Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751961AbbLHX2b (ORCPT ); Tue, 8 Dec 2015 18:28:31 -0500 Received: from mail-ig0-f169.google.com ([209.85.213.169]:38170 "EHLO mail-ig0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751132AbbLHX21 (ORCPT ); Tue, 8 Dec 2015 18:28:27 -0500 MIME-Version: 1.0 In-Reply-To: <1449612732-32438-1-git-send-email-nicolas.iooss_linux@m4x.org> References: <1449612732-32438-1-git-send-email-nicolas.iooss_linux@m4x.org> Date: Tue, 8 Dec 2015 23:28:27 +0000 Message-ID: Subject: Re: [PATCH 1/2] drm: make drm_dev_set_unique() not use a format string From: Emil Velikov To: Nicolas Iooss Cc: Boris Brezillon , David Airlie , Jianwei Wang , Alison Wang , Mark Yao , Thierry Reding , =?UTF-8?Q?Terje_Bergstr=C3=B6m?= , Stephen Warren , ML dri-devel , linux-tegra@vger.kernel.org, "Linux-Kernel@Vger. Kernel. Org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2166 Lines: 46 On 8 December 2015 at 22:12, Nicolas Iooss wrote: > drm_dev_set_unique() uses a format string to define the unique name of a > device. This feature is not used as currently all the calls to this > function either use "%s" as a format string or directly use > dev_name(). > > Even though this second kind of call does not introduce security > problems, because there cannot be "%" characters in dev_name() results, > gcc issues a warning when building with -Wformat-security flag > ("warning: format string is not a string literal (potentially > insecure)"). This warning is useful to find real bugs like the one > fixed by commit 3958b79266b1 ("configfs: fix kernel infoleak through > user-controlled format string"). False positives which do not bring > an extra value make the work of finding real bugs harder. > > Therefore remove the format-string feature from drm_dev_set_unique(). > > Signed-off-by: Nicolas Iooss > --- > drivers/gpu/drm/drm_drv.c | 11 +++-------- > drivers/gpu/drm/nouveau/nouveau_drm.c | 2 +- > drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 2 +- > include/drm/drmP.h | 2 +- > 4 files changed, 6 insertions(+), 11 deletions(-) > > diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c > index 7dd6728dd092..20eaa0aae205 100644 > --- a/drivers/gpu/drm/drm_drv.c > +++ b/drivers/gpu/drm/drm_drv.c > @@ -797,7 +797,7 @@ EXPORT_SYMBOL(drm_dev_unregister); > /** > * drm_dev_set_unique - Set the unique name of a DRM device > * @dev: device of which to set the unique name > - * @fmt: format string for unique name > + * @name: unique name > * > * Sets the unique name of a DRM device using the specified format string and > * a variable list of arguments. Drivers can use this at driver probe time if You might want to also update the above hunk :-) -Emil -- 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/