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	for speck@linutronix.de; Tue, 01 May 2018 23:45:13 +0200
Date: Tue, 1 May 2018 23:45:12 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [patch V8 15/15] SSB 15
In-Reply-To: <20180430221547.GH8398@outflux.net>
Message-ID: <alpine.DEB.2.21.1805012338420.1596@nanos.tec.linutronix.de>
References: <20180430150423.180110059@linutronix.de>
 <20180430151233.029064226@linutronix.de> <20180430221547.GH8398@outflux.net>
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To: speck@linutronix.de
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On Mon, 30 Apr 2018, speck for Kees Cook wrote:
> diff --git a/fs/proc/array.c b/fs/proc/array.c
> index ae2c807fd719..4a5cdf199fde 100644
> --- a/fs/proc/array.c
> +++ b/fs/proc/array.c
> @@ -335,6 +335,25 @@ static inline void task_seccomp(struct seq_file *m, struct task_struct *p)
>  #ifdef CONFIG_SECCOMP
>  	seq_put_decimal_ull(m, "\nSeccomp:\t", p->seccomp.mode);
>  #endif
> +	seq_printf(m, "\nSpeculation, Store Bypass:\t");
> +	switch (arch_prctl_get_spec_ctrl(PR_SPEC_STORE_BYPASS)) {
> +	case -EINVAL:
> +		seq_printf(m, "unknown");
> +		break;
> +	case PR_SPEC_NOT_AFFECTED:
> +		seq_printf(m, "not vulnerable");
> +		break;
> +	case PR_SPEC_PRCTL:
> +		seq_printf(m, test_tsk_thread_flag(p, TIF_RDS) ?

Breaks non x86 as well. Seems to be a common theme...

> +				"thread mitigated" : "thread vulnerable");
> +		break;
> +	case PR_SPEC_DISABLE:
> +		seq_printf(m, "globally mitigated");
> +		break;
> +	default:
> +		seq_printf(m, "vulnerable");
> +		break;
> +	}
>  	seq_putc(m, '\n');

No TIF_RDS required at all. arch_prctl_get_spec_ctrl() gives you all the
info already.

	switch (arch_prctl_get_spec_ctrl(PR_SPEC_STORE_BYPASS)) {
	case -EINVAL:
		seq_printf(m, "unknown");
		break;
	case PR_SPEC_NOT_AFFECTED:
		seq_printf(m, "not vulnerable");
		break;
	case PR_SPEC_PRCTL | PR_SPEC_DISABLE:
	     	seq_printf(m, "thread mitigated");
		break;
	case PR_SPEC_PRCTL | PR_SPEC_ENABLE:
	     	seq_printf(m, "thread vulnerable");
		break;
	case PR_SPEC_DISABLE:
		seq_printf(m, "globally mitigated");
		break;
	default:
		seq_printf(m, "vulnerable");
		break;
	}
 	seq_putc(m, '\n');

Thanks,

	tglx