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.pa...@ntnu.no> Reported-by: Rabi Narayan Sahoo <rabinarayans0...@gmail.com> Signed-off-by: Alexander Aring <ar...@mojatatu.com> --- changes since v2: skb to nskb, pointed out by stefan net/ieee802154/6lowpan/tx.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/net/ieee802154/6lowpan/tx.c b/net/ieee802154/6lowpan/tx.c index e6ff5128e61a..ca53efa17be1 100644 --- a/net/ieee802154/6lowpan/tx.c +++ b/net/ieee802154/6lowpan/tx.c @@ -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 */ - skb = skb_unshare(skb, GFP_ATOMIC); - if (!skb) - return NET_XMIT_DROP; + 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) { -- 2.11.0
