[RFC,v1,17/34] KVM: introspection: extend the access rights database with EPT view info

Message ID	20200722160121.9601-18-alazar@bitdefender.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <SRS0=byMP=BB=vger.kernel.org=kvm-owner@kernel.org> From: =?utf-8?q?Adalbert_Laz=C4=83r?= <alazar@bitdefender.com> To: kvm@vger.kernel.org Cc: virtualization@lists.linux-foundation.org, Paolo Bonzini <pbonzini@redhat.com>, =?utf-8?q?=C8=98tefan_=C8=98icleru?= <ssicleru@bitdefender.com>, =?utf-8?q?Adalbert_Laz=C4=83r?= <alazar@bitdefender.com> Subject: [RFC PATCH v1 17/34] KVM: introspection: extend the access rights database with EPT view info Date: Wed, 22 Jul 2020 19:01:04 +0300 Message-Id: <20200722160121.9601-18-alazar@bitdefender.com> In-Reply-To: <20200722160121.9601-1-alazar@bitdefender.com> References: <20200722160121.9601-1-alazar@bitdefender.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: kvm-owner@vger.kernel.org Precedence: bulk
Series	VM introspection - EPT Views and Virtualization Exceptions \| expand [RFC,v1,00/34] VM introspection - EPT Views and Virtualization Exceptions [RFC,v1,01/34] KVM: x86: export .get_vmfunc_status() [RFC,v1,02/34] KVM: x86: export .get_eptp_switching_status() [RFC,v1,03/34] KVM: x86: add kvm_get_ept_view() [RFC,v1,04/34] KVM: x86: mmu: reindent to avoid lines longer than 80 chars [RFC,v1,05/34] KVM: x86: mmu: add EPT view parameter to kvm_mmu_get_page() [RFC,v1,06/34] KVM: x86: mmu: add support for EPT switching [RFC,v1,07/34] KVM: x86: mmu: increase mmu_memory_cache size [RFC,v1,08/34] KVM: x86: add .set_ept_view() [RFC,v1,09/34] KVM: x86: add .control_ept_view() [RFC,v1,10/34] KVM: x86: page track: allow page tracking for different EPT views [RFC,v1,11/34] KVM: x86: mmu: allow zapping shadow pages for specific EPT views [RFC,v1,12/34] KVM: introspection: extend struct kvmi_features with the EPT views status support [RFC,v1,13/34] KVM: introspection: add KVMI_VCPU_GET_EPT_VIEW [RFC,v1,14/34] KVM: introspection: add 'view' field to struct kvmi_event_arch [RFC,v1,15/34] KVM: introspection: add KVMI_VCPU_SET_EPT_VIEW [RFC,v1,16/34] KVM: introspection: add KVMI_VCPU_CONTROL_EPT_VIEW [RFC,v1,17/34] KVM: introspection: extend the access rights database with EPT view info [RFC,v1,18/34] KVM: introspection: extend KVMI_VM_SET_PAGE_ACCESS with EPT view info [RFC,v1,19/34] KVM: introspection: clean non-default EPTs on unhook [RFC,v1,20/34] KVM: x86: vmx: add support for virtualization exceptions [RFC,v1,21/34] KVM: VMX: Define EPT suppress #VE bit (bit 63 in EPT leaf entries) [RFC,v1,22/34] KVM: VMX: Suppress EPT violation #VE by default (when enabled) [RFC,v1,23/34] KVM: x86: mmu: fix: update present_mask in spte_read_protect() [RFC,v1,24/34] KVM: vmx: trigger vm-exits for mmio sptes by default when #VE is enabled [RFC,v1,25/34] KVM: x86: svm: set .clear_page() [RFC,v1,26/34] KVM: x86: add .set_ve_info() [RFC,v1,27/34] KVM: x86: add .disable_ve() [RFC,v1,28/34] KVM: x86: page_track: add support for suppress #VE bit [RFC,v1,29/34] KVM: vmx: make use of EPTP_INDEX in vmx_handle_exit() [RFC,v1,30/34] KVM: vmx: make use of EPTP_INDEX in vmx_set_ept_view() [RFC,v1,31/34] KVM: introspection: add #VE host capability checker [RFC,v1,32/34] KVM: introspection: add KVMI_VCPU_SET_VE_INFO/KVMI_VCPU_DISABLE_VE [RFC,v1,33/34] KVM: introspection: mask out non-rwx flags when reading/writing from/to the internal… [RFC,v1,34/34] KVM: introspection: add KVMI_VM_SET_PAGE_SVE

