util: rename write_one_line_file() to write_string_file()

[elogind.git] / src / core / machine-id-setup.c

diff --git a/src/core/machine-id-setup.c b/src/core/machine-id-setup.c
index c6fd77ac8dc14b42e37363dfe3d93333b1910a56..51074fea449058b5433f1c80adb10e06a659f2ea 100644 (file)
--- a/src/core/machine-id-setup.c
+++ b/src/core/machine-id-setup.c
@@ -35,6 +35,7 @@
 #include "mkdir.h"
 #include "log.h"
 #include "virt.h"
+#include "fileio.h"
 
 static int shorten_uuid(char destination[36], const char *source) {
         unsigned i, j;
@@ -215,7 +216,7 @@ int machine_id_setup(void) {
          * /run/machine-id as a replacement */
 
         m = umask(0022);
-        r = write_one_line_file("/run/machine-id", id);
+        r = write_string_file("/run/machine-id", id);
         umask(m);
 
         if (r < 0) {
@@ -226,13 +227,19 @@ int machine_id_setup(void) {
         }
 
         /* And now, let's mount it over */
-        r = mount("/run/machine-id", "/etc/machine-id", "bind", MS_BIND|MS_RDONLY, NULL) < 0 ? -errno : 0;
+        r = mount("/run/machine-id", "/etc/machine-id", NULL, MS_BIND, NULL) < 0 ? -errno : 0;
         if (r < 0) {
                 unlink("/run/machine-id");
                 log_error("Failed to mount /etc/machine-id: %s", strerror(-r));
-        } else
+        } else {
                 log_info("Installed transient /etc/machine-id file.");
 
+                /* Mark the mount read-only */
+                if (mount(NULL, "/etc/machine-id", NULL,
+                          MS_BIND|MS_RDONLY|MS_REMOUNT, NULL) < 0)
+                        log_warning("Failed to make transient /etc/machine-id read-only");
+        }
+
 finish:
 
         if (fd >= 0)