[PATCH] IB/srpt: Fix a potential null pointer dereference

[Jing Xiangfeng]

In srpt_cm_req_recv(), it is possible that sdev is NULL,
so we should test sdev before using it.

Signed-off-by: Jing Xiangfeng <jingxiangfeng@xxxxxxxxxx>
---
 drivers/infiniband/ulp/srpt/ib_srpt.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index 98552749d71c..72053254bf84 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -2143,7 +2143,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
 			    const struct srp_login_req *req,
 			    const char *src_addr)
 {
-	struct srpt_port *sport = &sdev->port[port_num - 1];
+	struct srpt_port *sport;
 	struct srpt_nexus *nexus;
 	struct srp_login_rsp *rsp = NULL;
 	struct srp_login_rej *rej = NULL;
@@ -2162,6 +2162,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
 	if (WARN_ON(!sdev || !req))
 		return -EINVAL;
 
+	sport = &sdev->port[port_num - 1];
 	it_iu_len = be32_to_cpu(req->req_it_iu_len);
 
 	pr_info("Received SRP_LOGIN_REQ with i_port_id %pI6, t_port_id %pI6 and it_iu_len %d on port %d (guid=%pI6); pkey %#04x\n",
-- 
2.17.1