In rds_rdma_cm_event_handler_cmn(), there are some if statements to check whether conn is NULL, such as on lines 65, 96 and 112. But conn is not checked before being used on line 108: trans->cm_connect_complete(conn, event); and on lines 140-143: rdsdebug("DISCONNECT event - dropping connection " "%pI6c->%pI6c\n", &conn->c_laddr, &conn->c_faddr); rds_conn_drop(conn); Thus, possible null-pointer dereferences may occur. To fix these bugs, conn is checked before being used. These bugs are found by a static analysis tool STCheck written by us. Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx> --- net/rds/rdma_transport.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/rds/rdma_transport.c b/net/rds/rdma_transport.c index ff74c4bbb9fc..9986d6065c4d 100644 --- a/net/rds/rdma_transport.c +++ b/net/rds/rdma_transport.c @@ -105,7 +105,8 @@ static int rds_rdma_cm_event_handler_cmn(struct rdma_cm_id *cm_id, break; case RDMA_CM_EVENT_ESTABLISHED: - trans->cm_connect_complete(conn, event); + if (conn) + trans->cm_connect_complete(conn, event); break; case RDMA_CM_EVENT_REJECTED: @@ -137,6 +138,8 @@ static int rds_rdma_cm_event_handler_cmn(struct rdma_cm_id *cm_id, break; case RDMA_CM_EVENT_DISCONNECTED: + if (!conn) + break; rdsdebug("DISCONNECT event - dropping connection " "%pI6c->%pI6c\n", &conn->c_laddr, &conn->c_faddr); -- 2.17.0