set CLOEXEC on diagnostic server FDs (#55850)

* set CLOEXEC on diagnostic server FDs

* Add assert and comment

* fix compiler warning

* simplify asserts to appease all the different builds

Author: John Salem

src/native/eventpipe/ds-ipc-pal-socket.c

@@ -316,11 +316,22 @@ ipc_socket_create_uds (DiagnosticsIpc *ipc)
 	EP_ASSERT (ipc->server_address_family == AF_UNIX);
 
 	ds_ipc_socket_t new_socket = DS_IPC_INVALID_SOCKET;
+	int socket_type = SOCK_STREAM;
+#ifdef SOCK_CLOEXEC
+	socket_type |= SOCK_CLOEXEC;
+#endif // SOCK_CLOEXEC
 	DS_ENTER_BLOCKING_PAL_SECTION;
-	new_socket = socket (ipc->server_address_family, SOCK_STREAM, 0);
+	new_socket = socket (ipc->server_address_family, socket_type, 0);
+#ifndef SOCK_CLOEXEC
+	if (new_socket != DS_IPC_INVALID_SOCKET) {
+		if (fcntl (new_socket, F_SETFD, FD_CLOEXEC) == -1) {
+			EP_ASSERT (!"Failed to set CLOEXEC");
+		}
+	}
+#endif // SOCK_CLOEXEC
 	DS_EXIT_BLOCKING_PAL_SECTION;
 	return new_socket;
-#endif
+#endif // DS_IPC_PAL_AF_UNIX
 	return DS_IPC_INVALID_SOCKET;
 }
 
@@ -337,9 +348,18 @@ ipc_socket_create_tcp (DiagnosticsIpc *ipc)
 #endif
 
 	ds_ipc_socket_t new_socket = DS_IPC_INVALID_SOCKET;
+	int socket_type = SOCK_STREAM;
+#ifdef SOCK_CLOEXEC
+	socket_type |= SOCK_CLOEXEC;
+#endif // SOCK_CLOEXEC
 	DS_ENTER_BLOCKING_PAL_SECTION;
-	new_socket = socket (ipc->server_address_family, SOCK_STREAM, IPPROTO_TCP);
+	new_socket = socket (ipc->server_address_family, socket_type, IPPROTO_TCP);
 	if (new_socket != DS_IPC_INVALID_SOCKET) {
+#ifndef SOCK_CLOEXEC
+		if (fcntl (new_socket, F_SETFD, FD_CLOEXEC) == -1) {
+			EP_ASSERT (!"Failed to set CLOEXEC");
+		}
+#endif // SOCK_CLOEXEC
 		int option_value = 1;
 		setsockopt (new_socket, IPPROTO_TCP, TCP_NODELAY, (const char*)&option_value, sizeof (option_value));
 		if (ipc->mode == DS_IPC_CONNECTION_MODE_LISTEN) {