diff --git a/ChangeLog b/ChangeLog
index 2c5a790d59..32f93689d8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Thu May  7 09:26:50 CEST 2009 Guido Günther <agx@sigxcpu.org>
+
+	* src/util.c (virFileWritePid): check for NULL pointers
+	  to avoid bogus pid files
+	  (virFileReadPid): likewise
+	  (virFileDeletePid): likewise
+
 Thu May  7 09:24:47 CEST 2009 Daniel Veillard <veillard@redhat.com>
 
 	* src/domain_conf.c src/domain_conf.h: parse and save multiple
diff --git a/src/util.c b/src/util.c
index 47a1cd3f45..c5edc9d96e 100644
--- a/src/util.c
+++ b/src/util.c
@@ -1165,6 +1165,11 @@ int virFileWritePid(const char *dir,
     FILE *file = NULL;
     char *pidfile = NULL;
 
+    if (name == NULL || dir == NULL) {
+        rc = EINVAL;
+        goto cleanup;
+    }
+
     if ((rc = virFileMakePath(dir)))
         goto cleanup;
 
@@ -1212,6 +1217,11 @@ int virFileReadPid(const char *dir,
     char *pidfile = NULL;
     *pid = 0;
 
+    if (name == NULL || dir == NULL) {
+        rc = EINVAL;
+        goto cleanup;
+    }
+
     if (!(pidfile = virFilePid(dir, name))) {
         rc = ENOMEM;
         goto cleanup;
@@ -1246,6 +1256,11 @@ int virFileDeletePid(const char *dir,
     int rc = 0;
     char *pidfile = NULL;
 
+    if (name == NULL || dir == NULL) {
+        rc = EINVAL;
+        goto cleanup;
+    }
+
     if (!(pidfile = virFilePid(dir, name))) {
         rc = ENOMEM;
         goto cleanup;