Re: [PATCH v3 08/13] vdpa: add return value to get_config/set_config callbacks
From: Stefano Garzarella
Date: Fri Feb 05 2021 - 03:50:45 EST
Adding Eli in the loop.
On Fri, Feb 05, 2021 at 11:20:11AM +0800, Jason Wang wrote:
On 2021/2/5 上午1:22, Stefano Garzarella wrote:
All implementations of these callbacks already validate inputs.
Let's return an error from these callbacks, so the caller doesn't
need to validate the input anymore.
We update all implementations to return -EINVAL in case of invalid
input.
Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
---
include/linux/vdpa.h | 18 ++++++++++--------
drivers/vdpa/ifcvf/ifcvf_main.c | 24 ++++++++++++++++--------
drivers/vdpa/mlx5/net/mlx5_vnet.c | 17 +++++++++++------
drivers/vdpa/vdpa_sim/vdpa_sim.c | 16 ++++++++++------
4 files changed, 47 insertions(+), 28 deletions(-)
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 4ab5494503a8..0e0cbd5fb41b 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -157,6 +157,7 @@ struct vdpa_iova_range {
* @buf: buffer used to read to
* @len: the length to read from
* configuration space
+ * Returns integer: success (0) or error (< 0)
* @set_config: Write to device specific configuration space
* @vdev: vdpa device
* @offset: offset from the beginning of
@@ -164,6 +165,7 @@ struct vdpa_iova_range {
* @buf: buffer used to write from
* @len: the length to write to
* configuration space
+ * Returns integer: success (0) or error (< 0)
* @get_generation: Get device config generation (optional)
* @vdev: vdpa device
* Returns u32: device generation
@@ -231,10 +233,10 @@ struct vdpa_config_ops {
u32 (*get_vendor_id)(struct vdpa_device *vdev);
u8 (*get_status)(struct vdpa_device *vdev);
void (*set_status)(struct vdpa_device *vdev, u8 status);
- void (*get_config)(struct vdpa_device *vdev, unsigned int offset,
- void *buf, unsigned int len);
- void (*set_config)(struct vdpa_device *vdev, unsigned int offset,
- const void *buf, unsigned int len);
+ int (*get_config)(struct vdpa_device *vdev, unsigned int offset,
+ void *buf, unsigned int len);
+ int (*set_config)(struct vdpa_device *vdev, unsigned int offset,
+ const void *buf, unsigned int len);
u32 (*get_generation)(struct vdpa_device *vdev);
struct vdpa_iova_range (*get_iova_range)(struct vdpa_device *vdev);
@@ -329,8 +331,8 @@ static inline int vdpa_set_features(struct vdpa_device *vdev, u64 features)
}
-static inline void vdpa_get_config(struct vdpa_device *vdev, unsigned offset,
- void *buf, unsigned int len)
+static inline int vdpa_get_config(struct vdpa_device *vdev, unsigned offset,
+ void *buf, unsigned int len)
{
const struct vdpa_config_ops *ops = vdev->config;
@@ -339,8 +341,8 @@ static inline void vdpa_get_config(struct vdpa_device *vdev, unsigned offset,
* If it does happen we assume a legacy guest.
*/
if (!vdev->features_valid)
- vdpa_set_features(vdev, 0);
- ops->get_config(vdev, offset, buf, len);
+ return vdpa_set_features(vdev, 0);
+ return ops->get_config(vdev, offset, buf, len);
}
/**
diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index 7c8bbfcf6c3e..f5e6a90d8114 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -332,24 +332,32 @@ static u32 ifcvf_vdpa_get_vq_align(struct vdpa_device *vdpa_dev)
return IFCVF_QUEUE_ALIGNMENT;
}
-static void ifcvf_vdpa_get_config(struct vdpa_device *vdpa_dev,
- unsigned int offset,
- void *buf, unsigned int len)
+static int ifcvf_vdpa_get_config(struct vdpa_device *vdpa_dev,
+ unsigned int offset,
+ void *buf, unsigned int len)
{
struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
- WARN_ON(offset + len > sizeof(struct virtio_net_config));
+ if (offset + len > sizeof(struct virtio_net_config))
+ return -EINVAL;
+
ifcvf_read_net_config(vf, offset, buf, len);
+
+ return 0;
}
-static void ifcvf_vdpa_set_config(struct vdpa_device *vdpa_dev,
- unsigned int offset, const void *buf,
- unsigned int len)
+static int ifcvf_vdpa_set_config(struct vdpa_device *vdpa_dev,
+ unsigned int offset, const void *buf,
+ unsigned int len)
{
struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
- WARN_ON(offset + len > sizeof(struct virtio_net_config));
+ if (offset + len > sizeof(struct virtio_net_config))
+ return -EINVAL;
+
ifcvf_write_net_config(vf, offset, buf, len);
+
+ return 0;
}
static void ifcvf_vdpa_set_config_cb(struct vdpa_device *vdpa_dev,
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 029822060017..9323b5ff7988 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1796,20 +1796,25 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status)
ndev->mvdev.status |= VIRTIO_CONFIG_S_FAILED;
}
-static void mlx5_vdpa_get_config(struct vdpa_device *vdev, unsigned int offset, void *buf,
- unsigned int len)
+static int mlx5_vdpa_get_config(struct vdpa_device *vdev, unsigned int offset, void *buf,
+ unsigned int len)
{
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))
- memcpy(buf, (u8 *)&ndev->config + offset, len);
+ if (offset + len > sizeof(struct virtio_net_config))
+ return -EINVAL;
It looks to me we should use ">=" here?
Ehmm, I think it was wrong before this patch. If 'offset + len' is equal
to 'sizeof(struct virtio_net_config)', should be okay to copy, no?
I think it's one of the rare cases where the copy and paste went well
:-)
Should I fix this in a separate patch?
Thanks,
Stefano