diff --git a/repos/base-linux/run/lx_fs.run b/repos/base-linux/run/lx_fs.run
index ca329f1406..b681e4bc28 100644
--- a/repos/base-linux/run/lx_fs.run
+++ b/repos/base-linux/run/lx_fs.run
@@ -31,7 +31,8 @@ install_config {
 	<default-route>
 		<any-service> <parent/> <any-child/> </any-service>
 	</default-route>
-	<start name="lx_fs">
+	<default caps="100"/>
+	<start name="lx_fs" caps="200">
 		<resource name="RAM" quantum="4M"/>
 		<provides> <service name="File_system"/> </provides>
 		<config> <policy label_prefix="test-libc_vfs" root="/libc_vfs" writeable="yes" /> </config>
@@ -39,12 +40,11 @@ install_config {
 	<start name="test-libc_vfs">
 		<resource name="RAM" quantum="2M"/>
 		<config>
-			<libc stdout="/dev/log">
-				<vfs>
-					<fs />
-					<dir name="dev"> <log/> </dir>
-				</vfs>
-			</libc>
+			<vfs>
+				<fs />
+				<dir name="dev"> <log/> </dir>
+			</vfs>
+			<libc stdout="/dev/log"/>
 		</config>
 	</start>
 </config>
diff --git a/repos/libports/src/test/libc_ffat/main.cc b/repos/libports/src/test/libc_ffat/main.cc
index def23f5ac2..5fb7a26495 100644
--- a/repos/libports/src/test/libc_ffat/main.cc
+++ b/repos/libports/src/test/libc_ffat/main.cc
@@ -120,7 +120,7 @@ static void test(Genode::Xml_node node)
 		CALL_AND_CHECK(ret, mkdir(dir_name, 0777), ((ret == 0) || (errno == EEXIST)), "dir_name=%s", dir_name);
 
 		/* try to create again */
-		CALL_AND_CHECK(ret, mkdir(dir_name, 0777), ((ret == 0) || (errno == EEXIST)), "dir_name=%s", dir_name);
+		CALL_AND_CHECK(ret, mkdir(dir_name, 0777), (errno == EEXIST), "dir_name=%s", dir_name);
 
 		/* change to new directory */
 		CALL_AND_CHECK(ret, chdir(dir_name), ret == 0, "dir_name=%s", dir_name);
diff --git a/repos/os/src/server/lx_fs/directory.h b/repos/os/src/server/lx_fs/directory.h
index c9c2bf7a72..5ae4172b75 100644
--- a/repos/os/src/server/lx_fs/directory.h
+++ b/repos/os/src/server/lx_fs/directory.h
@@ -42,8 +42,16 @@ class File_system::Directory : public Node
 			if (create) {
 				mode_t ugo = S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH;
 				ret = mkdir(path, ugo);
-				if (ret == -1)
-					throw No_space();
+				if (ret == -1) {
+					switch (errno) {
+						case ENAMETOOLONG: throw Name_too_long();
+						case EACCES:       throw Permission_denied();
+						case ENOENT:       throw Lookup_failed();
+						case EEXIST:       throw Node_already_exists();
+						case ENOSPC:
+						default:           throw No_space();
+					}
+				}
 			}
 
 			struct stat s;