SUNRPC: Fix up svc_unregister()

With the new rpcbind code, a PMAP_UNSET will not have any effect on services registered via rpcbind v3 or v4. Implement a version of svc_unregister() that uses an RPCB_UNSET with an empty netid string to make sure we have cleared *all* entries for a kernel RPC service when shutting down, or before starting a fresh instance of the service. Use the new version only when CONFIG_SUNRPC_REGISTER_V4 is enabled; otherwise, the legacy PMAP version is used to ensure complete backwards-compatibility with the Linux portmapper daemon. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

SUNRPC: Fix up svc_unregister()
With the new rpcbind code, a PMAP_UNSET will not have any effect on services registered via rpcbind v3 or v4. Implement a version of svc_unregister() that uses an RPCB_UNSET with an empty netid string to make sure we have cleared *all* entries for a kernel RPC service when shutting down, or before starting a fresh instance of the service. Use the new version only when CONFIG_SUNRPC_REGISTER_V4 is enabled; otherwise, the legacy PMAP version is used to ensure complete backwards-compatibility with the Linux portmapper daemon. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Chuck Lever · J. Bruce Fields
1 parent 9d548b9c95
Showing 1 changed file with 38 additions and 20 deletions Side-by-side Diff
net/sunrpc/svc.c
@@ -896,31 +896,51 @@
 	return error;
 }
  
+#ifdef CONFIG_SUNRPC_REGISTER_V4
+
+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 */
+
+static void __svc_unregister(const u32 program, const u32 version,
+			     const char *progname)
+{
+	int error;
+
+	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 transport protocols and ports for this service are removed
- * from the local rpcbind database if the service is not hidden.
+ * All netids, bind addresses and ports registered for [program, version]
+ * are removed from the local rpcbind database (if the service is not
+ * hidden) to make way for a new instance of the service.
  *
- * The result of unregistration is reported via dprintk for those
- * who want verification of the result, but is otherwise not
- * important.
- *
- * The local rpcbind daemon listens on either only IPv6 or only
- * IPv4.  The kernel can't tell how it's configured.  However,
- * AF_INET addresses are mapped to AF_INET6 in IPv6-only config-
- * urations, so even an unregistration request on AF_INET will
- * get to a local rpcbind daemon listening only on AF_INET6.  So
- * we always unregister via AF_INET.
- *
- * At this point we don't need rpcbind version 4 for unregis-
- * tration:  A v2 UNSET request will clear all transports (netids),
- * addresses, and address families for [program, version].
+ * The result of unregistration is reported via dprintk for those who want
+ * verification of the result, but is otherwise not important.
  */
 static void svc_unregister(const struct svc_serv *serv)
 {
 	struct svc_program *progp;
 	unsigned long flags;
 	unsigned int i;
-	int error;
  
 	clear_thread_flag(TIF_SIGPENDING);
  
@@ -931,9 +951,7 @@
 			if (progp->pg_vers[i]->vs_hidden)
 				continue;
  
-			error = rpcb_register(progp->pg_prog, i, 0, 0);
-			dprintk("svc: svc_unregister(%sv%u), error %d\n",
-					progp->pg_name, i, error);
+			__svc_unregister(progp->pg_prog, i, progp->pg_name);
 		}
 	}
...	...	@@ -896,31 +896,51 @@
896	896	return error;
897	897	}
898	898
	899	+#ifdef CONFIG_SUNRPC_REGISTER_V4
	900	+
	901	+static void __svc_unregister(const u32 program, const u32 version,
	902	+ const char *progname)
	903	+{
	904	+ struct sockaddr_in6 sin6 = {
	905	+ .sin6_family = AF_INET6,
	906	+ .sin6_addr = IN6ADDR_ANY_INIT,
	907	+ .sin6_port = 0,
	908	+ };
	909	+ int error;
	910	+
	911	+ error = rpcb_v4_register(program, version,
	912	+ (struct sockaddr *)&sin6, "");
	913	+ dprintk("svc: %s(%sv%u), error %d\n",
	914	+ __func__, progname, version, error);
	915	+}
	916	+
	917	+#else /* CONFIG_SUNRPC_REGISTER_V4 */
	918	+
	919	+static void __svc_unregister(const u32 program, const u32 version,
	920	+ const char *progname)
	921	+{
	922	+ int error;
	923	+
	924	+ error = rpcb_register(program, version, 0, 0);
	925	+ dprintk("svc: %s(%sv%u), error %d\n",
	926	+ __func__, progname, version, error);
	927	+}
	928	+
	929	+#endif /* CONFIG_SUNRPC_REGISTER_V4 */
	930	+
899	931	/*
900		- * All transport protocols and ports for this service are removed
901		- * from the local rpcbind database if the service is not hidden.
	932	+ * All netids, bind addresses and ports registered for [program, version]
	933	+ * are removed from the local rpcbind database (if the service is not
	934	+ * hidden) to make way for a new instance of the service.
902	935	*
903		- * The result of unregistration is reported via dprintk for those
904		- * who want verification of the result, but is otherwise not
905		- * important.
906		- *
907		- * The local rpcbind daemon listens on either only IPv6 or only
908		- * IPv4. The kernel can't tell how it's configured. However,
909		- * AF_INET addresses are mapped to AF_INET6 in IPv6-only config-
910		- * urations, so even an unregistration request on AF_INET will
911		- * get to a local rpcbind daemon listening only on AF_INET6. So
912		- * we always unregister via AF_INET.
913		- *
914		- * At this point we don't need rpcbind version 4 for unregis-
915		- * tration: A v2 UNSET request will clear all transports (netids),
916		- * addresses, and address families for [program, version].
	936	+ * The result of unregistration is reported via dprintk for those who want
	937	+ * verification of the result, but is otherwise not important.
917	938	*/
918	939	static void svc_unregister(const struct svc_serv *serv)
919	940	{
920	941	struct svc_program *progp;
921	942	unsigned long flags;
922	943	unsigned int i;
923		- int error;
924	944
925	945	clear_thread_flag(TIF_SIGPENDING);
926	946
...	...	@@ -931,9 +951,7 @@
931	951	if (progp->pg_vers[i]->vs_hidden)
932	952	continue;
933	953
934		- error = rpcb_register(progp->pg_prog, i, 0, 0);
935		- dprintk("svc: svc_unregister(%sv%u), error %d\n",
936		- progp->pg_name, i, error);
	954	+ __svc_unregister(progp->pg_prog, i, progp->pg_name);
937	955	}
938	956	}
939	957