On 2022/3/3 22:59, Mike Christie wrote:
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?
It's from code review. I reviewed the code because the panic mentioned
in my first patch. The issue seems would not happen, so just ignore it.
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.
.
