linux-kernel - Re: [PATCH] Xen: ARM: Zero reserved fields of xatp before making hypervisor call

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]

Date:   Mon, 19 Dec 2016 10:49:32 -0800 (PST)
From:   Stefano Stabellini <sstabellini@...nel.org>
To:     Juergen Gross <jgross@...e.com>
cc:     Jiandi An <anjiandi@...eaurora.org>, boris.ostrovsky@...cle.com,
        xen-devel@...ts.xenproject.org, linux-kernel@...r.kernel.org,
        julien.grall@....com, sstabellini@...nel.org,
        shankerd@...eaurora.org, shannon.zhao@...aro.org
Subject: Re: [PATCH] Xen: ARM: Zero reserved fields of xatp before making
 hypervisor call

On Mon, 19 Dec 2016, Juergen Gross wrote:
> On 19/12/16 03:56, Jiandi An wrote:
> > Ensure all reserved fields of xatp are zero before making hypervisor
> > call to XEN in xen_map_device_mmio().  xenmem_add_to_physmap_one() in
> > XEN fails the mapping request if extra.res reserved field in xatp is
> > not zero for XENMAPSPACE_dev_mmio request.
> > 
> > Signed-off-by: Jiandi An <anjiandi@...eaurora.org>
> > ---
> >  drivers/xen/arm-device.c | 3 +++
> >  1 file changed, 3 insertions(+)
> > 
> > diff --git a/drivers/xen/arm-device.c b/drivers/xen/arm-device.c
> > index 778acf8..208273b 100644
> > --- a/drivers/xen/arm-device.c
> > +++ b/drivers/xen/arm-device.c
> > @@ -87,6 +87,9 @@ static int xen_map_device_mmio(const struct resource *resources,
> >  			idxs[j] = XEN_PFN_DOWN(r->start) + j;
> >  		}
> >  
> > +		/* Ensure reserved fields are set to zero */
> > +		memset(&xatp, 0, sizeof(xatp));
> > +
> >  		xatp.domid = DOMID_SELF;
> >  		xatp.size = nr;
> >  		xatp.space = XENMAPSPACE_dev_mmio;
> 
> Instead of setting xatp to 0 in each iteration I'd prefer a static
> initialization of .domid and .space:
> 
> 	struct xen_add_to_physmap_range xatp = {
> 		.domid = DOMID_SELF,
> 		.space = XENMAPSPACE_dev_mmio
> 	};

+1