On 3/3/22 8:56 PM, Wenchao Hao wrote:
> iscsi_create_conn() would add newly alloced iscsi_cls_conn to connlist,
> it means when userspace sends ISCSI_UEVENT_SET_PARAM, iscsi_conn_lookup()
> would found this iscsi_cls_conn and call the set_param callback which is
> iscsi_sw_tcp_conn_set_param(). While the iscsi_conn's dd_data might not
> been initialized.
>
> Signed-off-by: Wenchao Hao <haowenchao@xxxxxxxxxx>
> Signed-off-by: Wu Bo <wubo40@xxxxxxxxxx>
> ---
> drivers/scsi/iscsi_tcp.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
> index 14db224486be..a42449df6156 100644
> --- a/drivers/scsi/iscsi_tcp.c
> +++ b/drivers/scsi/iscsi_tcp.c
> @@ -716,13 +716,17 @@ static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn,
> {
> struct iscsi_conn *conn = cls_conn->dd_data;
> struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
> - struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
> + struct iscsi_sw_tcp_conn *tcp_sw_conn;
>
> switch(param) {
> case ISCSI_PARAM_HDRDGST_EN:
> iscsi_set_param(cls_conn, param, buf, buflen);
> break;
> case ISCSI_PARAM_DATADGST_EN:
> + if (!tcp_conn || !tcp_conn->dd_data)
> + return -ENOTCONN;
> +
> + tcp_sw_conn = tcp_conn->dd_data;
> iscsi_set_param(cls_conn, param, buf, buflen);
> tcp_sw_conn->sendpage = conn->datadgst_en ?
> sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
Is this something you hit or from code review?
We have those state checks:
if ((conn->state == ISCSI_CONN_BOUND) ||
(conn->state == ISCSI_CONN_UP)) {
err = transport->set_param(conn, ev->u.set_param.param,
so we don't call set_param until after we have bound the
connection which will be after ISCSI_UEVENT_CREATE_CONN has returned.
Also for this specific bug iscsi_if_recv_msg is called with the
rx_queue_mutex, so set_param can only be called after the
ISCSI_UEVENT_CREATE_CONN cmd has returned.
