[NETFILTER]: nfnetlink_queue: fix computation of allocated size for netlink skb.

Size of the netlink skb was wrongly computed because the formula was using
NLMSG_ALIGN instead of NLMSG_SPACE. NLMSG_ALIGN does not add the room for
netlink header as NLMSG_SPACE does. This was causing a failure of message
building in some cases.

On my test system, all messages for packets in range [8*k+41, 8*k+48] where k
is an integer were invalid and the corresponding packets were dropped.

Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 0043d3a9f87eb5bbb477c96f64d99a60d6320e6a..c0cc3d3618a3d8abd878a0cb539e1eae2332e454 100644 (file)
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -224,7 +224,7 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
        struct net_device *indev;
        struct net_device *outdev;
 
-       size =    NLMSG_ALIGN(sizeof(struct nfgenmsg))
+       size =    NLMSG_SPACE(sizeof(struct nfgenmsg))
                + nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
                + nla_total_size(sizeof(u_int32_t))     /* ifindex */
                + nla_total_size(sizeof(u_int32_t))     /* ifindex */