6.9-stable review patch. If anyone has any objections, please let me know.
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From: Amit Sunil Dhamne amitsd@google.com
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 --- drivers/usb/typec/tcpm/tcpm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -3014,8 +3014,10 @@ static int tcpm_register_source_caps(str memcpy(caps.pdo, port->source_caps, sizeof(u32) * port->nr_source_caps); caps.role = TYPEC_SOURCE;
- 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))