Commit ac74f87c authored Jul 14, 2018 by Alexander Aring Committed by Stefan Schmidt Aug 06, 2018

net: 6lowpan: fix reserved space for single frames

This patch fixes patch add handling to take care tail and headroom for
single 6lowpan frames. We need to be sure we have a skb with the right
head and tailroom for single frames. This patch do it by using
skb_copy_expand() if head and tailroom is not enough allocated by upper
layer.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195059


Reported-by: David Palma <david.palma@ntnu.no>
Reported-by: Rabi Narayan Sahoo <rabinarayans0828@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>

parent a3046108

net/ieee802154/6lowpan/tx.c

+18 −3

Original line number	Diff line number	Diff line
		@@ -265,9 +265,24 @@ netdev_tx_t lowpan_xmit(struct sk_buff skb, struct net_device ldev)
		/* We must take a copy of the skb before we modify/replace the ipv6
		* header as the header could be used elsewhere
		*/
		if (unlikely(skb_headroom(skb) < ldev->needed_headroom \|\|
		skb_tailroom(skb) < ldev->needed_tailroom)) {
		struct sk_buff *nskb;

		nskb = skb_copy_expand(skb, ldev->needed_headroom,
		ldev->needed_tailroom, GFP_ATOMIC);
		if (likely(nskb)) {
		consume_skb(skb);
		skb = nskb;
		} else {
		kfree_skb(skb);
		return NET_XMIT_DROP;
		}
		} else {
		skb = skb_unshare(skb, GFP_ATOMIC);
		if (!skb)
		return NET_XMIT_DROP;
		}

		ret = lowpan_header(skb, ldev, &dgram_size, &dgram_offset);
		if (ret < 0) {