diff options
author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2022-03-25 16:21:38 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-08 15:24:07 +0300 |
commit | 569a229142e95610adc1041ae9ca1f417c4c6a3e (patch) | |
tree | c37e5bd900901dcf4e8456030493a4fa89df3ea9 | |
parent | 81e5b16de862866e7f09a1b00b49f97a9bc23a78 (diff) | |
download | linux-569a229142e95610adc1041ae9ca1f417c4c6a3e.tar.xz |
KVM: x86: Check lapic_in_kernel() before attempting to set a SynIC irq
commit 7ec37d1cbe17d8189d9562178d8b29167fe1c31a upstream.
When KVM_CAP_HYPERV_SYNIC{,2} is activated, KVM already checks for
irqchip_in_kernel() so normally SynIC irqs should never be set. It is,
however, possible for a misbehaving VMM to write to SYNIC/STIMER MSRs
causing erroneous behavior.
The immediate issue being fixed is that kvm_irq_delivery_to_apic()
(kvm_irq_delivery_to_apic_fast()) crashes when called with
'irq.shorthand = APIC_DEST_SELF' and 'src == NULL'.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20220325132140.25650-2-vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | arch/x86/kvm/hyperv.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index d831c0a40f6e..ac95acf8d6ac 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -446,6 +446,9 @@ static int synic_set_irq(struct kvm_vcpu_hv_synic *synic, u32 sint) struct kvm_lapic_irq irq; int ret, vector; + if (KVM_BUG_ON(!lapic_in_kernel(vcpu), vcpu->kvm)) + return -EINVAL; + if (sint >= ARRAY_SIZE(synic->sint)) return -EINVAL; |