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KVM: MMU: move audit to a separate file
Move the audit code from arch/x86/kvm/mmu.c to arch/x86/kvm/mmu_audit.c Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Xiao Guangrong
Avi Kivity
parent
8b1fe17cc7
commit
2f4f337248
2 changed files with 298 additions and 278 deletions
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@ -3490,282 +3490,5 @@ int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4])
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EXPORT_SYMBOL_GPL(kvm_mmu_get_spte_hierarchy);
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#ifdef CONFIG_KVM_MMU_AUDIT
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static const char *audit_msg;
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typedef void (*inspect_spte_fn) (struct kvm *kvm, u64 *sptep);
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static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp,
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inspect_spte_fn fn)
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{
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int i;
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for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
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u64 ent = sp->spt[i];
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if (is_shadow_present_pte(ent)) {
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if (!is_last_spte(ent, sp->role.level)) {
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struct kvm_mmu_page *child;
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child = page_header(ent & PT64_BASE_ADDR_MASK);
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__mmu_spte_walk(kvm, child, fn);
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} else
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fn(kvm, &sp->spt[i]);
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}
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}
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}
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static void mmu_spte_walk(struct kvm_vcpu *vcpu, inspect_spte_fn fn)
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{
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int i;
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struct kvm_mmu_page *sp;
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if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
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return;
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if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
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hpa_t root = vcpu->arch.mmu.root_hpa;
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sp = page_header(root);
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__mmu_spte_walk(vcpu->kvm, sp, fn);
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return;
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}
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for (i = 0; i < 4; ++i) {
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hpa_t root = vcpu->arch.mmu.pae_root[i];
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if (root && VALID_PAGE(root)) {
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root &= PT64_BASE_ADDR_MASK;
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sp = page_header(root);
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__mmu_spte_walk(vcpu->kvm, sp, fn);
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}
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}
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return;
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}
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static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte,
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gva_t va, int level)
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{
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u64 *pt = __va(page_pte & PT64_BASE_ADDR_MASK);
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int i;
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gva_t va_delta = 1ul << (PAGE_SHIFT + 9 * (level - 1));
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for (i = 0; i < PT64_ENT_PER_PAGE; ++i, va += va_delta) {
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u64 *sptep = pt + i;
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struct kvm_mmu_page *sp;
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gfn_t gfn;
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pfn_t pfn;
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hpa_t hpa;
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sp = page_header(__pa(sptep));
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if (sp->unsync) {
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if (level != PT_PAGE_TABLE_LEVEL) {
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printk(KERN_ERR "audit: (%s) error: unsync sp: %p level = %d\n",
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audit_msg, sp, level);
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return;
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}
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if (*sptep == shadow_notrap_nonpresent_pte) {
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printk(KERN_ERR "audit: (%s) error: notrap spte in unsync sp: %p\n",
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audit_msg, sp);
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return;
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}
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}
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if (sp->role.direct && *sptep == shadow_notrap_nonpresent_pte) {
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printk(KERN_ERR "audit: (%s) error: notrap spte in direct sp: %p\n",
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audit_msg, sp);
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return;
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}
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if (!is_shadow_present_pte(*sptep) ||
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!is_last_spte(*sptep, level))
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return;
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gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt);
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pfn = gfn_to_pfn_atomic(vcpu->kvm, gfn);
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if (is_error_pfn(pfn)) {
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kvm_release_pfn_clean(pfn);
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return;
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}
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hpa = pfn << PAGE_SHIFT;
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if ((*sptep & PT64_BASE_ADDR_MASK) != hpa)
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printk(KERN_ERR "xx audit error: (%s) levels %d"
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" gva %lx pfn %llx hpa %llx ent %llxn",
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audit_msg, vcpu->arch.mmu.root_level,
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va, pfn, hpa, *sptep);
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}
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}
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static void audit_mappings(struct kvm_vcpu *vcpu)
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{
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unsigned i;
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if (vcpu->arch.mmu.root_level == 4)
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audit_mappings_page(vcpu, vcpu->arch.mmu.root_hpa, 0, 4);
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else
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for (i = 0; i < 4; ++i)
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if (vcpu->arch.mmu.pae_root[i] & PT_PRESENT_MASK)
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audit_mappings_page(vcpu,
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vcpu->arch.mmu.pae_root[i],
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i << 30,
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2);
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}
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void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep)
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{
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unsigned long *rmapp;
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struct kvm_mmu_page *rev_sp;
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gfn_t gfn;
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rev_sp = page_header(__pa(sptep));
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gfn = kvm_mmu_page_get_gfn(rev_sp, sptep - rev_sp->spt);
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if (!gfn_to_memslot(kvm, gfn)) {
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if (!printk_ratelimit())
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return;
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printk(KERN_ERR "%s: no memslot for gfn %llx\n",
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audit_msg, gfn);
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printk(KERN_ERR "%s: index %ld of sp (gfn=%llx)\n",
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audit_msg, (long int)(sptep - rev_sp->spt),
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rev_sp->gfn);
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dump_stack();
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return;
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}
