From 1d487e9bf8ba66a7174c56a0029c54b1eca8f99c Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 11 Apr 2019 11:16:47 +0200 Subject: [PATCH] KVM: fix spectrev1 gadgets These were found with smatch, and then generalized when applicable. Signed-off-by: Paolo Bonzini --- arch/x86/kvm/lapic.c | 4 +++- include/linux/kvm_host.h | 10 ++++++---- virt/kvm/irqchip.c | 5 +++-- virt/kvm/kvm_main.c | 6 ++++-- 4 files changed, 16 insertions(+), 9 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 991fdf7fc17f..9bf70cf84564 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -138,6 +138,7 @@ static inline bool kvm_apic_map_get_logical_dest(struct kvm_apic_map *map, if (offset <= max_apic_id) { u8 cluster_size = min(max_apic_id - offset + 1, 16U); + offset = array_index_nospec(offset, map->max_apic_id + 1); *cluster = &map->phys_map[offset]; *mask = dest_id & (0xffff >> (16 - cluster_size)); } else { @@ -901,7 +902,8 @@ static inline bool kvm_apic_map_get_dest_lapic(struct kvm *kvm, if (irq->dest_id > map->max_apic_id) { *bitmap = 0; } else { - *dst = &map->phys_map[irq->dest_id]; + u32 dest_id = array_index_nospec(irq->dest_id, map->max_apic_id + 1); + *dst = &map->phys_map[dest_id]; *bitmap = 1; } return true; diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 9d55c63db09b..640a03642766 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -513,10 +514,10 @@ static inline struct kvm_io_bus *kvm_get_bus(struct kvm *kvm, enum kvm_bus idx) static inline struct kvm_vcpu *kvm_get_vcpu(struct kvm *kvm, int i) { - /* Pairs with smp_wmb() in kvm_vm_ioctl_create_vcpu, in case - * the caller has read kvm->online_vcpus before (as is the case - * for kvm_for_each_vcpu, for example). - */ + int num_vcpus = atomic_read(&kvm->online_vcpus); + i = array_index_nospec(i, num_vcpus); + + /* Pairs with smp_wmb() in kvm_vm_ioctl_create_vcpu. */ smp_rmb(); return kvm->vcpus[i]; } @@ -600,6 +601,7 @@ void kvm_put_kvm(struct kvm *kvm); static inline struct kvm_memslots *__kvm_memslots(struct kvm *kvm, int as_id) { + as_id = array_index_nospec(as_id, KVM_ADDRESS_SPACE_NUM); return srcu_dereference_check(kvm->memslots[as_id], &kvm->srcu, lockdep_is_held(&kvm->slots_lock) || !refcount_read(&kvm->users_count)); diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c index 3547b0d8c91e..79e59e4fa3dc 100644 --- a/virt/kvm/irqchip.c +++ b/virt/kvm/irqchip.c @@ -144,18 +144,19 @@ static int setup_routing_entry(struct kvm *kvm, { struct kvm_kernel_irq_routing_entry *ei; int r; + u32 gsi = array_index_nospec(ue->gsi, KVM_MAX_IRQ_ROUTES); /* * Do not allow GSI to be mapped to the same irqchip more than once. * Allow only one to one mapping between GSI and non-irqchip routing. */ - hlist_for_each_entry(ei, &rt->map[ue->gsi], link) + hlist_for_each_entry(ei, &rt->map[gsi], link) if (ei->type != KVM_IRQ_ROUTING_IRQCHIP || ue->type != KVM_IRQ_ROUTING_IRQCHIP || ue->u.irqchip.irqchip == ei->irqchip.irqchip) return -EINVAL; - e->gsi = ue->gsi; + e->gsi = gsi; e->type = ue->type; r = kvm_set_routing_entry(kvm, e, ue); if (r) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 55fe8e20d8fd..dc8edc97ba85 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2977,12 +2977,14 @@ static int kvm_ioctl_create_device(struct kvm *kvm, struct kvm_device_ops *ops = NULL; struct kvm_device *dev; bool test = cd->flags & KVM_CREATE_DEVICE_TEST; + int type; int ret; if (cd->type >= ARRAY_SIZE(kvm_device_ops_table)) return -ENODEV; - ops = kvm_device_ops_table[cd->type]; + type = array_index_nospec(cd->type, ARRAY_SIZE(kvm_device_ops_table)); + ops = kvm_device_ops_table[type]; if (ops == NULL) return -ENODEV; @@ -2997,7 +2999,7 @@ static int kvm_ioctl_create_device(struct kvm *kvm, dev->kvm = kvm; mutex_lock(&kvm->lock); - ret = ops->create(dev, cd->type); + ret = ops->create(dev, type); if (ret < 0) { mutex_unlock(&kvm->lock); kfree(dev); -- 2.30.2