1 files changed, 72 insertions, 86 deletions

diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index bb507e2bb94d..9f2f2412a2f3 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -359,7 +359,7 @@ svc_pool_for_cpu(struct svc_serv *serv, int cpu)
  */
 static struct svc_serv *
 __svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
-           sa_family_t family, void (*shutdown)(struct svc_serv *serv))
+             void (*shutdown)(struct svc_serv *serv))
 {
         struct svc_serv *serv;
         unsigned int vers;
@@ -368,7 +368,6 @@ __svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
 
         if (!(serv = kzalloc(sizeof(*serv), GFP_KERNEL)))
                 return NULL;
-        serv->sv_family    = family;
         serv->sv_name      = prog->pg_name;
         serv->sv_program   = prog;
         serv->sv_nrthreads = 1;
@@ -427,21 +426,21 @@ __svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
 
 struct svc_serv *
 svc_create(struct svc_program *prog, unsigned int bufsize,
-                sa_family_t family, void (*shutdown)(struct svc_serv *serv))
+           void (*shutdown)(struct svc_serv *serv))
 {
-        return __svc_create(prog, bufsize, /*npools*/1, family, shutdown);
+        return __svc_create(prog, bufsize, /*npools*/1, shutdown);
 }
 EXPORT_SYMBOL_GPL(svc_create);
 
 struct svc_serv *
 svc_create_pooled(struct svc_program *prog, unsigned int bufsize,
-                  sa_family_t family, void (*shutdown)(struct svc_serv *serv),
+                  void (*shutdown)(struct svc_serv *serv),
                   svc_thread_fn func, struct module *mod)
 {
         struct svc_serv *serv;
         unsigned int npools = svc_pool_map_get();
 
-        serv = __svc_create(prog, bufsize, npools, family, shutdown);
+        serv = __svc_create(prog, bufsize, npools, shutdown);
 
         if (serv != NULL) {
                 serv->sv_function = func;
@@ -719,8 +718,6 @@ svc_exit_thread(struct svc_rqst *rqstp)
 }
 EXPORT_SYMBOL_GPL(svc_exit_thread);
 
-#ifdef CONFIG_SUNRPC_REGISTER_V4
-
 /*
  * Register an "inet" protocol family netid with the local
  * rpcbind daemon via an rpcbind v4 SET request.
@@ -735,12 +732,13 @@ static int __svc_rpcb_register4(const u32 program, const u32 version,
                                 const unsigned short protocol,
                                 const unsigned short port)
 {
-        struct sockaddr_in sin = {
+        const struct sockaddr_in sin = {
                 .sin_family             = AF_INET,
                 .sin_addr.s_addr        = htonl(INADDR_ANY),
                 .sin_port               = htons(port),
         };
-        char *netid;
+        const char *netid;
+        int error;
 
         switch (protocol) {
         case IPPROTO_UDP:
@@ -750,13 +748,23 @@ static int __svc_rpcb_register4(const u32 program, const u32 version,
                 netid = RPCBIND_NETID_TCP;
                 break;
         default:
-                return -EPROTONOSUPPORT;
+                return -ENOPROTOOPT;
         }
 
-        return rpcb_v4_register(program, version,
-                                (struct sockaddr *)&sin, netid);
+        error = rpcb_v4_register(program, version,
+                                        (const struct sockaddr *)&sin, netid);
+
+        /*
+         * User space didn't support rpcbind v4, so retry this
+         * registration request with the legacy rpcbind v2 protocol.
+         */
+        if (error == -EPROTONOSUPPORT)
+                error = rpcb_register(program, version, protocol, port);
+
+        return error;
 }
 
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 /*
  * Register an "inet6" protocol family netid with the local
  * rpcbind daemon via an rpcbind v4 SET request.
@@ -771,12 +779,13 @@ static int __svc_rpcb_register6(const u32 program, const u32 version,
                                 const unsigned short protocol,
                                 const unsigned short port)
 {
-        struct sockaddr_in6 sin6 = {
+        const struct sockaddr_in6 sin6 = {
                 .sin6_family            = AF_INET6,
                 .sin6_addr              = IN6ADDR_ANY_INIT,
                 .sin6_port              = htons(port),
         };
-        char *netid;
+        const char *netid;
+        int error;
 
         switch (protocol) {
         case IPPROTO_UDP:
@@ -786,12 +795,22 @@ static int __svc_rpcb_register6(const u32 program, const u32 version,
                 netid = RPCBIND_NETID_TCP6;
                 break;
         default:
-                return -EPROTONOSUPPORT;
+                return -ENOPROTOOPT;
         }
 
-        return rpcb_v4_register(program, version,
-                                (struct sockaddr *)&sin6, netid);
+        error = rpcb_v4_register(program, version,
+                                        (const struct sockaddr *)&sin6, netid);
+
+        /*
+         * User space didn't support rpcbind version 4, so we won't
+         * use a PF_INET6 listener.
+         */
+        if (error == -EPROTONOSUPPORT)
+                error = -EAFNOSUPPORT;
+
+        return error;
 }
+#endif  /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
 