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rmapp = gfn_to_rmap(kvm, gfn, rev_sp->role.level);
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if (!*rmapp) {
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if (!printk_ratelimit())
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return;
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printk(KERN_ERR "%s: no rmap for writable spte %llx\n",
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audit_msg, *sptep);
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dump_stack();
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}
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}
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void audit_sptes_have_rmaps(struct kvm_vcpu *vcpu)
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{
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mmu_spte_walk(vcpu, inspect_spte_has_rmap);
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}
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static void check_mappings_rmap(struct kvm_vcpu *vcpu)
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{
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struct kvm_mmu_page *sp;
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int i;
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list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) {
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u64 *pt = sp->spt;
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if (sp->role.level != PT_PAGE_TABLE_LEVEL)
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continue;
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for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
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if (!is_rmap_spte(pt[i]))
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continue;
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inspect_spte_has_rmap(vcpu->kvm, &pt[i]);
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}
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}
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return;
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}
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static void audit_rmap(struct kvm_vcpu *vcpu)
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{
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check_mappings_rmap(vcpu);
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}
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static void audit_write_protection(struct kvm_vcpu *vcpu)
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{
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struct kvm_mmu_page *sp;
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struct kvm_memory_slot *slot;
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unsigned long *rmapp;
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u64 *spte;
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list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) {
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if (sp->role.direct)
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continue;
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if (sp->unsync)
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continue;
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if (sp->role.invalid)
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continue;
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slot = gfn_to_memslot(vcpu->kvm, sp->gfn);
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rmapp = &slot->rmap[sp->gfn - slot->base_gfn];
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spte = rmap_next(vcpu->kvm, rmapp, NULL);
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while (spte) {
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if (is_writable_pte(*spte))
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printk(KERN_ERR "%s: (%s) shadow page has "
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"writable mappings: gfn %llx role %x\n",
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__func__, audit_msg, sp->gfn,
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sp->role.word);
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spte = rmap_next(vcpu->kvm, rmapp, spte);
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}
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}
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}
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static void kvm_mmu_audit(void *ignore, struct kvm_vcpu *vcpu, int audit_point)
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{
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audit_msg = audit_point_name[audit_point];
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audit_rmap(vcpu);
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audit_write_protection(vcpu);
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if (strcmp("pre pte write", audit_msg) != 0)
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audit_mappings(vcpu);
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audit_sptes_have_rmaps(vcpu);
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}
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static bool mmu_audit;
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static void mmu_audit_enable(void)
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{
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int ret;
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if (mmu_audit)
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return;
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ret = register_trace_kvm_mmu_audit(kvm_mmu_audit, NULL);
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WARN_ON(ret);
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mmu_audit = true;
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}
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static void mmu_audit_disable(void)
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{
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if (!mmu_audit)
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return;
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unregister_trace_kvm_mmu_audit(kvm_mmu_audit, NULL);
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tracepoint_synchronize_unregister();
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mmu_audit = false;
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}
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static int mmu_audit_set(const char *val, const struct kernel_param *kp)
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{
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int ret;
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unsigned long enable;
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ret = strict_strtoul(val, 10, &enable);
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if (ret < 0)
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return -EINVAL;
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switch (enable) {
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case 0:
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mmu_audit_disable();
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break;
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case 1:
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mmu_audit_enable();
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break;
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default:
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return -EINVAL;
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}
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return 0;
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}
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static struct kernel_param_ops audit_param_ops = {
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.set = mmu_audit_set,
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.get = param_get_bool,
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};
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module_param_cb(mmu_audit, &audit_param_ops, &mmu_audit, 0644);
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#include "mmu_audit.c"
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#endif
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297
arch/x86/kvm/mmu_audit.c
Normal file
297
arch/x86/kvm/mmu_audit.c
Normal file
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@ -0,0 +1,297 @@
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/*
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* mmu_audit.c:
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*
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* Audit code for KVM MMU
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*
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* Copyright (C) 2006 Qumranet, Inc.
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* Copyright 2010 Red Hat, Inc. and/or its affilates.
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*
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* Authors:
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* Yaniv Kamay <yaniv@qumranet.com>
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* Avi Kivity <avi@qumranet.com>
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* Marcelo Tosatti <mtosatti@redhat.com>
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* Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
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*
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* This work is licensed under the terms of the GNU GPL, version 2. See
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* the COPYING file in the top-level directory.
