[PATCH] vdpa/mlx5: fix param validation in mlx5_vdpa_get_config()

From: Stefano Garzarella
Date: Mon Feb 08 2021 - 13:35:01 EST


It's legal to have 'offset + len' equal to
sizeof(struct virtio_net_config), since 'ndev->config' is a
'struct virtio_net_config', so we can safely copy its content under
this condition.

Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
---
drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index dc88559a8d49..10e9b09932eb 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1820,7 +1820,7 @@ static void mlx5_vdpa_get_config(struct vdpa_device *vdev, unsigned int offset,
struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);

- if (offset + len < sizeof(struct virtio_net_config))
+ if (offset + len <= sizeof(struct virtio_net_config))
memcpy(buf, (u8 *)&ndev->config + offset, len);
}

--
2.29.2