usb: typec: tcpm: fix use-after-free case in tcpm_register_source_caps

commit e7e921918d905544500ca7a95889f898121ba886 upstream.

There could be a potential use-after-free case in
tcpm_register_source_caps(). This could happen when:
 * new (say invalid) source caps are advertised
 * the existing source caps are unregistered
 * tcpm_register_source_caps() returns with an error as
   usb_power_delivery_register_capabilities() fails

This causes port->partner_source_caps to hold on to the now freed source
caps.

Reset port->partner_source_caps value to NULL after unregistering
existing source caps.

Fixes: 230ecdf71a64 ("usb: typec: tcpm: unregister existing source caps before re-registration")
Cc: stable@vger.kernel.org
Signed-off-by: Amit Sunil Dhamne <amitsd@google.com>
Reviewed-by: Ondrej Jirman <megi@xff.cz>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240514220134.2143181-1-amitsd@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Amit Sunil Dhamne 2024-05-14 15:01:31 -07:00 committed by Greg Kroah-Hartman
parent b641889cc1
commit 04c05d50fa

View File

@ -2436,8 +2436,10 @@ static int tcpm_register_sink_caps(struct tcpm_port *port)
memcpy(caps.pdo, port->sink_caps, sizeof(u32) * port->nr_sink_caps);
caps.role = TYPEC_SINK;
if (cap)
if (cap) {
usb_power_delivery_unregister_capabilities(cap);
port->partner_source_caps = NULL;
}
cap = usb_power_delivery_register_capabilities(port->partner_pd, &caps);
if (IS_ERR(cap))