Commit a4c9a56e authored by Anjali Kulkarni's avatar Anjali Kulkarni Committed by David S. Miller
Browse files

netlink: Add new netlink_release function 



A new function netlink_release is added in netlink_sock to store the
protocol's release function. This is called when the socket is deleted.
This can be supplied by the protocol via the release function in
netlink_kernel_cfg. This is being added for the NETLINK_CONNECTOR
protocol, so it can free it's data when socket is deleted.

Signed-off-by: default avatarAnjali Kulkarni <anjali.k.kulkarni@oracle.com>
Reviewed-by: default avatarLiam R. Howlett <Liam.Howlett@oracle.com>
Acked-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a3377386

include/linux/netlink.h

+1 −0
Original line number Diff line number Diff line
@@ -50,6 +50,7 @@ struct netlink_kernel_cfg { 
	struct mutex	*cb_mutex;

	int		(*bind)(struct net *net, int group);

	void		(*unbind)(struct net *net, int group);

	void            (*release) (struct sock *sk, unsigned long *groups);

};



struct sock *__netlink_kernel_create(struct net *net, int unit,

net/netlink/af_netlink.c

+6 −0
Original line number Diff line number Diff line
@@ -677,6 +677,7 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol, 
	struct netlink_sock *nlk;

	int (*bind)(struct net *net, int group);

	void (*unbind)(struct net *net, int group);

	void (*release)(struct sock *sock, unsigned long *groups);

	int err = 0;



	sock->state = SS_UNCONNECTED;
@@ -704,6 +705,7 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol, 
	cb_mutex = nl_table[protocol].cb_mutex;

	bind = nl_table[protocol].bind;

	unbind = nl_table[protocol].unbind;

	release = nl_table[protocol].release;

	netlink_unlock_table();



	if (err < 0)
@@ -719,6 +721,7 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol, 
	nlk->module = module;

	nlk->netlink_bind = bind;

	nlk->netlink_unbind = unbind;

	nlk->netlink_release = release;

out:

	return err;
@@ -763,6 +766,8 @@ static int netlink_release(struct socket *sock) 
	 * OK. Socket is unlinked, any packets that arrive now

	 * will be purged.

	 */

	if (nlk->netlink_release)

		nlk->netlink_release(sk, nlk->groups);



	/* must not acquire netlink_table_lock in any way again before unbind

	 * and notifying genetlink is done as otherwise it might deadlock
@@ -2089,6 +2094,7 @@ __netlink_kernel_create(struct net *net, int unit, struct module *module, 
		if (cfg) {

			nl_table[unit].bind = cfg->bind;

			nl_table[unit].unbind = cfg->unbind;

			nl_table[unit].release = cfg->release;

			nl_table[unit].flags = cfg->flags;

		}

		nl_table[unit].registered = 1;

net/netlink/af_netlink.h

+4 −0
Original line number Diff line number Diff line
@@ -42,6 +42,8 @@ struct netlink_sock { 
	void			(*netlink_rcv)(struct sk_buff *skb);

	int			(*netlink_bind)(struct net *net, int group);

	void			(*netlink_unbind)(struct net *net, int group);

	void			(*netlink_release)(struct sock *sk,

						   unsigned long *groups);

	struct module		*module;



	struct rhash_head	node;
@@ -64,6 +66,8 @@ struct netlink_table { 
	struct module		*module;

	int			(*bind)(struct net *net, int group);

	void			(*unbind)(struct net *net, int group);

	void                    (*release)(struct sock *sk,

					   unsigned long *groups);

	int			registered;

};