net: core: Specify skb_pad()/skb_put_padto() SKB freeing
Rename skb_pad() into __skb_pad() and make it take a third argument:
free_on_error which controls whether kfree_skb() should be called or
not, skb_pad() directly makes use of it and passes true to preserve its
existing behavior. Do exactly the same thing with __skb_put_padto() and
skb_put_padto().
Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Woojung Huh <Woojung.Huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index dbe29b6..d67a818 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -973,7 +973,23 @@ int __must_check skb_to_sgvec_nomark(struct sk_buff *skb, struct scatterlist *sg
int __must_check skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg,
int offset, int len);
int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer);
-int skb_pad(struct sk_buff *skb, int pad);
+int __skb_pad(struct sk_buff *skb, int pad, bool free_on_error);
+
+/**
+ * skb_pad - zero pad the tail of an skb
+ * @skb: buffer to pad
+ * @pad: space to pad
+ *
+ * Ensure that a buffer is followed by a padding area that is zero
+ * filled. Used by network drivers which may DMA or transfer data
+ * beyond the buffer end onto the wire.
+ *
+ * May return error in out of memory cases. The skb is freed on error.
+ */
+static inline int skb_pad(struct sk_buff *skb, int pad)
+{
+ return __skb_pad(skb, pad, true);
+}
#define dev_kfree_skb(a) consume_skb(a)
int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb,
@@ -2825,6 +2841,31 @@ static inline int skb_padto(struct sk_buff *skb, unsigned int len)
* skb_put_padto - increase size and pad an skbuff up to a minimal size
* @skb: buffer to pad
* @len: minimal length
+ * @free_on_error: free buffer on error
+ *
+ * Pads up a buffer to ensure the trailing bytes exist and are
+ * blanked. If the buffer already contains sufficient data it
+ * is untouched. Otherwise it is extended. Returns zero on
+ * success. The skb is freed on error if @free_on_error is true.
+ */
+static inline int __skb_put_padto(struct sk_buff *skb, unsigned int len,
+ bool free_on_error)
+{
+ unsigned int size = skb->len;
+
+ if (unlikely(size < len)) {
+ len -= size;
+ if (__skb_pad(skb, len, free_on_error))
+ return -ENOMEM;
+ __skb_put(skb, len);
+ }
+ return 0;
+}
+
+/**
+ * skb_put_padto - increase size and pad an skbuff up to a minimal size
+ * @skb: buffer to pad
+ * @len: minimal length
*
* Pads up a buffer to ensure the trailing bytes exist and are
* blanked. If the buffer already contains sufficient data it
@@ -2833,15 +2874,7 @@ static inline int skb_padto(struct sk_buff *skb, unsigned int len)
*/
static inline int skb_put_padto(struct sk_buff *skb, unsigned int len)
{
- unsigned int size = skb->len;
-
- if (unlikely(size < len)) {
- len -= size;
- if (skb_pad(skb, len))
- return -ENOMEM;
- __skb_put(skb, len);
- }
- return 0;
+ return __skb_put_padto(skb, len, true);
}
static inline int skb_add_data(struct sk_buff *skb,