Re: [PATCH] iscsi_tcp: fix the NULL pointer dereference

[michael.christie@oracle.com]

On 10/10/21 2:19 AM, Li Feng wrote:
>  drivers/scsi/iscsi_tcp.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
> index 1bc37593c88f..2ec1405d272d 100644
> --- a/drivers/scsi/iscsi_tcp.c
> +++ b/drivers/scsi/iscsi_tcp.c
> @@ -724,6 +724,8 @@ static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn,
>  		break;
>  	case ISCSI_PARAM_DATADGST_EN:
>  		iscsi_set_param(cls_conn, param, buf, buflen);
> +		if (!tcp_sw_conn || !tcp_sw_conn->sock)
> +			return -ENOTCONN;
>  		tcp_sw_conn->sendpage = conn->datadgst_en ?
>  			sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
>  		break;
> 

Hi,

Thanks for the patch. This was supposed to be fixed in:

commit 9e67600ed6b8565da4b85698ec659b5879a6c1c6
Author: Gulam Mohamed <gulam.mohamed@oracle.com>
Date:   Thu Mar 25 09:32:48 2021 +0000

    scsi: iscsi: Fix race condition between login and sync thread

because it was not supposed to allow set_param to be called on
an unbound connection. However, it looks like there was a mistake in
the patch:

                err = transport->set_param(conn, ev->u.set_param.param,
                                           data, ev->u.set_param.len);
+               if ((conn->state == ISCSI_CONN_BOUND) ||
+                       (conn->state == ISCSI_CONN_UP)) {
+                       err = transport->set_param(conn, ev->u.set_param.param,
+                                       data, ev->u.set_param.len);
+               } else {
+                       return -ENOTCONN;
+               }


and that first set_param call was supposed to be deleted and
replaced with the one that was added in the conn->state check.

We should just need a patch to remove that first set_param call.