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*
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*/
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static const char *audit_msg;
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typedef void (*inspect_spte_fn) (struct kvm *kvm, u64 *sptep);
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static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp,
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inspect_spte_fn fn)
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{
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int i;
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for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
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u64 ent = sp->spt[i];
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if (is_shadow_present_pte(ent)) {
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if (!is_last_spte(ent, sp->role.level)) {
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struct kvm_mmu_page *child;
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child = page_header(ent & PT64_BASE_ADDR_MASK);
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__mmu_spte_walk(kvm, child, fn);
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} else
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fn(kvm, &sp->spt[i]);
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}
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}
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}
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static void mmu_spte_walk(struct kvm_vcpu *vcpu, inspect_spte_fn fn)
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{
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int i;
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struct kvm_mmu_page *sp;
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if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
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return;
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if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
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hpa_t root = vcpu->arch.mmu.root_hpa;
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sp = page_header(root);
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__mmu_spte_walk(vcpu->kvm, sp, fn);
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return;
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}
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for (i = 0; i < 4; ++i) {
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hpa_t root = vcpu->arch.mmu.pae_root[i];
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if (root && VALID_PAGE(root)) {
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root &= PT64_BASE_ADDR_MASK;
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sp = page_header(root);
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__mmu_spte_walk(vcpu->kvm, sp, fn);
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}
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}
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return;
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}
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static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte,
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gva_t va, int level)
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{
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u64 *pt = __va(page_pte & PT64_BASE_ADDR_MASK);
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int i;
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gva_t va_delta = 1ul << (PAGE_SHIFT + 9 * (level - 1));
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for (i = 0; i < PT64_ENT_PER_PAGE; ++i, va += va_delta) {
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u64 *sptep = pt + i;
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struct kvm_mmu_page *sp;
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gfn_t gfn;
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pfn_t pfn;
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hpa_t hpa;
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sp = page_header(__pa(sptep));
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if (sp->unsync) {
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if (level != PT_PAGE_TABLE_LEVEL) {
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printk(KERN_ERR "audit: (%s) error: unsync sp: %p level = %d\n",
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audit_msg, sp, level);
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return;
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}
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if (*sptep == shadow_notrap_nonpresent_pte) {
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printk(KERN_ERR "audit: (%s) error: notrap spte in unsync sp: %p\n",
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audit_msg, sp);
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return;
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}
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}
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if (sp->role.direct && *sptep == shadow_notrap_nonpresent_pte) {
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printk(KERN_ERR "audit: (%s) error: notrap spte in direct sp: %p\n",
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audit_msg, sp);
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return;
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}
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if (!is_shadow_present_pte(*sptep) ||
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!is_last_spte(*sptep, level))
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return;
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gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt);
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pfn = gfn_to_pfn_atomic(vcpu->kvm, gfn);
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if (is_error_pfn(pfn)) {
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kvm_release_pfn_clean(pfn);
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return;
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}
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hpa = pfn << PAGE_SHIFT;
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if ((*sptep & PT64_BASE_ADDR_MASK) != hpa)
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printk(KERN_ERR "xx audit error: (%s) levels %d"
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" gva %lx pfn %llx hpa %llx ent %llxn",
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audit_msg, vcpu->arch.mmu.root_level,
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va, pfn, hpa, *sptep);
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}
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}
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static void audit_mappings(struct kvm_vcpu *vcpu)
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{
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unsigned i;
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if (vcpu->arch.mmu.root_level == 4)
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audit_mappings_page(vcpu, vcpu->arch.mmu.root_hpa, 0, 4);
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else
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for (i = 0; i < 4; ++i)
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if (vcpu->arch.mmu.pae_root[i] & PT_PRESENT_MASK)
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audit_mappings_page(vcpu,
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vcpu->arch.mmu.pae_root[i],
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i << 30,
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2);
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}
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void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep)
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{
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unsigned long *rmapp;
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struct kvm_mmu_page *rev_sp;
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gfn_t gfn;
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rev_sp = page_header(__pa(sptep));
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gfn = kvm_mmu_page_get_gfn(rev_sp, sptep - rev_sp->spt);
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if (!gfn_to_memslot(kvm, gfn)) {
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if (!printk_ratelimit())
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return;
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printk(KERN_ERR "%s: no memslot for gfn %llx\n",
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audit_msg, gfn);
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printk(KERN_ERR "%s: index %ld of sp (gfn=%llx)\n",
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audit_msg, (long int)(sptep - rev_sp->spt),
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rev_sp->gfn);
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dump_stack();
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return;
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}
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rmapp = gfn_to_rmap(kvm, gfn, rev_sp->role.level);
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if (!*rmapp) {
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if (!printk_ratelimit())
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return;
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printk(KERN_ERR "%s: no rmap for writable spte %llx\n",
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audit_msg, *sptep);
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dump_stack();
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}
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||||
}
|
||||
|
||||
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);
|
||||
Loading…
Reference in a new issue