From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43323) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dcpz5-0002qm-8x for qemu-devel@nongnu.org; Wed, 02 Aug 2017 05:30:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dcpz1-0000ry-9d for qemu-devel@nongnu.org; Wed, 02 Aug 2017 05:30:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44428) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dcpz1-0000rM-3C for qemu-devel@nongnu.org; Wed, 02 Aug 2017 05:30:27 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1CA2D3680F for ; Wed, 2 Aug 2017 09:30:26 +0000 (UTC) Date: Wed, 2 Aug 2017 10:30:20 +0100 From: "Daniel P. Berrange" Message-ID: <20170802093020.GD4098@redhat.com> Reply-To: "Daniel P. Berrange" References: <1501644321-17721-1-git-send-email-peterx@redhat.com> <1501644321-17721-3-git-send-email-peterx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1501644321-17721-3-git-send-email-peterx@redhat.com> Subject: Re: [Qemu-devel] [PATCH 2/2] io: fix qio_channel_socket_accept err handling List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Xu Cc: qemu-devel@nongnu.org, Laurent Vivier , Juan Quintela , "Dr . David Alan Gilbert" On Wed, Aug 02, 2017 at 11:25:21AM +0800, Peter Xu wrote: > When accept failed, we should setup errp with the reason. More > importantly, the caller may assume errp be non-NULL when error happens, > and not setting the errp may crash QEMU. > > At the same time, move the trace_qio_channel_socket_accept_fail() after > the if check on EINTR. Two reasons: > > 1. when EINTR happened, it's not really a fault (we should just try > again), so we should not log with an "accept failure". > > 2. trace_*() functions may overwrite errno, then the old errno will be > missing. We need to either check errno before trace_*() calls, or > reserve the errno. > > Signed-off-by: Peter Xu > --- > io/channel-socket.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/io/channel-socket.c b/io/channel-socket.c > index 53386b7..442f230 100644 > --- a/io/channel-socket.c > +++ b/io/channel-socket.c > @@ -340,10 +340,11 @@ qio_channel_socket_accept(QIOChannelSocket *ioc, > cioc->fd = qemu_accept(ioc->fd, (struct sockaddr *)&cioc->remoteAddr, > &cioc->remoteAddrLen); > if (cioc->fd < 0) { > - trace_qio_channel_socket_accept_fail(ioc); > if (errno == EINTR) { > goto retry; > } > + trace_qio_channel_socket_accept_fail(ioc); > + error_setg_errno(errp, errno, "Unable to accept connection"); Err, you're still clobbering errno in trace_qio_channel_socket_accept_fail before calling error_setg_errno Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|