From 08d6497005939959b7ace7e8e107d4766c5a7795 Mon Sep 17 00:00:00 2001
From: Daniel Stenberg <daniel@haxx.se>
Date: Sat, 7 Mar 2026 11:24:18 +0100
Subject: [PATCH] cf-socket: ignore SOCK_CLOEXEC etc for socktype equality
 checks

As the SOCK_CLOEXEC and SOCK_NONBLOCK get ORed to the socktype, this
introduces the cf_socktype() function to use when checking for the
specific socket type: DGRAM or STREAM. The function filters off the
non-type related bits to enable the comparison.

Follow-up to 05367694ecf24a5d39f

Closes #20808
---
 lib/cf-socket.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/lib/cf-socket.c b/lib/cf-socket.c
index 075ec59dee..4997b581bf 100644
--- a/lib/cf-socket.c
+++ b/lib/cf-socket.c
@@ -1040,6 +1040,19 @@ static CURLcode set_remote_ip(struct Curl_cfilter *cf,
   return CURLE_OK;
 }
 
+/* to figure out the type of the socket safely, remove the possibly ORed
+   bits before comparing */
+static int cf_socktype(int x)
+{
+#ifdef SOCK_CLOEXEC
+  x &= ~SOCK_CLOEXEC;
+#endif
+#ifdef SOCK_NONBLOCK
+  x &= ~SOCK_NONBLOCK;
+#endif
+  return x;
+}
+
 static CURLcode cf_socket_open(struct Curl_cfilter *cf,
                                struct Curl_easy *data)
 {
@@ -1095,10 +1108,10 @@ static CURLcode cf_socket_open(struct Curl_cfilter *cf,
 #ifdef USE_IPV6
   is_tcp = (ctx->addr.family == AF_INET ||
             ctx->addr.family == AF_INET6) &&
-           ctx->addr.socktype == SOCK_STREAM;
+    cf_socktype(ctx->addr.socktype) == SOCK_STREAM;
 #else
   is_tcp = (ctx->addr.family == AF_INET) &&
-           ctx->addr.socktype == SOCK_STREAM;
+    cf_socktype(ctx->addr.socktype) == SOCK_STREAM;
 #endif
   if(is_tcp && data->set.tcp_nodelay)
     tcpnodelay(cf, data, ctx->sock);
@@ -1163,7 +1176,7 @@ static CURLcode cf_socket_open(struct Curl_cfilter *cf,
     }
   }
 #endif
-  ctx->sock_connected = (ctx->addr.socktype != SOCK_DGRAM);
+  ctx->sock_connected = (cf_socktype(ctx->addr.socktype) != SOCK_DGRAM);
 out:
   if(result) {
     if(ctx->sock != CURL_SOCKET_BAD) {