Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <4F3D7500.2070604@zytor.com>
Date: Thu, 16 Feb 2012 13:28:32 -0800
From: "H. Peter Anvin" <hpa@...or.com>
To: Will Drewry <wad@...omium.org>
CC: Markus Gutschke <markus@...omium.org>, linux-kernel@...r.kernel.org,
        linux-arch@...r.kernel.org, linux-doc@...r.kernel.org,
        kernel-hardening@...ts.openwall.com, netdev@...r.kernel.org,
        x86@...nel.org, arnd@...db.de, davem@...emloft.net, mingo@...hat.com,
        oleg@...hat.com, peterz@...radead.org, rdunlap@...otime.net,
        mcgrathr@...omium.org, tglx@...utronix.de, luto@....edu,
        eparis@...hat.com, serge.hallyn@...onical.com, djm@...drot.org,
        scarybeasts@...il.com, indan@....nu, pmoore@...hat.com,
        akpm@...ux-foundation.org, corbet@....net, eric.dumazet@...il.com,
        keescook@...omium.org
Subject: Re: [PATCH v8 5/8] seccomp: Add SECCOMP_RET_TRAP

On 02/16/2012 12:42 PM, Will Drewry wrote:
> On Thu, Feb 16, 2012 at 2:24 PM, Markus Gutschke <markus@...omium.org> wrote:
>> SIGTRAP might not be the ideal choice of signal number, as it can make it
>> very difficult to debug the program in gdb.
> 
> True enough.  In theory, we could use the lower 16-bits of the return
> value to let the bpf program set a signal, but not all signals are
> masked synchronous and those that are probably get gdb's attention,
> just not a severely :) (ILL, SEGV, BUS, TRAP, FPE). Perhaps SIGILL is
> a logically appropriate option -- or letting the api user decide from
> the SYNCHRONOUS_MASK set.  I'm open to whatever makes sense, though.
> (I wasn't even sure if it was kosher to add a new TRAP_SECCOMP value.)
> 

There is a standard signal for this -- SIGSYS -- which happens to be
currently unused in Linux.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.

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.