| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20161121073639.pjikxfytzms6b6yk@lukather>
Date: Mon, 21 Nov 2016 08:36:39 +0100
From: Maxime Ripard <maxime.ripard@...e-electrons.com>
To: Sean Paul <seanpaul@...omium.org>
Cc: Daniel Vetter <daniel.vetter@...el.com>,
David Airlie <airlied@...ux.ie>,
dri-devel <dri-devel@...ts.freedesktop.org>,
Laurent Pinchart <laurent.pinchart@...asonboard.com>,
Boris Brezillon <boris.brezillon@...e-electrons.com>,
Thomas Petazzoni <thomas.petazzoni@...e-electrons.com>,
Linux ARM Kernel <linux-arm-kernel@...ts.infradead.org>,
Hans de Goede <hdegoede@...hat.com>,
Chen-Yu Tsai <wens@...e.org>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 1/5] drm/modes: Rewrite the command line parser
Hi Sean,
Thanks for taking the time to review this.
On Wed, Nov 16, 2016 at 12:12:53PM -0500, Sean Paul wrote:
> On Tue, Oct 18, 2016 at 4:29 AM, Maxime Ripard
> <maxime.ripard@...e-electrons.com> wrote:
> > Rewrite the command line parser in order to get away from the state machine
> > parsing the video mode lines.
> >
> > Hopefully, this will allow to extend it more easily to support named modes
> > and / or properties set directly on the command line.
> >
> > Signed-off-by: Maxime Ripard <maxime.ripard@...e-electrons.com>
> > ---
> > drivers/gpu/drm/drm_modes.c | 305 +++++++++++++++++++++++--------------
> > 1 file changed, 190 insertions(+), 115 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
> > index 53f07ac7c174..7d5bdca276f2 100644
> > --- a/drivers/gpu/drm/drm_modes.c
> > +++ b/drivers/gpu/drm/drm_modes.c
> > @@ -30,6 +30,7 @@
> > * authorization from the copyright holder(s) and author(s).
> > */
> >
> > +#include <linux/ctype.h>
> > #include <linux/list.h>
> > #include <linux/list_sort.h>
> > #include <linux/export.h>
> > @@ -1261,6 +1262,131 @@ void drm_mode_connector_list_update(struct drm_connector *connector)
> > }
> > EXPORT_SYMBOL(drm_mode_connector_list_update);
> >
> > +static int drm_mode_parse_cmdline_bpp(const char *str, char **end_ptr,
> > + struct drm_cmdline_mode *mode)
> > +{
> > + if (str[0] != '-')
> > + return -EINVAL;
> > +
> > + mode->bpp = simple_strtol(str + 1, end_ptr, 10);
> > + mode->bpp_specified = true;
> > +
> > + return 0;
> > +}
> > +
> > +static int drm_mode_parse_cmdline_refresh(const char *str, char **end_ptr,
> > + struct drm_cmdline_mode *mode)
> > +{
> > + if (str[0] != '@')
> > + return -EINVAL;
> > +
> > + mode->refresh = simple_strtol(str + 1, end_ptr, 10);
> > + mode->refresh_specified = true;
> > +
> > + return 0;
> > +}
> > +
> > +static int drm_mode_parse_cmdline_extra(const char *str, int length,
> > + struct drm_connector *connector,
> > + struct drm_cmdline_mode *mode)
> > +{
> > + int i;
> > +
> > + for (i = 0; i < length; i++) {
> > + switch (str[i]) {
> > + case 'i':
> > + mode->interlace = true;
> > + break;
> > + case 'm':
> > + mode->margins = true;
> > + break;
> > + case 'D':
> > + if (mode->force != DRM_FORCE_UNSPECIFIED)
> > + return -EINVAL;
> > +
> > + if ((connector->connector_type != DRM_MODE_CONNECTOR_DVII) &&
> > + (connector->connector_type != DRM_MODE_CONNECTOR_HDMIB))
> > + mode->force = DRM_FORCE_ON;
> > + else
> > + mode->force = DRM_FORCE_ON_DIGITAL;
> > + break;
> > + case 'd':
> > + if (mode->force != DRM_FORCE_UNSPECIFIED)
> > + return -EINVAL;
> > +
> > + mode->force = DRM_FORCE_OFF;
> > + break;
> > + case 'e':
> > + if (mode->force != DRM_FORCE_UNSPECIFIED)
> > + return -EINVAL;
> > +
> > + mode->force = DRM_FORCE_ON;
> > + break;
> > + default:
> > + return -EINVAL;
> > + }
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int drm_mode_parse_cmdline_res_mode(const char *str, unsigned int length,
> > + bool extras,
> > + struct drm_connector *connector,
> > + struct drm_cmdline_mode *mode)
> > +{
> > + bool rb = false, cvt = false;
> > + int xres = 0, yres = 0;
> > + int remaining, i;
> > + char *end_ptr;
> > +
> > + xres = simple_strtol(str, &end_ptr, 10);
> > +
>
> checkpatch is telling me to use kstrtol instead, as simple_strtol is deprecated
>
> > + if (end_ptr[0] != 'x')
>
> check that end_ptr != NULL? you should probably also check that xres
> isn't an error (ie: -ERANGE or -EINVAL)
>
> > + return -EINVAL;
> > + end_ptr++;
> > +
> > + yres = simple_strtol(end_ptr, &end_ptr, 10);
>
> check end_ptr != NULL and yres sane
>
> > +
> > + remaining = length - (end_ptr - str);
> > + if (remaining < 0)
>
> right, so if end_ptr is NULL here, we'll end up with a huge positive
> value for remaining :)
>
> > + return -EINVAL;
> > +
> > + for (i = 0; i < remaining; i++) {
> > + switch (end_ptr[i]) {
> > + case 'M':
> > + cvt = true;
>
> the previous code ensured proper ordering as well as parsing, whereas
> yours will take these in any order (and accepts duplicates). i don't
> think this should cause any issues, but perhaps something to verify.
Yes, I definitely overlooked the order of the parameters (and now I
get why the switch was so convoluted...)
I'll come up with a second version fixing that (and the other comments
you had).
Maxime
--
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
Download attachment "signature.asc" of type "application/pgp-signature" (802 bytes)
Powered by blists - more mailing lists