From: Juergen Gross jgross@suse.com
stable inclusion from linux-4.19.201 commit ce1fd5a2262265a8be09b861340a79683cc1f7cf
--------------------------------
commit 76b4f357d0e7d8f6f0013c733e6cba1773c266d3 upstream.
KVM_MAX_VCPU_ID is the maximum vcpu-id of a guest, and not the number of vcpu-ids. Fix array indexed by vcpu-id to have KVM_MAX_VCPU_ID+1 elements.
Note that this is currently no real problem, as KVM_MAX_VCPU_ID is an odd number, resulting in always enough padding being available at the end of those arrays.
Nevertheless this should be fixed in order to avoid rare problems in case someone is using an even number for KVM_MAX_VCPU_ID.
Signed-off-by: Juergen Gross jgross@suse.com Message-Id: 20210701154105.23215-2-jgross@suse.com Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- arch/x86/kvm/ioapic.c | 2 +- arch/x86/kvm/ioapic.h | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c index bac2ec9b4443b..9944b9c7ceeee 100644 --- a/arch/x86/kvm/ioapic.c +++ b/arch/x86/kvm/ioapic.c @@ -96,7 +96,7 @@ static unsigned long ioapic_read_indirect(struct kvm_ioapic *ioapic, static void rtc_irq_eoi_tracking_reset(struct kvm_ioapic *ioapic) { ioapic->rtc_status.pending_eoi = 0; - bitmap_zero(ioapic->rtc_status.dest_map.map, KVM_MAX_VCPU_ID); + bitmap_zero(ioapic->rtc_status.dest_map.map, KVM_MAX_VCPU_ID + 1); }
static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic *ioapic); diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h index ea1a4e0297dae..283f1f489bcac 100644 --- a/arch/x86/kvm/ioapic.h +++ b/arch/x86/kvm/ioapic.h @@ -43,13 +43,13 @@ struct kvm_vcpu;
struct dest_map { /* vcpu bitmap where IRQ has been sent */ - DECLARE_BITMAP(map, KVM_MAX_VCPU_ID); + DECLARE_BITMAP(map, KVM_MAX_VCPU_ID + 1);
/* * Vector sent to a given vcpu, only valid when * the vcpu's bit in map is set */ - u8 vectors[KVM_MAX_VCPU_ID]; + u8 vectors[KVM_MAX_VCPU_ID + 1]; };