Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Sat, 12 Sep 2020 10:28:52 +1000 (AEST)
From: James Morris <>
To: Matthew Wilcox <>
cc: Mickaël Salaün <>,
        Mimi Zohar <>,,
        Aleksa Sarai <>, Alexei Starovoitov <>,
        Al Viro <>,
        Andrew Morton <>,
        Andy Lutomirski <>, Arnd Bergmann <>,
        Casey Schaufler <>,
        Christian Brauner <>,
        Christian Heimes <>,
        Daniel Borkmann <>,
        Deven Bowers <>,
        Dmitry Vyukov <>, Eric Biggers <>,
        Eric Chiang <>,
        Florian Weimer <>, Jan Kara <>,
        Jann Horn <>, Jonathan Corbet <>,
        Kees Cook <>,
        Lakshmi Ramasubramanian <>,
        Matthew Garrett <>,
        Michael Kerrisk <>,
        Miklos Szeredi <>,
        Philippe Trébuchet <>,
        Scott Shell <>,
        Sean Christopherson <>,
        Shuah Khan <>, Steve Dower <>,
        Steve Grubb <>,
        Tetsuo Handa <>,
        Thibaut Sautereau <>,
        Vincent Strubel <>,,,,,
Subject: Re: [RFC PATCH v9 0/3] Add introspect_access(2) (was O_MAYEXEC)

On Thu, 10 Sep 2020, Matthew Wilcox wrote:

> On Thu, Sep 10, 2020 at 08:38:21PM +0200, Mickaël Salaün wrote:
> > There is also the use case of noexec mounts and file permissions. From
> > user space point of view, it doesn't matter which kernel component is in
> > charge of defining the policy. The syscall should then not be tied with
> > a verification/integrity/signature/appraisal vocabulary, but simply an
> > access control one.
> permission()?

The caller is not asking the kernel to grant permission, it's asking 
"SHOULD I access this file?"

The caller doesn't know, for example, if the script file it's about to 
execute has been signed, or if it's from a noexec mount. It's asking the 
kernel, which does know. (Note that this could also be extended to reading 
configuration files).

How about: should_faccessat ?

James Morris

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.