Commit 1797754e authored by Thomas Graf's avatar Thomas Graf Committed by David S. Miller
Browse files

[NETLINK]: Introduce NLMSG_NEW macro to better handle netlink flags 



Introduces a new macro NLMSG_NEW which extends NLMSG_PUT but takes
a flags argument. NLMSG_PUT stays there for compatibility but now
calls NLMSG_NEW with flags == 0. NLMSG_PUT_ANSWER is renamed to
NLMSG_NEW_ANSWER which now also takes a flags argument.

Also converts the users of NLMSG_PUT_ANSWER to use NLMSG_NEW_ANSWER
and fixes the two direct users of __nlmsg_put to either provide
the flags or use NLMSG_NEW(_ANSWER).

Signed-off-by: default avatarThomas Graf <tgraf@suug.ch>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent af0d1141

include/linux/netlink.h

+10 −7
Original line number Diff line number Diff line
@@ -156,7 +156,7 @@ struct netlink_notify 
};



static __inline__ struct nlmsghdr *

__nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len)

__nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags)

{

	struct nlmsghdr *nlh;

	int size = NLMSG_LENGTH(len);
@@ -164,20 +164,23 @@ __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len) 
	nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));

	nlh->nlmsg_type = type;

	nlh->nlmsg_len = size;

	nlh->nlmsg_flags = 0;

	nlh->nlmsg_flags = flags;

	nlh->nlmsg_pid = pid;

	nlh->nlmsg_seq = seq;

	return nlh;

}



#define NLMSG_PUT(skb, pid, seq, type, len) \

#define NLMSG_NEW(skb, pid, seq, type, len, flags) \

({	if (skb_tailroom(skb) < (int)NLMSG_SPACE(len)) \

		goto nlmsg_failure; \

	__nlmsg_put(skb, pid, seq, type, len); })

	__nlmsg_put(skb, pid, seq, type, len, flags); })



#define NLMSG_PUT(skb, pid, seq, type, len) \

	NLMSG_NEW(skb, pid, seq, type, len, 0)



#define NLMSG_PUT_ANSWER(skb, cb, type, len) \

	NLMSG_PUT(skb, NETLINK_CB((cb)->skb).pid, \

		  (cb)->nlh->nlmsg_seq, type, len)

#define NLMSG_NEW_ANSWER(skb, cb, type, len, flags) \

	NLMSG_NEW(skb, NETLINK_CB((cb)->skb).pid, \

		  (cb)->nlh->nlmsg_seq, type, len, flags)



#define NLMSG_END(skb, nlh) \

({	(nlh)->nlmsg_len = (skb)->tail - (unsigned char *) (nlh); \

net/core/neighbour.c

+4 −4
Original line number Diff line number Diff line
@@ -1590,8 +1590,8 @@ static int neightbl_fill_info(struct neigh_table *tbl, struct sk_buff *skb, 
	struct nlmsghdr *nlh;

	struct ndtmsg *ndtmsg;



	nlh = NLMSG_PUT_ANSWER(skb, cb, RTM_NEWNEIGHTBL, sizeof(struct ndtmsg));

	nlh->nlmsg_flags |= NLM_F_MULTI;

	nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWNEIGHTBL, sizeof(struct ndtmsg),

			       NLM_F_MULTI);



	ndtmsg = NLMSG_DATA(nlh);
@@ -1675,8 +1675,8 @@ static int neightbl_fill_param_info(struct neigh_table *tbl, 
	struct ndtmsg *ndtmsg;

	struct nlmsghdr *nlh;



	nlh = NLMSG_PUT_ANSWER(skb, cb, RTM_NEWNEIGHTBL, sizeof(struct ndtmsg));

	nlh->nlmsg_flags |= NLM_F_MULTI;

	nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWNEIGHTBL, sizeof(struct ndtmsg),

			       NLM_F_MULTI);



	ndtmsg = NLMSG_DATA(nlh);

net/netlink/af_netlink.c

+5 −3
Original line number Diff line number Diff line
@@ -1095,8 +1095,7 @@ static int netlink_dump(struct sock *sk) 
		return 0;

	}



	nlh = __nlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq, NLMSG_DONE, sizeof(int));

	nlh->nlmsg_flags |= NLM_F_MULTI;

	nlh = NLMSG_NEW_ANSWER(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI);

	memcpy(NLMSG_DATA(nlh), &len, sizeof(len));

	skb_queue_tail(&sk->sk_receive_queue, skb);

	sk->sk_data_ready(sk, skb->len);
@@ -1107,6 +1106,9 @@ static int netlink_dump(struct sock *sk) 


	netlink_destroy_callback(cb);

	return 0;



nlmsg_failure:

	return -ENOBUFS;

}



int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
@@ -1178,7 +1180,7 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err) 
	}



	rep = __nlmsg_put(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,

			  NLMSG_ERROR, sizeof(struct nlmsgerr));

			  NLMSG_ERROR, sizeof(struct nlmsgerr), 0);

	errmsg = NLMSG_DATA(rep);

	errmsg->error = err;

	memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(struct nlmsghdr));

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