cf-socket: don't bypass fclosesocket callback if cancelled before connect

After upgrading to 8.1.2 from 7.84.0, I found that sockets were being
closed without calling the fclosesocket callback if a request was
cancelled after the associated socket was created, but before the socket
was connected. This lead to an imbalance of fopensocket & fclosesocket
callbacks, causing problems with a custom event loop integration using
the multi-API.

This was caused by cf_socket_close() calling sclose() directly instead
of calling socket_close() if the socket was not active. For regular TCP
client connections, the socket is activated by cf_socket_active(), which
is only called when the socket completes the connect.

As far as I can tell, this issue has existed since 7.88.0. That is,
since the code in question was introduced by:
    commit 71b7e0161032927cdfb4e75ea40f65b8898b3956
    Author: Stefan Eissing <stefan@eissing.org>
    Date:   Fri Dec 30 09:14:55 2022 +0100

        lib: connect/h2/h3 refactor

Closes #11439

diff --git a/lib/cf-socket.c b/lib/cf-socket.c
index 0be685216c5d476a603a4221333d7a564bf814e3..5729fe07fad79a2aded993b03ae3910938cd1811 100644 (file)
--- a/lib/cf-socket.c
+++ b/lib/cf-socket.c
@@ -871,7 +871,7 @@ static void cf_socket_close(struct Curl_cfilter *cf, struct Curl_easy *data)
       /* this is our local socket, we did never publish it */
       DEBUGF(LOG_CF(data, cf, "cf_socket_close(%" CURL_FORMAT_SOCKET_T
                     ", not active)", ctx->sock));
-      sclose(ctx->sock);
+      socket_close(data, cf->conn, !ctx->accepted, ctx->sock);
       ctx->sock = CURL_SOCKET_BAD;
     }
     Curl_bufq_reset(&ctx->recvbuf);