From 4f520900522fd596e336c07e9aafd5b7a9564235 Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Tue, 22 Apr 2014 21:31:54 -0400 Subject: netlink: have netlink per-protocol bind function return an error code. Have the netlink per-protocol optional bind function return an int error code rather than void to signal a failure. This will enable netlink protocols to perform extra checks including capabilities and permissions verifications when updating memberships in multicast groups. In netlink_bind() and netlink_setsockopt() the call to the per-protocol bind function was moved above the multicast group update to prevent any access to the multicast socket groups before checking with the per-protocol bind function. This will enable the per-protocol bind function to be used to check permissions which could be denied before making them available, and to avoid the messy job of undoing the addition should the per-protocol bind function fail. The netfilter subsystem seems to be the only one currently using the per-protocol bind function. Signed-off-by: Richard Guy Briggs Signed-off-by: David S. Miller --- net/netlink/af_netlink.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'net/netlink/af_netlink.h') diff --git a/net/netlink/af_netlink.h b/net/netlink/af_netlink.h index ed13a790b00e..0b59d441f5b6 100644 --- a/net/netlink/af_netlink.h +++ b/net/netlink/af_netlink.h @@ -38,7 +38,8 @@ struct netlink_sock { struct mutex *cb_mutex; struct mutex cb_def_mutex; void (*netlink_rcv)(struct sk_buff *skb); - void (*netlink_bind)(int group); + int (*netlink_bind)(int group); + void (*netlink_unbind)(int group); struct module *module; #ifdef CONFIG_NETLINK_MMAP struct mutex pg_vec_lock; @@ -74,7 +75,8 @@ struct netlink_table { unsigned int groups; struct mutex *cb_mutex; struct module *module; - void (*bind)(int group); + int (*bind)(int group); + void (*unbind)(int group); bool (*compare)(struct net *net, struct sock *sock); int registered; }; -- cgit