mach-o reloc size overflow

	* mach-o.c (bfd_mach_o_canonicalize_reloc): Set bfd_error on
	multiply overflow.
diff --git a/bfd/mach-o.c b/bfd/mach-o.c
index 664ff44..bacb1a6 100644
--- a/bfd/mach-o.c
+++ b/bfd/mach-o.c
@@ -1663,7 +1663,10 @@
       size_t amt;
 
       if (_bfd_mul_overflow (asect->reloc_count, sizeof (arelent), &amt))
-	return -1;
+	{
+	  bfd_set_error (bfd_error_file_too_big);
+	  return -1;
+	}
       res = bfd_malloc (amt);
       if (res == NULL)
 	return -1;