RDMA: Verify port when creating flow rule

Validate port value provided by the user and with that remove no longer
needed validation by the driver.  The missing check in the mlx5_ib driver
could cause to the below oops.

Call trace:
  _create_flow_rule+0x2d4/0xf28 [mlx5_ib]
  mlx5_ib_create_flow+0x2d0/0x5b0 [mlx5_ib]
  ib_uverbs_ex_create_flow+0x4cc/0x624 [ib_uverbs]
  ib_uverbs_handler_UVERBS_METHOD_INVOKE_WRITE+0xd4/0x150 [ib_uverbs]
  ib_uverbs_cmd_verbs.isra.7+0xb28/0xc50 [ib_uverbs]
  ib_uverbs_ioctl+0x158/0x1d0 [ib_uverbs]
  do_vfs_ioctl+0xd0/0xaf0
  ksys_ioctl+0x84/0xb4
  __arm64_sys_ioctl+0x28/0xc4
  el0_svc_common.constprop.3+0xa4/0x254
  el0_svc_handler+0x84/0xa0
  el0_svc+0x10/0x26c
 Code: b9401260 f9615681 51000400 8b001c20 (f9403c1a)

Fixes: 436f2ad ("IB/core: Export ib_create/destroy_flow through uverbs")
Link: https://lore.kernel.org/r/faad30dc5219a01727f47db3dc2f029d07c82c00.1623309971.git.leonro@nvidia.com
Reviewed-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/core/uverbs_cmd.c

@@ -3248,6 +3248,11 @@ static int ib_uverbs_ex_create_flow(struct uverbs_attr_bundle *attrs)
 		goto err_free_attr;
 	}
 
+	if (!rdma_is_port_valid(uobj->context->device, cmd.flow_attr.port)) {
+		err = -EINVAL;
+		goto err_uobj;
+	}
+
 	qp = uobj_get_obj_read(qp, UVERBS_OBJECT_QP, cmd.qp_handle, attrs);
 	if (!qp) {
 		err = -EINVAL;

drivers/infiniband/hw/mlx4/main.c

@@ -1699,9 +1699,6 @@ static struct ib_flow *mlx4_ib_create_flow(struct ib_qp *qp,
 	struct mlx4_dev *dev = (to_mdev(qp->device))->dev;
 	int is_bonded = mlx4_is_bonded(dev);
 
-	if (!rdma_is_port_valid(qp->device, flow_attr->port))
-		return ERR_PTR(-EINVAL);
-
 	if (flow_attr->flags & ~IB_FLOW_ATTR_FLAGS_DONT_TRAP)
 		return ERR_PTR(-EOPNOTSUPP);
 

drivers/infiniband/hw/mlx5/fs.c

@@ -1194,9 +1194,8 @@ static struct ib_flow *mlx5_ib_create_flow(struct ib_qp *qp,
 		goto free_ucmd;
 	}
 
-	if (flow_attr->port > dev->num_ports ||
-	    (flow_attr->flags &
-	     ~(IB_FLOW_ATTR_FLAGS_DONT_TRAP | IB_FLOW_ATTR_FLAGS_EGRESS))) {
+	if (flow_attr->flags &
+	    ~(IB_FLOW_ATTR_FLAGS_DONT_TRAP | IB_FLOW_ATTR_FLAGS_EGRESS)) {
 		err = -EINVAL;
 		goto free_ucmd;
 	}