[PATCH v4 2/6] netlink: Add new netlink_release function
From: Anjali Kulkarni <hidden>
Date: 2023-03-31 23:55:56
Also in:
lkml
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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 <redacted> --- 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 866bbc5a4c8d..05a316aa93b4 100644
--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h@@ -51,6 +51,7 @@ struct netlink_kernel_cfg { int (*bind)(struct net *net, int group); void (*unbind)(struct net *net, int group); bool (*compare)(struct net *net, struct sock *sk); + 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 003c7e6ec9be..dc7880055705 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
@@ -2117,6 +2122,7 @@ __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; if (cfg->compare) nl_table[unit].compare = cfg->compare;
diff --git a/net/netlink/af_netlink.h b/net/netlink/af_netlink.h
index 5f454c8de6a4..054335a34804 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;
@@ -65,6 +67,8 @@ struct netlink_table { int (*bind)(struct net *net, int group); void (*unbind)(struct net *net, int group); bool (*compare)(struct net *net, struct sock *sock); + void (*release)(struct sock *sk, + unsigned long *groups); int registered; };
--
2.40.0