swrap: let swrap_sendmsg_before_unix() create a copy of msg_tmp.msg_control

With fd-passing we'll have to modify the content of it.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Anoop C S <anoopcs@samba.org>
Reviewed-by: Andreas Schneider <asn@samba.org>

diff --git a/src/socket_wrapper.c b/src/socket_wrapper.c
index a0eef9d7d6dc8de378f804edd190a4441bb52e59..fa18a09a765ac71260554b5e3cb04eb7942b87e0 100644 (file)
--- a/src/socket_wrapper.c
+++ b/src/socket_wrapper.c
@@ -5151,13 +5151,56 @@ static int swrap_sendmsg_filter_cmsg_sol_socket(const struct cmsghdr *cmsg,
 static int swrap_sendmsg_before_unix(const struct msghdr *_msg_in,
                                     struct msghdr *msg_tmp)
 {
+#ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL
+       struct msghdr *msg_in = discard_const_p(struct msghdr, _msg_in);
+       struct cmsghdr *cmsg = NULL;
+       uint8_t *cm_data = NULL;
+       size_t cm_data_space = 0;
+       int rc = -1;
+
+       *msg_tmp = *msg_in;
+
+       /* Nothing to do */
+       if (msg_in->msg_controllen == 0 || msg_in->msg_control == NULL) {
+               return 0;
+       }
+
+       for (cmsg = CMSG_FIRSTHDR(msg_in);
+            cmsg != NULL;
+            cmsg = CMSG_NXTHDR(msg_in, cmsg)) {
+               switch (cmsg->cmsg_level) {
+               default:
+                       rc = swrap_sendmsg_copy_cmsg(cmsg,
+                                                    &cm_data,
+                                                    &cm_data_space);
+                       break;
+               }
+               if (rc < 0) {
+                       int saved_errno = errno;
+                       SAFE_FREE(cm_data);
+                       errno = saved_errno;
+                       return rc;
+               }
+       }
+
+       msg_tmp->msg_controllen = cm_data_space;
+       msg_tmp->msg_control = cm_data;
+
+       return 0;
+#else /* HAVE_STRUCT_MSGHDR_MSG_CONTROL */
        *msg_tmp = *_msg_in;
        return 0;
+#endif /* ! HAVE_STRUCT_MSGHDR_MSG_CONTROL */
 }
 
 static ssize_t swrap_sendmsg_after_unix(struct msghdr *msg_tmp,
                                        ssize_t ret)
 {
+#ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL
+       int saved_errno = errno;
+       SAFE_FREE(msg_tmp->msg_control);
+       errno = saved_errno;
+#endif /* HAVE_STRUCT_MSGHDR_MSG_CONTROL */
        return ret;
 }