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References: <20180824224117.3356-1-casey.schaufler@intel.com> <20180824224117.3356-4-casey.schaufler@intel.com>
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From:   Jann Horn <jannh@google.com>
Date:   Sat, 25 Aug 2018 01:17:37 +0200
Message-ID: <CAG48ez0jY6xV+nQdYRy4aT3oH+8FwAM_6MOVFQ3jwYe4Nz+KnA@mail.gmail.com>
Subject: Re: [PATCH v4 3/5] LSM: Security module checking for side-channel dangers
To:     Casey Schaufler <casey.schaufler@intel.com>
Cc:     Kernel Hardening <kernel-hardening@lists.openwall.com>,
        kernel list <linux-kernel@vger.kernel.org>,
        linux-security-module <linux-security-module@vger.kernel.org>,
        selinux@tycho.nsa.gov, Dave Hansen <dave.hansen@intel.com>,
        deneen.t.dock@intel.com, kristen@linux.intel.com,
        Arjan van de Ven <arjan@linux.intel.com>
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On Sat, Aug 25, 2018 at 12:42 AM Casey Schaufler
<casey.schaufler@intel.com> wrote:
> +config SECURITY_SIDECHANNEL_CAPABILITIES
> +       bool "Sidechannel check on capability sets"
> +       depends on SECURITY_SIDECHANNEL
> +       depends on !SECURITY_SIDECHANNEL_ALWAYS
> +       default n
> +       select SECURITY_SIDECHANNEL_NAMESPACES if USER_NS
> +       help
> +         Assume that tasks with different sets of privilege may be
> +         subject to side-channel attacks. Potential interactions
> +         where the attacker lacks capabilities the attacked has
> +         are blocked. Selecting this when user namespaces (USER_NS)
> +         are enabled will enable SECURITY_SIDECHANNEL_NAMESPACES.

Thanks!