vdpa_sim_blk: call vringh_complete_iotlb() also in the error path

Call vringh_complete_iotlb() even when we encounter a serious error
that prevents us from writing the status in the "in" header
(e.g. the header length is incorrect, etc.).

The guest is misbehaving, so maybe the ring is in a bad state, but
let's avoid making things worse.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20220630153221.83371-4-sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Stefano Garzarella 2022-06-30 17:32:21 +02:00 committed by Michael S. Tsirkin
parent 9c4df0900f
commit 8472019eec

View file

@ -63,6 +63,7 @@ static bool vdpasim_blk_handle_req(struct vdpasim *vdpasim,
{
size_t pushed = 0, to_pull, to_push;
struct virtio_blk_outhdr hdr;
bool handled = false;
ssize_t bytes;
loff_t offset;
u64 sector;
@ -78,12 +79,12 @@ static bool vdpasim_blk_handle_req(struct vdpasim *vdpasim,
if (vq->out_iov.used < 1 || vq->in_iov.used < 1) {
dev_dbg(&vdpasim->vdpa.dev, "missing headers - out_iov: %u in_iov %u\n",
vq->out_iov.used, vq->in_iov.used);
return false;
goto err;
}
if (vq->in_iov.iov[vq->in_iov.used - 1].iov_len < 1) {
dev_dbg(&vdpasim->vdpa.dev, "request in header too short\n");
return false;
goto err;
}
/* The last byte is the status and we checked if the last iov has
@ -97,7 +98,7 @@ static bool vdpasim_blk_handle_req(struct vdpasim *vdpasim,
sizeof(hdr));
if (bytes != sizeof(hdr)) {
dev_dbg(&vdpasim->vdpa.dev, "request out header too short\n");
return false;
goto err;
}
to_pull -= bytes;
@ -182,16 +183,19 @@ static bool vdpasim_blk_handle_req(struct vdpasim *vdpasim,
/* Last byte is the status */
bytes = vringh_iov_push_iotlb(&vq->vring, &vq->in_iov, &status, 1);
if (bytes != 1)
return false;
goto err;
pushed += bytes;
/* Make sure data is wrote before advancing index */
smp_wmb();
handled = true;
err:
vringh_complete_iotlb(&vq->vring, vq->head, pushed);
return true;
return handled;
}
static void vdpasim_blk_work(struct work_struct *work)