skb, size);
#ifdef NET_SKBUFF_DATA_USES_OFFSET
- skb->end = size;
off = nhead;
-#else
- skb->end = skb->head + size;
#endif
skb->tail += off;
skb_headers_offset_update(skb, nhead);
@@ -6138,11 +6137,7 @@ static int pskb_carve_inside_header(stru
skb->head = data;
skb->data = data;
skb->head_frag = 0;
-#ifdef NET_SKBUFF_DATA_USES_OFFSET
- skb->end = size;
-#else
- skb->end = skb->head + size;
-#endif
+ skb_set_end_offset(skb, size);
skb_set_tail_pointer(skb, skb_headlen(skb));
skb_headers_offset_update(skb, 0);
skb->cloned = 0;
@@ -6280,11 +6275,7 @@ static int pskb_carve_inside_nonlinear(s
skb->head = data;
skb->head_frag = 0;
skb->data = data;
-#ifdef NET_SKBUFF_DATA_USES_OFFSET
- skb->end = size;
-#else
- skb->end = skb->head + size;
-#endif
+ skb_set_end_offset(skb, size);
skb_reset_tail_pointer(skb);
skb_headers_offset_update(skb, 0);
skb->cloned = 0;