diff --git a/arch/x86/include/asm/kvmi_host.h b/arch/x86/include/asm/kvmi_host.h index 509fa3fff5e7..8af03ba38316 100644 --- a/arch/x86/include/asm/kvmi_host.h +++ b/arch/x86/include/asm/kvmi_host.h @@ -9,6 +9,7 @@ struct msr_data; #define KVMI_NUM_CR 5 #define KVMI_NUM_MSR 0x2000 +#define KVMI_MAX_ACCESS_TREES KVM_MAX_EPT_VIEWS struct kvmi_monitor_interception { bool kvmi_intercepted; diff --git a/arch/x86/kvm/kvmi.c b/arch/x86/kvm/kvmi.c index 06357b8ab54a..52885b9e5b6e 100644 --- a/arch/x86/kvm/kvmi.c +++ b/arch/x86/kvm/kvmi.c @@ -1197,7 +1197,7 @@ static const struct { void kvmi_arch_update_page_tracking(struct kvm *kvm, struct kvm_memory_slot *slot, - struct kvmi_mem_access *m) + struct kvmi_mem_access *m, u16 view) { struct kvmi_arch_mem_access *arch = &m->arch; int i; @@ -1217,12 +1217,12 @@ void kvmi_arch_update_page_tracking(struct kvm *kvm, if (slot_tracked) { kvm_slot_page_track_remove_page(kvm, slot, m->gfn, mode, - 0); + view); clear_bit(slot->id, arch->active[mode]); } } else if (!slot_tracked) { kvm_slot_page_track_add_page(kvm, slot, m->gfn, mode, - 0); + view); set_bit(slot->id, arch->active[mode]); } } @@ -1256,7 +1256,8 @@ static bool is_pf_of_interest(struct kvm_vcpu *vcpu, gpa_t gpa, u8 access) if (kvm_x86_ops.gpt_translation_fault(vcpu)) return false; - return kvmi_restricted_page_access(KVMI(vcpu->kvm), gpa, access); + return kvmi_restricted_page_access(KVMI(vcpu->kvm), gpa, access, + kvm_get_ept_view(vcpu)); } static bool handle_pf_event(struct kvm_vcpu *vcpu, gpa_t gpa, gva_t gva, diff --git a/include/linux/kvmi_host.h b/include/linux/kvmi_host.h index 5baef68d8cbe..c38c7f16d5d0 100644 --- a/include/linux/kvmi_host.h +++ b/include/linux/kvmi_host.h @@ -69,7 +69,7 @@ struct kvm_introspection { bool cleanup_on_unhook; - struct radix_tree_root access_tree; + struct radix_tree_root access_tree[KVMI_MAX_ACCESS_TREES]; rwlock_t access_tree_lock; }; diff --git a/virt/kvm/introspection/kvmi.c b/virt/kvm/introspection/kvmi.c index 2a96b80bddb2..737fe3c7a956 100644 --- a/virt/kvm/introspection/kvmi.c +++ b/virt/kvm/introspection/kvmi.c @@ -258,20 +258,23 @@ static void kvmi_clear_mem_access(struct kvm *kvm) struct kvm_introspection *kvmi = KVMI(kvm); struct radix_tree_iter iter; void **slot; - int idx; + int idx, view; idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); - radix_tree_for_each_slot(slot, &kvmi->access_tree, &iter, 0) { - struct kvmi_mem_access *m = *slot; + for (view = 0; view < KVMI_MAX_ACCESS_TREES; view++) + radix_tree_for_each_slot(slot, &kvmi->access_tree[view], + &iter, 0) { + struct kvmi_mem_access *m = *slot; - m->access = full_access; - kvmi_arch_update_page_tracking(kvm, NULL, m); + m->access = full_access; + kvmi_arch_update_page_tracking(kvm, NULL, m, view); - radix_tree_iter_delete(&kvmi->access_tree, &iter, slot); - kmem_cache_free(radix_cache, m); - } + radix_tree_iter_delete(&kvmi->access_tree[view], + &iter, slot); + kmem_cache_free(radix_cache, m); + } spin_unlock(&kvm->mmu_lock); srcu_read_unlock(&kvm->srcu, idx); @@ -335,8 +338,9 @@ alloc_kvmi(struct kvm *kvm, const struct kvm_introspection_hook *hook) atomic_set(&kvmi->ev_seq, 0); - INIT_RADIX_TREE(&kvmi->access_tree, - GFP_KERNEL & ~__GFP_DIRECT_RECLAIM); + for (i = 0; i < ARRAY_SIZE(kvmi->access_tree); i++) + INIT_RADIX_TREE(&kvmi->access_tree[i], + GFP_KERNEL & ~__GFP_DIRECT_RECLAIM); rwlock_init(&kvmi->access_tree_lock); kvm_for_each_vcpu(i, vcpu, kvm) { @@ -1065,33 +1069,35 @@ bool kvmi_enter_guest(struct kvm_vcpu *vcpu) } static struct kvmi_mem_access * -__kvmi_get_gfn_access(struct kvm_introspection *kvmi, const gfn_t gfn) +__kvmi_get_gfn_access(struct kvm_introspection *kvmi, const gfn_t gfn, u16 