kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

netlink: update listeners directly when removing socket

Browse source 
The code is now confusing to read - first in one function down
(netlink_remove) any group subscriptions are implicitly removed
by calling __sk_del_bind_node(), but the subscriber database is
only updated far later by calling netlink_update_listeners().

Move the latter call to just after removal from the list so it
is easier to follow the code.

This also enables moving the locking inside the kernel-socket
conditional, which improves the normal socket destruction path.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Johannes Berg 2014-12-22 18:56:37 +01:00 committed by David S. Miller
parent f8403a2e47
commit b10dcb3b94
1 changed files with 5 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
net/netlink/af_netlink.c
View file

@ -1091,8 +1091,10 @@ static void netlink_remove(struct sock *sk)
mutex_unlock(&nl_sk_hash_lock); mutex_unlock(&nl_sk_hash_lock);
netlink_table_grab(); netlink_table_grab();
if (nlk_sk(sk)->subscriptions) if (nlk_sk(sk)->subscriptions) {
__sk_del_bind_node(sk); __sk_del_bind_node(sk);
netlink_update_listeners(sk);
}
netlink_table_ungrab(); netlink_table_ungrab();
} }
@ -1226,8 +1228,8 @@ static int netlink_release(struct socket *sock)
module_put(nlk->module); module_put(nlk->module);
netlink_table_grab();
if (netlink_is_kernel(sk)) { if (netlink_is_kernel(sk)) {
netlink_table_grab();
BUG_ON(nl_table[sk->sk_protocol].registered == 0); BUG_ON(nl_table[sk->sk_protocol].registered == 0);
if (--nl_table[sk->sk_protocol].registered == 0) { if (--nl_table[sk->sk_protocol].registered == 0) {
struct listeners *old; struct listeners *old;
@ -1241,10 +1243,8 @@ static int netlink_release(struct socket *sock)
nl_table[sk->sk_protocol].flags = 0; nl_table[sk->sk_protocol].flags = 0;
nl_table[sk->sk_protocol].registered = 0; nl_table[sk->sk_protocol].registered = 0;
} }
} else if (nlk->subscriptions) { netlink_table_ungrab();
netlink_update_listeners(sk);
} }
netlink_table_ungrab();
kfree(nlk->groups); kfree(nlk->groups);
nlk->groups = NULL; nlk->groups = NULL;