KVM: MMU: bail out pagewalk on kvm_read_guest error



Exit the guest pagetable walk loop if reading gpte failed. Otherwise its
possible to enter an endless loop processing the previous present pte.

Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

parent d72118ce

arch/x86/kvm/paging_tmpl.h

+3 −1

Original line number	Diff line number	Diff line
		@@ -150,7 +150,9 @@ static int FNAME(walk_addr)(struct guest_walker *walker,
		walker->table_gfn[walker->level - 1] = table_gfn;
		walker->pte_gpa[walker->level - 1] = pte_gpa;

		kvm_read_guest(vcpu->kvm, pte_gpa, &pte, sizeof(pte));
		if (kvm_read_guest(vcpu->kvm, pte_gpa, &pte, sizeof(pte)))
		goto not_present;

		trace_kvm_mmu_paging_element(pte, walker->level);

		if (!is_present_gpte(pte))