[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 <***@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 <***@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