From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pierre-Louis Bossart Subject: Re: [PATCH] SoC: cht_bsw_rt5645: Fix writing to string literal Date: Thu, 18 Feb 2016 00:02:23 -0800 Message-ID: <56C57A8F.9030306@linux.intel.com> References: <1455572189-11724-1-git-send-email-carlo@caione.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by alsa0.perex.cz (Postfix) with ESMTP id EFDC62607E8 for ; Thu, 18 Feb 2016 09:02:32 +0100 (CET) In-Reply-To: <1455572189-11724-1-git-send-email-carlo@caione.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Carlo Caione , lgirdwood@gmail.com, broonie@kernel.org, vinod.koul@intel.com, yang.a.fang@intel.com, linux@endlessm.com, alsa-devel@alsa-project.org Cc: Carlo Caione List-Id: alsa-devel@alsa-project.org On 2/15/16 1:36 PM, Carlo Caione wrote: > From: Carlo Caione > > We cannot use strcpy() to write to a const char * location. This is > causing a 'BUG: unable to handle kernel paging request' error at boot > when using the cht-bsw-rt5645 driver. > > With this patch we also fix a wrong indexing in the driver where the > codec_name of the wrong dai_link is being overwritten. > > Signed-off-by: Carlo Caione > --- > sound/soc/intel/atom/sst-atom-controls.h | 1 + > sound/soc/intel/boards/cht_bsw_rt5645.c | 4 ++-- > 2 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/sound/soc/intel/atom/sst-atom-controls.h b/sound/soc/intel/atom/sst-atom-controls.h > index e011311..6f88d1c 100644 > --- a/sound/soc/intel/atom/sst-atom-controls.h > +++ b/sound/soc/intel/atom/sst-atom-controls.h > @@ -30,6 +30,7 @@ enum { > MERR_DPCM_AUDIO = 0, > MERR_DPCM_DEEP_BUFFER, > MERR_DPCM_COMPR, > + MERR_DPCM_BE, > }; > > /* define a bit for each mixer input */ > diff --git a/sound/soc/intel/boards/cht_bsw_rt5645.c b/sound/soc/intel/boards/cht_bsw_rt5645.c > index e6cf800..89b4c032 100644 > --- a/sound/soc/intel/boards/cht_bsw_rt5645.c > +++ b/sound/soc/intel/boards/cht_bsw_rt5645.c > @@ -282,7 +282,7 @@ static struct snd_soc_dai_link cht_dailink[] = { > }, > /* CODEC<->CODEC link */ > /* back ends */ > - { > + [MERR_DPCM_BE] = { > .name = "SSP2-Codec", > .be_id = 1, > .cpu_dai_name = "ssp2-port", > @@ -357,7 +357,7 @@ static int snd_cht_mc_probe(struct platform_device *pdev) > card->dev = &pdev->dev; > sprintf(codec_name, "i2c-%s:00", drv->acpi_card->codec_id); > /* set correct codec name */ > - strcpy((char *)card->dai_link[2].codec_name, codec_name); > + card->dai_link[MERR_DPCM_BE].codec_name = kstrdup(codec_name, GFP_KERNEL); It's probably less problematic to find the index in a different way. Adding a new definition in the platform driver doesn't seem quite right.