virtio-net: fix unmap leak

virtio_net_handle_ctrl() and other functions that process control vq
request call iov_discard_front() which will shorten the iov. This will
lead unmapping in virtqueue_push() leaks mapping.

Fixes this by keeping the original iov untouched and using a temp variable
in those functions.

Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 1417082643-23907-1-git-send-email-jasowang@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Jason Wang 2014-11-27 18:04:03 +08:00 committed by Peter Maydell
parent 4cae4d5aca
commit 771b6ed37e
1 changed files with 3 additions and 2 deletions

View File

@ -798,7 +798,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
VirtQueueElement elem;
size_t s;
struct iovec *iov;
struct iovec *iov, *iov2;
unsigned int iov_cnt;
while (virtqueue_pop(vq, &elem)) {
@ -808,8 +808,8 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
exit(1);
}
iov = elem.out_sg;
iov_cnt = elem.out_num;
iov2 = iov = g_memdup(elem.out_sg, sizeof(struct iovec) * elem.out_num);
s = iov_to_buf(iov, iov_cnt, 0, &ctrl, sizeof(ctrl));
iov_discard_front(&iov, &iov_cnt, sizeof(ctrl));
if (s != sizeof(ctrl)) {
@ -833,6 +833,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
virtqueue_push(vq, &elem, sizeof(status));
virtio_notify(vdev, vq);
g_free(iov2);
}
}