[NETLINK]: Use nlmsg_trim() where appropriate

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 814bb31..6b7f6dc 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -628,7 +628,7 @@
 
 nlmsg_failure:
 rtattr_failure:
-	skb_trim(skb, b - skb->data);
+	nlmsg_trim(skb, b);
 	return -1;
 }
 
@@ -1182,7 +1182,7 @@
 	return 0;
 
 nlmsg_failure:
-	skb_trim(skb, b - skb->data);
+	nlmsg_trim(skb, b);
 	return -1;
 }
 
@@ -1367,7 +1367,7 @@
 
 rtattr_failure:
 nlmsg_failure:
-	skb_trim(skb, b - skb->data);
+	nlmsg_trim(skb, b);
 	return -1;
 }
 
@@ -1767,7 +1767,7 @@
 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 nlmsg_failure:
-	skb_trim(skb, b - skb->data);
+	nlmsg_trim(skb, b);
 	return -1;
 }
 
@@ -1956,7 +1956,7 @@
 	return skb->len;
 
 nlmsg_failure:
-	skb_trim(skb, b - skb->data);
+	nlmsg_trim(skb, b);
 	return -1;
 }
 
@@ -2157,7 +2157,7 @@
 	return skb->len;
 
 nlmsg_failure:
-	skb_trim(skb, b - skb->data);
+	nlmsg_trim(skb, b);
 	return -1;
 }
 
@@ -2268,7 +2268,7 @@
 	return skb->len;
 
 nlmsg_failure:
-	skb_trim(skb, b - skb->data);
+	nlmsg_trim(skb, b);
 	return -1;
 }
 
@@ -2427,7 +2427,7 @@
 
 nlmsg_failure:
 rtattr_failure:
-	skb_trim(skb, b - skb->data);
+	nlmsg_trim(skb, b);
 	return -1;
 }