 /*
  * Register a kernel RPC service via rpcbind version 4.
@@ -799,69 +818,43 @@ static int __svc_rpcb_register6(const u32 program, const u32 version,
  * Returns zero on success; a negative errno value is returned
  * if any error occurs.
  */
-static int __svc_register(const u32 program, const u32 version,
-                          const sa_family_t family,
+static int __svc_register(const char *progname,
+                          const u32 program, const u32 version,
+                          const int family,
                           const unsigned short protocol,
                           const unsigned short port)
 {
-        int error;
+        int error = -EAFNOSUPPORT;
 
         switch (family) {
-        case AF_INET:
-                return __svc_rpcb_register4(program, version,
+        case PF_INET:
+                error = __svc_rpcb_register4(program, version,
                                                 protocol, port);
-        case AF_INET6:
+                break;
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+        case PF_INET6:
                 error = __svc_rpcb_register6(program, version,
                                                 protocol, port);
-                if (error < 0)
-                        return error;
-
-                /*
-                 * Work around bug in some versions of Linux rpcbind
-                 * which don't allow registration of both inet and
-                 * inet6 netids.
-                 *
-                 * Error return ignored for now.
-                 */
-                __svc_rpcb_register4(program, version,
-                                                protocol, port);
-                return 0;
+#endif  /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
         }
 
-        return -EAFNOSUPPORT;
-}
-
-#else   /* CONFIG_SUNRPC_REGISTER_V4 */
-
-/*
- * Register a kernel RPC service via rpcbind version 2.
- *
- * Returns zero on success; a negative errno value is returned
- * if any error occurs.
- */
-static int __svc_register(const u32 program, const u32 version,
-                          sa_family_t family,
-                          const unsigned short protocol,
-                          const unsigned short port)
-{
-        if (family != AF_INET)
-                return -EAFNOSUPPORT;
-
-        return rpcb_register(program, version, protocol, port);
+        if (error < 0)
+                printk(KERN_WARNING "svc: failed to register %sv%u RPC "
+                        "service (errno %d).\n", progname, version, -error);
+        return error;
 }
 
-#endif /* CONFIG_SUNRPC_REGISTER_V4 */
-
 /**
  * svc_register - register an RPC service with the local portmapper
  * @serv: svc_serv struct for the service to register
+ * @family: protocol family of service's listener socket
  * @proto: transport protocol number to advertise
  * @port: port to advertise
  *
- * Service is registered for any address in serv's address family
+ * Service is registered for any address in the passed-in protocol family
  */
-int svc_register(const struct svc_serv *serv, const unsigned short proto,
-                 const unsigned short port)
+int svc_register(const struct svc_serv *serv, const int family,
+                 const unsigned short proto, const unsigned short port)
 {
         struct svc_program      *progp;
         unsigned int            i;
@@ -879,15 +872,15 @@ int svc_register(const struct svc_serv *serv, const unsigned short proto,
                                         i,
                                         proto == IPPROTO_UDP?  "udp" : "tcp",
                                         port,
-                                        serv->sv_family,
+                                        family,
                                         progp->pg_vers[i]->vs_hidden?
                                                 " (but not telling portmap)" : "");
 
                         if (progp->pg_vers[i]->vs_hidden)
                                 continue;
 
-                        error = __svc_register(progp->pg_prog, i,
-                                                serv->sv_family, proto, port);
+                        error = __svc_register(progp->pg_name, progp->pg_prog,
+                                                i, family, proto, port);
                         if (error < 0)
                                 break;
                 }
@@ -896,38 +889,31 @@ int svc_register(const struct svc_serv *serv, const unsigned short proto,
         return error;
 }
 
-#ifdef CONFIG_SUNRPC_REGISTER_V4
-
+/*
+ * If user space is running rpcbind, it should take the v4 UNSET
+ * and clear everything for this [program, version].  If user space
+ * is running portmap, it will reject the v4 UNSET, but won't have
+ * any "inet6" entries anyway.  So a PMAP_UNSET should be sufficient
+ * in this case to clear all existing entries for [program, version].
+ */
 static void __svc_unregister(const u32 program, const u32 version,
                              const char *progname)
 {
-        struct sockaddr_in6 sin6 = {
-                .sin6_family            = AF_INET6,
-                .sin6_addr              = IN6ADDR_ANY_INIT,
-                .sin6_port              = 0,
-        };
         int error;
 
-        error = rpcb_v4_register(program, version,
-                                (struct sockaddr *)&sin6, "");
-        dprintk("svc: %s(%sv%u), error %d\n",
-                        __func__, progname, version, error);
-}
-
-#else   /* CONFIG_SUNRPC_REGISTER_V4 */
+        error = rpcb_v4_register(program, version, NULL, "");
 
-static void __svc_unregister(const u32 program, const u32 version,
-                             const char *progname)
-{
-        int error;
+        /*
+         * User space didn't support rpcbind v4, so retry this
+         * request with the legacy rpcbind v2 protocol.
+         */
+        if (error == -EPROTONOSUPPORT)
+                error = rpcb_register(program, version, 0, 0);
 
-        error = rpcb_register(program, version, 0, 0);
         dprintk("svc: %s(%sv%u), error %d\n",
                         __func__, progname, version, error);
 }
 
-#endif  /* CONFIG_SUNRPC_REGISTER_V4 */
-
 /*
  * All netids, bind addresses and ports registered for [program, version]
  * are removed from the local rpcbind database (if the service is not