[rtems commit] libtests/termios04: Avoid NULL pointer access

[Sebastian Huber]

Module:    rtems
Branch:    master
Commit:    d9998172a062d1d8b730b4d3cae10f3876e967e5
Changeset: http://git.rtems.org/rtems/commit/?id=d9998172a062d1d8b730b4d3cae10f3876e967e5

Author:    Sebastian Huber <sebastian.huber at embedded-brains.de>
Date:      Tue Sep 17 13:48:30 2013 +0200

libtests/termios04: Avoid NULL pointer access

---

 .../libtests/termios04/termios_testdriver_intr.c   |    9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/testsuites/libtests/termios04/termios_testdriver_intr.c b/testsuites/libtests/termios04/termios_testdriver_intr.c
index 72a5f9e..d7d1d9e 100644
--- a/testsuites/libtests/termios04/termios_testdriver_intr.c
+++ b/testsuites/libtests/termios04/termios_testdriver_intr.c
@@ -153,9 +153,12 @@ ssize_t termios_test_driver_write_helper(
   size_t      len
 )
 {
-  Tx_Buffer[Tx_Index++] = buf[0];
-  (void) rtems_timer_fire_after( Tx_Timer, 10, Tx_ISR, NULL );
-  return 1;
+  if (len > 0) {
+    Tx_Buffer[Tx_Index++] = buf[0];
+    (void) rtems_timer_fire_after( Tx_Timer, 10, Tx_ISR, NULL );
+  }
+
+  return 0;
 }
 
 /*