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, 11 insertions, 21 deletions

diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c
index c379c99cd1d8..86740670102d 100644
--- a/net/mac80211/tdls.c
+++ b/net/mac80211/tdls.c
@@ -388,8 +388,7 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 					     before_ext_cap,
 					     ARRAY_SIZE(before_ext_cap),
 					     offset);
-		pos = skb_put(skb, noffset - offset);
-		memcpy(pos, extra_ies + offset, noffset - offset);
+		pos = skb_put_data(skb, extra_ies + offset, noffset - offset);
 		offset = noffset;
 	}
 
@@ -418,8 +417,7 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 					     before_ht_cap,
 					     ARRAY_SIZE(before_ht_cap),
 					     offset);
-		pos = skb_put(skb, noffset - offset);
-		memcpy(pos, extra_ies + offset, noffset - offset);
+		pos = skb_put_data(skb, extra_ies + offset, noffset - offset);
 		offset = noffset;
 	}
 
@@ -490,8 +488,7 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 					     before_vht_cap,
 					     ARRAY_SIZE(before_vht_cap),
 					     offset);
-		pos = skb_put(skb, noffset - offset);
-		memcpy(pos, extra_ies + offset, noffset - offset);
+		pos = skb_put_data(skb, extra_ies + offset, noffset - offset);
 		offset = noffset;
 	}
 
@@ -532,8 +529,7 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 	/* add any remaining IEs */
 	if (extra_ies_len) {
 		noffset = extra_ies_len;
-		pos = skb_put(skb, noffset - offset);
-		memcpy(pos, extra_ies + offset, noffset - offset);
+		pos = skb_put_data(skb, extra_ies + offset, noffset - offset);
 	}
 
 }
@@ -575,8 +571,7 @@ ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
 					     before_qos,
 					     ARRAY_SIZE(before_qos),
 					     offset);
-		pos = skb_put(skb, noffset - offset);
-		memcpy(pos, extra_ies + offset, noffset - offset);
+		pos = skb_put_data(skb, extra_ies + offset, noffset - offset);
 		offset = noffset;
 	}
 
@@ -596,8 +591,7 @@ ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
 					     before_ht_op,
 					     ARRAY_SIZE(before_ht_op),
 					     offset);
-		pos = skb_put(skb, noffset - offset);
-		memcpy(pos, extra_ies + offset, noffset - offset);
+		pos = skb_put_data(skb, extra_ies + offset, noffset - offset);
 		offset = noffset;
 	}
 
@@ -638,8 +632,7 @@ ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
 	/* add any remaining IEs */
 	if (extra_ies_len) {
 		noffset = extra_ies_len;
-		pos = skb_put(skb, noffset - offset);
-		memcpy(pos, extra_ies + offset, noffset - offset);
+		pos = skb_put_data(skb, extra_ies + offset, noffset - offset);
 	}
 }
 
@@ -670,8 +663,7 @@ ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
 					     before_lnkie,
 					     ARRAY_SIZE(before_lnkie),
 					     offset);
-		pos = skb_put(skb, noffset - offset);
-		memcpy(pos, extra_ies + offset, noffset - offset);
+		pos = skb_put_data(skb, extra_ies + offset, noffset - offset);
 		offset = noffset;
 	}
 
@@ -680,8 +672,7 @@ ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
 	/* add any remaining IEs */
 	if (extra_ies_len) {
 		noffset = extra_ies_len;
-		pos = skb_put(skb, noffset - offset);
-		memcpy(pos, extra_ies + offset, noffset - offset);
+		pos = skb_put_data(skb, extra_ies + offset, noffset - offset);
 	}
 }
 
@@ -696,7 +687,7 @@ ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
 		ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 
 	if (extra_ies_len)
-		memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
+		skb_put_data(skb, extra_ies, extra_ies_len);
 }
 
 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
@@ -726,8 +717,7 @@ static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
 	case WLAN_TDLS_TEARDOWN:
 	case WLAN_TDLS_DISCOVERY_REQUEST:
 		if (extra_ies_len)
-			memcpy(skb_put(skb, extra_ies_len), extra_ies,
-			       extra_ies_len);
+			skb_put_data(skb, extra_ies, extra_ies_len);
 		if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
 			ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 		break;