linux-kernel - Re: [PATCH] fs/proc: report eip/esp in /prod/PID/stat for coredumping

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, 14 Sep 2017 07:51:59 -0700
From:   Andy Lutomirski <luto@...nel.org>
To:     John Ogness <john.ogness@...utronix.de>
Cc:     Andy Lutomirski <luto@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Al Viro <viro@...iv.linux.org.uk>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Borislav Petkov <bp@...en8.de>,
        Brian Gerst <brgerst@...il.com>,
        Kees Cook <keescook@...omium.org>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Linux API <linux-api@...r.kernel.org>,
        Peter Zijlstra <peterz@...radead.org>,
        Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>,
        Tycho Andersen <tycho.andersen@...onical.com>,
        Ingo Molnar <mingo@...nel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        stable <stable@...r.kernel.org>
Subject: Re: [PATCH] fs/proc: report eip/esp in /prod/PID/stat for coredumping

On Thu, Sep 14, 2017 at 2:42 AM, John Ogness <john.ogness@...utronix.de> wrote:
> Commit 0a1eb2d474ed ("fs/proc: Stop reporting eip and esp in
> /proc/PID/stat") stopped reporting eip/esp because it is
> racey and dangerous for executing tasks. The comment adds:
>
>     As far as I know, there are no use programs that make any
>     material use of these fields, so just get rid of them.
>
> However, existing userspace core-dump-handler applications (for
> example, minicoredumper) are using these fields since they
> provide an excellent cross-platform interface to these valuable
> pointers. So that commit introduced a user space visible
> regression.
>
> Partially revert the change and make the readout possible for
> tasks with the proper permissions and only if the target task
> has the PF_DUMPCORE flag set.

Looks okay to me.

Reviewed-by: Andy Lutomirski <luto@...nel.org>

--Andy