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>

1 files changed, 2 insertions, 3 deletions

diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
index c854a557998b..1d6e180052b8 100644
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -2020,8 +2020,7 @@ static void hw_scan_work(struct work_struct *work)
 			memcpy(mgmt->bssid, req->bssid, ETH_ALEN);
 
 			if (req->ie_len)
-				memcpy(skb_put(probe, req->ie_len), req->ie,
-				       req->ie_len);
+				skb_put_data(probe, req->ie, req->ie_len);
 
 			local_bh_disable();
 			mac80211_hwsim_tx_frame(hwsim->hw, probe,
@@ -3021,7 +3020,7 @@ static int hwsim_cloned_frame_received_nl(struct sk_buff *skb_2,
 		goto err;
 
 	/* Copy the data */
-	memcpy(skb_put(skb, frame_data_len), frame_data, frame_data_len);
+	skb_put_data(skb, frame_data, frame_data_len);
 
 	data2 = get_hwsim_data_ref_from_addr(dst);
 	if (!data2)