[PATCH 3.16 217/305] IB/mlx4: Verify port number in flow steering create flow

[Ben Hutchings]

3.16.37-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Yishai Hadas <yishaih@xxxxxxxxxxxx>

commit 5533c18ab02b17a7f2ac11908e2d97d4b421617d upstream.

In procedure mlx4_ib_create_flow, passing an invalid port number
will cause an out-of-bounds array access. Data passed to this procedure
can come from user-space.  Therefore, need to validate port number
before proceeding onwards.

Note that we check against the number of physical ports declared at
the verbs (ib core) level; When bonding is active, the verbs level
sees one physical port, even though the low-level driver sees two ports.

Fixes: f77c0162a339 ("IB/mlx4: Add receive flow steering support")
Signed-off-by: Yishai Hadas <yishaih@xxxxxxxxxxxx>
Reviewed-by: Jack Morgenstein <jackm@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Moni Shoua <monis@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
[bwh: Backported to 3.16:
 - Adjust context
 - Function returns an integer, not a pointer/error]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/infiniband/hw/mlx4/main.c | 3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -1016,6 +1016,9 @@ static int __mlx4_ib_create_flow(struct
 		[IB_FLOW_DOMAIN_NIC] = MLX4_DOMAIN_NIC,
 	};
 
+	if (flow_attr->port < 1 || flow_attr->port > qp->device->phys_port_cnt)
+		return -EINVAL;
+
 	if (flow_attr->priority > MLX4_IB_FLOW_MAX_PRIO) {
 		pr_err("Invalid priority value %d\n", flow_attr->priority);
 		return -EINVAL;