From bb9b18fb55b03477fe5bdd3e97245d6d4d3dee4f Mon Sep 17 00:00:00 2001 From: Thomas Graf Date: Sat, 30 Nov 2013 13:21:30 +0100 Subject: genl: Add genlmsg_new_unicast() for unicast message allocation Allocates a new sk_buff large enough to cover the specified payload plus required Netlink headers. Will check receiving socket for memory mapped i/o capability and use it if enabled. Will fall back to non-mapped skb if message size exceeds the frame size of the ring. Signed-of-by: Thomas Graf Reviewed-by: Daniel Borkmann Signed-off-by: Jesse Gross --- net/netlink/genetlink.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'net/netlink') diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 4518a57aa5f..85bf42e2a94 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -453,6 +453,26 @@ int genl_unregister_family(struct genl_family *family) } EXPORT_SYMBOL(genl_unregister_family); +/** + * genlmsg_new_unicast - Allocate generic netlink message for unicast + * @payload: size of the message payload + * @info: information on destination + * @flags: the type of memory to allocate + * + * Allocates a new sk_buff large enough to cover the specified payload + * plus required Netlink headers. Will check receiving socket for + * memory mapped i/o capability and use it if enabled. Will fall back + * to non-mapped skb if message size exceeds the frame size of the ring. + */ +struct sk_buff *genlmsg_new_unicast(size_t payload, struct genl_info *info, + gfp_t flags) +{ + size_t len = nlmsg_total_size(genlmsg_total_size(payload)); + + return netlink_alloc_skb(info->dst_sk, len, info->snd_portid, flags); +} +EXPORT_SYMBOL_GPL(genlmsg_new_unicast); + /** * genlmsg_put - Add generic netlink header to netlink message * @skb: socket buffer holding the message @@ -593,6 +613,7 @@ static int genl_family_rcv_msg(struct genl_family *family, info.genlhdr = nlmsg_data(nlh); info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; info.attrs = attrbuf; + info.dst_sk = skb->sk; genl_info_net_set(&info, net); memset(&info.user_ptr, 0, sizeof(info.user_ptr)); -- cgit v1.2.3-70-g09d2