From: BANADDA <mubarakabanadda68@gmail.com>
Date: Sat, 15 Nov 2025 02:08:10 +0000 (+0000)
Subject: examples/multi-uv: fix invalid req->data access
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c722346518365c401b572f8dbe5fa6792ba923cd;p=thirdparty%2Fcurl.git

examples/multi-uv: fix invalid req->data access

The on_uv_timeout callback was trying to access req->data as
a curl_context pointer, but uv.timeout.data was never initialized,
making it always NULL. This rendered the code inside the if(context)
block unreachable.

Fixes #19462
Closes #19538
---

diff --git a/docs/examples/multi-uv.c b/docs/examples/multi-uv.c
index 190bed3ef4..75fec20199 100644
--- a/docs/examples/multi-uv.c
+++ b/docs/examples/multi-uv.c
@@ -160,12 +160,19 @@ static void on_uv_socket(uv_poll_t *req, int status, int events)
 /* callback from libuv when timeout expires */
 static void on_uv_timeout(uv_timer_t *req)
 {
-  struct curl_context *context = (struct curl_context *) req->data;
-  if(context) {
-    int running_handles;
-    curl_multi_socket_action(context->uv->multi, CURL_SOCKET_TIMEOUT, 0,
-                             &running_handles);
-    check_multi_info(context);
+  /* get the datauv struct from the timer handle */
+  struct datauv *uv = (struct datauv *)req;
+  int running_handles;
+
+  curl_multi_socket_action(uv->multi, CURL_SOCKET_TIMEOUT, 0,
+                           &running_handles);
+
+  /* We do not have a curl_context here, so we need to check messages
+     differently. Create a temporary context just for the check. */
+  if(running_handles) {
+    struct curl_context temp_context;
+    temp_context.uv = uv;
+    check_multi_info(&temp_context);
   }
 }