PR25078, stack overflow in function find_abstract_instance

	PR 25078
	* dwarf2.c (find_abstract_instance): Delete orig_info_ptr, add
	recur_count.  Error on recur_count reaching 100 rather than
	info_ptr matching orig_info_ptr.  Adjust calls.

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 6062d38a28dc78a75595a3a043b69a9d8be63e76..cf5b372860359e1ef9f7ecd262c00b86db94c17d 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,10 @@
+2019-10-08  Alan Modra  <amodra@gmail.com>
+
+       PR 25078
+       * dwarf2.c (find_abstract_instance): Delete orig_info_ptr, add
+       recur_count.  Error on recur_count reaching 100 rather than
+       info_ptr matching orig_info_ptr.  Adjust calls.
+
 2019-10-07  Jozef Lawrynowicz  <jozef.l@mittosystems.com>
 
        * elf32-msp430.c (elf32_msp430_merge_mspabi_attributes): Rename to..

diff --git a/bfd/dwarf2.c b/bfd/dwarf2.c
index 575b082e1dcbff689f04d1bfca84f63b2e45f7b6..d39f4fdfe4b8bc3d3e9bbbd691c59b6abb6a3255 100644 (file)
--- a/bfd/dwarf2.c
+++ b/bfd/dwarf2.c
@@ -2812,13 +2812,13 @@ static bfd_boolean comp_unit_maybe_decode_line_info (struct comp_unit *,
                                                     struct dwarf2_debug *);
 
 static bfd_boolean
-find_abstract_instance (struct comp_unit *   unit,
-                       bfd_byte *           orig_info_ptr,
-                       struct attribute *   attr_ptr,
-                       const char **        pname,
-                       bfd_boolean *        is_linkage,
-                       char **              filename_ptr,
-                       int *                linenumber_ptr)
+find_abstract_instance (struct comp_unit *unit,
+                       struct attribute *attr_ptr,
+                       unsigned int recur_count,
+                       const char **pname,
+                       bfd_boolean *is_linkage,
+                       char **filename_ptr,
+                       int *linenumber_ptr)
 {
   bfd *abfd = unit->abfd;
   bfd_byte *info_ptr;
@@ -2829,6 +2829,14 @@ find_abstract_instance (struct comp_unit *   unit,
   struct attribute attr;
   const char *name = NULL;
 
+  if (recur_count == 100)
+    {
+      _bfd_error_handler
+       (_("DWARF error: abstract instance recursion detected"));
+      bfd_set_error (bfd_error_bad_value);
+      return FALSE;
+    }
+
   /* DW_FORM_ref_addr can reference an entry in a different CU. It
      is an offset from the .debug_info section, not the current CU.  */
   if (attr_ptr->form == DW_FORM_ref_addr)
@@ -2962,15 +2970,6 @@ find_abstract_instance (struct comp_unit *   unit,
                                         info_ptr, info_ptr_end);
              if (info_ptr == NULL)
                break;
-             /* It doesn't ever make sense for DW_AT_specification to
-                refer to the same DIE.  Stop simple recursion.  */
-             if (info_ptr == orig_info_ptr)
-               {
-                 _bfd_error_handler
-                   (_("DWARF error: abstract instance recursion detected"));
-                 bfd_set_error (bfd_error_bad_value);
-                 return FALSE;
-               }
              switch (attr.name)
                {
                case DW_AT_name:
@@ -2984,7 +2983,7 @@ find_abstract_instance (struct comp_unit *   unit,
                    }
                  break;
                case DW_AT_specification:
-                 if (!find_abstract_instance (unit, info_ptr, &attr,
+                 if (!find_abstract_instance (unit, &attr, recur_count + 1,
                                               &name, is_linkage,
                                               filename_ptr, linenumber_ptr))
                    return FALSE;
@@ -3200,7 +3199,7 @@ scan_unit_for_symbols (struct comp_unit *unit)
 
                case DW_AT_abstract_origin:
                case DW_AT_specification:
-                 if (!find_abstract_instance (unit, info_ptr, &attr,
+                 if (!find_abstract_instance (unit, &attr, 0,
                                               &func->name,
                                               &func->is_linkage,
                                               &func->file,