From 096aa9250edf735b0183a4f439b42cc975e4f17f Mon Sep 17 00:00:00 2001
From: Jason Ish <jason.ish@oisf.net>
Date: Tue, 29 Apr 2025 11:26:46 -0600
Subject: [PATCH] lua/flowvarlib: fix unchecked null

Use checkudata, instead of testudata which won't return in case of
NULL, but raise an error in the Lua script.

Fixes:

** CID 1646748:  Null pointer dereferences  (NULL_RETURNS)
/src/util-lua-flowvarlib.c: 89 in LuaFlowvarValue()
---
 src/util-lua-flowvarlib.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util-lua-flowvarlib.c b/src/util-lua-flowvarlib.c
index 5d49b52ae4..9d80d349bb 100644
--- a/src/util-lua-flowvarlib.c
+++ b/src/util-lua-flowvarlib.c
@@ -81,7 +81,7 @@ static int LuaFlowvarGet(lua_State *L)
 
 static int LuaFlowvarValue(lua_State *L)
 {
-    uint32_t *flowvar_id = luaL_testudata(L, 1, suricata_flowvar_mt);
+    uint32_t *flowvar_id = luaL_checkudata(L, 1, suricata_flowvar_mt);
     Flow *f = LuaStateGetFlow(L);
     if (f == NULL) {
         return LuaCallbackError(L, "flow is NULL");
-- 
2.47.2