diff options
| author | Marios Pomonis <pomonis@google.com> | 2019-12-11 12:47:42 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-02-14 16:29:57 -0500 |
| commit | 32779dea5a835c3a904030507a08944dce9e51a9 (patch) | |
| tree | 19f92bc4716b0625eed5d3fcf23270bff925ef6f /arch | |
| parent | 90dcf223d1f191a9d0c0b39226018834bf45695c (diff) | |
KVM: x86: Protect kvm_hv_msr_[get|set]_crash_data() from Spectre-v1/L1TF attacks
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>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/hyperv.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 62cf8c915e95..fce6fa012d30 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -26,6 +26,7 @@ #include "hyperv.h" #include <linux/kvm_host.h> +#include <linux/nospec.h> #include <trace/events/kvm.h> #include "trace.h" @@ -53,11 +54,12 @@ static int kvm_hv_msr_get_crash_data(struct kvm_vcpu *vcpu, 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; } @@ -96,11 +98,12 @@ static int kvm_hv_msr_set_crash_data(struct kvm_vcpu *vcpu, 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; } |