arm64: KVM: Sanitize PSTATE.M when being set from userspace (2a3f9345) · Commits · 戴 / test

Not all execution modes are valid for a guest, and some of them depend on what the HW actually supports. Let's verify that what userspace provides is compatible with both the VM settings and the HW capabilities. Cc: <stable@vger.kernel.org> Fixes: ("arm64: KVM: enable initialization of a 32bit vcpu") Reviewed-by:

Christoffer Dall <christoffer.dall@arm.com> Reviewed-by:

Mark Rutland <mark.rutland@arm.com> Reviewed-by:

Dave Martin <Dave.Martin@arm.com> Signed-off-by:

Marc Zyngier <marc.zyngier@arm.com> Signed-off-by:

Will Deacon <will.deacon@arm.com>

arch/arm64/kvm/guest.c

+9 −1

Original line number	Original line	Diff line number	Diff line
	@@ -152,17 +152,25 @@ static int set_core_reg(struct kvm_vcpu vcpu, const struct kvm_one_reg reg)
	}		}

	if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {		if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
	u32 mode = ((u32 )valp) & PSR_AA32_MODE_MASK;		u64 mode = ((u64 )valp) & PSR_AA32_MODE_MASK;
	switch (mode) {		switch (mode) {
	case PSR_AA32_MODE_USR:		case PSR_AA32_MODE_USR:
			if (!system_supports_32bit_el0())
			return -EINVAL;
			break;
	case PSR_AA32_MODE_FIQ:		case PSR_AA32_MODE_FIQ:
	case PSR_AA32_MODE_IRQ:		case PSR_AA32_MODE_IRQ:
	case PSR_AA32_MODE_SVC:		case PSR_AA32_MODE_SVC:
	case PSR_AA32_MODE_ABT:		case PSR_AA32_MODE_ABT:
	case PSR_AA32_MODE_UND:		case PSR_AA32_MODE_UND:
			if (!vcpu_el1_is_32bit(vcpu))
			return -EINVAL;
			break;
	case PSR_MODE_EL0t:		case PSR_MODE_EL0t:
	case PSR_MODE_EL1t:		case PSR_MODE_EL1t:
	case PSR_MODE_EL1h:		case PSR_MODE_EL1h:
			if (vcpu_el1_is_32bit(vcpu))
			return -EINVAL;
	break;		break;
	default:		default:
	err = -EINVAL;		err = -EINVAL;

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