From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423411AbcE3Vui (ORCPT ); Mon, 30 May 2016 17:50:38 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:52852 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422705AbcE3VA0 (ORCPT ); Mon, 30 May 2016 17:00:26 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexander Usyskin , Tomas Winkler Subject: [PATCH 4.5 40/87] mei: fix NULL dereferencing during FW initiated disconnection Date: Mon, 30 May 2016 13:49:38 -0700 Message-Id: <20160530204934.982869737@linuxfoundation.org> X-Mailer: git-send-email 2.8.3 In-Reply-To: <20160530204933.149873142@linuxfoundation.org> References: <20160530204933.149873142@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexander Usyskin commit 6a8d648c8d1824117a9e9edb948ed1611fb013c0 upstream. In the case when disconnection is initiated from the FW the driver is flushing items from the write control list while iterating over it: mei_irq_write_handler() list_for_each_entry_safe(ctrl_wr_list) <-- outer loop mei_cl_irq_disconnect_rsp() mei_cl_set_disconnected() mei_io_list_flush(ctrl_wr_list) <-- destorying list We move the list flushing to the completion routine. Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman --- drivers/misc/mei/client.c | 4 ++++ drivers/misc/mei/hbm.c | 3 +-- drivers/misc/mei/interrupt.c | 5 +---- 3 files changed, 6 insertions(+), 6 deletions(-) --- a/drivers/misc/mei/client.c +++ b/drivers/misc/mei/client.c @@ -1735,6 +1735,10 @@ void mei_cl_complete(struct mei_cl *cl, wake_up(&cl->wait); break; + case MEI_FOP_DISCONNECT_RSP: + mei_io_cb_free(cb); + mei_cl_set_disconnected(cl); + break; default: BUG_ON(0); } --- a/drivers/misc/mei/hbm.c +++ b/drivers/misc/mei/hbm.c @@ -873,8 +873,7 @@ static int mei_hbm_fw_disconnect_req(str cb = mei_io_cb_init(cl, MEI_FOP_DISCONNECT_RSP, NULL); if (!cb) return -ENOMEM; - cl_dbg(dev, cl, "add disconnect response as first\n"); - list_add(&cb->list, &dev->ctrl_wr_list.list); + list_add_tail(&cb->list, &dev->ctrl_wr_list.list); } return 0; } --- a/drivers/misc/mei/interrupt.c +++ b/drivers/misc/mei/interrupt.c @@ -184,10 +184,7 @@ static int mei_cl_irq_disconnect_rsp(str return -EMSGSIZE; ret = mei_hbm_cl_disconnect_rsp(dev, cl); - mei_cl_set_disconnected(cl); - mei_io_cb_free(cb); - mei_me_cl_put(cl->me_cl); - cl->me_cl = NULL; + list_move_tail(&cb->list, &cmpl_list->list); return ret; }