[newlib-cygwin] Cygwin: honor SOCK_NONBLOCK/SOCK_CLOEXEC in socket(2)/socketpair(2)

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=535903696c339b71edd3575ab44bbf2e5eab689a

commit 535903696c339b71edd3575ab44bbf2e5eab689a
Author: Corinna Vinschen <corinna@vinschen.de>
Date:   Mon Nov 5 21:02:22 2018 +0100

    Cygwin: honor SOCK_NONBLOCK/SOCK_CLOEXEC in socket(2)/socketpair(2)
    
    fhandler_socket_wsock::set_socket_handle calls set_flags after
    setting the O_NONBLOCK/O_CLOEXEC flags, thus overwriting them.
    
    It also turns out that fhandler_socket_wsock::init_events is called
    too late.  The inheritence flags are changed before creating the
    socket event handling objects.  Thus, inheritence flags for
    those objects are wrong with SOCK_CLOEXEC.
    
    Fix this by reordering the calls and setting the file flags through
    fhandler_base::set_flags.
    
    Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

Diff:
---
 winsup/cygwin/fhandler_socket_inet.cc | 16 ++++++++++------
 winsup/cygwin/release/2.11.2          |  4 ++++
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/winsup/cygwin/fhandler_socket_inet.cc b/winsup/cygwin/fhandler_socket_inet.cc
index 63abf73..dbfbcf5 100644
--- a/winsup/cygwin/fhandler_socket_inet.cc
+++ b/winsup/cygwin/fhandler_socket_inet.cc
@@ -592,6 +592,7 @@ fhandler_socket_wsock::set_socket_handle (SOCKET sock, int af, int type,
 {
   DWORD hdl_flags;
   bool lsp_fixup = false;
+  int file_flags = O_RDWR | O_BINARY;
 
   /* Usually sockets are inheritable IFS objects.  Unfortunately some virus
      scanners or other network-oriented software replace normal sockets
@@ -644,18 +645,21 @@ fhandler_socket_wsock::set_socket_handle (SOCKET sock, int af, int type,
             }
         }
     }
+  set_io_handle ((HANDLE) sock);
   set_addr_family (af);
   set_socket_type (type);
-  if (flags & SOCK_NONBLOCK)
-    set_nonblocking (true);
-  if (flags & SOCK_CLOEXEC)
-    set_close_on_exec (true);
-  set_io_handle ((HANDLE) sock);
   if (!init_events ())
     return -1;
+  if (flags & SOCK_NONBLOCK)
+    file_flags |= O_NONBLOCK;
+  if (flags & SOCK_CLOEXEC)
+    {
+      set_close_on_exec (true);
+      file_flags |= O_CLOEXEC;
+    }
+  set_flags (file_flags);
   if (lsp_fixup)
     init_fixup_before ();
-  set_flags (O_RDWR | O_BINARY);
   set_unique_id ();
   if (get_socket_type () == SOCK_DGRAM)
     {
diff --git a/winsup/cygwin/release/2.11.2 b/winsup/cygwin/release/2.11.2
index 2ae5fbc..24ec5e2 100644
--- a/winsup/cygwin/release/2.11.2
+++ b/winsup/cygwin/release/2.11.2
@@ -18,3 +18,7 @@ Bug Fixes
 - Fix potential memory corruption and SEGV if socket(2), socketpair(2),
   accept(2), or accept4(2) fail.
   Addresses: https://cygwin.com/ml/cygwin/2018-10/msg00229.html
+
+- Fix socket(2) and socketpair(2) calls mishandling SOCK_NONBLOCK and
+  SOCK_CLOEXEC flags.
+  Addresses: https://cygwin.com/ml/cygwin/2018-11/msg00017.html