cgroup: properly check for ignore-notfound paths (#4803)

[elogind.git] / src / core / cgroup.c

diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index 5ee5bd79555b36cd10cb6619ba60f8ef6fa9e9ac..1e14d9fc416d6f416f8f2c810eb469440c141127 100644 (file)
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -288,14 +288,24 @@ static int lookup_block_device(const char *p, dev_t *dev) {
 static int whitelist_device(const char *path, const char *node, const char *acc) {
         char buf[2+DECIMAL_STR_MAX(dev_t)*2+2+4];
         struct stat st;
+        bool ignore_notfound;
         int r;
 
         assert(path);
         assert(acc);
 
+        if (node[0] == '-') {
+                /* Non-existent paths starting with "-" must be silently ignored */
+                node++;
+                ignore_notfound = true;
+        } else
+                ignore_notfound = false;
+
         if (stat(node, &st) < 0) {
-                log_warning("Couldn't stat device %s", node);
-                return -errno;
+                if (errno == ENOENT && ignore_notfound)
+                        return 0;
+
+                return log_warning_errno(errno, "Couldn't stat device %s: %m", node);
         }
 
         if (!S_ISCHR(st.st_mode) && !S_ISBLK(st.st_mode)) {
@@ -916,8 +926,8 @@ static void cgroup_context_apply(Unit *u, CGroupMask mask, ManagerState state) {
                                 "/dev/pts/ptmx\0" "rw\0" /* /dev/pts/ptmx may not be duplicated, but accessed */
                                 /* Allow /run/elogind/inaccessible/{chr,blk} devices for mapping InaccessiblePaths */
                                 /* Allow /run/systemd/inaccessible/{chr,blk} devices for mapping InaccessiblePaths */
-                                "/run/systemd/inaccessible/chr\0" "rwm\0"
-                                "/run/systemd/inaccessible/blk\0" "rwm\0";
+                                "-/run/systemd/inaccessible/chr\0" "rwm\0"
+                                "-/run/systemd/inaccessible/blk\0" "rwm\0";
 
                         const char *x, *y;