linux-kernel - Re: [PATCH][drm-next] drm/i915/gvt: ensure -ve return value is handled correctly

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20170920224406.jscthkglwfy3xhtf@zhen-hp.sh.intel.com>
Date:   Thu, 21 Sep 2017 06:44:06 +0800
From:   Zhenyu Wang <zhenyuw@...ux.intel.com>
To:     Joe Perches <joe@...ches.com>
Cc:     Colin King <colin.king@...onical.com>,
        fred gao <fred.gao@...el.com>, Zhi Wang <zhi.a.wang@...el.com>,
        Jani Nikula <jani.nikula@...ux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@...el.com>,
        David Airlie <airlied@...ux.ie>,
        intel-gvt-dev@...ts.freedesktop.org,
        intel-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
        kernel-janitors@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH][drm-next] drm/i915/gvt: ensure -ve return value is
 handled correctly

On 2017.09.19 19:35:23 -0700, Joe Perches wrote:
> On Wed, 2017-09-20 at 05:46 +0800, Zhenyu Wang wrote:
> > On 2017.09.19 16:55:34 +0100, Colin King wrote:
> > > From: Colin Ian King <colin.king@...onical.com>
> > > 
> > > An earlier fix changed the return type from find_bb_size however the
> > > integer return is being assigned to a unsigned int so the -ve error
> > > check will never be detected. Make bb_size an int to fix this.
> > > 
> > > Detected by CoverityScan CID#1456886 ("Unsigned compared against 0")
> > > 
> > > Fixes: 1e3197d6ad73 ("drm/i915/gvt: Refine error handling for perform_bb_shadow")
> > > Signed-off-by: Colin Ian King <colin.king@...onical.com>
> > > ---
> > >  drivers/gpu/drm/i915/gvt/cmd_parser.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/gvt/cmd_parser.c b/drivers/gpu/drm/i915/gvt/cmd_parser.c
> > > index 2c0ccbb817dc..f41cbf664b69 100644
> > > --- a/drivers/gpu/drm/i915/gvt/cmd_parser.c
> > > +++ b/drivers/gpu/drm/i915/gvt/cmd_parser.c
> > > @@ -1628,7 +1628,7 @@ static int perform_bb_shadow(struct parser_exec_state *s)
> > >  	struct intel_shadow_bb_entry *entry_obj;
> > >  	struct intel_vgpu *vgpu = s->vgpu;
> > >  	unsigned long gma = 0;
> > > -	uint32_t bb_size;
> > > +	int bb_size;
> > >  	void *dst = NULL;
> > >  	int ret = 0;
> > >  
> > 
> > Applied this, thanks!
> 
> Is it possible for bb_size to be both >= 2g and valid?

Never be possible in practise and if really that big I think something
is already insane indeed.

-- 
Open Source Technology Center, Intel ltd.

$gpg --keyserver wwwkeys.pgp.net --recv-keys 4D781827

Download attachment "signature.asc" of type "application/pgp-signature" (196 bytes)