netlink: call unbind when releasing socket

Currently, netlink_unbind() is only called when the socket
explicitly unbinds, which limits its usefulness (luckily
there are no users of it yet anyway.)

Call netlink_unbind() also when a socket is released, so it
becomes possible to track listeners with this callback and
without also implementing a netlink notifier (and checking
netlink_has_listeners() in there.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 0 deletions

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 6a9fb7c489a8..f29b63fad932 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1246,6 +1246,13 @@ static int netlink_release(struct socket *sock)
                 netlink_table_ungrab();
         }
 
+        if (nlk->netlink_unbind) {
+                int i;
+
+                for (i = 0; i < nlk->ngroups; i++)
+                        if (test_bit(i, nlk->groups))
+                                nlk->netlink_unbind(i + 1);
+        }
         kfree(nlk->groups);
         nlk->groups = NULL;