usb: typec: class: Fix NULL pointer access

commit ec27386de23a511008c53aa2f3434ad180a3ca9a upstream.

Concurrent calls to typec_partner_unlink_device can lead to a NULL pointer
dereference. This patch adds a mutex to protect USB device pointers and
prevent this issue. The same mutex protects both the device pointers and
the partner device registration.

Cc: stable@vger.kernel.org
Fixes: 59de2a56d1 ("usb: typec: Link enumerated USB devices with Type-C partner")
Signed-off-by: Andrei Kuchynski <akuchynski@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20250321143728.4092417-2-akuchynski@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Andrei Kuchynski
2025-03-21 14:37:26 +00:00
committed by Greg Kroah-Hartman
parent 543e0f8765
commit de7c24febd
2 changed files with 14 additions and 2 deletions

View File

@@ -932,6 +932,7 @@ struct typec_partner *typec_register_partner(struct typec_port *port,
partner->dev.type = &typec_partner_dev_type;
dev_set_name(&partner->dev, "%s-partner", dev_name(&port->dev));
mutex_lock(&port->partner_link_lock);
ret = device_register(&partner->dev);
if (ret) {
dev_err(&port->dev, "failed to register partner (%d)\n", ret);
@@ -943,6 +944,7 @@ struct typec_partner *typec_register_partner(struct typec_port *port,
typec_partner_link_device(partner, port->usb2_dev);
if (port->usb3_dev)
typec_partner_link_device(partner, port->usb3_dev);
mutex_unlock(&port->partner_link_lock);
return partner;
}
@@ -963,12 +965,14 @@ void typec_unregister_partner(struct typec_partner *partner)
port = to_typec_port(partner->dev.parent);
mutex_lock(&port->partner_link_lock);
if (port->usb2_dev)
typec_partner_unlink_device(partner, port->usb2_dev);
if (port->usb3_dev)
typec_partner_unlink_device(partner, port->usb3_dev);
device_unregister(&partner->dev);
mutex_unlock(&port->partner_link_lock);
}
EXPORT_SYMBOL_GPL(typec_unregister_partner);
@@ -1862,25 +1866,30 @@ static struct typec_partner *typec_get_partner(struct typec_port *port)
static void typec_partner_attach(struct typec_connector *con, struct device *dev)
{
struct typec_port *port = container_of(con, struct typec_port, con);
struct typec_partner *partner = typec_get_partner(port);
struct typec_partner *partner;
struct usb_device *udev = to_usb_device(dev);
mutex_lock(&port->partner_link_lock);
if (udev->speed < USB_SPEED_SUPER)
port->usb2_dev = dev;
else
port->usb3_dev = dev;
partner = typec_get_partner(port);
if (partner) {
typec_partner_link_device(partner, dev);
put_device(&partner->dev);
}
mutex_unlock(&port->partner_link_lock);
}
static void typec_partner_deattach(struct typec_connector *con, struct device *dev)
{
struct typec_port *port = container_of(con, struct typec_port, con);
struct typec_partner *partner = typec_get_partner(port);
struct typec_partner *partner;
mutex_lock(&port->partner_link_lock);
partner = typec_get_partner(port);
if (partner) {
typec_partner_unlink_device(partner, dev);
put_device(&partner->dev);
@@ -1890,6 +1899,7 @@ static void typec_partner_deattach(struct typec_connector *con, struct device *d
port->usb2_dev = NULL;
else if (port->usb3_dev == dev)
port->usb3_dev = NULL;
mutex_unlock(&port->partner_link_lock);
}
/**
@@ -2425,6 +2435,7 @@ struct typec_port *typec_register_port(struct device *parent,
ida_init(&port->mode_ids);
mutex_init(&port->port_type_lock);
mutex_init(&port->partner_link_lock);
port->id = id;
port->ops = cap->ops;

View File

@@ -56,6 +56,7 @@ struct typec_port {
enum typec_pwr_opmode pwr_opmode;
enum typec_port_type port_type;
struct mutex port_type_lock;
struct mutex partner_link_lock;
enum typec_orientation orientation;
struct typec_switch *sw;