diff --git a/ChangeLog b/ChangeLog
index ac4c6778..74e735bb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2015-02-01  Kamil Dudka  <kdudka@redhat.com>
+	* src/files.c (write_lockfile): Avoid writing uninitialized bytes to
+	the lock file -- a simple null_at() would not initialize the buffer.
+
 2015-02-01  Benno Schulenberg  <bensberg@justemail.net>
 	* src/winio.c (do_credits): Add a general entry for all translators.
 	* src/nano.c (version), src/winio.c (do_credits): Update the copyright
diff --git a/src/files.c b/src/files.c
index 3ac53d81..90c6b0cc 100644
--- a/src/files.c
+++ b/src/files.c
@@ -195,7 +195,7 @@ int write_lockfile(const char *lockfilename, const char *origfilename, bool modi
      * our lockfile' message in here...
      *
      * This is likely very wrong, so this is a WIP. */
-    null_at(&lockdata, lockdatalen);
+    memset(lockdata, 0, lockdatalen);
     lockdata[0] = 0x62;
     lockdata[1] = 0x30;
     lockdata[24] = mypid % 256;