egg: Fix null termination behavior of egg_secure_strndup()

Even if the given string is shorter than n, the result should be null
terminated.  This matches the behavior of strndup().

2 files changed, 26 insertions, 0 deletions

diff --git a/egg/egg-secure-memory.c b/egg/egg-secure-memory.c
index ac4ce06a..4d8b3cc8 100644
--- a/egg/egg-secure-memory.c
+++ b/egg/egg-secure-memory.c
@@ -1344,6 +1344,7 @@ egg_secure_strndup_full (const char *tag,
 	len = length + 1;
 	res = (char *)egg_secure_alloc_full (tag, len, options);
 	memcpy (res, str, len);
+	res[length] = '\0';
 	return res;
 }
 
diff --git a/egg/test-secmem.c b/egg/test-secmem.c
index 58b0d35f..54d81368 100644
--- a/egg/test-secmem.c
+++ b/egg/test-secmem.c
@@ -252,6 +252,30 @@ test_strclear (void)
 	egg_secure_free_full (str, 0);
 }
 
+static void
+test_strndup (void)
+{
+	gchar *str;
+
+	str = egg_secure_strndup ("secret", 6);
+	g_assert (str != NULL);
+	g_assert_cmpuint (strlen (str), ==, 6);
+
+	egg_secure_free_full (str, 0);
+
+	str = egg_secure_strndup ("secret", 10);
+	g_assert (str != NULL);
+	g_assert_cmpuint (strlen (str), ==, 6);
+
+	egg_secure_free_full (str, 0);
+
+	str = egg_secure_strndup ("long secret", 6);
+	g_assert (str != NULL);
+	g_assert_cmpuint (strlen (str), ==, 6);
+
+	egg_secure_free_full (str, 0);
+}
+
 int
 main (int argc, char **argv)
 {
@@ -264,6 +288,7 @@ main (int argc, char **argv)
 	g_test_add_func ("/secmem/multialloc", test_multialloc);
 	g_test_add_func ("/secmem/clear", test_clear);
 	g_test_add_func ("/secmem/strclear", test_strclear);
+	g_test_add_func ("/secmem/strndup", test_strndup);
 
 	return g_test_run ();
 }