[PATCH] scsi: iscsi_tcp: Check the sock is correct before iscsi_set_param

From: Zhong Jinghua
Date: Wed Mar 29 2023 - 03:18:18 EST


From: Zhong Jinghua <zhongjinghua@xxxxxxxxxx>

The correctness of sock should be checked before assignment to avoid
assigning wrong values.

Commit
"scsi: iscsi: iscsi_tcp: Fix null-ptr-deref while calling getpeername()"
introduced this change. This change may lead to inconsistent values of
tcp_sw_conn->sendpage and conn->datadgst_en.

Fix it by moving the position of the assignment.

Fixes: 57569c37f0ad ("scsi: iscsi: iscsi_tcp: Fix null-ptr-deref while calling getpeername()")
Signed-off-by: Zhong Jinghua <zhongjinghua@xxxxxxxxxx>
---
drivers/scsi/iscsi_tcp.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 882e8b81b490..b32f3ca3e7d0 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -726,13 +726,12 @@ static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn,
iscsi_set_param(cls_conn, param, buf, buflen);
break;
case ISCSI_PARAM_DATADGST_EN:
- iscsi_set_param(cls_conn, param, buf, buflen);
-
mutex_lock(&tcp_sw_conn->sock_lock);
if (!tcp_sw_conn->sock) {
mutex_unlock(&tcp_sw_conn->sock_lock);
return -ENOTCONN;
}
+ iscsi_set_param(cls_conn, param, buf, buflen);
tcp_sw_conn->sendpage = conn->datadgst_en ?
sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
mutex_unlock(&tcp_sw_conn->sock_lock);
--
2.31.1