Subject: [PATCH rdma-next 01/12] RDMA/uverbs: Protect from attempts to create flows on unsupported QP

From: Leon Romanovsky <[email-masked]>
Date: Sun, 24 Jun 2018 11:23:42 +0300

From: Leon Romanovsky <[email-masked]>

Flows can be created on UD and RAW_PACKET QP types. Attempts to provide
other QP types as an input causes to various unpredictable failures.

The reason to it that in order to support all various types (e.g. XRC),
we are supposed to use real_qp handle and not qp handle and give to
driver/FW to fail such (XRC) flows. Being valuable solution, the simpler
and safer variant is to ban all QP types except UD and RAW_PACKET,
instead of relying on driver/FW.

Cc: <[email-masked]> # 3.11
Fixes: 436f2ad05a0b ("IB/core: Export ib_create/destroy_flow through uverbs")
Cc: syzkaller <[email-masked]>
Reported-by: Noa Osherovich <[email-masked]>
Signed-off-by: Leon Romanovsky <[email-masked]>
---
 drivers/infiniband/core/uverbs_cmd.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 779892b63729..c842a9423fbf 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -3553,14 +3553,20 @@ int ib_uverbs_ex_create_flow(struct ib_uverbs_file *file,
 		goto err_free_attr;
 	}
 
-	qp = uobj_get_obj_read(qp, UVERBS_OBJECT_QP, cmd.qp_handle, file->ucontext);
+	qp = uobj_get_obj_read(qp, UVERBS_OBJECT_QP, cmd.qp_handle,
+			       file->ucontext);
 	if (!qp) {
 		err = -EINVAL;
 		goto err_uobj;
 	}
 
+	if (qp->qp_type != IB_QPT_UD && qp->qp_type != IB_QPT_RAW_PACKET) {
+		err = -EINVAL;
+		goto err_put;
+	}
+
 	flow_attr = kzalloc(struct_size(flow_attr, flows,
-				cmd.flow_attr.num_of_specs), GFP_KERNEL);
+					cmd.flow_attr.num_of_specs), GFP_KERNEL);
 	if (!flow_attr) {
 		err = -ENOMEM;
 		goto err_put;
-- 
2.14.4