linux-kernel - Re: [PATCH V2 07/10] Secure boot: Add a dummy kernel parameter that will switch on Secure Boot mode

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:	Thu, 20 Sep 2012 13:40:20 -0400
From:	Josh Boyer <jwboyer@...hat.com>
To:	Greg KH <gregkh@...uxfoundation.org>
Cc:	Matthew Garrett <mjg@...hat.com>, linux-kernel@...r.kernel.org,
	linux-security-module@...r.kernel.org, linux-efi@...r.kernel.org
Subject: Re: [PATCH V2 07/10] Secure boot: Add a dummy kernel parameter that
 will switch on Secure Boot mode

On Thu, Sep 20, 2012 at 05:32:37PM +0100, Greg KH wrote:
> On Thu, Sep 20, 2012 at 10:41:02AM -0400, Matthew Garrett wrote:
> > From: Josh Boyer <jwboyer@...hat.com>
> > 
> > This forcibly drops CAP_COMPROMISE_KERNEL from both cap_permitted and cap_bset
> > in the init_cred struct, which everything else inherits from.  This works on
> > any machine and can be used to develop even if the box doesn't have UEFI.
> > 
> > Signed-off-by: Josh Boyer <jwboyer@...hat.com>
> > ---
> >  kernel/cred.c | 17 +++++++++++++++++
> >  1 file changed, 17 insertions(+)
> > 
> > diff --git a/kernel/cred.c b/kernel/cred.c
> > index de728ac..7e6e83f 100644
> > --- a/kernel/cred.c
> > +++ b/kernel/cred.c
> > @@ -623,6 +623,23 @@ void __init cred_init(void)
> >  				     0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
> >  }
> >  
> > +void __init secureboot_enable()
> > +{
> > +	pr_info("Secure boot enabled\n");
> > +	cap_lower((&init_cred)->cap_bset, CAP_COMPROMISE_KERNEL);
> > +	cap_lower((&init_cred)->cap_permitted, CAP_COMPROMISE_KERNEL);
> > +}
> > +
> > +/* Dummy Secure Boot enable option to fake out UEFI SB=1 */
> > +static int __init secureboot_enable_opt(char *str)
> > +{
> > +	int sb_enable = !!simple_strtol(str, NULL, 0);
> > +	if (sb_enable)
> > +		secureboot_enable();
> > +	return 1;
> > +}
> > +__setup("secureboot_enable=", secureboot_enable_opt);
> 
> Document this please in the bootparams file.

Oops, yes.  Will do.  Thanks for pointing it out.

josh
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/