From b5040c57435df2a2320c2eb9bcca231fd8b4c65f Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 21 Jun 2021 15:47:20 +0100 Subject: [PATCH] ANDROID: KVM: arm64: Check for PTE validity when checking for executable/cacheable 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 Signed-off-by: Marc Zyngier Signed-off-by: Will Deacon Bug: 233587962 Change-Id: I6cbcdb97033ec7b2ed2c9dce0cfc91491e573908 --- 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 2bcb2d5903ba..362a3fdf651f 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -688,12 +688,12 @@ 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, @@ -738,8 +738,7 @@ 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); @@ -1136,7 +1135,7 @@ static int stage2_flush_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, struct kvm_pgtable_mm_ops *mm_ops = pgt->mm_ops; kvm_pte_t pte = *ptep; - if (!kvm_pte_valid(pte) || !stage2_pte_cacheable(pgt, pte)) + if (!stage2_pte_cacheable(pgt, pte)) return 0; if (mm_ops->dcache_clean_inval_poc)