usb: typec: ucsi: displayport: Fix a potential race during registration (081da132) · Commits · 戴 / test

Locking the connector in ucsi_register_displayport() to make sure that nothing can access the displayport alternate mode before the function has finished and the alternate mode is actually ready. Fixes: ("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/20200311130006.41288-3-heikki.krogerus@linux.intel.com Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/ucsi/displayport.c

+8 −1

Original line number	Diff line number	Diff line
		@@ -288,6 +288,8 @@ struct typec_altmode ucsi_register_displayport(struct ucsi_connector con,
		struct typec_altmode *alt;
		struct ucsi_dp *dp;

		mutex_lock(&con->lock);

		/* We can't rely on the firmware with the capabilities. */
		desc->vdo \|= DP_CAP_DP_SIGNALING \| DP_CAP_RECEPTACLE;

		@@ -296,12 +298,15 @@ struct typec_altmode ucsi_register_displayport(struct ucsi_connector con,
		desc->vdo \|= all_assignments << 16;

		alt = typec_port_register_altmode(con->port, desc);
		if (IS_ERR(alt))
		if (IS_ERR(alt)) {
		mutex_unlock(&con->lock);
		return alt;
		}

		dp = devm_kzalloc(&alt->dev, sizeof(*dp), GFP_KERNEL);
		if (!dp) {
		typec_unregister_altmode(alt);
		mutex_unlock(&con->lock);
		return ERR_PTR(-ENOMEM);
		}

		@@ -314,5 +319,7 @@ struct typec_altmode ucsi_register_displayport(struct ucsi_connector con,
		alt->ops = &ucsi_displayport_ops;
		typec_altmode_set_drvdata(alt, dp);

		mutex_unlock(&con->lock);

		return alt;
		}

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