Don't blindly assume that the PTE is valid when checking whether it describes an executable or cacheable mapping. This makes sure that we don't issue CMOs for invalid mappings. Suggested-by: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> --- arch/arm64/kvm/hyp/pgtable.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index f8ceebe4982e..6bbfd952f0c5 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -638,12 +638,12 @@ static void stage2_put_pte(kvm_pte_t *ptep, struct kvm_s2_mmu *mmu, u64 addr, static bool stage2_pte_cacheable(struct kvm_pgtable *pgt, kvm_pte_t pte) { u64 memattr = pte & KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR; - return memattr == KVM_S2_MEMATTR(pgt, NORMAL); + return kvm_pte_valid(pte) && memattr == KVM_S2_MEMATTR(pgt, NORMAL); } static bool stage2_pte_executable(kvm_pte_t pte) { - return !(pte & KVM_PTE_LEAF_ATTR_HI_S2_XN); + return kvm_pte_valid(pte) && !(pte & KVM_PTE_LEAF_ATTR_HI_S2_XN); } static bool stage2_leaf_mapping_allowed(u64 addr, u64 end, u32 level, @@ -688,8 +688,7 @@ static int stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level, /* Perform CMOs before installation of the guest stage-2 PTE */ if (mm_ops->dcache_clean_inval_poc && stage2_pte_cacheable(pgt, new)) mm_ops->dcache_clean_inval_poc(kvm_pte_follow(new, mm_ops), - granule); - + granule); if (mm_ops->icache_inval_pou && stage2_pte_executable(new)) mm_ops->icache_inval_pou(kvm_pte_follow(new, mm_ops), granule); @@ -1091,7 +1090,7 @@ static int stage2_flush_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, kvm_pte_t pte = *ptep; kvm_pte_t *pte_follow; - if (!kvm_pte_valid(pte) || !stage2_pte_cacheable(pgt, pte)) + if (!stage2_pte_cacheable(pgt, pte)) return 0; pte_follow = kvm_pte_follow(pte, mm_ops); -- 2.30.2