From: Kamal Heib <kamalheib1@gmail.com>
Date: Fri, 27 Jul 2018 21:23:05 +0300
Subject: RDMA/core: Check for verbs callbacks before using them
Patch-mainline: v4.19-rc1
Git-commit: 0584c47bbc3b3149bfe544d4e090fb6d96addf6c
References: bsc#1103992 FATE#326009

Make sure the providers implement the verbs callbacks before calling
them, otherwise return -EOPNOTSUPP.

Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/core/uverbs_cmd.c |    3 ++-
 drivers/infiniband/core/verbs.c      |    3 +++
 2 files changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -2553,7 +2553,8 @@ ssize_t ib_uverbs_post_srq_recv(struct i
 		goto out;
 
 	resp.bad_wr = 0;
-	ret = srq->device->post_srq_recv(srq, wr, &bad_wr);
+	ret = srq->device->post_srq_recv ?
+		srq->device->post_srq_recv(srq, wr, &bad_wr) : -EOPNOTSUPP;
 
 	uobj_put_obj_read(srq);
 
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -479,6 +479,9 @@ static struct ib_ah *_rdma_create_ah(str
 {
 	struct ib_ah *ah;
 
+	if (!pd->device->create_ah)
+		return ERR_PTR(-EOPNOTSUPP);
+
 	ah = pd->device->create_ah(pd, ah_attr, udata);
 
 	if (!IS_ERR(ah)) {