diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c index b9d0992e9197..adcfce3f67f0 100644 --- a/arch/arm64/kvm/at.c +++ b/arch/arm64/kvm/at.c @@ -37,6 +37,12 @@ struct s1_walk_result { u8 APTable; bool UXNTable; bool PXNTable; + bool ur; + bool uw; + bool ux; + bool pr; + bool pw; + bool px; }; struct { u8 fst; @@ -764,11 +770,103 @@ static bool pan3_enabled(struct kvm_vcpu *vcpu, enum trans_regime regime) return sctlr & SCTLR_EL1_EPAN; } +static void compute_s1_direct_permissions(struct kvm_vcpu *vcpu, + struct s1_walk_info *wi, + struct s1_walk_result *wr) +{ + /* Non-hierarchical part of AArch64.S1DirectBasePermissions() */ + if (wi->regime != TR_EL2) { + switch (FIELD_GET(PTE_USER | PTE_RDONLY, wr->desc)) { + case 0b00: + wr->pr = wr->pw = true; + wr->ur = wr->uw = false; + break; + case 0b01: + wr->pr = wr->pw = wr->ur = wr->uw = true; + break; + case 0b10: + wr->pr = true; + wr->pw = wr->ur = wr->uw = false; + break; + case 0b11: + wr->pr = wr->ur = true; + wr->pw = wr->uw = false; + break; + } + + /* We don't use px for anything yet, but hey... */ + wr->px = !((wr->desc & PTE_PXN) || wr->uw); + wr->ux = !(wr->desc & PTE_UXN); + } else { + wr->ur = wr->uw = wr->ux = false; + + if (!(wr->desc & PTE_RDONLY)) { + wr->pr = wr->pw = true; + } else { + wr->pr = true; + wr->pw = false; + } + + /* XN maps to UXN */ + wr->px = !(wr->desc & PTE_UXN); + } +} + +static void compute_s1_hierarchical_permissions(struct kvm_vcpu *vcpu, + struct s1_walk_info *wi, + struct s1_walk_result *wr) +{ + /* Hierarchical part of AArch64.S1DirectBasePermissions() */ + if (wi->regime != TR_EL2) { + switch (wr->APTable) { + case 0b00: + break; + case 0b01: + wr->ur = wr->uw = false; + break; + case 0b10: + wr->pw = wr->uw = false; + break; + case 0b11: + wr->pw = wr->ur = wr->uw = false; + break; + } + + wr->px &= !wr->PXNTable; + wr->ux &= !wr->UXNTable; + } else { + if (wr->APTable & BIT(1)) + wr->pw = false; + + /* XN maps to UXN */ + wr->px &= !wr->UXNTable; + } +} + +static void compute_s1_permissions(struct kvm_vcpu *vcpu, u32 op, + struct s1_walk_info *wi, + struct s1_walk_result *wr) +{ + compute_s1_direct_permissions(vcpu, wi, wr); + + if (!wi->hpd) + compute_s1_hierarchical_permissions(vcpu, wi, wr); + + if (op == OP_AT_S1E1RP || op == OP_AT_S1E1WP) { + bool pan; + + pan = *vcpu_cpsr(vcpu) & PSR_PAN_BIT; + pan &= wr->ur || wr->uw || (pan3_enabled(vcpu, wi->regime) && wr->ux); + wr->pw &= !pan; + wr->pr &= !pan; + } +} + static u64 handle_at_slow(struct kvm_vcpu *vcpu, u32 op, u64 vaddr) { - bool perm_fail, ur, uw, ux, pr, pw, px; struct s1_walk_result wr = {}; struct s1_walk_info wi = {}; + bool perm_fail = false; int ret, idx; ret = setup_s1_walk(vcpu, op, &wi, &wr, vaddr); @@ -787,88 +885,24 @@ static u64 handle_at_slow(struct kvm_vcpu *vcpu, u32 op, u64 vaddr) if (ret) goto compute_par; - /* FIXME: revisit when adding indirect permission support */ - /* AArch64.S1DirectBasePermissions() */ - if (wi.regime != TR_EL2) { - switch (FIELD_GET(PTE_USER | PTE_RDONLY, wr.desc)) { - case 0b00: - pr = pw = true; - ur = uw = false; - break; - case 0b01: - pr = pw = ur = uw = true; - break; - case 0b10: - pr = true; - pw = ur = uw = false; - break; - case 0b11: - pr = ur = true; - pw = uw = false; - break; - } - - switch (wr.APTable) { - case 0b00: - break; - case 0b01: - ur = uw = false; - break; - case 0b10: - pw = uw = false; - break; - case 0b11: - pw = ur = uw = false; - break; - } - - /* We don't use px for anything yet, but hey... */ - px = !((wr.desc & PTE_PXN) || wr.PXNTable || uw); - ux = !((wr.desc & PTE_UXN) || wr.UXNTable); - - if (op == OP_AT_S1E1RP || op == OP_AT_S1E1WP) { - bool pan; - - pan = *vcpu_cpsr(vcpu) & PSR_PAN_BIT; - pan &= ur || uw || (pan3_enabled(vcpu, wi.regime) && ux); - pw &= !pan; - pr &= !pan; - } - } else { - ur = uw = ux = false; - - if (!(wr.desc & PTE_RDONLY)) { - pr = pw = true; - } else { - pr = true; - pw = false; - } - - if (wr.APTable & BIT(1)) - pw = false; - - /* XN maps to UXN */ - px = !((wr.desc & PTE_UXN) || wr.UXNTable); - } - - perm_fail = false; + compute_s1_permissions(vcpu, op, &wi, &wr); switch (op) { case OP_AT_S1E1RP: case OP_AT_S1E1R: case OP_AT_S1E2R: - perm_fail = !pr; + perm_fail = !wr.pr; break; case OP_AT_S1E1WP: case OP_AT_S1E1W: case OP_AT_S1E2W: - perm_fail = !pw; + perm_fail = !wr.pw; break; case OP_AT_S1E0R: - perm_fail = !ur; + perm_fail = !wr.ur; break; case OP_AT_S1E0W: - perm_fail = !uw; + perm_fail = !wr.uw; break; case OP_AT_S1E1A: case OP_AT_S1E2A: