[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Thu, 14 May 2020 10:12:34 +0000
From: David Laight <David.Laight@...LAB.COM>
To: 'Kees Cook' <keescook@...omium.org>, Stephen Smalley
<stephen.smalley.work@...il.com>
CC: Mickaël Salaün <mic@...ikod.net>, linux-kernel
<linux-kernel@...r.kernel.org>, Aleksa Sarai <cyphar@...har.com>, "Alexei
Starovoitov" <ast@...nel.org>, Al Viro <viro@...iv.linux.org.uk>, "Andy
Lutomirski" <luto@...nel.org>, Christian Heimes <christian@...hon.org>,
"Daniel Borkmann" <daniel@...earbox.net>, Deven Bowers
<deven.desai@...ux.microsoft.com>, Eric Chiang <ericchiang@...gle.com>,
Florian Weimer <fweimer@...hat.com>, James Morris <jmorris@...ei.org>, "Jan
Kara" <jack@...e.cz>, Jann Horn <jannh@...gle.com>, Jonathan Corbet
<corbet@....net>, Lakshmi Ramasubramanian <nramas@...ux.microsoft.com>,
Matthew Garrett <mjg59@...gle.com>, Matthew Wilcox <willy@...radead.org>,
Michael Kerrisk <mtk.manpages@...il.com>, Mickaël Salaün
<mickael.salaun@....gouv.fr>, Mimi Zohar <zohar@...ux.ibm.com>,
Philippe Trébuchet <philippe.trebuchet@....gouv.fr>,
"Scott Shell" <scottsh@...rosoft.com>, Sean Christopherson
<sean.j.christopherson@...el.com>, Shuah Khan <shuah@...nel.org>, Steve Dower
<steve.dower@...hon.org>, Steve Grubb <sgrubb@...hat.com>, Thibaut Sautereau
<thibaut.sautereau@....gouv.fr>, Vincent Strubel
<vincent.strubel@....gouv.fr>, "kernel-hardening@...ts.openwall.com"
<kernel-hardening@...ts.openwall.com>, "linux-api@...r.kernel.org"
<linux-api@...r.kernel.org>, "linux-integrity@...r.kernel.org"
<linux-integrity@...r.kernel.org>, LSM List
<linux-security-module@...r.kernel.org>, Linux FS Devel
<linux-fsdevel@...r.kernel.org>
Subject: RE: [PATCH v5 3/6] fs: Enable to enforce noexec mounts or file exec
through O_MAYEXEC
From: Kees Cook
> Sent: 14 May 2020 04:05
> On Wed, May 13, 2020 at 04:27:39PM -0700, Kees Cook wrote:
> > Like, couldn't just the entire thing just be:
> >
> > diff --git a/fs/namei.c b/fs/namei.c
> > index a320371899cf..0ab18e19f5da 100644
> > --- a/fs/namei.c
> > +++ b/fs/namei.c
> > @@ -2849,6 +2849,13 @@ static int may_open(const struct path *path, int acc_mode, int flag)
> > break;
> > }
> >
> > + if (unlikely(mask & MAY_OPENEXEC)) {
> > + if (sysctl_omayexec_enforce & OMAYEXEC_ENFORCE_MOUNT &&
> > + path_noexec(path))
> > + return -EACCES;
> > + if (sysctl_omayexec_enforce & OMAYEXEC_ENFORCE_FILE)
> > + acc_mode |= MAY_EXEC;
> > + }
> > error = inode_permission(inode, MAY_OPEN | acc_mode);
> > if (error)
> > return error;
> >
>
> FYI, I've confirmed this now. Effectively with patch 2 dropped, patch 3
> reduced to this plus the Kconfig and sysctl changes, the self tests
> pass.
>
> I think this makes things much cleaner and correct.
And a summary of that would be right for the 0/n patch email.
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
