[TCP]: Fix size calculation in sk_stream_alloc_pskb

[~andy/linux] / include / net / sock.h

diff --git a/include/net/sock.h b/include/net/sock.h
index 5504fb9fa88a43e9cbce0cf7e4a9db54b188ec3b..567e468d74929c993f6c8fd14271068dc6bc0eb3 100644 (file)
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1235,14 +1235,16 @@ static inline struct sk_buff *sk_stream_alloc_pskb(struct sock *sk,
                                                   gfp_t gfp)
 {
        struct sk_buff *skb;
-       int hdr_len;
 
-       hdr_len = SKB_DATA_ALIGN(sk->sk_prot->max_header);
-       skb = alloc_skb_fclone(size + hdr_len, gfp);
+       skb = alloc_skb_fclone(size + sk->sk_prot->max_header, gfp);
        if (skb) {
                skb->truesize += mem;
                if (sk_stream_wmem_schedule(sk, skb->truesize)) {
-                       skb_reserve(skb, hdr_len);
+                       /*
+                        * Make sure that we have exactly size bytes
+                        * available to the caller, no more, no less.
+                        */
+                       skb_reserve(skb, skb_tailroom(skb) - size);
                        return skb;
                }
                __kfree_skb(skb);