From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52159) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fadxR-0000mn-S4 for qemu-devel@nongnu.org; Wed, 04 Jul 2018 05:20:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fadxO-0005MV-Q1 for qemu-devel@nongnu.org; Wed, 04 Jul 2018 05:20:17 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:35246 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fadxO-0005M6-LR for qemu-devel@nongnu.org; Wed, 04 Jul 2018 05:20:14 -0400 Date: Wed, 4 Jul 2018 10:20:07 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Message-ID: <20180704092007.GA32267@redhat.com> Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= References: <20180704033642.15996-1-caoxinhua@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180704033642.15996-1-caoxinhua@huawei.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH] qemu-char: check errno together with ret < 0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "xinhua.Cao" Cc: pbonzini@redhat.com, marcandre.lureau@redhat.com, eblake@redhat.com, anton.nefedov@virtuozzo.com, vsementsov@virtuozzo.com, weidong.huang@huawei.com, weifuqiang@huawei.com, qemu-devel@nongnu.org, king.wang@huawei.com, liuyongan@huawei.com, arei.gonglei@huawei.com On Wed, Jul 04, 2018 at 11:36:42AM +0800, xinhua.Cao wrote: > In the tcp_chr_write function, we checked errno, > but errno was not reset before a read or write operation. > Therefore, this check of errno's actions is often > incorrect after EAGAIN has occurred. > we need check errno together with ret < 0. >=20 > Signed-off-by: xinhua.Cao > --- > chardev/char-socket.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) >=20 > diff --git a/chardev/char-socket.c b/chardev/char-socket.c > index 17519ec..efbad6e 100644 > --- a/chardev/char-socket.c > +++ b/chardev/char-socket.c > @@ -134,8 +134,11 @@ static int tcp_chr_write(Chardev *chr, const uint8= _t *buf, int len) > s->write_msgfds, > s->write_msgfds_num); > =20 > - /* free the written msgfds in any cases other than errno=3D=3D= EAGAIN */ > - if (EAGAIN !=3D errno && s->write_msgfds_num) { > + /* free the written msgfds in any cases > + * other than ret < 0 && errno =3D=3D EAGAIN > + */ > + if (!(ret < 0 && EAGAIN =3D=3D errno) > + && s->write_msgfds_num) { > g_free(s->write_msgfds); > s->write_msgfds =3D 0; > s->write_msgfds_num =3D 0; Reviewed-by: Daniel P. Berrang=C3=A9 Regards, Daniel --=20 |: https://berrange.com -o- https://www.flickr.com/photos/dberran= ge :| |: https://libvirt.org -o- https://fstop138.berrange.c= om :| |: https://entangle-photo.org -o- https://www.instagram.com/dberran= ge :|