From: Kristina Martsenko <kristina.martsenko@arm.com>
Date: Wed, 1 May 2019 16:10:08 +0000 (+0100)
Subject: KVM: arm64: Fix ptrauth ID register masking logic
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=9eecfc22e0bfc7a4c8ca007f083f0ae492d6e891;p=openwrt%2Fstaging%2Fblogic.git

KVM: arm64: Fix ptrauth ID register masking logic

When a VCPU doesn't have pointer auth, we want to hide all four pointer
auth ID register fields from the guest, not just one of them.

Fixes: 384b40caa8af ("KVM: arm/arm64: Context-switch ptrauth registers")
Reported-by: Andrew Murray <andrew.murray@arm.com>
Fscked-up-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 9d02643bc601..857b226bcdde 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1088,10 +1088,10 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu,
 	if (id == SYS_ID_AA64PFR0_EL1 && !vcpu_has_sve(vcpu)) {
 		val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT);
 	} else if (id == SYS_ID_AA64ISAR1_EL1 && !vcpu_has_ptrauth(vcpu)) {
-		val &= ~(0xfUL << ID_AA64ISAR1_APA_SHIFT) |
-			(0xfUL << ID_AA64ISAR1_API_SHIFT) |
-			(0xfUL << ID_AA64ISAR1_GPA_SHIFT) |
-			(0xfUL << ID_AA64ISAR1_GPI_SHIFT);
+		val &= ~((0xfUL << ID_AA64ISAR1_APA_SHIFT) |
+			 (0xfUL << ID_AA64ISAR1_API_SHIFT) |
+			 (0xfUL << ID_AA64ISAR1_GPA_SHIFT) |
+			 (0xfUL << ID_AA64ISAR1_GPI_SHIFT));
 	}
 
 	return val;