diff mbox series

[v7,2/6] netlink: Add new netlink_release function

Message ID	20230704001136.2301645-3-anjali.k.kulkarni@oracle.com
State	New
Headers	Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; From: Anjali Kulkarni <anjali.k.kulkarni@oracle.com> To: davem@davemloft.net Cc: david@fries.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, zbr@ioremap.net, brauner@kernel.org, johannes@sipsolutions.net, ecree.xilinx@gmail.com, leon@kernel.org, keescook@chromium.org, socketcan@hartkopp.net, petrm@nvidia.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, anjali.k.kulkarni@oracle.com Subject: [PATCH v7 2/6] netlink: Add new netlink_release function Date: Mon, 3 Jul 2023 17:11:32 -0700 Message-ID: <20230704001136.2301645-3-anjali.k.kulkarni@oracle.com> In-Reply-To: <20230704001136.2301645-1-anjali.k.kulkarni@oracle.com> References: <20230704001136.2301645-1-anjali.k.kulkarni@oracle.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	Process connector bug fixes & enhancements \| [v7,0/6] Process connector bug fixes & enhancements [v7,1/6] netlink: Reverse the patch which removed filtering [v7,2/6] netlink: Add new netlink_release function [v7,3/6] connector/cn_proc: Add filtering to fix some bugs [v7,4/6] connector/cn_proc: Performance improvements [v7,5/6] connector/cn_proc: Allow non-root users access [v7,6/6] connector/cn_proc: Selftest for proc connector

Commit Message

Anjali Kulkarni July 4, 2023, 12:11 a.m. UTC

  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: Anjali Kulkarni <anjali.k.kulkarni@oracle.com>
---
 include/linux/netlink.h  | 1 +
 net/netlink/af_netlink.c | 6 ++++++
 net/netlink/af_netlink.h | 4 ++++
 3 files changed, 11 insertions(+)

Comments

Liam R. Howlett July 7, 2023, 2 p.m. UTC | #1

* Anjali Kulkarni <anjali.k.kulkarni@oracle.com> [691231 23:00]:
> 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: Anjali Kulkarni <anjali.k.kulkarni@oracle.com>

Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>

> ---
>  include/linux/netlink.h  | 1 +
>  net/netlink/af_netlink.c | 6 ++++++
>  net/netlink/af_netlink.h | 4 ++++
>  3 files changed, 11 insertions(+)
> 
> diff --git a/include/linux/netlink.h b/include/linux/netlink.h
> index d73cfe5b6bc2..0db4ffe6186b 100644
> --- a/include/linux/netlink.h
> +++ b/include/linux/netlink.h
> @@ -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,
> diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
> index e75e5156e4ac..383c10c6e6e3 100644
> --- a/net/netlink/af_netlink.c
> +++ b/net/netlink/af_netlink.c
> @@ -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
> @@ -2091,6 +2096,7 @@ __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;
> diff --git a/net/netlink/af_netlink.h b/net/netlink/af_netlink.h
> index 90a3198a9b7f..fd424cd63f31 100644
> --- a/net/netlink/af_netlink.h
> +++ b/net/netlink/af_netlink.h
> @@ -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;
>  };
>  
> -- 
> 2.41.0
>

diff mbox series

Patch

diff --git a/include/linux/netlink.h b/include/linux/netlink.h
index d73cfe5b6bc2..0db4ffe6186b 100644
--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h
@@ -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,
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index e75e5156e4ac..383c10c6e6e3 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -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
@@ -2091,6 +2096,7 @@  __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;
diff --git a/net/netlink/af_netlink.h b/net/netlink/af_netlink.h
index 90a3198a9b7f..fd424cd63f31 100644
--- a/net/netlink/af_netlink.h
+++ b/net/netlink/af_netlink.h
@@ -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;
 };