diff --git a/ChangeLog b/ChangeLog
index 93fe8be25..6e9abacf6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2013-10-30  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* grub-core/io/gzio.c (huft_build): Use zalloc for safety.
+	(initialize_tables): reset tl and td to NULL after freeing.
+
 2013-10-28  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/loader/multiboot_mbi2.c: Implement network tag.
diff --git a/grub-core/io/gzio.c b/grub-core/io/gzio.c
index 50dc31ad4..6f93b30e4 100644
--- a/grub-core/io/gzio.c
+++ b/grub-core/io/gzio.c
@@ -544,7 +544,7 @@ huft_build (unsigned *b,	/* code lengths in bits (all assumed <= BMAX) */
 	      z = 1 << j;	/* table entries for j-bit table */
 
 	      /* allocate and link in new table */
-	      q = (struct huft *) grub_malloc ((z + 1) * sizeof (struct huft));
+	      q = (struct huft *) grub_zalloc ((z + 1) * sizeof (struct huft));
 	      if (! q)
 		{
 		  if (h)
@@ -1118,6 +1118,8 @@ initialize_tables (grub_gzio_t gzio)
   /* Reset memory allocation stuff.  */
   huft_free (gzio->tl);
   huft_free (gzio->td);
+  gzio->tl = NULL;
+  gzio->td = NULL;
 }