evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

arm64: KVM: Sanitize PSTATE.M when being set from userspace

Browse source 
commit 2a3f93459d689d990b3ecfbe782fec89b97d3279 upstream.

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: 0d854a60b1 ("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>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Marc Zyngier 2018-09-27 16:53:22 +01:00 • committed by Greg Kroah-Hartman
parent fdbd625224
commit ae22586bb5
2 changed files with 14 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

5
arch/arm64/include/asm/kvm_emulate.h
View file

@ -41,6 +41,11 @@ void kvm_inject_undefined(struct kvm_vcpu *vcpu);
void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr);
void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
static inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu)
{
return !(vcpu->arch.hcr_el2 & HCR_RW);
}
static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
{
vcpu->arch.hcr_el2 = HCR_GUEST_FLAGS;

10
arch/arm64/kvm/guest.c
View file

@ -143,17 +143,25 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
}
if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
u32 mode = (*(u32 *)valp) & COMPAT_PSR_MODE_MASK;
u64 mode = (*(u64 *)valp) & COMPAT_PSR_MODE_MASK;
switch (mode) {
case COMPAT_PSR_MODE_USR:
if (!system_supports_32bit_el0())
return -EINVAL;
break;
case COMPAT_PSR_MODE_FIQ:
case COMPAT_PSR_MODE_IRQ:
case COMPAT_PSR_MODE_SVC:
case COMPAT_PSR_MODE_ABT:
case COMPAT_PSR_MODE_UND:
if (!vcpu_el1_is_32bit(vcpu))
return -EINVAL;
break;
case PSR_MODE_EL0t:
case PSR_MODE_EL1t:
case PSR_MODE_EL1h:
if (vcpu_el1_is_32bit(vcpu))
return -EINVAL;
break;
default:
err = -EINVAL;