diff --git a/ChangeLog b/ChangeLog
index e5b71cf5a..7bae47058 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2013-02-01  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* grub-core/bus/usb/serial/common.c (grub_usbserial_attach): Fix missing
+	zero-out of port structure.
+
 2013-01-30  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/fs/xfs.c (grub_xfs_read_block): Fix computation in presence
diff --git a/grub-core/bus/usb/serial/common.c b/grub-core/bus/usb/serial/common.c
index 55d1884cc..953025963 100644
--- a/grub-core/bus/usb/serial/common.c
+++ b/grub-core/bus/usb/serial/common.c
@@ -51,7 +51,7 @@ grub_usbserial_attach (grub_usb_device_t usbdev, int configno, int interfno,
 
   interf = usbdev->config[configno].interf[interfno].descif;
 
-  port = grub_malloc (sizeof (*port));
+  port = grub_zalloc (sizeof (*port));
   if (!port)
     {
       grub_print_error ();