Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751581AbaG3IKe (ORCPT ); Wed, 30 Jul 2014 04:10:34 -0400 Received: from e06smtp11.uk.ibm.com ([195.75.94.107]:40186 "EHLO e06smtp11.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751031AbaG3IKa (ORCPT ); Wed, 30 Jul 2014 04:10:30 -0400 Message-ID: <1406707812.22788.3.camel@BR9GV9YG.de.ibm.com> Subject: Re: [PATCH] s390: net: claw.c: Fix a define larger than in a sizeof in conjunction with strncpy From: Ursula Braun To: Rickard Strandqvist Cc: Ursula Braun , Frank Blaschka , linux390@de.ibm.com, Martin Schwidefsky , Heiko Carstens , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org Date: Wed, 30 Jul 2014 10:10:12 +0200 In-Reply-To: <1406461822-11249-2-git-send-email-rickard_strandqvist@spectrumdigital.se> References: <1406461822-11249-1-git-send-email-rickard_strandqvist@spectrumdigital.se> <1406461822-11249-2-git-send-email-rickard_strandqvist@spectrumdigital.se> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14073008-5024-0000-0000-000000D6152D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2014-07-27 at 13:50 +0200, Rickard Strandqvist wrote: > The MAX_NAME_LEN is larger than sizeof, which could potentially > giving lots of error here. > > Signed-off-by: Rickard Strandqvist > --- > drivers/s390/net/claw.c | 31 +++++++++++++++++++------------ > 1 file changed, 19 insertions(+), 12 deletions(-) > > diff --git a/drivers/s390/net/claw.c b/drivers/s390/net/claw.c > index d837c3c..0172ce8 100644 > --- a/drivers/s390/net/claw.c > +++ b/drivers/s390/net/claw.c > @@ -3068,12 +3068,15 @@ claw_hname_write(struct device *dev, struct device_attribute *attr, > if (!priv) > return -ENODEV; > p_env = priv->p_env; > - if (count > MAX_NAME_LEN+1) > + if (count >= sizeof(p_env->host_name) && count > 0) > return -EINVAL; > - memset(p_env->host_name, 0x20, MAX_NAME_LEN); > + > strncpy(p_env->host_name,buf, count); > - p_env->host_name[count-1] = 0x20; /* clear extra 0x0a */ > - p_env->host_name[MAX_NAME_LEN] = 0x00; > + /* clear extra 0x0a */ > + memset(&p_env->host_name[count - 1], > + ' ', sizeof(p_env->host_name) - count); > + p_env->host_name[sizeof(p_env->host_name) - 1] = '\0'; > + > CLAW_DBF_TEXT(2, setup, "HstnSet"); > CLAW_DBF_TEXT_(2, setup, "%s", p_env->host_name); > > @@ -3106,12 +3109,14 @@ claw_adname_write(struct device *dev, struct device_attribute *attr, > if (!priv) > return -ENODEV; > p_env = priv->p_env; > - if (count > MAX_NAME_LEN+1) > + if (count >= sizeof(p_env->adapter_name) && count > 0) > return -EINVAL; > - memset(p_env->adapter_name, 0x20, MAX_NAME_LEN); > + > strncpy(p_env->adapter_name,buf, count); > - p_env->adapter_name[count-1] = 0x20; /* clear extra 0x0a */ > - p_env->adapter_name[MAX_NAME_LEN] = 0x00; > + /* clear extra 0x0a */ > + memset(&p_env->adapter_name[count - 1], > + ' ', sizeof(p_env->adapter_name) - count); > + p_env->adapter_name[sizeof(p_env->adapter_name) - 1] = '\0'; > CLAW_DBF_TEXT(2, setup, "AdnSet"); > CLAW_DBF_TEXT_(2, setup, "%s", p_env->adapter_name); > > @@ -3145,12 +3150,14 @@ claw_apname_write(struct device *dev, struct device_attribute *attr, > if (!priv) > return -ENODEV; > p_env = priv->p_env; > - if (count > MAX_NAME_LEN+1) > + if (count >= sizeof(p_env->api_type) && count > 0) > return -EINVAL; > - memset(p_env->api_type, 0x20, MAX_NAME_LEN); > + > strncpy(p_env->api_type,buf, count); > - p_env->api_type[count-1] = 0x20; /* we get a loose 0x0a */ > - p_env->api_type[MAX_NAME_LEN] = 0x00; > + /* we get a loose 0x0a */ > + memset(&p_env->api_type[count - 1], > + ' ', sizeof(p_env->api_type) - count); > + p_env->api_type[sizeof(p_env->api_type) - 1] = '\0'; > if(strncmp(p_env->api_type,WS_APPL_NAME_PACKED,6) == 0) { > p_env->read_size=DEF_PACK_BUFSIZE; > p_env->write_size=DEF_PACK_BUFSIZE; Why do you say "MAX_NAME_LEN is larger than sizeof"? MAX_NAME_LEN is 8, and claw_env has defined its char arrays as ...[9]? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/