From 781c64bfcb735960717d1cb45428047ff6a5030c Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 24 Mar 2022 14:47:14 +0100 Subject: [PATCH] x86/fpu/xstate: Handle supervisor states in XSTATE permissions The size calculation in __xstate_request_perm() fails to take supervisor states into account because the permission bitmap is only relevant for user states. Up to 5.17 this does not matter because there are no supervisor states supported, but the (re-)enabling of ENQCMD makes them available. Fixes: 7c1ef59145f1 ("x86/cpufeatures: Re-enable ENQCMD") Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/r/20220324134623.681768598@linutronix.de --- arch/x86/kernel/fpu/xstate.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index c55f72e..5ac934b 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1571,6 +1571,9 @@ static int __xstate_request_perm(u64 permitted, u64 requested, bool guest) /* Calculate the resulting kernel state size */ mask = permitted | requested; + /* Take supervisor states into account on the host */ + if (!guest) + mask |= xfeatures_mask_supervisor(); ksize = xstate_calculate_size(mask, compacted); /* Calculate the resulting user state size */ -- 2.7.4