Add a reference to sunrpc in svc_addsock

commit 2da2c21d7508d34bc6d600df665d84871b65d2b9 upstream.

The svc_addsock function adds transport instances without taking a
reference on the sunrpc.ko module, however, the generic transport
destruction code drops a reference when a transport instance
is destroyed.

Add a try_module_get call to the svc_addsock function for transport
instances added by this function.

Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Tested-by: Jeff Moyer <jmoyer@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 3e65719..e4c27c1 100644 (file)
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -1171,7 +1171,11 @@ int svc_addsock(struct svc_serv *serv,
        else if (so->state > SS_UNCONNECTED)
                err = -EISCONN;
        else {
-               svsk = svc_setup_socket(serv, so, &err, SVC_SOCK_DEFAULTS);
+               if (!try_module_get(THIS_MODULE))
+                       err = -ENOENT;
+               else
+                       svsk = svc_setup_socket(serv, so, &err,
+                                               SVC_SOCK_DEFAULTS);
                if (svsk) {
                        struct sockaddr_storage addr;
                        struct sockaddr *sin = (struct sockaddr *)&addr;
@@ -1184,7 +1188,8 @@ int svc_addsock(struct svc_serv *serv,
                        spin_unlock_bh(&serv->sv_lock);
                        svc_xprt_received(&svsk->sk_xprt);
                        err = 0;
-               }
+               } else
+                       module_put(THIS_MODULE);
        }
        if (err) {
                sockfd_put(so);