Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936189AbdLRQnB (ORCPT ); Mon, 18 Dec 2017 11:43:01 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:43266 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934673AbdLRQNr (ORCPT ); Mon, 18 Dec 2017 11:13:47 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Bart Van Assche , Christoph Hellwig , Mike Christie , Hannes Reinecke , Nicholas Bellinger , Sasha Levin Subject: [PATCH 4.14 072/178] target/iscsi: Detect conn_cmd_list corruption early Date: Mon, 18 Dec 2017 16:48:28 +0100 Message-Id: <20171218152923.631972924@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171218152920.567991776@linuxfoundation.org> References: <20171218152920.567991776@linuxfoundation.org> User-Agent: quilt/0.65 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 Content-Length: 1842 Lines: 52 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche [ Upstream commit 6eaf69e4ec075f5af236c0c89f75639a195db904 ] Certain behavior of the initiator can cause the target driver to send both a reject and a SCSI response. If that happens two target_put_sess_cmd() calls will occur without the command having been removed from conn_cmd_list. In other words, conn_cmd_list will get corrupted once the freed memory is reused. Although the Linux kernel can detect list corruption if list debugging is enabled, in this case the context in which list corruption is detected is not related to the context that caused list corruption. Hence add WARN_ON() statements that report the context that is causing list corruption. Signed-off-by: Bart Van Assche Cc: Christoph Hellwig Cc: Mike Christie Reviewed-by: Hannes Reinecke Signed-off-by: Nicholas Bellinger Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/target/iscsi/iscsi_target_util.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/target/iscsi/iscsi_target_util.c +++ b/drivers/target/iscsi/iscsi_target_util.c @@ -694,6 +694,8 @@ void iscsit_release_cmd(struct iscsi_cmd struct iscsi_session *sess; struct se_cmd *se_cmd = &cmd->se_cmd; + WARN_ON(!list_empty(&cmd->i_conn_node)); + if (cmd->conn) sess = cmd->conn->sess; else @@ -716,6 +718,8 @@ void __iscsit_free_cmd(struct iscsi_cmd { struct iscsi_conn *conn = cmd->conn; + WARN_ON(!list_empty(&cmd->i_conn_node)); + if (cmd->data_direction == DMA_TO_DEVICE) { iscsit_stop_dataout_timer(cmd); iscsit_free_r2ts_from_list(cmd);