From mboxrd@z Thu Jan 1 00:00:00 1970 From: Qian Cai Subject: Re: [PATCH] gpu/drm: fix a -Wstringop-truncation warning Date: Thu, 05 Sep 2019 10:40:59 -0400 Message-ID: <1567694459.5576.94.camel@lca.pw> References: <1566585426-2952-1-git-send-email-cai@lca.pw> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <1566585426-2952-1-git-send-email-cai@lca.pw> Sender: linux-kernel-owner@vger.kernel.org To: daniel@ffwll.ch Cc: maarten.lankhorst@linux.intel.com, maxime.ripard@bootlin.com, sean@poorly.run, airlied@linux.ie, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org List-Id: dri-devel@lists.freedesktop.org Ping. Please take a look at this trivial patch. On Fri, 2019-08-23 at 14:37 -0400, Qian Cai wrote: > In file included from ./include/linux/bitmap.h:9, >                  from ./include/linux/cpumask.h:12, >                  from ./arch/x86/include/asm/cpumask.h:5, >                  from ./arch/x86/include/asm/msr.h:11, >                  from ./arch/x86/include/asm/processor.h:21, >                  from ./arch/x86/include/asm/cpufeature.h:5, >                  from ./arch/x86/include/asm/thread_info.h:53, >                  from ./include/linux/thread_info.h:38, >                  from ./arch/x86/include/asm/preempt.h:7, >                  from ./include/linux/preempt.h:78, >                  from ./include/linux/rcupdate.h:27, >                  from ./include/linux/rculist.h:11, >                  from ./include/linux/pid.h:5, >                  from ./include/linux/sched.h:14, >                  from ./include/linux/uaccess.h:5, >                  from drivers/gpu/drm/drm_property.c:24: > In function 'strncpy', >     inlined from 'drm_property_create' at > drivers/gpu/drm/drm_property.c:130:2: > ./include/linux/string.h:305:9: warning: '__builtin_strncpy' specified > bound 32 equals destination size [-Wstringop-truncation] >   return __builtin_strncpy(p, q, size); >          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Fix it by using strscpy() which will always return a valid string, and > doesn't unnecessarily force the tail of the destination buffer to be > zeroed. > > Signed-off-by: Qian Cai > --- >  drivers/gpu/drm/drm_property.c | 3 +-- >  1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/drm_property.c b/drivers/gpu/drm/drm_property.c > index 892ce636ef72..66ec2cc7a559 100644 > --- a/drivers/gpu/drm/drm_property.c > +++ b/drivers/gpu/drm/drm_property.c > @@ -127,8 +127,7 @@ struct drm_property *drm_property_create(struct drm_device > *dev, >   property->num_values = num_values; >   INIT_LIST_HEAD(&property->enum_list); >   > - strncpy(property->name, name, DRM_PROP_NAME_LEN); > - property->name[DRM_PROP_NAME_LEN-1] = '\0'; > + strscpy(property->name, name, DRM_PROP_NAME_LEN); >   >   list_add_tail(&property->head, &dev->mode_config.property_list); >