diff --git a/extensions/libxt_iface.c b/extensions/libxt_iface.c
index 9033279..07f9cb7 100644
--- a/extensions/libxt_iface.c
+++ b/extensions/libxt_iface.c
@@ -62,7 +62,7 @@ static bool iface_valid_name(const char *name)
 {
 	char invalid_chars[] = ".+!*";
 
-	return !(strlen(name) >= IFNAMSIZ || strcspn(name, invalid_chars) != strlen(name));
+	return strlen(name) < IFNAMSIZ && strpbrk(name, invalid_chars) == NULL;
 }
 
 static void iface_mt_help(void)
diff --git a/extensions/xt_iface.c b/extensions/xt_iface.c
index e0da78e..a30fabf 100644
--- a/extensions/xt_iface.c
+++ b/extensions/xt_iface.c
@@ -42,14 +42,14 @@ static bool xt_iface_mt(const struct sk_buff *skb,
 	bool retval;
 	int i;
 
-	retval =
-	    (dev = dev_get_by_name(&init_net, info->ifname)) != NULL;
+	dev    = dev_get_by_name(&init_net, info->ifname);
+	retval = dev != NULL;
 	if (retval) {
 		for (i = 0; i < XT_IFACE_FLAGCOUNT && retval; ++i) {
 			if (info->flags & xt_iface_lookup[i].iface_flag)
-				retval = retval && (dev->flags & xt_iface_lookup[i].iff_flag);
+				retval &= dev->flags & xt_iface_lookup[i].iff_flag;
 			if (info->invflags & xt_iface_lookup[i].iface_flag)
-				retval = retval && !(dev->flags & xt_iface_lookup[i].iff_flag);
+				retval &= !(dev->flags & xt_iface_lookup[i].iff_flag);
 		}
 		dev_put(dev);
 	}