Messages in this thread | | | From | Tim Chen <> | Subject | Re: [PATCH 2/2] x86/speculation: Provide application property based STIBP protection | Date | Thu, 20 Sep 2018 10:32:20 -0700 |
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On 09/20/2018 01:00 AM, Peter Zijlstra wrote: > On Wed, Sep 19, 2018 at 02:35:30PM -0700, Tim Chen wrote: >> This patch provides an application property based spectre_v2 >> protection with STIBP against attack from another app from >> a sibling hyper-thread. For security sensitive non-dumpable >> app, STIBP will be turned on before switching to it for Intel >> processors vulnerable to spectre_v2. > > Why does that non dumpable thing make sense? Why not use the same > prctl() we already use for SSBD? >
Something like the following?
prctl(PR_GET_SPECULATION_CTRL, PR_SPEC_SPECTREV2_APP, 0, 0, 0); prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_SPECTREV2_APP, PR_SPEC_ENABLE, 0, 0); prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_SPECTREV2_APP, PR_SPEC_DISABLE, 0, 0); prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_SPECTREV2_APP, PR_SPEC_FORCE_DISABLE, 0, 0);
People may have already made changes to their app using non-dumpable to mitigate app-app attack. So I think we should still protect the non-dumpable processes so they don't have to change their application code.
Tim
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