X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Fpath-util.c;h=ee87c7493defead6eacea8ee32ad68c4ed0eee38;hb=a75f4e2a02e287294b21ae9e5b1f28b2f8faea39;hp=3256deeec1e3535f25da63c48ba3a978fb49674d;hpb=3542eac7f98e74ca106ac6df81b3b3cb158b35be;p=elogind.git

diff --git a/src/shared/path-util.c b/src/shared/path-util.c
index 3256deeec..ee87c7493 100644
--- a/src/shared/path-util.c
+++ b/src/shared/path-util.c
@@ -458,10 +458,11 @@ int path_is_mount_point(const char *t, bool allow_symlink) {
                 .handle.handle_bytes = MAX_HANDLE_SZ
         };
 
-        int mount_id, mount_id_parent;
+        int mount_id = -1, mount_id_parent = -1;
         _cleanup_free_ char *parent = NULL;
         struct stat a, b;
         int r;
+        bool nosupp = false;
 
         /* We are not actually interested in the file handles, but
          * name_to_handle_at() also passes us the mount ID, hence use
@@ -472,16 +473,19 @@ int path_is_mount_point(const char *t, bool allow_symlink) {
 
         r = name_to_handle_at(AT_FDCWD, t, &h.handle, &mount_id, allow_symlink ? AT_SYMLINK_FOLLOW : 0);
         if (r < 0) {
-                if (IN_SET(errno, ENOSYS, EOPNOTSUPP))
+                if (errno == ENOSYS)
+                        /* This kernel does not support name_to_handle_at()
+                         * fall back to the traditional stat() logic. */
+                        goto fallback;
+                else if (errno == EOPNOTSUPP)
                         /* This kernel or file system does not support
                          * name_to_handle_at(), hence fallback to the
                          * traditional stat() logic */
-                        goto fallback;
-
-                if (errno == ENOENT)
+                        nosupp = true;
+                else if (errno == ENOENT)
                         return 0;
-
-                return -errno;
+                else
+                        return -errno;
         }
 
         r = path_get_parent(t, &parent);
@@ -489,18 +493,23 @@ int path_is_mount_point(const char *t, bool allow_symlink) {
                 return r;
 
         h.handle.handle_bytes = MAX_HANDLE_SZ;
-        r = name_to_handle_at(AT_FDCWD, parent, &h.handle, &mount_id_parent, 0);
-        if (r < 0) {
-                /* The parent can't do name_to_handle_at() but the
-                 * directory we are interested in can? If so, it must
-                 * be a mount point */
+        r = name_to_handle_at(AT_FDCWD, parent, &h.handle, &mount_id_parent, AT_SYMLINK_FOLLOW);
+        if (r < 0)
                 if (errno == EOPNOTSUPP)
-                        return 1;
-
-                return -errno;
-        }
-
-        return mount_id != mount_id_parent;
+                        if (nosupp)
+                                /* Neither parent nor child do name_to_handle_at()?
+                                   We have no choice but to fall back. */
+                                goto fallback;
+                        else
+                                /* The parent can't do name_to_handle_at() but
+                                 * the directory we are interested in can?
+                                 * Or the other way around?
+                                 * If so, it must be a mount point. */
+                                return 1;
+                else
+                        return -errno;
+        else
+                return mount_id != mount_id_parent;
 
 fallback:
         if (allow_symlink)
@@ -515,11 +524,14 @@ fallback:
                 return -errno;
         }
 
+        free(parent);
+        parent = NULL;
+
         r = path_get_parent(t, &parent);
         if (r < 0)
                 return r;
 
-        r = lstat(parent, &b);
+        r = stat(parent, &b);
         if (r < 0)
                 return -errno;