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Message-ID: <a36005b50603130716x4cc5306ex2f8ecf012ea052d1@mail.gmail.com>
Date: Mon, 13 Mar 2006 07:16:17 -0800
From: "Ulrich Drepper" <drepper@gmail.com>
To: "GOTO Masanori" <gotom@sanori.org>
Subject: Re: [PATCH] Fix sigaltstack corruption among cloned threads
Cc: akpm@osdl.org, linux-kernel@vger.kernel.org
In-Reply-To: <81ek16loay.wl%gotom@sanori.org>
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On 3/13/06, GOTO Masanori <gotom@sanori.org> wrote:
> +        * sigaltstack should be cleared when CLONE_SIGHAND (and CLONE_VM) is
> +        * specified.
> +        */
> +       if (clone_flags & CLONE_SIGHAND)
> +               p->sas_ss_sp = p->sas_ss_size = 0;

I agree in general, but why base it on CLONE_SIGHAND? The problem
results from using the same address space.  So it should be

  if (clone_flags & CLONE_VM)

The fact that both these flags are used at the same time in all cases
today shouldn't hide the real reason for this requirement which is
sharing the address space.
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