Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 273dd05f authored by Deepak Kumar Singh's avatar Deepak Kumar Singh
Browse files

soc: qcom: glink_probe: use lock while sending ssr notification 



In ssr handling of remote subsystem down, all rpmsg devices are removed
for that edge. If at the same time ssr down is received for other remote
subsystem, it may try to notify already down remote and end up using
invalid rpmsg device which results in use after free.

Store device state in ssr context and update this with holding a lock.
SSR notification function should also use the same lock and perform
check for validity of rpmsg device.

CRs-Fixed: 2580433
Change-Id: I339e228a527f7b6a737944d8e9e53caa31992914
Signed-off-by: default avatarDeepak Kumar Singh <deesin@codeaurora.org>
parent 143e58dc

drivers/soc/qcom/glink_probe.c

+12 −7
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ 


#define GLINK_PROBE_LOG_PAGE_CNT 4

static void *glink_ilc;

static DEFINE_MUTEX(ssr_lock);



#define GLINK_INFO(x, ...)						       \

do {									       \
@@ -126,14 +127,15 @@ static int glink_ssr_ssr_cb(struct notifier_block *this, 
{

	struct glink_ssr_nb *nb = container_of(this, struct glink_ssr_nb, nb);

	struct glink_ssr *ssr = nb->ssr;

	struct device *dev = ssr->dev;

	struct device *dev;

	struct do_cleanup_msg msg;

	int ret;



	if (!dev || !ssr->ept)

		return NOTIFY_DONE;



	kref_get(&ssr->refcount);

	mutex_lock(&ssr_lock);

	dev = ssr->dev;

	if (!dev || !ssr->ept)

		goto out;



	if (code == SUBSYS_AFTER_SHUTDOWN) {

		ssr->seq_num++;
@@ -153,8 +155,7 @@ static int glink_ssr_ssr_cb(struct notifier_block *this, 
		if (ret) {

			GLINK_ERR(dev, "fail to send do cleanup to %s %d\n",

				  nb->ssr_label, ret);

			kref_put(&ssr->refcount, glink_ssr_release);

			return NOTIFY_DONE;

			goto out;

		}



		ret = wait_for_completion_timeout(&ssr->completion, HZ);
@@ -162,6 +163,8 @@ static int glink_ssr_ssr_cb(struct notifier_block *this, 
			GLINK_ERR(dev, "timeout waiting for cleanup resp\n");



	}

out:

	mutex_unlock(&ssr_lock);

	kref_put(&ssr->refcount, glink_ssr_release);

	return NOTIFY_DONE;

}
@@ -274,10 +277,12 @@ static void glink_ssr_remove(struct rpmsg_device *rpdev) 
{

	struct glink_ssr *ssr = dev_get_drvdata(&rpdev->dev);



	mutex_lock(&ssr_lock);

	ssr->dev = NULL;

	ssr->ept = NULL;

	dev_set_drvdata(&rpdev->dev, NULL);

	mutex_unlock(&ssr_lock);



	dev_set_drvdata(&rpdev->dev, NULL);

	schedule_work(&ssr->unreg_work);

}