From aea0bb4f8ee513537ad84b9f3f609f96e272d98e Mon Sep 17 00:00:00 2001 From: Thomas Graf Date: Tue, 14 Jan 2014 16:27:49 +0000 Subject: [PATCH] openvswitch: Pad OVS_PACKET_ATTR_PACKET if linear copy was performed While the zerocopy method is correctly omitted if user space does not support unaligned Netlink messages. The attribute is still not padded correctly as skb_zerocopy() will not ensure padding and the attribute size is no longer pre calculated though nla_reserve() which ensured padding previously. This patch applies appropriate padding if a linear data copy was performed in skb_zerocopy(). Signed-off-by: Thomas Graf Acked-by: Zoltan Kiss Signed-off-by: Jesse Gross --- net/openvswitch/datapath.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index df4692826ead..d1a73a6102f8 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -466,6 +466,14 @@ static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb, skb_zerocopy(user_skb, skb, skb->len, hlen); + /* Pad OVS_PACKET_ATTR_PACKET if linear copy was performed */ + if (!(dp->user_features & OVS_DP_F_UNALIGNED)) { + size_t plen = NLA_ALIGN(user_skb->len) - user_skb->len; + + if (plen > 0) + memset(skb_put(user_skb, plen), 0, plen); + } + ((struct nlmsghdr *) user_skb->data)->nlmsg_len = user_skb->len; err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);