From: Sean Christopherson Date: Fri, 2 Jul 2021 15:04:23 -0700 Subject: KVM: Add infrastructure and macro to mark VM as bugged Git-commit: 0b8f11737cffc1a406d1134b58687abc29d76b52 Patch-mainline: v5.15-rc1 References: bsc#1200788 CVE-2022-2153 Signed-off-by: Sean Christopherson Signed-off-by: Isaku Yamahata Reviewed-by: Paolo Bonzini Message-Id: <3a0998645c328bf0895f1290e61821b70f048549.1625186503.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini Acked-by: Dario Faggioli --- include/linux/kvm_host.h | 28 +++++++++++++++++++++++++++- virt/kvm/kvm_main.c | 10 +++++----- 2 files changed, 32 insertions(+), 6 deletions(-) --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -128,6 +128,7 @@ #define KVM_REQ_MMU_RELOAD (1 | KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) #define KVM_REQ_PENDING_TIMER 2 #define KVM_REQ_UNHALT 3 +#define KVM_REQ_VM_BUGGED (4 | KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) #define KVM_REQUEST_ARCH_BASE 8 #define KVM_ARCH_REQ_FLAGS(nr, flags) ({ \ @@ -448,6 +449,7 @@ struct srcu_struct srcu; struct srcu_struct irq_srcu; pid_t userspace_pid; + bool vm_bugged; }; #define kvm_err(fmt, ...) \ @@ -476,6 +478,31 @@ #define vcpu_err(vcpu, fmt, ...) \ kvm_err("vcpu%i " fmt, (vcpu)->vcpu_id, ## __VA_ARGS__) +bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req); +static inline void kvm_vm_bugged(struct kvm *kvm) +{ + kvm->vm_bugged = true; + kvm_make_all_cpus_request(kvm, KVM_REQ_VM_BUGGED); +} + +#define KVM_BUG(cond, kvm, fmt...) \ +({ \ + int __ret = (cond); \ + \ + if (WARN_ONCE(__ret && !(kvm)->vm_bugged, fmt)) \ + kvm_vm_bugged(kvm); \ + unlikely(__ret); \ +}) + +#define KVM_BUG_ON(cond, kvm) \ +({ \ + int __ret = (cond); \ + \ + if (WARN_ON_ONCE(__ret && !(kvm)->vm_bugged)) \ + kvm_vm_bugged(kvm); \ + unlikely(__ret); \ +}) + static inline struct kvm_io_bus *kvm_get_bus(struct kvm *kvm, enum kvm_bus idx) { return srcu_dereference_check(kvm->buses[idx], &kvm->srcu, @@ -732,7 +732,6 @@ void kvm_reload_remote_mmus(struct kvm * bool kvm_make_vcpus_request_mask(struct kvm *kvm, unsigned int req, unsigned long *vcpu_bitmap, cpumask_var_t tmp); -bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req); long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg); --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2673,7 +2673,7 @@ struct kvm_fpu *fpu = NULL; struct kvm_sregs *kvm_sregs = NULL; - if (vcpu->kvm->mm != current->mm) + if (vcpu->kvm->mm != current->mm || vcpu->kvm->vm_bugged) return -EIO; if (unlikely(_IOC_TYPE(ioctl) != KVMIO)) @@ -2877,7 +2877,7 @@ void __user *argp = compat_ptr(arg); int r; - if (vcpu->kvm->mm != current->mm) + if (vcpu->kvm->mm != current->mm || vcpu->kvm->vm_bugged) return -EIO; switch (ioctl) { @@ -2935,7 +2935,7 @@ { struct kvm_device *dev = filp->private_data; - if (dev->kvm->mm != current->mm) + if (dev->kvm->mm != current->mm || dev->kvm->vm_bugged) return -EIO; switch (ioctl) { @@ -3100,7 +3100,7 @@ void __user *argp = (void __user *)arg; int r; - if (kvm->mm != current->mm) + if (kvm->mm != current->mm || kvm->vm_bugged) return -EIO; switch (ioctl) { case KVM_CREATE_VCPU: @@ -3277,7 +3277,7 @@ struct kvm *kvm = filp->private_data; int r; - if (kvm->mm != current->mm) + if (kvm->mm != current->mm || kvm->vm_bugged) return -EIO; switch (ioctl) { case KVM_GET_DIRTY_LOG: {