[v2,2/5] KVM: MMU: move audit to a separate file

Message ID	4C7B86CA.9020507@cn.fujitsu.com (mailing list archive)
State	New, archived
Headers	show Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id o7UAGBOo002847 for <patchwork-kvm@patchwork.kernel.org>; Mon, 30 Aug 2010 10:21:31 GMT Message-ID: <4C7B86CA.9020507@cn.fujitsu.com> Date: Mon, 30 Aug 2010 18:24:10 +0800 From: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.11) Gecko/20100713 Thunderbird/3.0.6 MIME-Version: 1.0 To: Avi Kivity <avi@redhat.com> CC: Marcelo Tosatti <mtosatti@redhat.com>, LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org> Subject: [PATCH v2 2/5] KVM: MMU: move audit to a separate file References: <4C78FA00.8090606@cn.fujitsu.com> <4C7B867D.9080500@cn.fujitsu.com> In-Reply-To: <4C7B867D.9080500@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: kvm-owner@vger.kernel.org Precedence: bulk

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 8b750ff..d2dad65 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3490,282 +3490,5 @@ int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]) EXPORT_SYMBOL_GPL(kvm_mmu_get_spte_hierarchy); #ifdef CONFIG_KVM_MMU_AUDIT -static const char *audit_msg; - -typedef void (*inspect_spte_fn) (struct kvm *kvm, u64 *sptep); - -static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp, - inspect_spte_fn fn) -{ - int i; - - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { - u64 ent = sp->spt[i]; - - if (is_shadow_present_pte(ent)) { - if (!is_last_spte(ent, sp->role.level)) { - struct kvm_mmu_page *child; - child = page_header(ent & PT64_BASE_ADDR_MASK); - __mmu_spte_walk(kvm, child, fn); - } else - fn(kvm, &sp->spt[i]); - } - } -} - -static void mmu_spte_walk(struct kvm_vcpu *vcpu, inspect_spte_fn fn) -{ - int i; - struct kvm_mmu_page *sp; - - if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) - return; - if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { - hpa_t root = vcpu->arch.mmu.root_hpa; - sp = page_header(root); - __mmu_spte_walk(vcpu->kvm, sp, fn); - return; - } - for (i = 0; i < 4; ++i) { - hpa_t root = vcpu->arch.mmu.pae_root[i]; - - if (root && VALID_PAGE(root)) { - root &= PT64_BASE_ADDR_MASK; - sp = page_header(root); - __mmu_spte_walk(vcpu->kvm, sp, fn); - } - } - return; -} - -static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte, - gva_t va, int level) -{ - u64 *pt = __va(page_pte & PT64_BASE_ADDR_MASK); - int i; - gva_t va_delta = 1ul << (PAGE_SHIFT + 9 * (level - 1)); - - for (i = 0; i < PT64_ENT_PER_PAGE; ++i, va += va_delta) { - u64 *sptep = pt + i; - struct kvm_mmu_page *sp; - gfn_t gfn; - pfn_t pfn; - hpa_t hpa; - - sp = page_header(__pa(sptep)); - - if (sp->unsync) { - if (level != PT_PAGE_TABLE_LEVEL) { - printk(KERN_ERR "audit: (%s) error: unsync sp: %p level = %d\n", - audit_msg, sp, level); - return; - } - - if (*sptep == shadow_notrap_nonpresent_pte) { - printk(KERN_ERR "audit: (%s) error: notrap spte in unsync sp: %p\n", - audit_msg, sp); - return; - } - } - - if (sp->role.direct && *sptep == shadow_notrap_nonpresent_pte) { - printk(KERN_ERR "audit: (%s) error: notrap spte in direct sp: %p\n", - audit_msg, sp); - return; - } - - if (!is_shadow_present_pte(*sptep) || - !is_last_spte(*sptep, level)) - return; - - gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt); - pfn = gfn_to_pfn_atomic(vcpu->kvm, gfn); - - if (is_error_pfn(pfn)) { - kvm_release_pfn_clean(pfn); - return; - } - - hpa = pfn << PAGE_SHIFT; - - if ((*sptep & PT64_BASE_ADDR_MASK) != hpa) - printk(KERN_ERR "xx audit error: (%s) levels %d" - " gva %lx pfn %llx hpa %llx ent %llxn", - audit_msg, vcpu->arch.mmu.root_level, - va, pfn, hpa, *sptep); - } -} - -static void audit_mappings(struct kvm_vcpu *vcpu) -{ - unsigned i; - - if (vcpu->arch.mmu.root_level == 4) - audit_mappings_page(vcpu, vcpu->arch.mmu.root_hpa, 0, 4); - else - for (i = 0; i < 4; ++i) - if (vcpu->arch.mmu.pae_root[i] & PT_PRESENT_MASK) - audit_mappings_page(vcpu, - vcpu->arch.mmu.pae_root[i], - i << 30, - 2); -} - -void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep) -{ - unsigned long *rmapp; - struct kvm_mmu_page *rev_sp; - gfn_t gfn; - - - rev_sp = page_header(__pa(sptep)); - gfn = kvm_mmu_page_get_gfn(rev_sp, sptep - rev_sp->spt); - - if (!gfn_to_memslot(kvm, gfn)) { - if (!printk_ratelimit()) - return; - printk(KERN_ERR "%s: no memslot for gfn %llx\n", - audit_msg, gfn); - printk(KERN_ERR "%s: index %ld of sp (gfn=%llx)\n", - audit_msg, (long int)(sptep - rev_sp->spt), - rev_sp->gfn); - dump_stack(); - return; - } - - rmapp = gfn_to_rmap(kvm, gfn, rev_sp->role.level); - if (!*rmapp) { - if (!printk_ratelimit()) - return; - printk(KERN_ERR "%s: no rmap for writable spte %llx\n", - audit_msg, *sptep); - dump_stack(); - } -} - -void audit_sptes_have_rmaps(struct kvm_vcpu *vcpu) -{ - mmu_spte_walk(vcpu, inspect_spte_has_rmap); -} - -static void check_mappings_rmap(struct kvm_vcpu *vcpu) -{ - struct kvm_mmu_page *sp; - int i; - - list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { - u64 *pt = sp->spt; - - if (sp->role.level != PT_PAGE_TABLE_LEVEL) - continue; - - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { - if (!is_rmap_spte(pt[i])) - continue; - - inspect_spte_has_rmap(vcpu->kvm, &pt[i]); - } - } - return; -}--- arch/x86/kvm/mmu.c | 279 +------------------------------------------- arch/x86/kvm/mmu_audit.c | 297 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 298 insertions(+), 278 deletions(-) create mode 100644 arch/x86/kvm/mmu_audit.c diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 8b750ff..d2dad65 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3490,282 +3490,5 @@ int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]) EXPORT_SYMBOL_GPL(kvm_mmu_get_spte_hierarchy); #ifdef CONFIG_KVM_MMU_AUDIT -static const char *audit_msg; - -typedef void (*inspect_spte_fn) (struct kvm *kvm, u64 *sptep); - -static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp, - inspect_spte_fn fn) -{ - int i; - - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { - u64 ent = sp->spt[i]; - - if (is_shadow_present_pte(ent)) { - if (!is_last_spte(ent, sp->role.level)) { - struct kvm_mmu_page *child; - child = page_header(ent & PT64_BASE_ADDR_MASK); - __mmu_spte_walk(kvm, child, fn); - } else - fn(kvm, &sp->spt[i]); - } - } -} - -static void mmu_spte_walk(struct kvm_vcpu *vcpu, inspect_spte_fn fn) -{ - int i; - struct kvm_mmu_page *sp; - - if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) - return; - if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { - hpa_t root = vcpu->arch.mmu.root_hpa; - sp = page_header(root); - __mmu_spte_walk(vcpu->kvm, sp, fn); - return; - } - for (i = 0; i < 4; ++i) { - hpa_t root = vcpu->arch.mmu.pae_root[i]; - - if (root && VALID_PAGE(root)) { - root &= PT64_BASE_ADDR_MASK; - sp = page_header(root); - __mmu_spte_walk(vcpu->kvm, sp, fn); - } - } - return; -} - -static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte, - gva_t va, int level) -{ - u64 *pt = __va(page_pte & PT64_BASE_ADDR_MASK); - int i; - gva_t va_delta = 1ul << (PAGE_SHIFT + 9 * (level - 1)); - - for (i = 0; i < PT64_ENT_PER_PAGE; ++i, va += va_delta) { - u64 *sptep = pt + i; - struct kvm_mmu_page *sp; - gfn_t gfn; - pfn_t pfn; - hpa_t hpa; - - sp = page_header(__pa(sptep)); - - if (sp->unsync) { - if (level != PT_PAGE_TABLE_LEVEL) { - printk(KERN_ERR "audit: (%s) error: unsync sp: %p level = %d\n", - audit_msg, sp, level); - return; - } - - if (*sptep == shadow_notrap_nonpresent_pte) { - printk(KERN_ERR "audit: (%s) error: notrap spte in unsync sp: %p\n", - audit_msg, sp); - return; - } - } - - if (sp->role.direct && *sptep == shadow_notrap_nonpresent_pte) { - printk(KERN_ERR "audit: (%s) error: notrap spte in direct sp: %p\n", - audit_msg, sp); - return; - } - - if (!is_shadow_present_pte(*sptep) || - !is_last_spte(*sptep, level)) - return; - - gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt); - pfn = gfn_to_pfn_atomic(vcpu->kvm, gfn); - - if (is_error_pfn(pfn)) { - kvm_release_pfn_clean(pfn); - return; - } - - hpa = pfn << PAGE_SHIFT; - - if ((*sptep & PT64_BASE_ADDR_MASK) != hpa) - printk(KERN_ERR "xx audit error: (%s) levels %d" - " gva %lx pfn %llx hpa %llx ent %llxn", - audit_msg, vcpu->arch.mmu.root_level, - va, pfn, hpa, *sptep); - } -} - -static void audit_mappings(struct kvm_vcpu *vcpu) -{ - unsigned i; - - if (vcpu->arch.mmu.root_level == 4) - audit_mappings_page(vcpu, vcpu->arch.mmu.root_hpa, 0, 4); - else - for (i = 0; i < 4; ++i) - if (vcpu->arch.mmu.pae_root[i] & PT_PRESENT_MASK) - audit_mappings_page(vcpu, - vcpu->arch.mmu.pae_root[i], - i << 30, - 2); -} - -void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep) -{ - unsigned long *rmapp; - struct kvm_mmu_page *rev_sp; - gfn_t gfn; - - - rev_sp = page_header(__pa(sptep)); - gfn = kvm_mmu_page_get_gfn(rev_sp, sptep - rev_sp->spt); - - if (!gfn_to_memslot(kvm, gfn)) { - if (!printk_ratelimit()) - return; - printk(KERN_ERR "%s: no memslot for gfn %llx\n", - audit_msg, gfn); - printk(KERN_ERR "%s: index %ld of sp (gfn=%llx)\n", - audit_msg, (long int)(sptep - rev_sp->spt), - rev_sp->gfn); - dump_stack(); - return; - } - - rmapp = gfn_to_rmap(kvm, gfn, rev_sp->role.level); - if (!*rmapp) { - if (!printk_ratelimit()) - return; - printk(KERN_ERR "%s: no rmap for writable spte %llx\n", - audit_msg, *sptep); - dump_stack(); - } -} - -void audit_sptes_have_rmaps(struct kvm_vcpu *vcpu) -{ - mmu_spte_walk(vcpu, inspect_spte_has_rmap); -} - -static void check_mappings_rmap(struct kvm_vcpu *vcpu) -{ - struct kvm_mmu_page *sp; - int i; - - list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { - u64 *pt = sp->spt; - - if (sp->role.level != PT_PAGE_TABLE_LEVEL) - continue; - - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { - if (!is_rmap_spte(pt[i])) - continue; - - inspect_spte_has_rmap(vcpu->kvm, &pt[i]); - } - } - return; -} - -static void audit_rmap(struct kvm_vcpu *vcpu) -{ - check_mappings_rmap(vcpu); -} - -static void audit_write_protection(struct kvm_vcpu *vcpu) -{ - struct kvm_mmu_page *sp; - struct kvm_memory_slot *slot; - unsigned long *rmapp; - u64 *spte; - - list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { - if (sp->role.direct) - continue; - if (sp->unsync) - continue; - if (sp->role.invalid) - continue; - - slot = gfn_to_memslot(vcpu->kvm, sp->gfn); - rmapp = &slot->rmap[sp->gfn - slot->base_gfn]; - - spte = rmap_next(vcpu->kvm, rmapp, NULL); - while (spte) { - if (is_writable_pte(*spte)) - printk(KERN_ERR "%s: (%s) shadow page has " - "writable mappings: gfn %llx role %x\n", - __func__, audit_msg, sp->gfn, - sp->role.word); - spte = rmap_next(vcpu->kvm, rmapp, spte); - } - } -} - -static void kvm_mmu_audit(void *ignore, struct kvm_vcpu *vcpu, int audit_point) -{ - audit_msg = audit_point_name[audit_point]; - audit_rmap(vcpu); - audit_write_protection(vcpu); - if (strcmp("pre pte write", audit_msg) != 0) - audit_mappings(vcpu); - audit_sptes_have_rmaps(vcpu); -} - -static bool mmu_audit; - -static void mmu_audit_enable(void) -{ - int ret; - - if (mmu_audit) - return; - - ret = register_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); - WARN_ON(ret); - - mmu_audit = true; -} - -static void mmu_audit_disable(void) -{ - if (!mmu_audit) - return; - - unregister_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); - tracepoint_synchronize_unregister(); - mmu_audit = false; -} - -static int mmu_audit_set(const char *val, const struct kernel_param *kp) -{ - int ret; - unsigned long enable; - - ret = strict_strtoul(val, 10, &enable); - if (ret < 0) - return -EINVAL; - - switch (enable) { - case 0: - mmu_audit_disable(); - break; - case 1: - mmu_audit_enable(); - break; - default: - return -EINVAL; - } - - return 0; -} - -static struct kernel_param_ops audit_param_ops = { - .set = mmu_audit_set, - .get = param_get_bool, -}; - -module_param_cb(mmu_audit, &audit_param_ops, &mmu_audit, 0644); +#include "mmu_audit.c" #endif diff --git a/arch/x86/kvm/mmu_audit.c b/arch/x86/kvm/mmu_audit.c new file mode 100644 index 0000000..fb8a461 --- /dev/null +++ b/arch/x86/kvm/mmu_audit.c @@ -0,0 +1,297 @@ +/* + * mmu_audit.c: + * + * Audit code for KVM MMU + * + * Copyright (C) 2006 Qumranet, Inc. + * Copyright 2010 Red Hat, Inc. and/or its affilates. + * + * Authors: + * Yaniv Kamay <yaniv@qumranet.com> + * Avi Kivity <avi@qumranet.com> + * Marcelo Tosatti <mtosatti@redhat.com> + * Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + */ + +static const char *audit_msg; + +typedef void (*inspect_spte_fn) (struct kvm *kvm, u64 *sptep); + +static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp, + inspect_spte_fn fn) +{ + int i; + + for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { + u64 ent = sp->spt[i]; + + if (is_shadow_present_pte(ent)) { + if (!is_last_spte(ent, sp->role.level)) { + struct kvm_mmu_page *child; + child = page_header(ent & PT64_BASE_ADDR_MASK); + __mmu_spte_walk(kvm, child, fn); + } else + fn(kvm, &sp->spt[i]); + } + } +} + +static void mmu_spte_walk(struct kvm_vcpu *vcpu, inspect_spte_fn fn) +{ + int i; + struct kvm_mmu_page *sp; + + if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) + return; + if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { + hpa_t root = vcpu->arch.mmu.root_hpa; + sp = page_header(root); + __mmu_spte_walk(vcpu->kvm, sp, fn); + return; + } + for (i = 0; i < 4; ++i) { + hpa_t root = vcpu->arch.mmu.pae_root[i]; + + if (root && VALID_PAGE(root)) { + root &= PT64_BASE_ADDR_MASK; + sp = page_header(root); + __mmu_spte_walk(vcpu->kvm, sp, fn); + } + } + return; +} + +static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte, + gva_t va, int level) +{ + u64 *pt = __va(page_pte & PT64_BASE_ADDR_MASK); + int i; + gva_t va_delta = 1ul << (PAGE_SHIFT + 9 * (level - 1)); + + for (i = 0; i < PT64_ENT_PER_PAGE; ++i, va += va_delta) { + u64 *sptep = pt + i; + struct kvm_mmu_page *sp; + gfn_t gfn; + pfn_t pfn; + hpa_t hpa; + + sp = page_header(__pa(sptep)); + + if (sp->unsync) { + if (level != PT_PAGE_TABLE_LEVEL) { + printk(KERN_ERR "audit: (%s) error: unsync sp: %p level = %d\n", + audit_msg, sp, level); + return; + } + + if (*sptep == shadow_notrap_nonpresent_pte) { + printk(KERN_ERR "audit: (%s) error: notrap spte in unsync sp: %p\n", + audit_msg, sp); + return; + } + } + + if (sp->role.direct && *sptep == shadow_notrap_nonpresent_pte) { + printk(KERN_ERR "audit: (%s) error: notrap spte in direct sp: %p\n", + audit_msg, sp); + return; + } + + if (!is_shadow_present_pte(*sptep) || + !is_last_spte(*sptep, level)) + return; + + gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt); + pfn = gfn_to_pfn_atomic(vcpu->kvm, gfn); + + if (is_error_pfn(pfn)) { + kvm_release_pfn_clean(pfn); + return; + } + + hpa = pfn << PAGE_SHIFT; + + if ((*sptep & PT64_BASE_ADDR_MASK) != hpa) + printk(KERN_ERR "xx audit error: (%s) levels %d" + " gva %lx pfn %llx hpa %llx ent %llxn", + audit_msg, vcpu->arch.mmu.root_level, + va, pfn, hpa, *sptep); + } +} + +static void audit_mappings(struct kvm_vcpu *vcpu) +{ + unsigned i; + + if (vcpu->arch.mmu.root_level == 4) + audit_mappings_page(vcpu, vcpu->arch.mmu.root_hpa, 0, 4); + else + for (i = 0; i < 4; ++i) + if (vcpu->arch.mmu.pae_root[i] & PT_PRESENT_MASK) + audit_mappings_page(vcpu, + vcpu->arch.mmu.pae_root[i], + i << 30, + 2); +} + +void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep) +{ + unsigned long *rmapp; + struct kvm_mmu_page *rev_sp; + gfn_t gfn; + + + rev_sp = page_header(__pa(sptep)); + gfn = kvm_mmu_page_get_gfn(rev_sp, sptep - rev_sp->spt); + + if (!gfn_to_memslot(kvm, gfn)) { + if (!printk_ratelimit()) + return; + printk(KERN_ERR "%s: no memslot for gfn %llx\n", + audit_msg, gfn); + printk(KERN_ERR "%s: index %ld of sp (gfn=%llx)\n", + audit_msg, (long int)(sptep - rev_sp->spt), + rev_sp->gfn); + dump_stack(); + return; + } + + rmapp = gfn_to_rmap(kvm, gfn, rev_sp->role.level); + if (!*rmapp) { + if (!printk_ratelimit()) + return; + printk(KERN_ERR "%s: no rmap for writable spte %llx\n", + audit_msg, *sptep); + dump_stack(); + } +} + +void audit_sptes_have_rmaps(struct kvm_vcpu *vcpu) +{ + mmu_spte_walk(vcpu, inspect_spte_has_rmap); +} + +static void check_mappings_rmap(struct kvm_vcpu *vcpu) +{ + struct kvm_mmu_page *sp; + int i; + + list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { + u64 *pt = sp->spt; + + if (sp->role.level != PT_PAGE_TABLE_LEVEL) + continue; + + for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { + if (!is_rmap_spte(pt[i])) + continue; + + inspect_spte_has_rmap(vcpu->kvm, &pt[i]); + } + } + return; +} + +static void audit_rmap(struct kvm_vcpu *vcpu) +{ + check_mappings_rmap(vcpu); +} + +static void audit_write_protection(struct kvm_vcpu *vcpu) +{ + struct kvm_mmu_page *sp; + struct kvm_memory_slot *slot; + unsigned long *rmapp; + u64 *spte; + + list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { + if (sp->role.direct) + continue; + if (sp->unsync) + continue; + if (sp->role.invalid) + continue; + + slot = gfn_to_memslot(vcpu->kvm, sp->gfn); + rmapp = &slot->rmap[sp->gfn - slot->base_gfn]; + + spte = rmap_next(vcpu->kvm, rmapp, NULL); + while (spte) { + if (is_writable_pte(*spte)) + printk(KERN_ERR "%s: (%s) shadow page has " + "writable mappings: gfn %llx role %x\n", + __func__, audit_msg, sp->gfn, + sp->role.word); + spte = rmap_next(vcpu->kvm, rmapp, spte); + } + } +} + +static void kvm_mmu_audit(void *ignore, struct kvm_vcpu *vcpu, int audit_point) +{ + audit_msg = audit_point_name[audit_point]; + audit_rmap(vcpu); + audit_write_protection(vcpu); + if (strcmp("pre pte write", audit_msg) != 0) + audit_mappings(vcpu); + audit_sptes_have_rmaps(vcpu); +} + +static bool mmu_audit; + +static void mmu_audit_enable(void) +{ + int ret; + + if (mmu_audit) + return; + + ret = register_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); + WARN_ON(ret); + + mmu_audit = true; +} + +static void mmu_audit_disable(void) +{ + if (!mmu_audit) + return; + + unregister_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); + tracepoint_synchronize_unregister(); + mmu_audit = false; +} + +static int mmu_audit_set(const char *val, const struct kernel_param *kp) +{ + int ret; + unsigned long enable; + + ret = strict_strtoul(val, 10, &enable); + if (ret < 0) + return -EINVAL; + + switch (enable) { + case 0: + mmu_audit_disable(); + break; + case 1: + mmu_audit_enable(); + break; + default: + return -EINVAL; + } + + return 0; +} + +static struct kernel_param_ops audit_param_ops = { + .set = mmu_audit_set, + .get = param_get_bool, +}; + +module_param_cb(mmu_audit, &audit_param_ops, &mmu_audit, 0644); -- 1.7.0.4 - -static void audit_rmap(struct kvm_vcpu *vcpu) -{ - check_mappings_rmap(vcpu); -} - -static void audit_write_protection(struct kvm_vcpu *vcpu) -{ - struct kvm_mmu_page *sp; - struct kvm_memory_slot *slot; - unsigned long *rmapp; - u64 *spte; - - list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { - if (sp->role.direct) - continue; - if (sp->unsync) - continue; - if (sp->role.invalid) - continue; - - slot = gfn_to_memslot(vcpu->kvm, sp->gfn); - rmapp = &slot->rmap[sp->gfn - slot->base_gfn]; - - spte = rmap_next(vcpu->kvm, rmapp, NULL); - while (spte) { - if (is_writable_pte(*spte)) - printk(KERN_ERR "%s: (%s) shadow page has " - "writable mappings: gfn %llx role %x\n", - __func__, audit_msg, sp->gfn, - sp->role.word); - spte = rmap_next(vcpu->kvm, rmapp, spte); - } - } -} - -static void kvm_mmu_audit(void *ignore, struct kvm_vcpu *vcpu, int audit_point) -{ - audit_msg = audit_point_name[audit_point]; - audit_rmap(vcpu); - audit_write_protection(vcpu); - if (strcmp("pre pte write", audit_msg) != 0) - audit_mappings(vcpu); - audit_sptes_have_rmaps(vcpu); -} - -static bool mmu_audit; - -static void mmu_audit_enable(void) -{ - int ret; - - if (mmu_audit) - return; - - ret = register_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); - WARN_ON(ret); - - mmu_audit = true; -} - -static void mmu_audit_disable(void) -{ - if (!mmu_audit) - return; - - unregister_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); - tracepoint_synchronize_unregister(); - mmu_audit = false; -} - -static int mmu_audit_set(const char *val, const struct kernel_param *kp) -{ - int ret; - unsigned long enable; - - ret = strict_strtoul(val, 10, &enable); - if (ret < 0) - return -EINVAL; - - switch (enable) { - case 0: - mmu_audit_disable(); - break; - case 1: - mmu_audit_enable(); - break; - default: - return -EINVAL; - } - - return 0; -} - -static struct kernel_param_ops audit_param_ops = { - .set = mmu_audit_set, - .get = param_get_bool, -}; - -module_param_cb(mmu_audit, &audit_param_ops, &mmu_audit, 0644); +#include "mmu_audit.c" #endif diff --git a/arch/x86/kvm/mmu_audit.c b/arch/x86/kvm/mmu_audit.c new file mode 100644 index 0000000..fb8a461 --- /dev/null +++ b/arch/x86/kvm/mmu_audit.c @@ -0,0 +1,297 @@ +/* + * mmu_audit.c: + * + * Audit code for KVM MMU + * + * Copyright (C) 2006 Qumranet, Inc. + * Copyright 2010 Red Hat, Inc. and/or its affilates. + * + * Authors: + * Yaniv Kamay <yaniv@qumranet.com> + * Avi Kivity <avi@qumranet.com> + * Marcelo Tosatti <mtosatti@redhat.com> + * Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + */ + +static const char *audit_msg; + +typedef void (*inspect_spte_fn) (struct kvm *kvm, u64 *sptep); + +static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp, + inspect_spte_fn fn) +{ + int i; + + for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { + u64 ent = sp->spt[i]; + + if (is_shadow_present_pte(ent)) { + if (!is_last_spte(ent, sp->role.level)) { + struct kvm_mmu_page *child; + child = page_header(ent & PT64_BASE_ADDR_MASK); + __mmu_spte_walk(kvm, child, fn); + } else + fn(kvm, &sp->spt[i]); + } + } +} + +static void mmu_spte_walk(struct kvm_vcpu *vcpu, inspect_spte_fn fn) +{ + int i; + struct kvm_mmu_page *sp; + + if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) + return; + if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { + hpa_t root = vcpu->arch.mmu.root_hpa; + sp = page_header(root); + __mmu_spte_walk(vcpu->kvm, sp, fn); + return; + } + for (i = 0; i < 4; ++i) { + hpa_t root = vcpu->arch.mmu.pae_root[i]; + + if (root && VALID_PAGE(root)) { + root &= PT64_BASE_ADDR_MASK; + sp = page_header(root); + __mmu_spte_walk(vcpu->kvm, sp, fn); + } + } + return; +} + +static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte, + gva_t va, int level) +{ + u64 *pt = __va(page_pte & PT64_BASE_ADDR_MASK); + int i; + gva_t va_delta = 1ul << (PAGE_SHIFT + 9 * (level - 1)); + + for (i = 0; i < PT64_ENT_PER_PAGE; ++i, va += va_delta) { + u64 *sptep = pt + i; + struct kvm_mmu_page *sp; + gfn_t gfn; + pfn_t pfn; + hpa_t hpa; + + sp = page_header(__pa(sptep)); + + if (sp->unsync) { + if (level != PT_PAGE_TABLE_LEVEL) { + printk(KERN_ERR "audit: (%s) error: unsync sp: %p level = %d\n", + audit_msg, sp, level); + return; + } + + if (*sptep == shadow_notrap_nonpresent_pte) { + printk(KERN_ERR "audit: (%s) error: notrap spte in unsync sp: %p\n", + audit_msg, sp); + return; + } + } + + if (sp->role.direct && *sptep == shadow_notrap_nonpresent_pte) { + printk(KERN_ERR "audit: (%s) error: notrap spte in direct sp: %p\n", + audit_msg, sp); + return; + } + + if (!is_shadow_present_pte(*sptep) || + !is_last_spte(*sptep, level)) + return; + + gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt); + pfn = gfn_to_pfn_atomic(vcpu->kvm, gfn); + + if (is_error_pfn(pfn)) { + kvm_release_pfn_clean(pfn); + return; + } + + hpa = pfn << PAGE_SHIFT; + + if ((*sptep & PT64_BASE_ADDR_MASK) != hpa) + printk(KERN_ERR "xx audit error: (%s) levels %d" + " gva %lx pfn %llx hpa %llx ent %llxn", + audit_msg, vcpu->arch.mmu.root_level, + va, pfn, hpa, *sptep); + } +} + +static void audit_mappings(struct kvm_vcpu *vcpu) +{ + unsigned i; + + if (vcpu->arch.mmu.root_level == 4) + audit_mappings_page(vcpu, vcpu->arch.mmu.root_hpa, 0, 4); + else + for (i = 0; i < 4; ++i) + if (vcpu->arch.mmu.pae_root[i] & PT_PRESENT_MASK) + audit_mappings_page(vcpu, + vcpu->arch.mmu.pae_root[i], + i << 30, + 2); +} + +void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep) +{ + unsigned long *rmapp; + struct kvm_mmu_page *rev_sp; + gfn_t gfn; + + + rev_sp = page_header(__pa(sptep)); + gfn = kvm_mmu_page_get_gfn(rev_sp, sptep - rev_sp->spt); + + if (!gfn_to_memslot(kvm, gfn)) { + if (!printk_ratelimit()) + return; + printk(KERN_ERR "%s: no memslot for gfn %llx\n", + audit_msg, gfn); + printk(KERN_ERR "%s: index %ld of sp (gfn=%llx)\n", + audit_msg, (long int)(sptep - rev_sp->spt), + rev_sp->gfn); + dump_stack(); + return; + } + + rmapp = gfn_to_rmap(kvm, gfn, rev_sp->role.level); + if (!*rmapp) { + if (!printk_ratelimit()) + return; + printk(KERN_ERR "%s: no rmap for writable spte %llx\n", + audit_msg, *sptep); + dump_stack(); + } +} + +void audit_sptes_have_rmaps(struct kvm_vcpu *vcpu) +{ + mmu_spte_walk(vcpu, inspect_spte_has_rmap); +} + +static void check_mappings_rmap(struct kvm_vcpu *vcpu) +{ + struct kvm_mmu_page *sp; + int i; + + list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { + u64 *pt = sp->spt; + + if (sp->role.level != PT_PAGE_TABLE_LEVEL) + continue; + + for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { + if (!is_rmap_spte(pt[i])) + continue; + + inspect_spte_has_rmap(vcpu->kvm, &pt[i]); + } + } + return; +} + +static void audit_rmap(struct kvm_vcpu *vcpu) +{ + check_mappings_rmap(vcpu); +} + +static void audit_write_protection(struct kvm_vcpu *vcpu) +{ + struct kvm_mmu_page *sp; + struct kvm_memory_slot *slot; + unsigned long *rmapp; + u64 *spte; + + list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { + if (sp->role.direct) + continue; + if (sp->unsync) + continue; + if (sp->role.invalid) + continue; + + slot = gfn_to_memslot(vcpu->kvm, sp->gfn); + rmapp = &slot->rmap[sp->gfn - slot->base_gfn]; + + spte = rmap_next(vcpu->kvm, rmapp, NULL); + while (spte) { + if (is_writable_pte(*spte)) + printk(KERN_ERR "%s: (%s) shadow page has " + "writable mappings: gfn %llx role %x\n", + __func__, audit_msg, sp->gfn, + sp->role.word); + spte = rmap_next(vcpu->kvm, rmapp, spte); + } + } +} + +static void kvm_mmu_audit(void *ignore, struct kvm_vcpu *vcpu, int audit_point) +{ + audit_msg = audit_point_name[audit_point]; + audit_rmap(vcpu); + audit_write_protection(vcpu); + if (strcmp("pre pte write", audit_msg) != 0) + audit_mappings(vcpu); + audit_sptes_have_rmaps(vcpu); +} + +static bool mmu_audit; + +static void mmu_audit_enable(void) +{ + int ret; + + if (mmu_audit) + return; + + ret = register_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); + WARN_ON(ret); + + mmu_audit = true; +} + +static void mmu_audit_disable(void) +{ + if (!mmu_audit) + return; + + unregister_trace_kvm_mmu_audit(kvm_mmu_audit, NULL); + tracepoint_synchronize_unregister(); + mmu_audit = false; +} + +static int mmu_audit_set(const char *val, const struct kernel_param *kp) +{ + int ret; + unsigned long enable; + + ret = strict_strtoul(val, 10, &enable); + if (ret < 0) + return -EINVAL; + + switch (enable) { + case 0: + mmu_audit_disable(); + break; + case 1: + mmu_audit_enable(); + break; + default: + return -EINVAL; + } + + return 0; +} + +static struct kernel_param_ops audit_param_ops = { + .set = mmu_audit_set, + .get = param_get_bool, +}; + +module_param_cb(mmu_audit, &audit_param_ops, &mmu_audit, 0644);

[v2,2/5] KVM: MMU: move audit to a separate file

Commit Message

Patch