Unverified Commit a41e95a7 authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

Merge tag 'amdtee-fix-for-v6.6' of... 

Merge tag 'amdtee-fix-for-v6.6' of https://git.linaro.org/people/jens.wiklander/linux-tee into arm/fixes

AMDTEE fix possible use-after-free

* tag 'amdtee-fix-for-v6.6' of https://git.linaro.org/people/jens.wiklander/linux-tee:
  tee: amdtee: fix use-after-free vulnerability in amdtee_close_session

Link: https://lore.kernel.org/r/20231003171835.GA669924@rayden


Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parents 6465e260 f4384b3e

drivers/tee/amdtee/core.c

+6 −4
Original line number Diff line number Diff line
@@ -217,12 +217,12 @@ static int copy_ta_binary(struct tee_context *ctx, void *ptr, void **ta, 
	return rc;

}



/* mutex must be held by caller */

static void destroy_session(struct kref *ref)

{

	struct amdtee_session *sess = container_of(ref, struct amdtee_session,

						   refcount);



	mutex_lock(&session_list_mutex);

	list_del(&sess->list_node);

	mutex_unlock(&session_list_mutex);

	kfree(sess);
@@ -272,7 +272,8 @@ int amdtee_open_session(struct tee_context *ctx, 
	if (arg->ret != TEEC_SUCCESS) {

		pr_err("open_session failed %d\n", arg->ret);

		handle_unload_ta(ta_handle);

		kref_put(&sess->refcount, destroy_session);

		kref_put_mutex(&sess->refcount, destroy_session,

			       &session_list_mutex);

		goto out;

	}
@@ -290,7 +291,8 @@ int amdtee_open_session(struct tee_context *ctx, 
		pr_err("reached maximum session count %d\n", TEE_NUM_SESSIONS);

		handle_close_session(ta_handle, session_info);

		handle_unload_ta(ta_handle);

		kref_put(&sess->refcount, destroy_session);

		kref_put_mutex(&sess->refcount, destroy_session,

			       &session_list_mutex);

		rc = -ENOMEM;

		goto out;

	}
@@ -331,7 +333,7 @@ int amdtee_close_session(struct tee_context *ctx, u32 session) 
	handle_close_session(ta_handle, session_info);

	handle_unload_ta(ta_handle);



	kref_put(&sess->refcount, destroy_session);

	kref_put_mutex(&sess->refcount, destroy_session, &session_list_mutex);



	return 0;

}