Re: [PATCH net-next v5 05/12] virtio_net: Query and set flow filter caps
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: 2025-10-21 13:19:06
Also in:
virtualization
On Thu, Oct 16, 2025 at 12:00:48AM -0500, Daniel Jurgens wrote:
+ /* VIRTIO_NET_FF_MASK_TYPE start at 1 */ + for (i = 1; i <= VIRTIO_NET_FF_MASK_TYPE_MAX; i++) + ff_mask_size += get_mask_size(i); + + ff->ff_mask = kzalloc(ff_mask_size, GFP_KERNEL); + if (!ff->ff_mask) + goto err_ff; + + err = virtio_admin_cap_get(vdev, + VIRTIO_NET_FF_SELECTOR_CAP, + ff->ff_mask, + ff_mask_size); + + if (err) + goto err_ff_mask; + + ff->ff_actions = kzalloc(sizeof(*ff->ff_actions) + + VIRTIO_NET_FF_ACTION_MAX, + GFP_KERNEL); + if (!ff->ff_actions) + goto err_ff_mask; + + err = virtio_admin_cap_get(vdev, + VIRTIO_NET_FF_ACTION_CAP, + ff->ff_actions, + sizeof(*ff->ff_actions) + VIRTIO_NET_FF_ACTION_MAX); + + if (err) + goto err_ff_action; + + err = virtio_admin_cap_set(vdev, + VIRTIO_NET_FF_RESOURCE_CAP, + ff->ff_caps, + sizeof(*ff->ff_caps)); + if (err) + goto err_ff_action; + + ff_mask_size = sizeof(struct virtio_net_ff_cap_mask_data);
overriding ff_mask_size seems unncessarily funky. use a variable reflecting what this is?
+ sel = &ff->ff_mask->selectors[0];
+
+ for (i = 0; i < ff->ff_mask->count; i++) {
+ if (sel->length > MAX_SEL_LEN) {
+ err = -EINVAL;
+ goto err_ff_action;
+ }You also need to validate this is all within allocated size.
+ ff_mask_size += sizeof(struct virtio_net_ff_selector) + sel->length; + sel = (void *)sel + sizeof(*sel) + sel->length;
quoted hunk ↗ jump to hunk
+ } + + err = virtio_admin_cap_set(vdev, + VIRTIO_NET_FF_SELECTOR_CAP, + ff->ff_mask, + ff_mask_size); + if (err) + goto err_ff_action; + + err = virtio_admin_cap_set(vdev, + VIRTIO_NET_FF_ACTION_CAP, + ff->ff_actions, + sizeof(*ff->ff_actions) + VIRTIO_NET_FF_ACTION_MAX); + if (err) + goto err_ff_action; + + ff->vdev = vdev; + ff->ff_supported = true; + + kfree(cap_id_list); + + return; + +err_ff_action: + kfree(ff->ff_actions); +err_ff_mask: + kfree(ff->ff_mask); +err_ff: + kfree(ff->ff_caps); +err_cap_list: + kfree(cap_id_list); +} + +static void virtnet_ff_cleanup(struct virtnet_ff *ff) +{ + if (!ff->ff_supported) + return; + + kfree(ff->ff_actions); + kfree(ff->ff_mask); + kfree(ff->ff_caps); +} + static int virtnet_probe(struct virtio_device *vdev) { int i, err = -ENOMEM;@@ -7116,6 +7277,8 @@ static int virtnet_probe(struct virtio_device *vdev) } vi->guest_offloads_capable = vi->guest_offloads; + virtnet_ff_init(&vi->ff, vi->vdev); + rtnl_unlock(); err = virtnet_cpu_notif_add(vi);@@ -7131,6 +7294,7 @@ static int virtnet_probe(struct virtio_device *vdev) free_unregister_netdev: unregister_netdev(dev); + virtnet_ff_cleanup(&vi->ff); free_failover: net_failover_destroy(vi->failover); free_vqs:@@ -7180,6 +7344,7 @@ static void virtnet_remove(struct virtio_device *vdev) virtnet_free_irq_moder(vi); unregister_netdev(vi->dev); + virtnet_ff_cleanup(&vi->ff); net_failover_destroy(vi->failover);diff --git a/include/linux/virtio_admin.h b/include/linux/virtio_admin.h index 039b996f73ec..db0f42346ca9 100644 --- a/include/linux/virtio_admin.h +++ b/include/linux/virtio_admin.h@@ -3,6 +3,7 @@ * Header file for virtio admin operations */ #include <uapi/linux/virtio_pci.h> +#include <uapi/linux/virtio_net_ff.h> #ifndef _LINUX_VIRTIO_ADMIN_H #define _LINUX_VIRTIO_ADMIN_Hdiff --git