Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756829AbcDJUhA (ORCPT ); Sun, 10 Apr 2016 16:37:00 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:58150 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755698AbcDJUgD (ORCPT ); Sun, 10 Apr 2016 16:36:03 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jenny Derzhavetz , Sagi Grimberg , Nicholas Bellinger Subject: [PATCH 4.4 188/210] iser-target: Rework connection termination Date: Sun, 10 Apr 2016 11:36:49 -0700 Message-Id: <20160410183533.306536266@linuxfoundation.org> X-Mailer: git-send-email 2.8.0 In-Reply-To: <20160410183526.651820045@linuxfoundation.org> References: <20160410183526.651820045@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 Content-Length: 6763 Lines: 227 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jenny Derzhavetz commit 6d1fba0c2cc7efe42fd761ecbba833ed0ea7b07e upstream. When we receive an event that triggers connection termination, we have a a couple of things we may want to do: 1. In case we are already terminating, bailout early 2. In case we are connected but not bound, disconnect and schedule a connection cleanup silently (don't reinstate) 3. In case we are connected and bound, disconnect and reinstate the connection This rework fixes a bug that was detected against a mis-behaved initiator which rejected our rdma_cm accept, in this stage the isert_conn is no bound and reinstate caused a bogus dereference. What's great about this is that we don't need the post_recv_buf_count anymore, so get rid of it. Signed-off-by: Jenny Derzhavetz Signed-off-by: Sagi Grimberg Signed-off-by: Nicholas Bellinger Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/ulp/isert/ib_isert.c | 107 +++++++++++++++----------------- drivers/infiniband/ulp/isert/ib_isert.h | 1 2 files changed, 52 insertions(+), 56 deletions(-) --- a/drivers/infiniband/ulp/isert/ib_isert.c +++ b/drivers/infiniband/ulp/isert/ib_isert.c @@ -66,6 +66,7 @@ isert_rdma_accept(struct isert_conn *ise struct rdma_cm_id *isert_setup_id(struct isert_np *isert_np); static void isert_release_work(struct work_struct *work); +static void isert_wait4flush(struct isert_conn *isert_conn); static inline bool isert_prot_cmd(struct isert_conn *conn, struct se_cmd *cmd) @@ -815,6 +816,25 @@ isert_put_conn(struct isert_conn *isert_ kref_put(&isert_conn->kref, isert_release_kref); } +static void +isert_handle_unbound_conn(struct isert_conn *isert_conn) +{ + struct isert_np *isert_np = isert_conn->cm_id->context; + + mutex_lock(&isert_np->mutex); + if (!list_empty(&isert_conn->node)) { + /* + * This means iscsi doesn't know this connection + * so schedule a cleanup ourselves + */ + list_del_init(&isert_conn->node); + isert_put_conn(isert_conn); + complete(&isert_conn->wait); + queue_work(isert_release_wq, &isert_conn->release_work); + } + mutex_unlock(&isert_np->mutex); +} + /** * isert_conn_terminate() - Initiate connection termination * @isert_conn: isert connection struct @@ -832,24 +852,19 @@ isert_conn_terminate(struct isert_conn * { int err; - switch (isert_conn->state) { - case ISER_CONN_TERMINATING: - break; - case ISER_CONN_UP: - case ISER_CONN_BOUND: - case ISER_CONN_FULL_FEATURE: /* FALLTHRU */ - isert_info("Terminating conn %p state %d\n", - isert_conn, isert_conn->state); - isert_conn->state = ISER_CONN_TERMINATING; - err = rdma_disconnect(isert_conn->cm_id); - if (err) - isert_warn("Failed rdma_disconnect isert_conn %p\n", - isert_conn); - break; - default: - isert_warn("conn %p teminating in state %d\n", - isert_conn, isert_conn->state); - } + if (isert_conn->state >= ISER_CONN_TERMINATING) + return; + + isert_info("Terminating conn %p state %d\n", + isert_conn, isert_conn->state); + isert_conn->state = ISER_CONN_TERMINATING; + err = rdma_disconnect(isert_conn->cm_id); + if (err) + isert_warn("Failed rdma_disconnect isert_conn %p\n", + isert_conn); + + isert_info("conn %p completing wait\n", isert_conn); + complete(&isert_conn->wait); } static int @@ -883,30 +898,27 @@ static int isert_disconnected_handler(struct rdma_cm_id *cma_id, enum rdma_cm_event_type event) { - struct isert_np *isert_np = cma_id->context; struct isert_conn *isert_conn = cma_id->qp->qp_context; - bool terminating = false; mutex_lock(&isert_conn->mutex); - terminating = (isert_conn->state == ISER_CONN_TERMINATING); - isert_conn_terminate(isert_conn); - mutex_unlock(&isert_conn->mutex); - - isert_info("conn %p completing wait\n", isert_conn); - complete(&isert_conn->wait); - - if (terminating) - goto out; - - mutex_lock(&isert_np->mutex); - if (!list_empty(&isert_conn->node)) { - list_del_init(&isert_conn->node); - isert_put_conn(isert_conn); - queue_work(isert_release_wq, &isert_conn->release_work); + switch (isert_conn->state) { + case ISER_CONN_TERMINATING: + break; + case ISER_CONN_UP: + isert_conn_terminate(isert_conn); + isert_wait4flush(isert_conn); + isert_handle_unbound_conn(isert_conn); + break; + case ISER_CONN_BOUND: + case ISER_CONN_FULL_FEATURE: /* FALLTHRU */ + iscsit_cause_connection_reinstatement(isert_conn->conn, 0); + break; + default: + isert_warn("conn %p teminating in state %d\n", + isert_conn, isert_conn->state); } - mutex_unlock(&isert_np->mutex); + mutex_unlock(&isert_conn->mutex); -out: return 0; } @@ -980,13 +992,10 @@ isert_post_recvm(struct isert_conn *iser rx_wr--; rx_wr->next = NULL; /* mark end of work requests list */ - isert_conn->post_recv_buf_count += count; ret = ib_post_recv(isert_conn->qp, isert_conn->rx_wr, &rx_wr_failed); - if (ret) { + if (ret) isert_err("ib_post_recv() failed with ret: %d\n", ret); - isert_conn->post_recv_buf_count -= count; - } return ret; } @@ -1002,12 +1011,9 @@ isert_post_recv(struct isert_conn *isert rx_wr.num_sge = 1; rx_wr.next = NULL; - isert_conn->post_recv_buf_count++; ret = ib_post_recv(isert_conn->qp, &rx_wr, &rx_wr_failed); - if (ret) { + if (ret) isert_err("ib_post_recv() failed with ret: %d\n", ret); - isert_conn->post_recv_buf_count--; - } return ret; } @@ -1120,12 +1126,9 @@ isert_rdma_post_recvl(struct isert_conn rx_wr.sg_list = &sge; rx_wr.num_sge = 1; - isert_conn->post_recv_buf_count++; ret = ib_post_recv(isert_conn->qp, &rx_wr, &rx_wr_fail); - if (ret) { + if (ret) isert_err("ib_post_recv() failed: %d\n", ret); - isert_conn->post_recv_buf_count--; - } return ret; } @@ -1620,7 +1623,6 @@ isert_rcv_completion(struct iser_rx_desc ib_dma_sync_single_for_device(ib_dev, rx_dma, rx_buflen, DMA_FROM_DEVICE); - isert_conn->post_recv_buf_count--; } static int @@ -2060,11 +2062,6 @@ isert_cq_comp_err(struct isert_conn *ise isert_unmap_tx_desc(desc, ib_dev); else isert_completion_put(desc, isert_cmd, ib_dev, true); - } else { - isert_conn->post_recv_buf_count--; - if (!isert_conn->post_recv_buf_count && - isert_conn->state >= ISER_CONN_BOUND) - iscsit_cause_connection_reinstatement(isert_conn->conn, 0); } } --- a/drivers/infiniband/ulp/isert/ib_isert.h +++ b/drivers/infiniband/ulp/isert/ib_isert.h @@ -145,7 +145,6 @@ struct isert_device; struct isert_conn { enum iser_conn_state state; - int post_recv_buf_count; u32 responder_resources; u32 initiator_depth; bool pi_support;