[PATCH] tee: optee: Fix missing devices unregister during optee_remove

From: Sumit Garg
Date: Tue Oct 12 2021 - 03:31:42 EST


When OP-TEE driver is built as a module, OP-TEE client devices
registered on TEE bus during probe should be unregistered during
optee_remove. So implement optee_unregister_devices() accordingly.

Fixes: c3fa24af9244 ("tee: optee: add TEE bus device enumeration support")
Reported-by: Sudeep Holla <sudeep.holla@xxxxxxx>
Signed-off-by: Sumit Garg <sumit.garg@xxxxxxxxxx>
---
drivers/tee/optee/core.c | 3 +++
drivers/tee/optee/device.c | 22 ++++++++++++++++++++++
drivers/tee/optee/optee_private.h | 1 +
3 files changed, 26 insertions(+)

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index ccad3c7c8f6d..3915dc574503 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -586,6 +586,9 @@ static int optee_remove(struct platform_device *pdev)
{
struct optee *optee = platform_get_drvdata(pdev);

+ /* Unregister OP-TEE specific client devices on TEE bus */
+ optee_unregister_devices();
+
/*
* Ask OP-TEE to free all cached shared memory objects to decrease
* reference counters and also avoid wild pointers in secure world
diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c
index ec1d24693eba..128a2d2a50a1 100644
--- a/drivers/tee/optee/device.c
+++ b/drivers/tee/optee/device.c
@@ -53,6 +53,13 @@ static int get_devices(struct tee_context *ctx, u32 session,
return 0;
}

+static void optee_release_device(struct device *dev)
+{
+ struct tee_client_device *optee_device = to_tee_client_device(dev);
+
+ kfree(optee_device);
+}
+
static int optee_register_device(const uuid_t *device_uuid)
{
struct tee_client_device *optee_device = NULL;
@@ -63,6 +70,7 @@ static int optee_register_device(const uuid_t *device_uuid)
return -ENOMEM;

optee_device->dev.bus = &tee_bus_type;
+ optee_device->dev.release = optee_release_device;
if (dev_set_name(&optee_device->dev, "optee-ta-%pUb", device_uuid)) {
kfree(optee_device);
return -ENOMEM;
@@ -154,3 +162,17 @@ int optee_enumerate_devices(u32 func)
{
return __optee_enumerate_devices(func);
}
+
+static int __optee_unregister_device(struct device *dev, void *data)
+{
+ if (!strncmp(dev_name(dev), "optee-ta", strlen("optee-ta")))
+ device_unregister(dev);
+
+ return 0;
+}
+
+void optee_unregister_devices(void)
+{
+ bus_for_each_dev(&tee_bus_type, NULL, NULL,
+ __optee_unregister_device);
+}
diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
index e25b216a14ef..39be9aa7bd22 100644
--- a/drivers/tee/optee/optee_private.h
+++ b/drivers/tee/optee/optee_private.h
@@ -183,6 +183,7 @@ void optee_fill_pages_list(u64 *dst, struct page **pages, int num_pages,
#define PTA_CMD_GET_DEVICES 0x0
#define PTA_CMD_GET_DEVICES_SUPP 0x1
int optee_enumerate_devices(u32 func);
+void optee_unregister_devices(void);

/*
* Small helpers
--
2.25.1