networking: introduce and use skb_put_data()

A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.

An spatch similar to the one for skb_put_zero() converts many
of the places using it:

    @@
    identifier p, p2;
    expression len, skb, data;
    type t, t2;
    @@
    (
    -p = skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    |
    -p = (t)skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, len);
    |
    -memcpy(p, data, len);
    )

    @@
    type t, t2;
    identifier p, p2;
    expression skb, data;
    @@
    t *p;
    ...
    (
    -p = skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    |
    -p = (t *)skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, sizeof(*p));
    |
    -memcpy(p, data, sizeof(*p));
    )

    @@
    expression skb, len, data;
    @@
    -memcpy(skb_put(skb, len), data, len);
    +skb_put_data(skb, data, len);

(again, manually post-processed to retain some comments)

Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 11 insertions, 21 deletions

diff --git a/drivers/staging/rtl8192e/rtllib_rx.c b/drivers/staging/rtl8192e/rtllib_rx.c
index 43a77745e6fb..bae98ca0a9b6 100644
--- a/drivers/staging/rtl8192e/rtllib_rx.c
+++ b/drivers/staging/rtl8192e/rtllib_rx.c
@@ -817,8 +817,7 @@ static u8 parse_subframe(struct rtllib_device *ieee, struct sk_buff *skb,
 		if (!sub_skb)
 			return 0;
 		skb_reserve(sub_skb, 12);
-		data_ptr = (u8 *)skb_put(sub_skb, skb->len);
-		memcpy(data_ptr, skb->data, skb->len);
+		data_ptr = skb_put_data(sub_skb, skb->data, skb->len);
 		sub_skb->dev = ieee->dev;
 
 		rxb->subframes[0] = sub_skb;
@@ -870,8 +869,7 @@ static u8 parse_subframe(struct rtllib_device *ieee, struct sk_buff *skb,
 		if (!sub_skb)
 			return 0;
 		skb_reserve(sub_skb, 12);
-		data_ptr = (u8 *)skb_put(sub_skb, nSubframe_Length);
-		memcpy(data_ptr, skb->data, nSubframe_Length);
+		data_ptr = skb_put_data(sub_skb, skb->data, nSubframe_Length);
 
 		sub_skb->dev = ieee->dev;
 		rxb->subframes[rxb->nr_subframes++] = sub_skb;
@@ -1141,13 +1139,12 @@ static int rtllib_rx_decrypt(struct rtllib_device *ieee, struct sk_buff *skb,
 			/* copy first fragment (including full headers) into
 			 * beginning of the fragment cache skb
 			 */
-			memcpy(skb_put(frag_skb, flen), skb->data, flen);
+			skb_put_data(frag_skb, skb->data, flen);
 		} else {
 			/* append frame payload to the end of the fragment
 			 * cache skb
 			 */
-			memcpy(skb_put(frag_skb, flen), skb->data + hdrlen,
-			       flen);
+			skb_put_data(frag_skb, skb->data + hdrlen, flen);
 		}
 		dev_kfree_skb_any(skb);
 		skb = NULL;
diff --git a/drivers/staging/rtl8192e/rtllib_softmac.c b/drivers/staging/rtl8192e/rtllib_softmac.c
index eeda17d6409b..60d07d0bb4eb 100644
--- a/drivers/staging/rtl8192e/rtllib_softmac.c
+++ b/drivers/staging/rtl8192e/rtllib_softmac.c
@@ -1272,8 +1272,7 @@ rtllib_association_req(struct rtllib_network *beacon,
 	hdr->info_element[0].id = MFIE_TYPE_SSID;
 
 	hdr->info_element[0].len = beacon->ssid_len;
-	tag = skb_put(skb, beacon->ssid_len);
-	memcpy(tag, beacon->ssid, beacon->ssid_len);
+	tag = skb_put_data(skb, beacon->ssid, beacon->ssid_len);
 
 	tag = skb_put(skb, rate_len);
 
@@ -1349,8 +1348,7 @@ rtllib_association_req(struct rtllib_network *beacon,
 	}
 
 	if (wpa_ie_len) {
-		tag = skb_put(skb, ieee->wpa_ie_len);
-		memcpy(tag, ieee->wpa_ie, ieee->wpa_ie_len);
+		tag = skb_put_data(skb, ieee->wpa_ie, ieee->wpa_ie_len);
 
 		if (PMKCacheIdx >= 0) {
 			tag = skb_put(skb, 18);
@@ -1366,8 +1364,7 @@ rtllib_association_req(struct rtllib_network *beacon,
 	}
 
 	if (wps_ie_len && ieee->wps_ie) {
-		tag = skb_put(skb, wps_ie_len);
-		memcpy(tag, ieee->wps_ie, wps_ie_len);
+		tag = skb_put_data(skb, ieee->wps_ie, wps_ie_len);
 	}
 
 	tag = skb_put(skb, turbo_info_len);
diff --git a/drivers/staging/rtl8192e/rtllib_tx.c b/drivers/staging/rtl8192e/rtllib_tx.c
index 78a3ad5b231f..fc88d47dea43 100644
--- a/drivers/staging/rtl8192e/rtllib_tx.c
+++ b/drivers/staging/rtl8192e/rtllib_tx.c
@@ -624,8 +624,7 @@ static int rtllib_xmit_inter(struct sk_buff *skb, struct net_device *dev)
 
 			txb->encrypted = 0;
 			txb->payload_size = cpu_to_le16(skb->len);
-			memcpy(skb_put(txb->fragments[0], skb->len), skb->data,
-			       skb->len);
+			skb_put_data(txb->fragments[0], skb->data, skb->len);
 
 			goto success;
 		}
@@ -818,9 +817,7 @@ static int rtllib_xmit_inter(struct sk_buff *skb, struct net_device *dev)
 			} else {
 				tcb_desc->bHwSec = 0;
 			}
-			frag_hdr = (struct rtllib_hdr_3addrqos *)
-				   skb_put(skb_frag, hdr_len);
-			memcpy(frag_hdr, &header, hdr_len);
+			frag_hdr = skb_put_data(skb_frag, &header, hdr_len);
 
 			/* If this is not the last fragment, then add the
 			 * MOREFRAGS bit to the frame control
@@ -852,7 +849,7 @@ static int rtllib_xmit_inter(struct sk_buff *skb, struct net_device *dev)
 				bytes -= SNAP_SIZE + sizeof(u16);
 			}
 
-			memcpy(skb_put(skb_frag, bytes), skb->data, bytes);
+			skb_put_data(skb_frag, skb->data, bytes);
 
 			/* Advance the SKB... */
 			skb_pull(skb, bytes);
@@ -895,8 +892,7 @@ static int rtllib_xmit_inter(struct sk_buff *skb, struct net_device *dev)
 
 		txb->encrypted = 0;
 		txb->payload_size = cpu_to_le16(skb->len);
-		memcpy(skb_put(txb->fragments[0], skb->len), skb->data,
-		       skb->len);
+		skb_put_data(txb->fragments[0], skb->data, skb->len);
 	}
 
  success: