From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756223AbbCXRKN (ORCPT ); Tue, 24 Mar 2015 13:10:13 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:34064 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756166AbbCXRKJ (ORCPT ); Tue, 24 Mar 2015 13:10:09 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sagi Grimberg , Slava Shwartsman , Nicholas Bellinger Subject: [PATCH 3.19 122/123] iscsi-target: Avoid early conn_logout_comp for iser connections Date: Tue, 24 Mar 2015 16:47:11 +0100 Message-Id: <20150324154429.433028916@linuxfoundation.org> X-Mailer: git-send-email 2.3.3 In-Reply-To: <20150324154423.655554012@linuxfoundation.org> References: <20150324154423.655554012@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicholas Bellinger commit f068fbc82e7696d67b1bb8189306865bedf368b6 upstream. This patch fixes a iser specific logout bug where early complete() of conn->conn_logout_comp in iscsit_close_connection() was causing isert_wait4logout() to complete too soon, triggering a use after free NULL pointer dereference of iscsi_conn memory. The complete() was originally added for traditional iscsi-target when a ISCSI_LOGOUT_OP failed in iscsi_target_rx_opcode(), but given iser-target does not wait in logout failure, this special case needs to be avoided. Reported-by: Sagi Grimberg Cc: Sagi Grimberg Cc: Slava Shwartsman Signed-off-by: Nicholas Bellinger Signed-off-by: Greg Kroah-Hartman --- drivers/target/iscsi/iscsi_target.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -4221,11 +4221,17 @@ int iscsit_close_connection( pr_debug("Closing iSCSI connection CID %hu on SID:" " %u\n", conn->cid, sess->sid); /* - * Always up conn_logout_comp just in case the RX Thread is sleeping - * and the logout response never got sent because the connection - * failed. + * Always up conn_logout_comp for the traditional TCP case just in case + * the RX Thread in iscsi_target_rx_opcode() is sleeping and the logout + * response never got sent because the connection failed. + * + * However for iser-target, isert_wait4logout() is using conn_logout_comp + * to signal logout response TX interrupt completion. Go ahead and skip + * this for iser since isert_rx_opcode() does not wait on logout failure, + * and to avoid iscsi_conn pointer dereference in iser-target code. */ - complete(&conn->conn_logout_comp); + if (conn->conn_transport->transport_type == ISCSI_TCP) + complete(&conn->conn_logout_comp); iscsi_release_thread_set(conn);