[PATCH V3 1/6] vDPA/ifcvf: get_config_size should return a value no greater than dev implementation
From: Zhu Lingshan <hidden>
Date: 2022-07-01 13:36:18
Subsystem:
intel virtio data path accelerator, the rest, virtio core · Maintainers:
Zhu Lingshan, Linus Torvalds, "Michael S. Tsirkin", Jason Wang
ifcvf_get_config_size() should return a virtio device type specific value, however the ret_value should not be greater than the onboard size of the device implementation. E.g., for virtio_net, config_size should be the minimum value of sizeof(struct virtio_net_config) and the onboard cap size. Signed-off-by: Zhu Lingshan <redacted> --- drivers/vdpa/ifcvf/ifcvf_base.c | 13 +++++++++++-- drivers/vdpa/ifcvf/ifcvf_base.h | 2 ++ 2 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/vdpa/ifcvf/ifcvf_base.c b/drivers/vdpa/ifcvf/ifcvf_base.c
index 48c4dadb0c7c..fb957b57941e 100644
--- a/drivers/vdpa/ifcvf/ifcvf_base.c
+++ b/drivers/vdpa/ifcvf/ifcvf_base.c@@ -128,6 +128,7 @@ int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *pdev) break; case VIRTIO_PCI_CAP_DEVICE_CFG: hw->dev_cfg = get_cap_addr(hw, &cap); + hw->cap_dev_config_size = le32_to_cpu(cap.length); IFCVF_DBG(pdev, "hw->dev_cfg = %p\n", hw->dev_cfg); break; }
@@ -233,15 +234,23 @@ int ifcvf_verify_min_features(struct ifcvf_hw *hw, u64 features) u32 ifcvf_get_config_size(struct ifcvf_hw *hw) { struct ifcvf_adapter *adapter; + u32 net_config_size = sizeof(struct virtio_net_config); + u32 blk_config_size = sizeof(struct virtio_blk_config); + u32 cap_size = hw->cap_dev_config_size; u32 config_size; adapter = vf_to_adapter(hw); + /* If the onboard device config space size is greater than + * the size of struct virtio_net/blk_config, only the spec + * implementing contents size is returned, this is very + * unlikely, defensive programming. + */ switch (hw->dev_type) { case VIRTIO_ID_NET: - config_size = sizeof(struct virtio_net_config); + config_size = cap_size >= net_config_size ? net_config_size : cap_size; break; case VIRTIO_ID_BLOCK: - config_size = sizeof(struct virtio_blk_config); + config_size = cap_size >= blk_config_size ? blk_config_size : cap_size; break; default: config_size = 0;
diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h b/drivers/vdpa/ifcvf/ifcvf_base.h
index 115b61f4924b..f5563f665cc6 100644
--- a/drivers/vdpa/ifcvf/ifcvf_base.h
+++ b/drivers/vdpa/ifcvf/ifcvf_base.h@@ -87,6 +87,8 @@ struct ifcvf_hw { int config_irq; int vqs_reused_irq; u16 nr_vring; + /* VIRTIO_PCI_CAP_DEVICE_CFG size */ + u32 cap_dev_config_size; }; struct ifcvf_adapter {
--
2.31.1