2 files changed, 14 insertions, 17 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 830f58fa03a2..93e4db221585 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -975,15 +975,16 @@ static inline void skb_reserve(struct sk_buff *skb, int len)
 #define NET_SKB_PAD     16
 #endif
 
-extern int ___pskb_trim(struct sk_buff *skb, unsigned int len, int realloc);
+extern int ___pskb_trim(struct sk_buff *skb, unsigned int len);
 
 static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
 {
-        if (!skb->data_len) {
-                skb->len  = len;
-                skb->tail = skb->data + len;
-        } else
-                ___pskb_trim(skb, len, 0);
+        if (unlikely(skb->data_len)) {
+                WARN_ON(1);
+                return;
+        }
+        skb->len  = len;
+        skb->tail = skb->data + len;
 }
 
 /**
@@ -993,6 +994,7 @@ static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
  *
  *      Cut the length of a buffer down by removing data from the tail. If
  *      the buffer is already under the length specified it is not modified.
+ *      The skb must be linear.
  */
 static inline void skb_trim(struct sk_buff *skb, unsigned int len)
 {
@@ -1003,12 +1005,10 @@ static inline void skb_trim(struct sk_buff *skb, unsigned int len)
 
 static inline int __pskb_trim(struct sk_buff *skb, unsigned int len)
 {
-        if (!skb->data_len) {
-                skb->len  = len;
-                skb->tail = skb->data+len;
-                return 0;
-        }
-        return ___pskb_trim(skb, len, 1);
+        if (skb->data_len)
+                return ___pskb_trim(skb, len);
+        __skb_trim(skb, len);
+        return 0;
 }
 
 static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 96cdcbe24ba2..bb7210f4005e 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -801,12 +801,10 @@ struct sk_buff *skb_pad(struct sk_buff *skb, int pad)
         return nskb;
 }       
  
-/* Trims skb to length len. It can change skb pointers, if "realloc" is 1.
- * If realloc==0 and trimming is impossible without change of data,
- * it is BUG().
+/* Trims skb to length len. It can change skb pointers.
  */
 
-int ___pskb_trim(struct sk_buff *skb, unsigned int len, int realloc)
+int ___pskb_trim(struct sk_buff *skb, unsigned int len)
 {
         int offset = skb_headlen(skb);
         int nfrags = skb_shinfo(skb)->nr_frags;
@@ -816,7 +814,6 @@ int ___pskb_trim(struct sk_buff *skb, unsigned int len, int realloc)
                 int end = offset + skb_shinfo(skb)->frags[i].size;
                 if (end > len) {
                         if (skb_cloned(skb)) {
-                                BUG_ON(!realloc);
                                 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
                                         return -ENOMEM;
                         }