Prevent looping in archives

[deliverable/binutils-gdb.git] / bfd / archive.c

diff --git a/bfd/archive.c b/bfd/archive.c
index 1715474ea6cecd9bcdb8378bdf933036139843d6..b3d03d36daf62ddfa40d33fd9bb489172c29c630 100644 (file)
--- a/bfd/archive.c
+++ b/bfd/archive.c
@@ -786,21 +786,29 @@ bfd_openr_next_archived_file (bfd *archive, bfd *last_file)
 bfd *
 bfd_generic_openr_next_archived_file (bfd *archive, bfd *last_file)
 {
-  file_ptr filestart;
+  ufile_ptr filestart;
 
   if (!last_file)
     filestart = bfd_ardata (archive)->first_file_filepos;
   else
     {
-      bfd_size_type size = arelt_size (last_file);
-
       filestart = last_file->proxy_origin;
       if (! bfd_is_thin_archive (archive))
-       filestart += size;
-      /* Pad to an even boundary...
-        Note that last_file->origin can be odd in the case of
-        BSD-4.4-style element with a long odd size.  */
-      filestart += filestart % 2;
+       {
+         bfd_size_type size = arelt_size (last_file);
+
+         filestart += size;
+         /* Pad to an even boundary...
+            Note that last_file->origin can be odd in the case of
+            BSD-4.4-style element with a long odd size.  */
+         filestart += filestart % 2;
+         if (filestart <= last_file->proxy_origin)
+           {
+             /* Prevent looping.  See PR19256.  */
+             bfd_set_error (bfd_error_malformed_archive);
+             return NULL;
+           }
+       }
     }
 
   return _bfd_get_elt_at_filepos (archive, filestart);