Commit be353be2 authored by Rijo Thomas's avatar Rijo Thomas Committed by Jens Wiklander
Browse files

tee: amdtee: synchronize access to shm list 



Synchronize access to shm or shared memory buffer list to prevent
race conditions due to concurrent updates to shared shm list by
multiple threads.

Fixes: 757cc3e9 ("tee: add AMD-TEE driver")
Reviewed-by: default avatarDevaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: default avatarRijo Thomas <Rijo-john.Thomas@amd.com>
Signed-off-by: default avatarJens Wiklander <jens.wiklander@linaro.org>
parent ff1f8558

drivers/tee/amdtee/amdtee_private.h

+1 −0
Original line number Diff line number Diff line
@@ -70,6 +70,7 @@ struct amdtee_session { 
struct amdtee_context_data {

	struct list_head sess_list;

	struct list_head shm_list;

	struct mutex shm_mutex;   /* synchronizes access to @shm_list */

};



struct amdtee_driver_data {

drivers/tee/amdtee/core.c

+8 −0
Original line number Diff line number Diff line
@@ -42,6 +42,7 @@ static int amdtee_open(struct tee_context *ctx) 


	INIT_LIST_HEAD(&ctxdata->sess_list);

	INIT_LIST_HEAD(&ctxdata->shm_list);

	mutex_init(&ctxdata->shm_mutex);



	ctx->data = ctxdata;

	return 0;
@@ -85,6 +86,7 @@ static void amdtee_release(struct tee_context *ctx) 
		list_del(&sess->list_node);

		release_session(sess);

	}

	mutex_destroy(&ctxdata->shm_mutex);

	kfree(ctxdata);



	ctx->data = NULL;
@@ -155,11 +157,13 @@ u32 get_buffer_id(struct tee_shm *shm) 
	struct amdtee_shm_data *shmdata;

	u32 buf_id = 0;



	mutex_lock(&ctxdata->shm_mutex);

	list_for_each_entry(shmdata, &ctxdata->shm_list, shm_node)

		if (shmdata->kaddr == shm->kaddr) {

			buf_id = shmdata->buf_id;

			break;

		}

	mutex_unlock(&ctxdata->shm_mutex);



	return buf_id;

}
@@ -364,7 +368,9 @@ int amdtee_map_shmem(struct tee_shm *shm) 
	shmnode->kaddr = shm->kaddr;

	shmnode->buf_id = buf_id;

	ctxdata = shm->ctx->data;

	mutex_lock(&ctxdata->shm_mutex);

	list_add(&shmnode->shm_node, &ctxdata->shm_list);

	mutex_unlock(&ctxdata->shm_mutex);



	pr_debug("buf_id :[%x] kaddr[%p]\n", shmnode->buf_id, shmnode->kaddr);
@@ -385,12 +391,14 @@ void amdtee_unmap_shmem(struct tee_shm *shm) 
	handle_unmap_shmem(buf_id);



	ctxdata = shm->ctx->data;

	mutex_lock(&ctxdata->shm_mutex);

	list_for_each_entry(shmnode, &ctxdata->shm_list, shm_node)

		if (buf_id == shmnode->buf_id) {

			list_del(&shmnode->shm_node);

			kfree(shmnode);

			break;

		}

	mutex_unlock(&ctxdata->shm_mutex);

}



int amdtee_invoke_func(struct tee_context *ctx,

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