* syscalls.cc (utmp_data): Fix potential buffer overflow.

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 25751d3..fb21b9d 100644 (file)
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,5 +1,9 @@
 2011-01-31  Corinna Vinschen  <corinna@vinschen.de>
 
+       * syscalls.cc (utmp_data): Fix potential buffer overflow.
+
+2011-01-31  Corinna Vinschen  <corinna@vinschen.de>
+
        * fhandler_socket.cc (address_in_use): Improve comment readability.
 
 2011-01-30  Corinna Vinschen  <corinna@vinschen.de>

diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc
index 6ea3c28..825c1cf 100644 (file)
--- a/winsup/cygwin/syscalls.cc
+++ b/winsup/cygwin/syscalls.cc
@@ -3508,7 +3508,7 @@ static struct utmp utmp_data_buf[16];
 static unsigned utix = 0;
 #define nutdbuf (sizeof (utmp_data_buf) / sizeof (utmp_data_buf[0]))
 #define utmp_data ({ \
-  if (utix > nutdbuf) \
+  if (utix >= nutdbuf) \
     utix = 0; \
   utmp_data_buf + utix++; \
 })