[PATCH 5.18 305/339] KVM: x86/mmu: Check every prev_roots in __kvm_mmu_free_obsolete_roots()

[Greg Kroah-Hartman]

From: Shaoqin Huang <shaoqin.huang@xxxxxxxxx>

commit cf4a8693d97a51dccf5a1557248d12d6d8be4b9e upstream.

When freeing obsolete previous roots, check prev_roots as intended, not
the current root.

Signed-off-by: Shaoqin Huang <shaoqin.huang@xxxxxxxxx>
Fixes: 527d5cd7eece ("KVM: x86/mmu: Zap only obsolete roots if a root shadow page is zapped")
Message-Id: <20220607005905.2933378-1-shaoqin.huang@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/x86/kvm/mmu/mmu.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5168,7 +5168,7 @@ static void __kvm_mmu_free_obsolete_root
 		roots_to_free |= KVM_MMU_ROOT_CURRENT;
 
 	for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
-		if (is_obsolete_root(kvm, mmu->root.hpa))
+		if (is_obsolete_root(kvm, mmu->prev_roots[i].hpa))
 			roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i);
 	}