# HG changeset patch
# User David Watson <vcs at dbwatson.ukfsn.org>
# Date 1314222596 -3600
# Node ID d1fe52ec2578d2329f48f46d88fbbd2de209dc51
# Parent  b07b0b7517da032fc2237fdab08c923465ae37e3
Restore check for msg->msg_controllen < 0 in cmsg_min_space().

diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
--- a/Modules/socketmodule.c
+++ b/Modules/socketmodule.c
@@ -1749,7 +1749,8 @@ cmsg_min_space(struct msghdr *msg, struc
     static const size_t cmsg_len_end = (offsetof(struct cmsghdr, cmsg_len) +
                                         sizeof(cmsgh->cmsg_len));
 
-    if (cmsgh == NULL || msg->msg_control == NULL)
+    /* Note that POSIX allows msg_controllen to be of signed type. */
+    if (cmsgh == NULL || msg->msg_control == NULL || msg->msg_controllen < 0)
         return 0;
     if (space < cmsg_len_end)
         space = cmsg_len_end;