From: G. Campana <gcampana@quarkslab.com>
Date: Thu, 19 Jan 2017 21:37:46 +0000 (+0200)
Subject: virtio_console: fix a crash in config_work_handler
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=23c7f01691a131c4d29c9d7d00f89d888f2b008a;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git

virtio_console: fix a crash in config_work_handler


[ Upstream commit 8379cadf71c3ee8173a1c6fc1ea7762a9638c047 ]

Using control_work instead of config_work as the 3rd argument to
container_of results in an invalid portdev pointer. Indeed, the work
structure is initialized as below:

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

It leads to a crash when portdev->vdev is dereferenced later. This
bug
is triggered when the guest uses a virtio-console without multiport
feature and receives a config_changed virtio interrupt.

Signed-off-by: G. Campana <gcampana@quarkslab.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 31e8ae916ba0..be0b09a0fb44 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -1864,7 +1864,7 @@ static void config_work_handler(struct work_struct *work)
 {
 	struct ports_device *portdev;
 
-	portdev = container_of(work, struct ports_device, control_work);
+	portdev = container_of(work, struct ports_device, config_work);
 	if (!use_multiport(portdev)) {
 		struct virtio_device *vdev;
 		struct port *port;