dispatcher: extra sanitize names of environment variables

The DHCP options should already be sanitized. Still, make sure we don't
create a bogus environment.

1 files changed, 26 insertions, 2 deletions

diff --git a/dispatcher/nm-dispatcher-utils.c b/dispatcher/nm-dispatcher-utils.c
index 5e090e2c28..db4d99343c 100644
--- a/dispatcher/nm-dispatcher-utils.c
+++ b/dispatcher/nm-dispatcher-utils.c
@@ -33,6 +33,26 @@
 
 #include "nm-dispatcher-utils.h"
 
+static char *
+_validate_var_name (const char *key)
+{
+	char *sanitized = NULL;
+	nm_assert (key);
+
+	if (!key[0])
+		return NULL;
+
+	sanitized = g_ascii_strup (key, -1);
+	if (!NM_STRCHAR_ALL (sanitized, ch,    (ch >= 'A' && ch <= 'Z')
+	                                    || (ch >= '0' && ch <= '9')
+	                                    || NM_IN_SET (ch, '_'))) {
+		g_free (sanitized);
+		return NULL;
+	}
+
+	return sanitized;
+}
+
 static GSList *
 construct_basic_items (GSList *list,
                        const char *uuid,
@@ -244,7 +264,9 @@ construct_device_dhcp4_items (GSList *items, GVariant *dhcp4_config)
 
 	g_variant_iter_init (&iter, dhcp4_config);
 	while (g_variant_iter_next (&iter, "{&sv}", &key, &val)) {
-		ucased = g_ascii_strup (key, -1);
+		ucased = _validate_var_name (key);
+		if (!ucased)
+			continue;
 		tmp = g_variant_get_string (val, NULL);
 		items = g_slist_prepend (items, g_strdup_printf ("DHCP4_%s=%s", ucased, tmp));
 		g_free (ucased);
@@ -349,7 +371,9 @@ construct_device_dhcp6_items (GSList *items, GVariant *dhcp6_config)
 
 	g_variant_iter_init (&iter, dhcp6_config);
 	while (g_variant_iter_next (&iter, "{&sv}", &key, &val)) {
-		ucased = g_ascii_strup (key, -1);
+		ucased = _validate_var_name (key);
+		if (!ucased)
+			continue;
 		tmp = g_variant_get_string (val, NULL);
 		items = g_slist_prepend (items, g_strdup_printf ("DHCP6_%s=%s", ucased, tmp));
 		g_free (ucased);