From: Dan Carpenter <dan.carpenter@linaro.org>
Date: Mon, 24 Mar 2025 10:51:28 +0000 (+0300)
Subject: KVM: x86: Check that the high 32bits are clear in kvm_arch_vcpu_ioctl_run()
X-Git-Tag: v6.15-rc6~1^2^2~4
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a476cadf8ef1fbb9780581316f0199dfc62a81f2;p=thirdparty%2Fkernel%2Flinux.git

KVM: x86: Check that the high 32bits are clear in kvm_arch_vcpu_ioctl_run()

The "kvm_run->kvm_valid_regs" and "kvm_run->kvm_dirty_regs" variables are
u64 type.  We are only using the lowest 3 bits but we want to ensure that
the users are not passing invalid bits so that we can use the remaining
bits in the future.

However "sync_valid_fields" and kvm_sync_valid_fields() are u32 type so
the check only ensures that the lower 32 bits are clear.  Fix this by
changing the types to u64.

Fixes: 74c1807f6c4f ("KVM: x86: block KVM_CAP_SYNC_REGS if guest state is protected")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/ec25aad1-113e-4c6e-8941-43d432251398@stanley.mountain
Signed-off-by: Sean Christopherson <seanjc@google.com>
---

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index df5b99ea1f181..9896fd574bfc9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4597,7 +4597,7 @@ static bool kvm_is_vm_type_supported(unsigned long type)
 	return type < 32 && (kvm_caps.supported_vm_types & BIT(type));
 }
 
-static inline u32 kvm_sync_valid_fields(struct kvm *kvm)
+static inline u64 kvm_sync_valid_fields(struct kvm *kvm)
 {
 	return kvm && kvm->arch.has_protected_state ? 0 : KVM_SYNC_X86_VALID_FIELDS;
 }
@@ -11493,7 +11493,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 {
 	struct kvm_queued_exception *ex = &vcpu->arch.exception;
 	struct kvm_run *kvm_run = vcpu->run;
-	u32 sync_valid_fields;
+	u64 sync_valid_fields;
 	int r;
 
 	r = kvm_mmu_post_init_vm(vcpu->kvm);