From 19e2090fb246ca21b3e569ead51a6a7a1748eadd Mon Sep 17 00:00:00 2001 From: Sagi Grimberg Date: Tue, 2 Dec 2014 16:57:26 +0200 Subject: [PATCH] iser-target: Fix connected_handler + teardown flow race Take isert_conn pointer from cm_id->qp->qp_context. This will allow us to know that the cm_id context is always the network portal. This will make the cm_id event check (connection or network portal) more reliable. In order to avoid a NULL dereference in cma_id->qp->qp_context we destroy the qp after we destroy the cm_id (and make the dereference safe). session stablishment/teardown sequences can happen in parallel, we should take into account that connected_handler might race with connection teardown flow. Also, protect isert_conn->conn_device->active_qps decrement within the error patch during QP creation failure and the normal teardown path in isert_connect_release(). Squashed: iser-target: Decrement completion context active_qps in error flow Signed-off-by: Sagi Grimberg Cc: # v3.10+ Signed-off-by: Nicholas Bellinger --- drivers/infiniband/ulp/isert/ib_isert.c | 31 +++++++++++++++---------- 1 file changed, 19 insertions(+), 12 deletions(-) diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c index a0fd77bf8f88..054fa425d09e 100644 --- a/drivers/infiniband/ulp/isert/ib_isert.c +++ b/drivers/infiniband/ulp/isert/ib_isert.c @@ -141,12 +141,18 @@ isert_conn_setup_qp(struct isert_conn *isert_conn, struct rdma_cm_id *cma_id, ret = rdma_create_qp(cma_id, isert_conn->conn_pd, &attr); if (ret) { pr_err("rdma_create_qp failed for cma_id %d\n", ret); - return ret; + goto err; } isert_conn->conn_qp = cma_id->qp; pr_debug("rdma_create_qp() returned success >>>>>>>>>>>>>>>>>>>>>>>>>.\n"); return 0; +err: + mutex_lock(&device_list_mutex); + device->cq_active_qps[min_index]--; + mutex_unlock(&device_list_mutex); + + return ret; } static void @@ -602,7 +608,6 @@ isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event) spin_lock_init(&isert_conn->conn_lock); INIT_LIST_HEAD(&isert_conn->conn_fr_pool); - cma_id->context = isert_conn; isert_conn->conn_cm_id = cma_id; isert_conn->login_buf = kzalloc(ISCSI_DEF_MAX_RECV_SEG_LEN + @@ -734,18 +739,20 @@ isert_connect_release(struct isert_conn *isert_conn) if (device && device->use_fastreg) isert_conn_free_fastreg_pool(isert_conn); + isert_free_rx_descriptors(isert_conn); + rdma_destroy_id(isert_conn->conn_cm_id); + if (isert_conn->conn_qp) { cq_index = ((struct isert_cq_desc *) isert_conn->conn_qp->recv_cq->cq_context)->cq_index; pr_debug("isert_connect_release: cq_index: %d\n", cq_index); + mutex_lock(&device_list_mutex); isert_conn->conn_device->cq_active_qps[cq_index]--; + mutex_unlock(&device_list_mutex); - rdma_destroy_qp(isert_conn->conn_cm_id); + ib_destroy_qp(isert_conn->conn_qp); } - isert_free_rx_descriptors(isert_conn); - rdma_destroy_id(isert_conn->conn_cm_id); - ib_dereg_mr(isert_conn->conn_mr); ib_dealloc_pd(isert_conn->conn_pd); @@ -768,7 +775,7 @@ isert_connect_release(struct isert_conn *isert_conn) static void isert_connected_handler(struct rdma_cm_id *cma_id) { - struct isert_conn *isert_conn = cma_id->context; + struct isert_conn *isert_conn = cma_id->qp->qp_context; pr_info("conn %p\n", isert_conn); @@ -846,16 +853,16 @@ isert_conn_terminate(struct isert_conn *isert_conn) static int isert_disconnected_handler(struct rdma_cm_id *cma_id) { + struct iscsi_np *np = cma_id->context; + struct isert_np *isert_np = np->np_context; struct isert_conn *isert_conn; - if (!cma_id->qp) { - struct isert_np *isert_np = cma_id->context; - + if (isert_np->np_cm_id == cma_id) { isert_np->np_cm_id = NULL; return -1; } - isert_conn = (struct isert_conn *)cma_id->context; + isert_conn = cma_id->qp->qp_context; mutex_lock(&isert_conn->conn_mutex); isert_conn_terminate(isert_conn); @@ -870,7 +877,7 @@ isert_disconnected_handler(struct rdma_cm_id *cma_id) static void isert_connect_error(struct rdma_cm_id *cma_id) { - struct isert_conn *isert_conn = (struct isert_conn *)cma_id->context; + struct isert_conn *isert_conn = cma_id->qp->qp_context; isert_put_conn(isert_conn); } -- 2.39.5