Commit 42a7c0fd authored Sep 16, 2024 by Michael S. Tsirkin Committed by Greg Kroah-Hartman Nov 08, 2024

virtio_console: fix misc probe bugs



[ Upstream commit b9efbe2b8f0177fa97bfab290d60858900aa196b ]

This fixes the following issue discovered by code review:

after vqs have been created, a buggy device can send an interrupt.

A control vq callback will then try to schedule control_work which has
not been initialized yet. Similarly for config interrupt.  Further, in
and out vq callbacks invoke find_port_by_vq which attempts to take
ports_lock which also has not been initialized.

To fix, init all locks and work before creating vqs.

Message-ID: <ad982e975a6160ad110c623c016041311ca15b4f.1726511547.git.mst@redhat.com>
Fixes: 17634ba2 ("virtio: console: Add a new MULTIPORT feature, support for generic ports")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 98d49bc3

drivers/char/virtio_console.c

+10 −8

Original line number	Diff line number	Diff line
		@@ -2075,25 +2075,27 @@ static int virtcons_probe(struct virtio_device *vdev)
		multiport = true;
		}

		err = init_vqs(portdev);
		if (err < 0) {
		dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
		goto free_chrdev;
		}

		spin_lock_init(&portdev->ports_lock);
		INIT_LIST_HEAD(&portdev->ports);
		INIT_LIST_HEAD(&portdev->list);

		virtio_device_ready(portdev->vdev);

		INIT_WORK(&portdev->config_work, &config_work_handler);
		INIT_WORK(&portdev->control_work, &control_work_handler);

		if (multiport) {
		spin_lock_init(&portdev->c_ivq_lock);
		spin_lock_init(&portdev->c_ovq_lock);
		}

		err = init_vqs(portdev);
		if (err < 0) {
		dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
		goto free_chrdev;
		}

		virtio_device_ready(portdev->vdev);

		if (multiport) {
		err = fill_queue(portdev->c_ivq, &portdev->c_ivq_lock);
		if (err < 0) {
		dev_err(&vdev->dev,