6.12-stable review patch. If anyone has any objections, please let me know.
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From: Andrei Kuchynski akuchynski@chromium.org
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: 59de2a56d127 ("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 --- drivers/usb/typec/class.c | 15 +++++++++++++-- drivers/usb/typec/class.h | 1 + 2 files changed, 14 insertions(+), 2 deletions(-)
--- a/drivers/usb/typec/class.c +++ b/drivers/usb/typec/class.c @@ -932,6 +932,7 @@ struct typec_partner *typec_register_par 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_par 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 typ
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_p 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(struc 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(s
ida_init(&port->mode_ids); mutex_init(&port->port_type_lock); + mutex_init(&port->partner_link_lock);
port->id = id; port->ops = cap->ops; --- a/drivers/usb/typec/class.h +++ b/drivers/usb/typec/class.h @@ -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;