KVM: Fix off-by-one in overflow check of KVM_ASSIGN_SET_MSIX_NR

KVM_MAX_MSIX_PER_DEV implies that up to that many MSI-X entries can be
requested. But the kernel so far rejected already the upper limit.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/virt/kvm/assigned-dev.c b/virt/kvm/assigned-dev.c
index 6cc4b97..4e9eaeb 100644 (file)
--- a/virt/kvm/assigned-dev.c
+++ b/virt/kvm/assigned-dev.c
@@ -617,7 +617,7 @@ static int kvm_vm_ioctl_set_msix_nr(struct kvm *kvm,
        if (adev->entries_nr == 0) {
                adev->entries_nr = entry_nr->entry_nr;
                if (adev->entries_nr == 0 ||
-                   adev->entries_nr >= KVM_MAX_MSIX_PER_DEV) {
+                   adev->entries_nr > KVM_MAX_MSIX_PER_DEV) {
                        r = -EINVAL;
                        goto msix_nr_out;
                }