From patchwork Tue Aug 10 17:30:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 495877 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1F57CC4338F for ; Tue, 10 Aug 2021 17:39:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0655160EBD for ; Tue, 10 Aug 2021 17:39:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233512AbhHJRjt (ORCPT ); Tue, 10 Aug 2021 13:39:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:57682 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234993AbhHJRix (ORCPT ); Tue, 10 Aug 2021 13:38:53 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3D72D61153; Tue, 10 Aug 2021 17:36:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628617004; bh=K0wODNoz+RecPUHNbQX1zVaU8w3RmzPHCktPrvzONCs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uRNwGX5IDez9QAjw1WOyL3EgaA2vaEnq2kHKB555NNpLK76SlM9hK+3t2RZQxsMtr MCHhuixhJx03TbfW1hssVq7w+ZgO4Uziu/B11RNVDMutQaKpClHcfjqc3BnNrryQi9 cbDiUTW/bZZV+zFtTWo/ey3oq0H3LlPdFf4khJQc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tyler Hicks , Sumit Garg , Jarkko Sakkinen , Jens Wiklander Subject: [PATCH 5.4 55/85] tpm_ftpm_tee: Free and unregister TEE shared memory during kexec Date: Tue, 10 Aug 2021 19:30:28 +0200 Message-Id: <20210810172950.097063274@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210810172948.192298392@linuxfoundation.org> References: <20210810172948.192298392@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Tyler Hicks commit dfb703ad2a8d366b829818a558337be779746575 upstream. dma-buf backed shared memory cannot be reliably freed and unregistered during a kexec operation even when tee_shm_free() is called on the shm from a .shutdown hook. The problem occurs because dma_buf_put() calls fput() which then uses task_work_add(), with the TWA_RESUME parameter, to queue tee_shm_release() to be called before the current task returns to user mode. However, the current task never returns to user mode before the kexec completes so the memory is never freed nor unregistered. Use tee_shm_alloc_kernel_buf() to avoid dma-buf backed shared memory allocation so that tee_shm_free() can directly call tee_shm_release(). This will ensure that the shm can be freed and unregistered during a kexec operation. Fixes: 09e574831b27 ("tpm/tpm_ftpm_tee: A driver for firmware TPM running inside TEE") Fixes: 1760eb689ed6 ("tpm/tpm_ftpm_tee: add shutdown call back") Cc: stable@vger.kernel.org Signed-off-by: Tyler Hicks Reviewed-by: Sumit Garg Acked-by: Jarkko Sakkinen Signed-off-by: Jens Wiklander Signed-off-by: Greg Kroah-Hartman --- drivers/char/tpm/tpm_ftpm_tee.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/char/tpm/tpm_ftpm_tee.c +++ b/drivers/char/tpm/tpm_ftpm_tee.c @@ -255,11 +255,11 @@ static int ftpm_tee_probe(struct platfor pvt_data->session = sess_arg.session; /* Allocate dynamic shared memory with fTPM TA */ - pvt_data->shm = tee_shm_alloc(pvt_data->ctx, - MAX_COMMAND_SIZE + MAX_RESPONSE_SIZE, - TEE_SHM_MAPPED | TEE_SHM_DMA_BUF); + pvt_data->shm = tee_shm_alloc_kernel_buf(pvt_data->ctx, + MAX_COMMAND_SIZE + + MAX_RESPONSE_SIZE); if (IS_ERR(pvt_data->shm)) { - dev_err(dev, "%s: tee_shm_alloc failed\n", __func__); + dev_err(dev, "%s: tee_shm_alloc_kernel_buf failed\n", __func__); rc = -ENOMEM; goto out_shm_alloc; }