[Qemu-devel] [PATCH v2] virtio-scsi: Fix num_queue input validation

[Fam Zheng <famz@redhat.com>]

We need to count the ctrlq and eventq, and also cleanup before
returning. Besides, the format string should be unsigned.

The number could never be less than zero.

Signed-off-by: Fam Zheng <famz@redhat.com>
---
 hw/scsi/virtio-scsi.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 7d40ecc..fdcacfd 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -804,10 +804,12 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp,
     virtio_init(vdev, "virtio-scsi", VIRTIO_ID_SCSI,
                 sizeof(VirtIOSCSIConfig));
 
-    if (s->conf.num_queues <= 0 || s->conf.num_queues > VIRTIO_PCI_QUEUE_MAX) {
-        error_setg(errp, "Invalid number of queues (= %" PRId32 "), "
+    if (s->conf.num_queues == 0 ||
+            s->conf.num_queues > VIRTIO_PCI_QUEUE_MAX - 2) {
+        error_setg(errp, "Invalid number of queues (= %" PRIu32 "), "
                          "must be a positive integer less than %d.",
-                   s->conf.num_queues, VIRTIO_PCI_QUEUE_MAX);
+                   s->conf.num_queues, VIRTIO_PCI_QUEUE_MAX - 2);
+        virtio_cleanup(vdev);
         return;
     }
     s->cmd_vqs = g_malloc0(s->conf.num_queues * sizeof(VirtQueue *));
-- 
1.9.3