Prevent illegal memory access when processing COFF auxillary symbol information.

	PR 23061
	* coffgen.c (coff_pointerize_aux): Add table_end parameter.  Use
	it to prevent walking off the end of the table.
	(coff_get_normalized_symtab): Pass internal_end pointer to
	coff_pointerize_aux.

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index f24ef2b..ae37424 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,11 @@
+2018-08-23  Nick Clifton  <nickc@redhat.com>
+
+       PR 23061
+       * coffgen.c (coff_pointerize_aux): Add table_end parameter.  Use
+       it to prevent walking off the end of the table.
+       (coff_get_normalized_symtab): Pass internal_end pointer to
+       coff_pointerize_aux.
+
 2018-08-23  Alan Modra  <amodra@gmail.com>
 
        * elf64-ppc.c (ppc64_elf_relocate_section): Don't miss clearing

diff --git a/bfd/coffgen.c b/bfd/coffgen.c
index b9e4872..9e62feb 100644 (file)
--- a/bfd/coffgen.c
+++ b/bfd/coffgen.c
@@ -1521,7 +1521,8 @@ coff_pointerize_aux (bfd *abfd,
                     combined_entry_type *table_base,
                     combined_entry_type *symbol,
                     unsigned int indaux,
-                    combined_entry_type *auxent)
+                    combined_entry_type *auxent,
+                    combined_entry_type *table_end)
 {
   unsigned int type = symbol->u.syment.n_type;
   unsigned int n_sclass = symbol->u.syment.n_sclass;
@@ -1549,16 +1550,20 @@ coff_pointerize_aux (bfd *abfd,
        || n_sclass == C_FCN)
       && auxent->u.auxent.x_sym.x_fcnary.x_fcn.x_endndx.l > 0
       && auxent->u.auxent.x_sym.x_fcnary.x_fcn.x_endndx.l
-      < (long) obj_raw_syment_count (abfd))
+      < (long) obj_raw_syment_count (abfd)
+      && table_base + auxent->u.auxent.x_sym.x_fcnary.x_fcn.x_endndx.l
+      < table_end)
     {
       auxent->u.auxent.x_sym.x_fcnary.x_fcn.x_endndx.p =
        table_base + auxent->u.auxent.x_sym.x_fcnary.x_fcn.x_endndx.l;
       auxent->fix_end = 1;
     }
+
   /* A negative tagndx is meaningless, but the SCO 3.2v4 cc can
      generate one, so we must be careful to ignore it.  */
   if ((unsigned long) auxent->u.auxent.x_sym.x_tagndx.l
-      < obj_raw_syment_count (abfd))
+      < obj_raw_syment_count (abfd)
+      && table_base + auxent->u.auxent.x_sym.x_tagndx.l < table_end)
     {
       auxent->u.auxent.x_sym.x_tagndx.p =
        table_base + auxent->u.auxent.x_sym.x_tagndx.l;
@@ -1869,7 +1874,7 @@ coff_get_normalized_symtab (bfd *abfd)
 
          internal_ptr->is_sym = FALSE;
          coff_pointerize_aux (abfd, internal, symbol_ptr, i,
-                              internal_ptr);
+                              internal_ptr, internal_end);
        }
     }