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From 718d9b380174eb8fe16d67769395737b79654a02 Mon Sep 17 00:00:00 2001
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Date: Thu, 9 Jul 2020 08:59:30 +0530
Subject: [PATCH] powerpc/book3s64/pkeys: Prevent key 1 modification from
 userspace.

References: jsc#SLE-16556 bsc#1078248 FATE#322447
Patch-mainline: v5.9-rc1
Git-commit: 718d9b380174eb8fe16d67769395737b79654a02

Key 1 is marked reserved by ISA. Setup uamor to prevent userspace modification
of the same.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200709032946.881753-8-aneesh.kumar@linux.ibm.com
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 arch/powerpc/mm/book3s64/pkeys.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 2dea8c29df57..e2bf93901bd0 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -183,6 +183,7 @@ static int pkey_initialize(void)
 	 * programming note.
 	 */
 	reserved_allocation_mask |= (0x1 << 1);
+	default_uamor &= ~(0x3ul << pkeyshift(1));
 
 	/*
 	 * Prevent the usage of OS reserved the keys. Update UAMOR
-- 
2.26.2