From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1034465AbeE1Pcm (ORCPT ); Mon, 28 May 2018 11:32:42 -0400 Received: from mx2.suse.de ([195.135.220.15]:35821 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1032956AbeE1PcS (ORCPT ); Mon, 28 May 2018 11:32:18 -0400 Date: Mon, 28 May 2018 11:30:55 +0200 Message-ID: From: Takashi Iwai To: "Takashi Sakamoto" Cc: , "Colin King" , "Oleksandr Andrushchenko" , , "Jaroslav Kysela" , , Subject: Re: [PATCH][next] ALSA: xen-front: fix unsigned error check on return from to_sndif_format In-Reply-To: References: <20180527213219.24182-1-colin.king@canonical.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 28 May 2018 00:49:03 +0200, Takashi Sakamoto wrote: > > Hi, > > On May 28 2018 06:32, Colin King wrote: > > From: Colin Ian King > > > > The negative error return from the call to to_sndif_format is being > > assigned to an unsigned 8 bit integer and hence the check for a negative > > value is always going to be false. Fix this by using ret as the error > > return and hence the negative error can be detected and assign > > the u8 sndif_format to ret if there is no error. > > > > Detected by CoverityScan, CID#1469385 ("Unsigned compared against 0") > > > > Signed-off-by: Colin Ian King > > --- > > sound/xen/xen_snd_front_alsa.c | 7 ++++--- > > 1 file changed, 4 insertions(+), 3 deletions(-) > > > > diff --git a/sound/xen/xen_snd_front_alsa.c b/sound/xen/xen_snd_front_alsa.c > > index 5041f83e98d2..5a2bd70a2fa1 100644 > > --- a/sound/xen/xen_snd_front_alsa.c > > +++ b/sound/xen/xen_snd_front_alsa.c > > @@ -466,13 +466,14 @@ static int alsa_prepare(struct snd_pcm_substream *substream) > > u8 sndif_format; > > int ret; > > - sndif_format = to_sndif_format(runtime->format); > > - if (sndif_format < 0) { > > + ret = to_sndif_format(runtime->format); > > + if (ret < 0) { > > dev_err(&stream->front_info->xb_dev->dev, > > "Unsupported sample format: %d\n", > > runtime->format); > > - return sndif_format; > > + return ret; > > } > > + sndif_format = ret; > > ret = > > xen_snd_front_stream_prepare(&stream->evt_pair->req, > > &stream->sh_buf, > > Indeed. A typical assignment mistake. Instead, we could change the > type of 'sndif_format' to signed int, however in this case it's not > the same as the third argument of xen_snd_front_stream_prepare() > because it is 'u8'. This patch looks good to me. > > Reviewed-by: Takashi Sakamoto Applied, thanks. Takashi