main: correctly mark the last_layer with a deleted directory

Closes: #136 Signed-off-by: Giuseppe Scrivano <[email protected]>
containers · Oct 31, 2019 · 978ecd2 · 978ecd2
1 parent 715a95c
commit 978ecd2
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Showing 2 changed files with 50 additions and 16 deletions.
diff --git a/main.c b/main.c
@@ -1152,7 +1152,7 @@ make_ovl_node (struct ovl_data *lo, const char *path, struct ovl_layer *layer, c
       return NULL;
 
   ret->parent = parent;
-  ret->layer = layer;
+  ret->last_layer = ret->layer = layer;
   ret->tmp_ino = ino;
   ret->tmp_dev = dev;
   ret->hidden_dirfd = -1;
@@ -1187,11 +1187,17 @@ make_ovl_node (struct ovl_data *lo, const char *path, struct ovl_layer *layer, c
       struct stat st;
       struct ovl_layer *it;
       cleanup_free char *npath = NULL;
+      char whiteout_path[PATH_MAX];
 
       npath = strdup (ret->path);
       if (npath == NULL)
         return NULL;
 
+      if (parent)
+        strconcat3 (whiteout_path, PATH_MAX, parent->path, "/.wh.", name);
+      else
+        strconcat3 (whiteout_path, PATH_MAX, "/.wh.", name, NULL);
+
       for (it = layer; it; it = it->next)
         {
           ssize_t s;
@@ -1200,6 +1206,18 @@ make_ovl_node (struct ovl_data *lo, const char *path, struct ovl_layer *layer, c
           cleanup_free char *origin = NULL;
           cleanup_close int fd = -1;
 
+          if (dir_p)
+            {
+              int r;
+
+              r = it->ds->file_exists (it, whiteout_path);
+              if (r < 0 && errno != ENOENT)
+                return NULL;
+
+              if (r == 0)
+                break;
+            }
+
           if (! fast_ino_check)
             fd = it->ds->openat (it, npath, O_RDONLY|O_NONBLOCK|O_NOFOLLOW, 0755);
 
@@ -1348,6 +1366,7 @@ static struct ovl_node *
 load_dir (struct ovl_data *lo, struct ovl_node *n, struct ovl_layer *layer, char *path, char *name)
 {
   struct dirent *dent;
+  bool stop_lookup = false;
   struct ovl_layer *it, *upper_layer = get_upper_layer (lo);
 
   if (!n)
@@ -1360,10 +1379,13 @@ load_dir (struct ovl_data *lo, struct ovl_node *n, struct ovl_layer *layer, char
         }
     }
 
-  for (it = lo->layers; it; it = it->next)
+  for (it = lo->layers; it && !stop_lookup; it = it->next)
     {
       DIR *dp = NULL;
 
+      if (n->last_layer == it)
+        stop_lookup = true;
+
       dp = it->ds->opendir (it, path);
       if (dp == NULL)
         continue;
@@ -1397,7 +1419,6 @@ load_dir (struct ovl_data *lo, struct ovl_node *n, struct ovl_layer *layer, char
           child = hash_lookup (n->children, &key);
           if (child)
             {
-              child->last_layer = it;
               if (!child->whiteout || it != upper_layer)
                 continue;
               else
@@ -1481,16 +1502,13 @@ load_dir (struct ovl_data *lo, struct ovl_node *n, struct ovl_layer *layer, char
                 }
             }
 
-            if (insert_node (n, child, false) == NULL)
-              {
-                errno = ENOMEM;
-                it->ds->closedir (dp);
-                return NULL;
-              }
+          if (insert_node (n, child, false) == NULL)
+            {
+              errno = ENOMEM;
+              it->ds->closedir (dp);
+              return NULL;
+            }
         }
-
-      if (n->last_layer == it)
-        break;
     }
 
   if (get_timeout (lo) > 0)
@@ -1685,14 +1703,18 @@ do_lookup_file (struct ovl_data *lo, fuse_ino_t parent, const char *name)
       int ret;
       struct ovl_layer *it;
       struct stat st;
+      bool stop_lookup = false;
       struct ovl_layer *upper_layer = get_upper_layer (lo);
 
-      for (it = lo->layers; it; it = it->next)
+      for (it = lo->layers; it && !stop_lookup; it = it->next)
         {
           char path[PATH_MAX];
           char whpath[PATH_MAX];
           const char *wh_name;
 
+          if (pnode && pnode->last_layer == it)
+            stop_lookup = true;
+
           strconcat3 (path, PATH_MAX, pnode->path, "/", name);
 
           ret = it->ds->statat (it, path, &st, AT_SYMLINK_NOFOLLOW, STATX_TYPE|STATX_MODE|STATX_INO);
@@ -1773,9 +1795,6 @@ do_lookup_file (struct ovl_data *lo, fuse_ino_t parent, const char *name)
               errno = ENOMEM;
               return NULL;
             }
-
-          if (pnode && pnode->last_layer == it)
-            break;
         }
     }
 

diff --git a/tests/fedora-installs.sh b/tests/fedora-installs.sh
@@ -83,3 +83,18 @@ touch merged/usr 2>&1 | grep Read-only
 mkdir merged/abcd12345 2>&1 | grep Read-only
 ln merged/file-lower-layer merged/file-lower-layer-link 2>&1 | grep Read-only
 ln -s merged/file-lower-layer merged/a-symlink 2>&1 | grep Read-only
+
+umount merged
+
+# https://github.com/containers/fuse-overlayfs/issues/136
+rm -rf lower1 lower2 lower3 lower upper workdir merged
+mkdir lower1 lower2 lower3 upper workdir merged
+
+mkdir -p lower1/dir1/dir2
+touch lower1/dir1/dir2/foo
+touch lower2/.wh.dir1
+mkdir -p lower3/dir1/dir2
+
+fuse-overlayfs -o lowerdir=lower3:lower2:lower1,upperdir=upper,workdir=workdir merged
+
+test \! -e merged/dir1/dir2/foo