Commit ffc8fa91 authored by Paolo Abeni's avatar Paolo Abeni
Browse files

Merge branch 'rtnetlink-handle-error-of-rtnl_register_module' 

Kuniyuki Iwashima says:

====================
rtnetlink: Handle error of rtnl_register_module().

While converting phonet to per-netns RTNL, I found a weird comment

  /* Further rtnl_register_module() cannot fail */

that was true but no longer true after commit addf9b90 ("net:
rtnetlink: use rcu to free rtnl message handlers").

Many callers of rtnl_register_module() just ignore the returned
value but should handle them properly.

This series introduces two helpers, rtnl_register_many() and
rtnl_unregister_many(), to do that easily and fix such callers.

All rtnl_register() and rtnl_register_module() will be converted
to _many() variant and some rtnl_lock() will be saved in _many()
later in net-next.

Changes:
  v4:
    * Add more context in changelog of each patch

  v3: https://lore.kernel.org/all/20241007124459.5727-1-kuniyu@amazon.com/
    * Move module *owner to struct rtnl_msg_handler
    * Make struct rtnl_msg_handler args/vars const
    * Update mctp goto labels

  v2: https://lore.kernel.org/netdev/20241004222358.79129-1-kuniyu@amazon.com/
    * Remove __exit from mctp_neigh_exit().

  v1: https://lore.kernel.org/netdev/20241003205725.5612-1-kuniyu@amazon.com/
====================

Link: https://patch.msgid.link/20241008184737.9619-1-kuniyu@amazon.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parents 9a3cd877 b5e837c8

drivers/net/vxlan/vxlan_core.c

+5 −1
Original line number Diff line number Diff line
@@ -4913,9 +4913,13 @@ static int __init vxlan_init_module(void) 
	if (rc)

		goto out4;



	vxlan_vnifilter_init();

	rc = vxlan_vnifilter_init();

	if (rc)

		goto out5;



	return 0;

out5:

	rtnl_link_unregister(&vxlan_link_ops);

out4:

	unregister_switchdev_notifier(&vxlan_switchdev_notifier_block);

out3:

drivers/net/vxlan/vxlan_private.h

+1 −1
Original line number Diff line number Diff line
@@ -202,7 +202,7 @@ int vxlan_vni_in_use(struct net *src_net, struct vxlan_dev *vxlan, 
int vxlan_vnigroup_init(struct vxlan_dev *vxlan);

void vxlan_vnigroup_uninit(struct vxlan_dev *vxlan);



void vxlan_vnifilter_init(void);

int vxlan_vnifilter_init(void);

void vxlan_vnifilter_uninit(void);

void vxlan_vnifilter_count(struct vxlan_dev *vxlan, __be32 vni,

			   struct vxlan_vni_node *vninode,

drivers/net/vxlan/vxlan_vnifilter.c

+9 −10
Original line number Diff line number Diff line
@@ -992,19 +992,18 @@ static int vxlan_vnifilter_process(struct sk_buff *skb, struct nlmsghdr *nlh, 
	return err;

}



void vxlan_vnifilter_init(void)

static const struct rtnl_msg_handler vxlan_vnifilter_rtnl_msg_handlers[] = {

	{THIS_MODULE, PF_BRIDGE, RTM_GETTUNNEL, NULL, vxlan_vnifilter_dump, 0},

	{THIS_MODULE, PF_BRIDGE, RTM_NEWTUNNEL, vxlan_vnifilter_process, NULL, 0},

	{THIS_MODULE, PF_BRIDGE, RTM_DELTUNNEL, vxlan_vnifilter_process, NULL, 0},

};



int vxlan_vnifilter_init(void)

{

	rtnl_register_module(THIS_MODULE, PF_BRIDGE, RTM_GETTUNNEL, NULL,

			     vxlan_vnifilter_dump, 0);

	rtnl_register_module(THIS_MODULE, PF_BRIDGE, RTM_NEWTUNNEL,

			     vxlan_vnifilter_process, NULL, 0);

	rtnl_register_module(THIS_MODULE, PF_BRIDGE, RTM_DELTUNNEL,

			     vxlan_vnifilter_process, NULL, 0);

	return rtnl_register_many(vxlan_vnifilter_rtnl_msg_handlers);

}



void vxlan_vnifilter_uninit(void)

{

	rtnl_unregister(PF_BRIDGE, RTM_GETTUNNEL);

	rtnl_unregister(PF_BRIDGE, RTM_NEWTUNNEL);

	rtnl_unregister(PF_BRIDGE, RTM_DELTUNNEL);

	rtnl_unregister_many(vxlan_vnifilter_rtnl_msg_handlers);

}

include/net/mctp.h

+1 −1
Original line number Diff line number Diff line
@@ -295,7 +295,7 @@ void mctp_neigh_remove_dev(struct mctp_dev *mdev); 
int mctp_routes_init(void);

void mctp_routes_exit(void);



void mctp_device_init(void);

int mctp_device_init(void);

void mctp_device_exit(void);



#endif /* __NET_MCTP_H */

include/net/rtnetlink.h

+17 −0
Original line number Diff line number Diff line
@@ -29,6 +29,15 @@ static inline enum rtnl_kinds rtnl_msgtype_kind(int msgtype) 
	return msgtype & RTNL_KIND_MASK;

}



struct rtnl_msg_handler {

	struct module *owner;

	int protocol;

	int msgtype;

	rtnl_doit_func doit;

	rtnl_dumpit_func dumpit;

	int flags;

};



void rtnl_register(int protocol, int msgtype,

		   rtnl_doit_func, rtnl_dumpit_func, unsigned int flags);

int rtnl_register_module(struct module *owner, int protocol, int msgtype,
@@ -36,6 +45,14 @@ int rtnl_register_module(struct module *owner, int protocol, int msgtype, 
int rtnl_unregister(int protocol, int msgtype);

void rtnl_unregister_all(int protocol);



int __rtnl_register_many(const struct rtnl_msg_handler *handlers, int n);

void __rtnl_unregister_many(const struct rtnl_msg_handler *handlers, int n);



#define rtnl_register_many(handlers)				\

	__rtnl_register_many(handlers, ARRAY_SIZE(handlers))

#define rtnl_unregister_many(handlers)				\

	__rtnl_unregister_many(handlers, ARRAY_SIZE(handlers))



static inline int rtnl_msg_family(const struct nlmsghdr *nlh)

{

	if (nlmsg_len(nlh) >= sizeof(struct rtgenmsg))