From: Oleg Nesterov <oleg@redhat.com>
To: Tycho Andersen <tycho@tycho.ws>
Cc: Kees Cook <keescook@chromium.org>,
Andy Lutomirski <luto@amacapital.net>,
"Eric W . Biederman" <ebiederm@xmission.com>,
"Serge E . Hallyn" <serge@hallyn.com>,
Christian Brauner <christian@brauner.io>,
Tyler Hicks <tyhicks@canonical.com>,
Akihiro Suda <suda.akihiro@lab.ntt.co.jp>,
Aleksa Sarai <asarai@suse.de>,
linux-kernel@vger.kernel.org,
containers@lists.linux-foundation.org, linux-api@vger.kernel.org
Subject: Re: [PATCH v8 1/2] seccomp: add a return code to trap to userspace
Date: Fri, 30 Nov 2018 11:17:51 +0100 [thread overview]
Message-ID: <20181130101751.GA23670@redhat.com> (raw)
In-Reply-To: <20181129230826.GB4676@cisco>
On 11/29, Tycho Andersen wrote:
>
> /*
> * These should never be seen by user programs. To return one of ERESTART*
> * codes, signal_pending() MUST be set. Note that ptrace can observe these
> * at syscall exit tracing, but they will never be left for the debugged user
> * process to see.
> */
> #define ERESTARTSYS 512
>
> So basically, if you respond with -ERESTARTSYS with no signal pending, you'll
> leak it to userspace.
Yes,
> It turns out this is already possible with
> SECCOMP_RET_TRAP (and probably ptrace alone,
Yes,
> The question is: do we care?
I think we do not care, debugger can do anything with the tracee.
Oleg.
next prev parent reply other threads:[~2018-11-30 10:17 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-29 22:40 [PATCH v8 0/2] seccomp trap to userspace Tycho Andersen
2018-10-29 22:40 ` [PATCH v8 1/2] seccomp: add a return code to " Tycho Andersen
2018-10-30 14:32 ` Oleg Nesterov
2018-10-30 15:32 ` Tycho Andersen
2018-11-01 14:48 ` Oleg Nesterov
2018-11-01 20:33 ` Tycho Andersen
2018-11-02 11:29 ` Oleg Nesterov
2018-11-02 13:50 ` Tycho Andersen
2018-10-30 15:02 ` Oleg Nesterov
2018-10-30 15:54 ` Tycho Andersen
2018-10-30 15:54 ` Tycho Andersen
2018-10-30 16:27 ` Oleg Nesterov
2018-10-30 16:39 ` Oleg Nesterov
2018-10-30 17:21 ` Tycho Andersen
2018-10-30 21:32 ` Kees Cook
2018-10-31 13:04 ` Oleg Nesterov
2018-10-30 21:38 ` Kees Cook
2018-10-30 21:49 ` Kees Cook
2018-10-30 21:54 ` Tycho Andersen
2018-10-30 22:00 ` Kees Cook
2018-10-30 22:32 ` Tycho Andersen
2018-10-30 22:34 ` Kees Cook
2018-10-31 0:29 ` Tycho Andersen
2018-10-31 1:29 ` Kees Cook
2018-11-01 13:40 ` Oleg Nesterov
2018-11-01 19:56 ` Tycho Andersen
2018-11-02 10:02 ` Oleg Nesterov
2018-11-02 13:38 ` Tycho Andersen
2018-11-01 13:56 ` Oleg Nesterov
2018-11-01 19:58 ` Tycho Andersen
2018-11-29 23:08 ` Tycho Andersen
2018-11-30 10:17 ` Oleg Nesterov [this message]
2018-10-29 22:40 ` [PATCH v8 2/2] samples: add an example of seccomp user trap Tycho Andersen
2018-10-29 23:31 ` Serge E. Hallyn
2018-10-30 2:05 ` Tycho Andersen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20181130101751.GA23670@redhat.com \
--to=oleg@redhat.com \
--cc=asarai@suse.de \
--cc=christian@brauner.io \
--cc=containers@lists.linux-foundation.org \
--cc=ebiederm@xmission.com \
--cc=keescook@chromium.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@amacapital.net \
--cc=serge@hallyn.com \
--cc=suda.akihiro@lab.ntt.co.jp \
--cc=tycho@tycho.ws \
--cc=tyhicks@canonical.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.