mount.nfs - require statd to be running to mount without nolocks

If we are mounting nfsv2 or nfsv3 and statd isn't running and we
cannot start statd, then fail the mount request.

Also use an RPC ping to check on statd.

Signed-off-by: Neil Brown <neilb@suse.de>

1 files changed, 46 insertions, 7 deletions

diff --git a/utils/mount/mount.c b/utils/mount/mount.c
index 4698d85..52b0d67 100644
--- a/utils/mount/mount.c
+++ b/utils/mount/mount.c
@@ -302,7 +302,33 @@ static void mount_error(char *node)
 	}
 }
 
-static void start_statd()
+extern u_short getport(
+	struct sockaddr_in *saddr,
+	u_long prog,
+	u_long vers,
+	u_int prot);
+
+static int probe_statd()
+{
+	struct sockaddr_in addr;
+	u_short port;
+
+	memset(&addr, 0, sizeof(addr));
+	addr.sin_family = AF_INET;
+	addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+	port = getport(&addr, 100024, 1, IPPROTO_UDP);
+
+	if (port == 0)
+		return 0;
+	addr.sin_port = htons(port);
+
+	if (clnt_ping(&addr, 100024, 1, IPPROTO_UDP, NULL) <= 0)
+		return 0;
+
+	return 1;
+}
+
+static int start_statd()
 {
 	/* If /var/run/rpc.statd.pid exists and is non-empty,
 	 * assume statd already running.
@@ -311,15 +337,19 @@ static void start_statd()
 	 * else run that file (typically a shell script)
 	 */
 	struct stat stb;
-	if (stat("/var/run/rpc.statd.pid", &stb) == 0 &&
-	    stb.st_size > 0)
-		return;
+
+	if (probe_statd())
+		return 1;
 #ifdef START_STATD
 	if (stat(START_STATD, &stb) ==0 &&
 	    S_ISREG(stb.st_mode) &&
-	    (stb.st_mode & S_IXUSR))
+	    (stb.st_mode & S_IXUSR)) {
 		system(START_STATD);
+		if (probe_statd())
+			return 1;
+	}
 #endif
+	return 0;
 }
 
 int main(int argc, char *argv[])
@@ -485,8 +515,17 @@ int main(int argc, char *argv[])
 		mnt_err = nfsmount(spec, mount_point, &flags,
 				   &extra_opts, &mount_opts,
 				   0, &need_statd);
-		if (!mnt_err && !fake && need_statd)
-			start_statd();
+		if (!mnt_err && !fake && need_statd) {
+			if (!start_statd()) {
+				fprintf(stderr,
+					"%s: rpc.statd is not running but is "
+					"required for remote locking\n"
+					"   Either use \"-o nolocks\" to keep "
+					"locks local, or start statd.\n",
+					progname);
+				exit(1);
+			}
+		}
 	}
 
 	if (mnt_err)