usb: typec: ucsi: displayport: Fix potential deadlock

The function ucsi_displayport_work() does not access the
connector, so it also must not acquire the connector lock.

This fixes a potential deadlock scenario:

ucsi_displayport_work() -> lock(&con->lock)
typec_altmode_vdm()
dp_altmode_vdm()
dp_altmode_work()
typec_altmode_enter()
ucsi_displayport_enter() -> lock(&con->lock)

Reported-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Fixes: af8622f6a5 ("usb: typec: ucsi: Support for DisplayPort alt mode")
Cc: stable@vger.kernel.org
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240507134316.161999-1-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Heikki Krogerus 2024-05-07 16:43:16 +03:00 committed by Greg Kroah-Hartman
parent 718b36a7b4
commit b791a67f68

View File

@ -275,8 +275,6 @@ static void ucsi_displayport_work(struct work_struct *work)
struct ucsi_dp *dp = container_of(work, struct ucsi_dp, work); struct ucsi_dp *dp = container_of(work, struct ucsi_dp, work);
int ret; int ret;
mutex_lock(&dp->con->lock);
ret = typec_altmode_vdm(dp->alt, dp->header, ret = typec_altmode_vdm(dp->alt, dp->header,
dp->vdo_data, dp->vdo_size); dp->vdo_data, dp->vdo_size);
if (ret) if (ret)
@ -285,8 +283,6 @@ static void ucsi_displayport_work(struct work_struct *work)
dp->vdo_data = NULL; dp->vdo_data = NULL;
dp->vdo_size = 0; dp->vdo_size = 0;
dp->header = 0; dp->header = 0;
mutex_unlock(&dp->con->lock);
} }
void ucsi_displayport_remove_partner(struct typec_altmode *alt) void ucsi_displayport_remove_partner(struct typec_altmode *alt)