core: check null_or_empty for masked units instead of /dev/null

There's some inconsistency in the what is considered a masked unit:
some places (i.e. load-fragment.c) use `null_or_empty()` while others
check if the file path is symlinked to "/dev/null". Since the latter
doesn't account for things like non-absolute symlinks to "/dev/null",
this commit switches the check for "/dev/null" to use `null_or_empty_path()`

1 files changed, 1 insertions, 1 deletions

diff --git a/src/core/unit.c b/src/core/unit.c
index 18bf0cd52a..c739c0a561 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -5955,7 +5955,7 @@ const char *unit_label_path(const Unit *u) {
                 return NULL;
 
         /* If a unit is masked, then don't read the SELinux label of /dev/null, as that really makes no sense */
-        if (path_equal(p, "/dev/null"))
+        if (null_or_empty_path(p) > 0)
                 return NULL;
 
         return p;