view) { - return radix_tree_lookup(&kvmi->access_tree, gfn); + return radix_tree_lookup(&kvmi->access_tree[view], gfn); } -static void kvmi_update_mem_access(struct kvm *kvm, struct kvmi_mem_access *m) +static void kvmi_update_mem_access(struct kvm *kvm, struct kvmi_mem_access *m, + u16 view) { struct kvm_introspection *kvmi = KVMI(kvm); - kvmi_arch_update_page_tracking(kvm, NULL, m); + kvmi_arch_update_page_tracking(kvm, NULL, m, view); if (m->access == full_access) { - radix_tree_delete(&kvmi->access_tree, m->gfn); + radix_tree_delete(&kvmi->access_tree[view], m->gfn); kmem_cache_free(radix_cache, m); } } -static void kvmi_insert_mem_access(struct kvm *kvm, struct kvmi_mem_access *m) +static void kvmi_insert_mem_access(struct kvm *kvm, struct kvmi_mem_access *m, + u16 view) { struct kvm_introspection *kvmi = KVMI(kvm); - radix_tree_insert(&kvmi->access_tree, m->gfn, m); - kvmi_arch_update_page_tracking(kvm, NULL, m); + radix_tree_insert(&kvmi->access_tree[view], m->gfn, m); + kvmi_arch_update_page_tracking(kvm, NULL, m, view); } static void kvmi_set_mem_access(struct kvm *kvm, struct kvmi_mem_access *m, - bool *used) + u16 view, bool *used) { struct kvm_introspection *kvmi = KVMI(kvm); struct kvmi_mem_access *found; @@ -1101,12 +1107,12 @@ static void kvmi_set_mem_access(struct kvm *kvm, struct kvmi_mem_access *m, spin_lock(&kvm->mmu_lock); write_lock(&kvmi->access_tree_lock); - found = __kvmi_get_gfn_access(kvmi, m->gfn); + found = __kvmi_get_gfn_access(kvmi, m->gfn, view); if (found) { found->access = m->access; - kvmi_update_mem_access(kvm, found); + kvmi_update_mem_access(kvm, found, view); } else if (m->access != full_access) { - kvmi_insert_mem_access(kvm, m); + kvmi_insert_mem_access(kvm, m, view); *used = true; } @@ -1115,7 +1121,8 @@ static void kvmi_set_mem_access(struct kvm *kvm, struct kvmi_mem_access *m, srcu_read_unlock(&kvm->srcu, idx); } -static int kvmi_set_gfn_access(struct kvm *kvm, gfn_t gfn, u8 access) +static int kvmi_set_gfn_access(struct kvm *kvm, gfn_t gfn, u8 access, + u16 view) { struct kvmi_mem_access *m; bool used = false; @@ -1131,7 +1138,7 @@ static int kvmi_set_gfn_access(struct kvm *kvm, gfn_t gfn, u8 access) if (radix_tree_preload(GFP_KERNEL)) err = -KVM_ENOMEM; else - kvmi_set_mem_access(kvm, m, &used); + kvmi_set_mem_access(kvm, m, view, &used); radix_tree_preload_end(); @@ -1153,7 +1160,7 @@ static bool kvmi_is_visible_gfn(struct kvm *kvm, gfn_t gfn) return visible; } -static int set_page_access_entry(struct kvm_introspection *kvmi, +static int set_page_access_entry(struct kvm_introspection *kvmi, u16 view, const struct kvmi_page_access_entry *entry) { u8 unknown_bits = ~(KVMI_PAGE_ACCESS_R | KVMI_PAGE_ACCESS_W @@ -1169,7 +1176,7 @@ static int set_page_access_entry(struct kvm_introspection *kvmi, if (!kvmi_is_visible_gfn(kvm, gfn)) return entry->visible ? -KVM_EINVAL : 0; - return kvmi_set_gfn_access(kvm, gfn, entry->access); + return kvmi_set_gfn_access(kvm, gfn, entry->access, view); } int kvmi_cmd_set_page_access(struct kvm_introspection *kvmi, @@ -1187,7 +1194,7 @@ int kvmi_cmd_set_page_access(struct kvm_introspection *kvmi, return -KVM_EINVAL; for (; entry < end; entry++) { - int r = set_page_access_entry(kvmi, entry); + int r = set_page_access_entry(kvmi, 0, entry); if (r && !ec) ec = r; @@ -1197,12 +1204,12 @@ int kvmi_cmd_set_page_access(struct kvm_introspection *kvmi, } static int kvmi_get_gfn_access(struct kvm_introspection *kvmi, const gfn_t gfn, - u8 *access) + u8 *access, u16 view) { struct kvmi_mem_access *m; read_lock(&kvmi->access_tree_lock); - m = __kvmi_get_gfn_access(kvmi, gfn); + m = __kvmi_get_gfn_access(kvmi, gfn, view); if (m) *access = m->access; read_unlock(&kvmi->access_tree_lock); @@ -1211,12 +1218,13 @@ static int kvmi_get_gfn_access(struct kvm_introspection *kvmi, const gfn_t gfn, } bool kvmi_restricted_page_access(struct kvm_introspection *kvmi, gpa_t gpa, - u8 access) + u8 access, u16 view) { u8 allowed_access; int err; - err = kvmi_get_gfn_access(kvmi, gpa_to_gfn(gpa), &allowed_access); + err = kvmi_get_gfn_access(kvmi, gpa_to_gfn(gpa), &allowed_access, view); + if (err) return false; @@ -1264,10 +1272,14 @@ void kvmi_add_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, while (start < end) { struct kvmi_mem_access *m; + u16 view; - m = __kvmi_get_gfn_access(kvmi, start); - if (m) - kvmi_arch_update_page_tracking(kvm, slot, m); + for (view = 0; view < KVMI_MAX_ACCESS_TREES; view++) { + m = __kvmi_get_gfn_access(kvmi, start, view); + if (m) + kvmi_arch_update_page_tracking(kvm, slot, m, + view); + } start++; } @@ -1289,14 +1301,18 @@ void kvmi_remove_memslot(struct kvm *kvm, struct kvm_memory_slot *slot) while (start < end) { struct kvmi_mem_access *m; + u16 view; - m = __kvmi_get_gfn_access(kvmi, start); - if (m) { - u8 prev_access = m->access; + for (view = 0; view < KVMI_MAX_ACCESS_TREES; view++) { + m = __kvmi_get_gfn_access(kvmi, start, view); + if (m) { + u8 prev_access = m->access; - m->access = full_access; - kvmi_arch_update_page_tracking(kvm, slot, m); - m->access = prev_access; + m->access = full_access; + kvmi_arch_update_page_tracking(kvm, slot, m, + view); + m->access = prev_access; + } } start++; } @@ -1382,14 +1398,15 @@ void kvmi_singlestep_failed(struct kvm_vcpu *vcpu) } EXPORT_SYMBOL(kvmi_singlestep_failed); -static bool __kvmi_tracked_gfn(struct kvm_introspection *kvmi, gfn_t gfn) +static bool __kvmi_tracked_gfn(struct kvm_introspection *kvmi, gfn_t gfn, + u16 view) { u8 ignored_access; + int err; - if (kvmi_get_gfn_access(kvmi, gfn, &ignored_access)) - return false; + err = kvmi_get_gfn_access(kvmi, gfn, &ignored_access, view); - return true; + return !err; } bool kvmi_tracked_gfn(struct kvm_vcpu *vcpu, gfn_t gfn) @@ -1401,7 +1418,7 @@ bool kvmi_tracked_gfn(struct kvm_vcpu *vcpu, gfn_t gfn) if (!kvmi) return false; - ret = __kvmi_tracked_gfn(kvmi, gfn); + ret = __kvmi_tracked_gfn(kvmi, gfn, kvm_get_ept_view(vcpu)); kvmi_put(vcpu->kvm); diff --git a/virt/kvm/introspection/kvmi_int.h b/virt/kvm/introspection/kvmi_int.h index d78116442ddd..fc6dbd3a6472 100644 --- a/virt/kvm/introspection/kvmi_int.h +++ b/virt/kvm/introspection/kvmi_int.h @@ -89,7 +89,7 @@ int kvmi_cmd_set_page_access(struct kvm_introspection *kvmi, const struct kvmi_msg_hdr *msg, const struct kvmi_vm_set_page_access *req); bool kvmi_restricted_page_access(struct kvm_introspection *kvmi, gpa_t gpa, - u8 access); + u8 access, u16 view); bool kvmi_pf_event(struct kvm_vcpu *vcpu, gpa_t gpa, gva_t gva, u8 access); void kvmi_add_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, unsigned long npages); @@ -140,7 +140,7 @@ int kvmi_arch_cmd_vcpu_control_msr(struct kvm_vcpu *vcpu, const struct kvmi_vcpu_control_msr *req); void kvmi_arch_update_page_tracking(struct kvm *kvm, struct kvm_memory_slot *slot, - struct kvmi_mem_access *m); + struct kvmi_mem_access *m, u16 view); void kvmi_arch_hook(struct kvm *kvm); void kvmi_arch_unhook(struct kvm *kvm); void kvmi_arch_features(struct kvmi_features *feat);

[RFC,v1,17/34] KVM: introspection: extend the access rights database with EPT view info

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