Re: [Qemu-devel] [PATCH 0/3] slirp: deliver received TCP RSTs to the guest

[Thomas Huth <thuth@redhat.com>]

On 06.04.2016 02:13, steven@steven676.net wrote:
> QEMU's user-mode networking does not currently pass received TCP RSTs to
> guests, meaning that applications in guests hang if the remote server
> rejects their network connections.  This is particularly noticeable when
> IPv6 is enabled, the guest is configured to prefer IPv6 and the remote
> server rejects IPv6 connections (segment-data.zqtk.net is one example),
> but the bug appears to be longstanding and affects TCP over IPv4 as
> well.
> 
> There are three short patches in this series.  The first fixes a crash
> which would be exposed by the last patch in the series.  The second,
> which fixes delivery of an RST interrupting an already-established TCP
> connection, was submitted by Edgar Iglesias in 2008 and appears to have
> been missed then.  The last patch fixes the case where the remote end
> sends RST in reply to our SYN (rejects our incoming connection attempt).
> 
> Lightly tested on a Linux host with Linux and Windows 7 guests.
> 
> Edgar E. Iglesias (1):
>   slirp: Propagate host TCP RST to the guest.
> 
> Steven Luo (2):
>   slirp: don't crash when tcp_sockclosed() is called with a NULL tp
>   slirp: handle deferred ECONNREFUSED on non-blocking TCP sockets
> 
>  slirp/socket.c    | 17 ++++++++++++++++-
>  slirp/tcp_input.c |  6 ++++++
>  slirp/tcp_subr.c  |  7 +++++--
>  3 files changed, 27 insertions(+), 3 deletions(-)

FWIW, please make sure to CC: Samuel Thibault when posting slirp patches
- he's the new (co-)maintainer of the slirp code now.

 Thanks,
  Thomas