a/include/uapi/linux/virtio_net_ff.h b/include/uapi/linux/virtio_net_ff.h new file mode 100644 index 000000000000..1a4738889403 --- /dev/null +++ b/include/uapi/linux/virtio_net_ff.h@@ -0,0 +1,91 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note + * + * Header file for virtio_net flow filters + */ +#ifndef _LINUX_VIRTIO_NET_FF_H +#define _LINUX_VIRTIO_NET_FF_H + +#include <linux/types.h> +#include <linux/kernel.h> + +#define VIRTIO_NET_FF_RESOURCE_CAP 0x800 +#define VIRTIO_NET_FF_SELECTOR_CAP 0x801 +#define VIRTIO_NET_FF_ACTION_CAP 0x802 + +/** + * struct virtio_net_ff_cap_data - Flow filter resource capability limits + * @groups_limit: maximum number of flow filter groups supported by the device + * @classifiers_limit: maximum number of classifiers supported by the device + * @rules_limit: maximum number of rules supported device-wide across all groups + * @rules_per_group_limit: maximum number of rules allowed in a single group + * @last_rule_priority: priority value associated with the lowest-priority rule + * @selectors_per_classifier_limit: maximum selectors allowed in one classifier + * + * The limits are reported by the device and describe resource capacities for + * flow filters. Multi-byte fields are little-endian. + */ +struct virtio_net_ff_cap_data { + __le32 groups_limit; + __le32 classifiers_limit; + __le32 rules_limit; + __le32 rules_per_group_limit; + __u8 last_rule_priority; + __u8 selectors_per_classifier_limit; +}; + +/** + * struct virtio_net_ff_selector - Selector mask descriptor + * @type: selector type, one of VIRTIO_NET_FF_MASK_TYPE_* constants + * @flags: selector flags, see VIRTIO_NET_FF_MASK_F_* constants + * @reserved: must be set to 0 by the driver and ignored by the device + * @length: size in bytes of @mask + * @reserved1: must be set to 0 by the driver and ignored by the device + * @mask: variable-length mask payload for @type, length given by @length + * + * A selector describes a header mask that a classifier can apply. The format + * of @mask depends on @type. + */ +struct virtio_net_ff_selector { + __u8 type; + __u8 flags; + __u8 reserved[2]; + __u8 length; + __u8 reserved1[3]; + __u8 mask[]; +}; + +#define VIRTIO_NET_FF_MASK_TYPE_ETH 1 +#define VIRTIO_NET_FF_MASK_TYPE_IPV4 2 +#define VIRTIO_NET_FF_MASK_TYPE_IPV6 3 +#define VIRTIO_NET_FF_MASK_TYPE_TCP 4 +#define VIRTIO_NET_FF_MASK_TYPE_UDP 5 +#define VIRTIO_NET_FF_MASK_TYPE_MAX VIRTIO_NET_FF_MASK_TYPE_UDP + +/** + * struct virtio_net_ff_cap_mask_data - Supported selector mask formats + * @count: number of entries in @selectors + * @reserved: must be set to 0 by the driver and ignored by the device + * @selectors: array of supported selector descriptors + */ +struct virtio_net_ff_cap_mask_data { + __u8 count; + __u8 reserved[7]; + struct virtio_net_ff_selector selectors[]; +}; +#define VIRTIO_NET_FF_MASK_F_PARTIAL_MASK (1 << 0) + +#define VIRTIO_NET_FF_ACTION_DROP 1 +#define VIRTIO_NET_FF_ACTION_RX_VQ 2 +#define VIRTIO_NET_FF_ACTION_MAX VIRTIO_NET_FF_ACTION_RX_VQ +/** + * struct virtio_net_ff_actions - Supported flow actions + * @count: number of supported actions in @actions + * @reserved: must be set to 0 by the driver and ignored by the device + * @actions: array of action identifiers (VIRTIO_NET_FF_ACTION_*) + */ +struct virtio_net_ff_actions { + __u8 count; + __u8 reserved[7]; + __u8 actions[]; +}; +#endif-- 2.50.1