diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index 8edfea5da5729b7e02dacfe820f9c0eb97d4c5ee..872c8f97a30c8e0e5831aeaf139a5a490c4b4451 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -422,44 +422,60 @@ lowpan_fragment_xmit(struct sk_buff *skb, u8 *head,
 static int
 lowpan_skb_fragmentation(struct sk_buff *skb, struct net_device *dev)
 {
-	int  err, header_length, payload_length, tag, offset = 0;
+	int err;
+	u16 dgram_offset, dgram_size, payload_length, header_length,
+	    lowpan_size, frag_plen, offset, tag;
 	u8 head[5];
 
 	header_length = skb->mac_len;
 	payload_length = skb->len - header_length;
 	tag = lowpan_dev_info(dev)->fragment_tag++;
+	lowpan_size = skb_network_header_len(skb);
+	dgram_size = lowpan_uncompress_size(skb, &dgram_offset) -
+		     header_length;
 
 	/* first fragment header */
-	head[0] = LOWPAN_DISPATCH_FRAG1 | ((payload_length >> 8) & 0x7);
-	head[1] = payload_length & 0xff;
+	head[0] = LOWPAN_DISPATCH_FRAG1 | ((dgram_size >> 8) & 0x7);
+	head[1] = dgram_size & 0xff;
 	head[2] = tag >> 8;
 	head[3] = tag & 0xff;
 
-	err = lowpan_fragment_xmit(skb, head, header_length, LOWPAN_FRAG_SIZE,
-				   0, LOWPAN_DISPATCH_FRAG1);
+	/* calc the nearest payload length(divided to 8) for first fragment
+	 * which fits into a IEEE802154_MTU
+	 */
+	frag_plen = round_down(IEEE802154_MTU - header_length -
+			       LOWPAN_FRAG1_HEAD_SIZE - lowpan_size -
+			       IEEE802154_MFR_SIZE, 8);
 
+	err = lowpan_fragment_xmit(skb, head, header_length,
+				   frag_plen + lowpan_size, 0,
+				   LOWPAN_DISPATCH_FRAG1);
 	if (err) {
 		pr_debug("%s unable to send FRAG1 packet (tag: %d)",
 			 __func__, tag);
 		goto exit;
 	}
 
-	offset = LOWPAN_FRAG_SIZE;
+	offset = lowpan_size + frag_plen;
+	dgram_offset += frag_plen;
 
 	/* next fragment header */
 	head[0] &= ~LOWPAN_DISPATCH_FRAG1;
 	head[0] |= LOWPAN_DISPATCH_FRAGN;
 
+	frag_plen = round_down(IEEE802154_MTU - header_length -
+			       LOWPAN_FRAGN_HEAD_SIZE - IEEE802154_MFR_SIZE, 8);
+
 	while (payload_length - offset > 0) {
-		int len = LOWPAN_FRAG_SIZE;
+		int len = frag_plen;
 
-		head[4] = offset / 8;
+		head[4] = dgram_offset >> 3;
 
 		if (payload_length - offset < len)
 			len = payload_length - offset;
 
-		err = lowpan_fragment_xmit(skb, head, header_length,
-					   len, offset, LOWPAN_DISPATCH_FRAGN);
+		err = lowpan_fragment_xmit(skb, head, header_length, len,
+					   offset, LOWPAN_DISPATCH_FRAGN);
 		if (err) {
 			pr_debug("%s unable to send a subsequent FRAGN packet "
 				 "(tag: %d, offset: %d", __func__, tag, offset);
@@ -467,6 +483,7 @@ lowpan_skb_fragmentation(struct sk_buff *skb, struct net_device *dev)
 		}
 
 		offset += len;
+		dgram_offset += len;
 	}
 
 exit: