Merge pull request #16301 from poettering/firstboot-image

Add --image= switch to firstboot, similar to --root= but with support for operating on disk image

src/shared/mount-util.c

@@ -58,8 +58,8 @@ int umount_recursive(const char *prefix, int flags) {
                         if (!path_startswith(path, prefix))
                                 continue;
 
-                        if (umount2(path, flags) < 0) {
-                                r = log_debug_errno(errno, "Failed to umount %s: %m", path);
+                        if (umount2(path, flags | UMOUNT_NOFOLLOW) < 0) {
+                                log_debug_errno(errno, "Failed to umount %s, ignoring: %m", path);
                                 continue;
                         }
 
@@ -70,7 +70,6 @@ int umount_recursive(const char *prefix, int flags) {
 
                         break;
                 }
-
         } while (again);
 
         return n;

src/shared/mount-util.h

@@ -3,7 +3,9 @@
 
 #include <mntent.h>
 #include <stdio.h>
+#include <unistd.h>
 
+#include "errno-util.h"
 #include "macro.h"
 
 /* 4MB for contents of regular files, 64k inodes for directories, symbolic links and device specials,
@@ -53,3 +55,12 @@ int mount_option_mangle(
                 char **ret_remaining_options);
 
 int mode_to_inaccessible_node(const char *runtime_dir, mode_t mode, char **dest);
+
+/* Useful for usage with _cleanup_(), unmounts, removes a directory and frees the pointer */
+static inline void umount_and_rmdir_and_free(char *p) {
+        PROTECT_ERRNO;
+        (void) umount_recursive(p, 0);
+        (void) rmdir(p);
+        free(p);
+}
+DEFINE_TRIVIAL_CLEANUP_FUNC(char*, umount_and_rmdir_and_free);

src/shared/tests.c

@@ -21,6 +21,7 @@
 #include "env-util.h"
 #include "fs-util.h"
 #include "log.h"
+#include "namespace-util.h"
 #include "path-util.h"
 #include "random-util.h"
 #include "strv.h"
@@ -137,10 +138,7 @@ bool have_namespaces(void) {
 
         if (pid == 0) {
                 /* child */
-                if (unshare(CLONE_NEWNS) < 0)
-                        _exit(EXIT_FAILURE);
-
-                if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0)
+                if (detach_mount_namespace() < 0)
                         _exit(EXIT_FAILURE);
 
                 _exit(EXIT_SUCCESS);