From 51263fffadee28c99152fb78a2d41e3d10c9b0b5 Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Mon, 2 Jun 2014 13:21:57 +0200 Subject: [PATCH] 6lowpan_rtnl: fix fragmentation with two fragments This patch fix the 6LoWPAN fragmentation for the case if we have exactly two fragments. The problem is that the (skb_unprocessed >= frag_cap) condition is always false on the second fragment after sending the first fragment. A fragmentation with only one fragment doesn't make any sense. The solution is that we use a do while loop here, that ensures we sending always a minimum of two fragments if we need a fragmentation. This issue was introduced by commit d4b2816d67d6e07b2f27037f282d8db03a5829d7 ("6lowpan: fix fragmentation"). Signed-off-by: Alexander Aring Signed-off-by: David S. Miller --- net/ieee802154/6lowpan_rtnl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ieee802154/6lowpan_rtnl.c b/net/ieee802154/6lowpan_rtnl.c index 1ae8a5628fb5..9d57026fd9d5 100644 --- a/net/ieee802154/6lowpan_rtnl.c +++ b/net/ieee802154/6lowpan_rtnl.c @@ -312,7 +312,7 @@ lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *dev, frag_hdr[0] |= LOWPAN_DISPATCH_FRAGN; frag_cap = round_down(payload_cap - LOWPAN_FRAGN_HEAD_SIZE, 8); - while (skb_unprocessed >= frag_cap) { + do { dgram_offset += frag_len; skb_offset += frag_len; skb_unprocessed -= frag_len; @@ -328,7 +328,7 @@ lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *dev, __func__, frag_tag, skb_offset); goto err; } - } + } while (skb_unprocessed >= frag_cap); consume_skb(skb); return NET_XMIT_SUCCESS; -- 2.39.5