From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:46348 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728175AbeICVtB (ORCPT ); Mon, 3 Sep 2018 17:49:01 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mike Christie , "Martin K. Petersen" , Matthew Wilcox Subject: [PATCH 4.14 157/165] iscsi target: fix session creation failure handling Date: Mon, 3 Sep 2018 18:57:23 +0200 Message-Id: <20180903165704.962049614@linuxfoundation.org> In-Reply-To: <20180903165655.003605184@linuxfoundation.org> References: <20180903165655.003605184@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mike Christie commit 26abc916a898d34c5ad159315a2f683def3c5555 upstream. The problem is that iscsi_login_zero_tsih_s1 sets conn->sess early in iscsi_login_set_conn_values. If the function fails later like when we alloc the idr it does kfree(sess) and leaves the conn->sess pointer set. iscsi_login_zero_tsih_s1 then returns -Exyz and we then call iscsi_target_login_sess_out and access the freed memory. This patch has iscsi_login_zero_tsih_s1 either completely setup the session or completely tear it down, so later in iscsi_target_login_sess_out we can just check for it being set to the connection. Cc: stable@vger.kernel.org Fixes: 0957627a9960 ("iscsi-target: Fix sess allocation leak in...") Signed-off-by: Mike Christie Acked-by: Martin K. Petersen Signed-off-by: Matthew Wilcox Signed-off-by: Greg Kroah-Hartman --- drivers/target/iscsi/iscsi_target_login.c | 35 ++++++++++++++++++------------ 1 file changed, 21 insertions(+), 14 deletions(-) --- a/drivers/target/iscsi/iscsi_target_login.c +++ b/drivers/target/iscsi/iscsi_target_login.c @@ -345,8 +345,7 @@ static int iscsi_login_zero_tsih_s1( pr_err("idr_alloc() for sess_idr failed\n"); iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR, ISCSI_LOGIN_STATUS_NO_RESOURCES); - kfree(sess); - return -ENOMEM; + goto free_sess; } sess->creation_time = get_jiffies_64(); @@ -362,20 +361,28 @@ static int iscsi_login_zero_tsih_s1( ISCSI_LOGIN_STATUS_NO_RESOURCES); pr_err("Unable to allocate memory for" " struct iscsi_sess_ops.\n"); - kfree(sess); - return -ENOMEM; + goto remove_idr; } sess->se_sess = transport_init_session(TARGET_PROT_NORMAL); if (IS_ERR(sess->se_sess)) { iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR, ISCSI_LOGIN_STATUS_NO_RESOURCES); - kfree(sess->sess_ops); - kfree(sess); - return -ENOMEM; + goto free_ops; } return 0; + +free_ops: + kfree(sess->sess_ops); +remove_idr: + spin_lock_bh(&sess_idr_lock); + idr_remove(&sess_idr, sess->session_index); + spin_unlock_bh(&sess_idr_lock); +free_sess: + kfree(sess); + conn->sess = NULL; + return -ENOMEM; } static int iscsi_login_zero_tsih_s2( @@ -1162,13 +1169,13 @@ void iscsi_target_login_sess_out(struct ISCSI_LOGIN_STATUS_INIT_ERR); if (!zero_tsih || !conn->sess) goto old_sess_out; - if (conn->sess->se_sess) - transport_free_session(conn->sess->se_sess); - if (conn->sess->session_index != 0) { - spin_lock_bh(&sess_idr_lock); - idr_remove(&sess_idr, conn->sess->session_index); - spin_unlock_bh(&sess_idr_lock); - } + + transport_free_session(conn->sess->se_sess); + + spin_lock_bh(&sess_idr_lock); + idr_remove(&sess_idr, conn->sess->session_index); + spin_unlock_bh(&sess_idr_lock); + kfree(conn->sess->sess_ops); kfree(conn->sess); conn->sess = NULL;