diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 27c990bf2320..97a02d3f7d87 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -878,7 +878,7 @@ static int ieee80211_fragment(struct ieee80211_tx_data *tx,
 	}
 
 	/* adjust first fragment's length */
-	skb->len = hdrlen + per_fragm;
+	skb_trim(skb, hdrlen + per_fragm);
 	return 0;
 }