linux-kernel - Re: [Linux-kernel-mentees] [PATCH v2 2/3] PCI: sysfs: Change permissions from symbolic to octal

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: <20190904062229.GA66871@JATN>
Date:   Wed, 4 Sep 2019 00:22:29 -0600
From:   Kelsey Skunberg <skunberg.kelsey@...il.com>
To:     Don Dutile <ddutile@...hat.com>
Cc:     Bjorn Helgaas <helgaas@...nel.org>, linux-pci@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        linux-kernel-mentees@...ts.linuxfoundation.org,
        Bodong Wang <bodong@...lanox.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: Re: [Linux-kernel-mentees] [PATCH v2 2/3] PCI: sysfs: Change
 permissions from symbolic to octal

On Thu, Aug 15, 2019 at 10:37:13AM -0400, Don Dutile wrote:
> On 08/14/2019 01:38 AM, Bjorn Helgaas wrote:
> > [+cc Bodong, Don, Greg for permission question]
> > 
> > On Tue, Aug 13, 2019 at 02:45:12PM -0600, Kelsey Skunberg wrote:
> > > Symbolic permissions such as "(S_IWUSR | S_IWGRP)" are not
> > > preferred and octal permissions should be used instead. Change all
> > > symbolic permissions to octal permissions.
> > > 
> > > Example of old:
> > > 
> > > "(S_IWUSR | S_IWGRP)"
> > > 
> > > Example of new:
> > > 
> > > "0220"
> > 
> > 
> > >   static DEVICE_ATTR_RO(sriov_totalvfs);
> > > -static DEVICE_ATTR(sriov_numvfs, (S_IRUGO | S_IWUSR | S_IWGRP),
> > > -				  sriov_numvfs_show, sriov_numvfs_store);
> > > +static DEVICE_ATTR(sriov_numvfs, 0664, sriov_numvfs_show, sriov_numvfs_store);
> > >   static DEVICE_ATTR_RO(sriov_offset);
> > >   static DEVICE_ATTR_RO(sriov_stride);
> > >   static DEVICE_ATTR_RO(sriov_vf_device);
> > > -static DEVICE_ATTR(sriov_drivers_autoprobe, (S_IRUGO | S_IWUSR | S_IWGRP),
> > > -		   sriov_drivers_autoprobe_show, sriov_drivers_autoprobe_store);
> > > +static DEVICE_ATTR(sriov_drivers_autoprobe, 0664, sriov_drivers_autoprobe_show,
> > > +		   sriov_drivers_autoprobe_store);
> > 
> > Greg noticed that sriov_numvfs and sriov_drivers_autoprobe have
> > "unusual" permissions.  These were added by:
> > 
> >    0e7df22401a3 ("PCI: Add sysfs sriov_drivers_autoprobe to control VF driver binding")
> >    1789382a72a5 ("PCI: SRIOV control and status via sysfs")
> > 
> > Kelsey's patch correctly preserves the existing permissions, but we
> > should double-check that they are the permissions they want, and
> > possibly add a comment about why they're different from the rest.
> > 
> > Bjorn
> > 

Hi Don,

> The rest being? ... 0644 vs 0664 ?
> The file is read & written, thus the (first) 6; I'll have to dig through very old (7 yr) notes to see if the second 6 is needed for libvirt (so it doesn't have to be root to enable).
> 
> -dd
>

Were you able to see if the unusual permissions (0664) are needed for
libvirt? I appreciate your help!

-Kelsey