Use gdb_bfd_ref_ptr in objfile

This changes struct objfile to use a gdb_bfd_ref_ptr.  In addition to
removing some manual memory management, this fixes a use-after-free
that was introduced by the registry rewrite series.  The issue there
was that, in some cases, registry shutdown could refer to memory that
had already been freed.  This help fix the bug by delaying the
destruction of the BFD reference (and thus the per-bfd object) until
after the registry has been shut down.

1 files changed, 14 insertions, 13 deletions

diff --git a/gdb/coffread.c b/gdb/coffread.c
index f7f5bb007ca..45d41d08449 100644
--- a/gdb/coffread.c
+++ b/gdb/coffread.c
@@ -278,7 +278,7 @@ cs_to_bfd_section (struct coff_symbol *cs, struct objfile *objfile)
 
   args.targ_index = cs->c_secnum;
   args.resultp = §
-  bfd_map_over_sections (objfile->obfd, find_targ_sec, &args);
+  bfd_map_over_sections (objfile->obfd.get (), find_targ_sec, &args);
   return sect;
 }
 
@@ -290,7 +290,7 @@ cs_to_section (struct coff_symbol *cs, struct objfile *objfile)
 
   if (sect == NULL)
     return SECT_OFF_TEXT (objfile);
-  return gdb_bfd_section_index (objfile->obfd, sect);
+  return gdb_bfd_section_index (objfile->obfd.get (), sect);
 }
 
 /* Return the address of the section of a COFF symbol.  */
@@ -579,7 +579,8 @@ coff_read_minsyms (file_ptr symtab_offset, unsigned int nsyms,
 		name1 = name + 6;
 	      if (name1 != NULL)
 		{
-		  int lead = bfd_get_symbol_leading_char (objfile->obfd);
+		  int lead
+		    = bfd_get_symbol_leading_char (objfile->obfd.get ());
 		  struct bound_minimal_symbol found;
 
 		  if (lead != '\0' && *name1 == lead)
@@ -610,7 +611,7 @@ static void
 coff_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
 {
   struct coff_symfile_info *info;
-  bfd *abfd = objfile->obfd;
+  bfd *abfd = objfile->obfd.get ();
   coff_data_type *cdata = coff_data (abfd);
   const char *filename = bfd_get_filename (abfd);
   int val;
@@ -655,8 +656,8 @@ coff_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
      FIXME: We should use BFD to read the symbol table, and thus avoid
      this problem.  */
   pe_file =
-    startswith (bfd_get_target (objfile->obfd), "pe")
-    || startswith (bfd_get_target (objfile->obfd), "epoc-pe");
+    startswith (bfd_get_target (objfile->obfd.get ()), "pe")
+    || startswith (bfd_get_target (objfile->obfd.get ()), "epoc-pe");
 
   /* End of warning.  */
 
@@ -742,7 +743,7 @@ coff_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
 	{
 	  gdb_bfd_ref_ptr debug_bfd (symfile_bfd_open (debugfile.c_str ()));
 
-	  symbol_file_add_separate (debug_bfd.get (), debugfile.c_str (),
+	  symbol_file_add_separate (debug_bfd, debugfile.c_str (),
 				    symfile_flags, objfile);
 	}
     }
@@ -817,15 +818,15 @@ coff_symtab_read (minimal_symbol_reader &reader,
      FIXME: Find out if this has been reported to Sun, whether it has
      been fixed in a later release, etc.  */
 
-  bfd_seek (objfile->obfd, 0, 0);
+  bfd_seek (objfile->obfd.get (), 0, 0);
 
   /* Position to read the symbol table.  */
-  val = bfd_seek (objfile->obfd, symtab_offset, 0);
+  val = bfd_seek (objfile->obfd.get (), symtab_offset, 0);
   if (val < 0)
     perror_with_name (objfile_name (objfile));
 
   coffread_objfile = objfile;
-  nlist_bfd_global = objfile->obfd;
+  nlist_bfd_global = objfile->obfd.get ();
   nlist_nsyms_global = nsyms;
   set_last_source_file (NULL);
   memset (opaque_type_chain, 0, sizeof opaque_type_chain);
@@ -1565,7 +1566,7 @@ process_coff_symbol (struct coff_symbol *cs,
   char *name;
 
   name = cs->c_name;
-  name = EXTERNAL_NAME (name, objfile->obfd);
+  name = EXTERNAL_NAME (name, objfile->obfd.get ());
   sym->set_language (get_current_subfile ()->language,
 		     &objfile->objfile_obstack);
   sym->compute_and_set_names (name, true, objfile->per_bfd);
@@ -2001,7 +2002,7 @@ coff_read_struct_type (int index, int length, int lastsym,
     {
       read_one_sym (ms, &sub_sym, &sub_aux);
       name = ms->c_name;
-      name = EXTERNAL_NAME (name, objfile->obfd);
+      name = EXTERNAL_NAME (name, objfile->obfd.get ());
 
       switch (ms->c_sclass)
 	{
@@ -2095,7 +2096,7 @@ coff_read_enum_type (int index, int length, int lastsym,
     {
       read_one_sym (ms, &sub_sym, &sub_aux);
       name = ms->c_name;
-      name = EXTERNAL_NAME (name, objfile->obfd);
+      name = EXTERNAL_NAME (name, objfile->obfd.get ());
 
       switch (ms->c_sclass)
 	{