IB/iser: Avoid dereferencing iscsi_iser conn object when not bound to iser connection

Fix a possible NULL pointer dereference in disconnection flow. This
can happen if the target disconnected/rejected the connection request,
e.g before the binding stage between iscsi connection to the transport
connection.

Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/infiniband/ulp/iser/iser_verbs.c b/drivers/infiniband/ulp/iser/iser_verbs.c
index afe95674008be88104d384923129d40fda9f75e8..ca37edef27910cc188ab89a6e626ce29d6d5a344 100644 (file)
--- a/drivers/infiniband/ulp/iser/iser_verbs.c
+++ b/drivers/infiniband/ulp/iser/iser_verbs.c
@@ -652,9 +652,13 @@ static int iser_disconnected_handler(struct rdma_cm_id *cma_id)
        /* getting here when the state is UP means that the conn is being *
         * terminated asynchronously from the iSCSI layer's perspective.  */
        if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP,
-                                     ISER_CONN_TERMINATING))
-               iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn,
-                                  ISCSI_ERR_CONN_FAILED);
+                                       ISER_CONN_TERMINATING)){
+               if (ib_conn->iser_conn)
+                       iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn,
+                                          ISCSI_ERR_CONN_FAILED);
+               else
+                       iser_err("iscsi_iser connection isn't bound\n");
+       }
 
        /* Complete the termination process if no posts are pending */
        if (ib_conn->post_recv_buf_count == 0 &&