From: Marios Pomonis pomonis@google.com
commit 8618793750071d66028584a83ed0b4fa7eb4f607 upstream.
This fixes Spectre-v1/L1TF vulnerabilities in kvm_hv_msr_get_crash_data() and kvm_hv_msr_set_crash_data(). These functions contain index computations that use the (attacker-controlled) MSR number.
Fixes: e7d9513b60e8 ("kvm/x86: added hyper-v crash msrs into kvm hyperv context")
Signed-off-by: Nick Finco nifi@google.com Signed-off-by: Marios Pomonis pomonis@google.com Reviewed-by: Andrew Honig ahonig@google.com Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kvm/hyperv.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
--- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -747,11 +747,12 @@ static int kvm_hv_msr_get_crash_data(str u32 index, u64 *pdata) { struct kvm_hv *hv = &vcpu->kvm->arch.hyperv; + size_t size = ARRAY_SIZE(hv->hv_crash_param);
- if (WARN_ON_ONCE(index >= ARRAY_SIZE(hv->hv_crash_param))) + if (WARN_ON_ONCE(index >= size)) return -EINVAL;
- *pdata = hv->hv_crash_param[index]; + *pdata = hv->hv_crash_param[array_index_nospec(index, size)]; return 0; }
@@ -790,11 +791,12 @@ static int kvm_hv_msr_set_crash_data(str u32 index, u64 data) { struct kvm_hv *hv = &vcpu->kvm->arch.hyperv; + size_t size = ARRAY_SIZE(hv->hv_crash_param);
- if (WARN_ON_ONCE(index >= ARRAY_SIZE(hv->hv_crash_param))) + if (WARN_ON_ONCE(index >= size)) return -EINVAL;
- hv->hv_crash_param[index] = data; + hv->hv_crash_param[array_index_nospec(index, size)] = data; return 0; }