Fix unexpected removal of a directory if it is moved into itself.

Return EINVAL in this situation. It also happens when trying to change
directory name case.

diff --git a/libexfat/node.c b/libexfat/node.c
index cce1de7..bc342b7 100644 (file)
--- a/libexfat/node.c
+++ b/libexfat/node.c
@@ -905,6 +905,23 @@ int exfat_rename(struct exfat* ef, const char* old_path, const char* new_path)
                exfat_put_node(ef, node);
                return rc;
        }
+
+       /* check that target is not a subdirectory of the source */
+       if (node->flags & EXFAT_ATTRIB_DIR)
+       {
+               struct exfat_node* p;
+
+               for (p = dir; p; p = p->parent)
+                       if (node == p)
+                       {
+                               if (existing != NULL)
+                                       exfat_put_node(ef, existing);
+                               exfat_put_node(ef, dir);
+                               exfat_put_node(ef, node);
+                               return -EINVAL;
+                       }
+       }
+
        if (existing != NULL)
        {
                /* remove target if it's not the same node as source */