net: rds: Fix possible null-pointer dereferences in rds_rdma_cm_event_handler_cmn()

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@gmail.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jia-Ju Bai 2019-07-26 22:17:05 +08:00 committed by David S. Miller
parent a0d57a552b
commit c7ba50fe23

View file

@ -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);