From: David Ahern <dsahern@kernel•org>
To: netdev@vger•kernel.org
Cc: davem@davemloft•net, kuba@kernel•org, brouer@redhat•com,
toke@redhat•com, daniel@iogearbox•net, john.fastabend@gmail•com,
ast@kernel•org, kafai@fb•com, songliubraving@fb•com, yhs@fb•com,
andriin@fb•com, dsahern@gmail•com
Subject: [PATCH v2 bpf-next 1/5] devmap: Formalize map value as a named struct
Date: Wed, 27 May 2020 18:14:19 -0600 [thread overview]
Message-ID: <20200528001423.58575-2-dsahern@kernel.org> (raw)
In-Reply-To: <20200528001423.58575-1-dsahern@kernel.org>
From: David Ahern <dsahern@gmail•com>
Add 'struct devmap_val' to the bpf uapi to formalize the
expected values that can be passed in for a DEVMAP.
Update devmap code to use the struct.
Signed-off-by: David Ahern <dsahern@gmail•com>
---
include/uapi/linux/bpf.h | 5 ++++
kernel/bpf/devmap.c | 43 ++++++++++++++++++++--------------
tools/include/uapi/linux/bpf.h | 5 ++++
3 files changed, 35 insertions(+), 18 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 54b93f8b49b8..d27302ecaa9c 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -3625,6 +3625,11 @@ struct xdp_md {
__u32 rx_queue_index; /* rxq->queue_index */
};
+/* DEVMAP values */
+struct devmap_val {
+ __u32 ifindex; /* device index */
+};
+
enum sk_action {
SK_DROP = 0,
SK_PASS,
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index a51d9fb7a359..069a50113e26 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -66,6 +66,7 @@ struct bpf_dtab_netdev {
struct bpf_dtab *dtab;
struct rcu_head rcu;
unsigned int idx;
+ struct devmap_val val;
};
struct bpf_dtab {
@@ -110,7 +111,8 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
/* check sanity of attributes */
if (attr->max_entries == 0 || attr->key_size != 4 ||
- attr->value_size != 4 || attr->map_flags & ~DEV_CREATE_FLAG_MASK)
+ attr->value_size > sizeof(struct devmap_val) ||
+ attr->map_flags & ~DEV_CREATE_FLAG_MASK)
return -EINVAL;
/* Lookup returns a pointer straight to dev->ifindex, so make sure the
@@ -472,18 +474,15 @@ int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb,
static void *dev_map_lookup_elem(struct bpf_map *map, void *key)
{
struct bpf_dtab_netdev *obj = __dev_map_lookup_elem(map, *(u32 *)key);
- struct net_device *dev = obj ? obj->dev : NULL;
- return dev ? &dev->ifindex : NULL;
+ return obj ? &obj->val : NULL;
}
static void *dev_map_hash_lookup_elem(struct bpf_map *map, void *key)
{
struct bpf_dtab_netdev *obj = __dev_map_hash_lookup_elem(map,
*(u32 *)key);
- struct net_device *dev = obj ? obj->dev : NULL;
-
- return dev ? &dev->ifindex : NULL;
+ return obj ? &obj->val : NULL;
}
static void __dev_map_entry_free(struct rcu_head *rcu)
@@ -541,7 +540,7 @@ static int dev_map_hash_delete_elem(struct bpf_map *map, void *key)
static struct bpf_dtab_netdev *__dev_map_alloc_node(struct net *net,
struct bpf_dtab *dtab,
- u32 ifindex,
+ struct devmap_val *val,
unsigned int idx)
{
struct bpf_dtab_netdev *dev;
@@ -551,16 +550,18 @@ static struct bpf_dtab_netdev *__dev_map_alloc_node(struct net *net,
if (!dev)
return ERR_PTR(-ENOMEM);
- dev->dev = dev_get_by_index(net, ifindex);
- if (!dev->dev) {
- kfree(dev);
- return ERR_PTR(-EINVAL);
- }
+ dev->dev = dev_get_by_index(net, val->ifindex);
+ if (!dev->dev)
+ goto err_out;
dev->idx = idx;
dev->dtab = dtab;
+ dev->val.ifindex = val->ifindex;
return dev;
+err_out:
+ kfree(dev);
+ return ERR_PTR(-EINVAL);
}
static int __dev_map_update_elem(struct net *net, struct bpf_map *map,
@@ -568,7 +569,7 @@ static int __dev_map_update_elem(struct net *net, struct bpf_map *map,
{
struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
struct bpf_dtab_netdev *dev, *old_dev;
- u32 ifindex = *(u32 *)value;
+ struct devmap_val val = { };
u32 i = *(u32 *)key;
if (unlikely(map_flags > BPF_EXIST))
@@ -578,10 +579,13 @@ static int __dev_map_update_elem(struct net *net, struct bpf_map *map,
if (unlikely(map_flags == BPF_NOEXIST))
return -EEXIST;
- if (!ifindex) {
+ /* already verified value_size <= sizeof val */
+ memcpy(&val, value, map->value_size);
+
+ if (!val.ifindex) {
dev = NULL;
} else {
- dev = __dev_map_alloc_node(net, dtab, ifindex, i);
+ dev = __dev_map_alloc_node(net, dtab, &val, i);
if (IS_ERR(dev))
return PTR_ERR(dev);
}
@@ -609,12 +613,15 @@ static int __dev_map_hash_update_elem(struct net *net, struct bpf_map *map,
{
struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
struct bpf_dtab_netdev *dev, *old_dev;
- u32 ifindex = *(u32 *)value;
+ struct devmap_val val = { };
u32 idx = *(u32 *)key;
unsigned long flags;
int err = -EEXIST;
- if (unlikely(map_flags > BPF_EXIST || !ifindex))
+ /* already verified value_size <= sizeof val */
+ memcpy(&val, value, map->value_size);
+
+ if (unlikely(map_flags > BPF_EXIST || !val.ifindex))
return -EINVAL;
spin_lock_irqsave(&dtab->index_lock, flags);
@@ -623,7 +630,7 @@ static int __dev_map_hash_update_elem(struct net *net, struct bpf_map *map,
if (old_dev && (map_flags & BPF_NOEXIST))
goto out_err;
- dev = __dev_map_alloc_node(net, dtab, ifindex, idx);
+ dev = __dev_map_alloc_node(net, dtab, &val, idx);
if (IS_ERR(dev)) {
err = PTR_ERR(dev);
goto out_err;
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 54b93f8b49b8..d27302ecaa9c 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -3625,6 +3625,11 @@ struct xdp_md {
__u32 rx_queue_index; /* rxq->queue_index */
};
+/* DEVMAP values */
+struct devmap_val {
+ __u32 ifindex; /* device index */
+};
+
enum sk_action {
SK_DROP = 0,
SK_PASS,
--
2.21.1 (Apple Git-122.3)
next prev parent reply other threads:[~2020-05-28 0:14 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-28 0:14 [PATCH v2 bpf-next 0/5] bpf: Add support for XDP programs in DEVMAP entries David Ahern
2020-05-28 0:14 ` David Ahern [this message]
2020-05-28 7:01 ` [PATCH v2 bpf-next 1/5] devmap: Formalize map value as a named struct Andrii Nakryiko
2020-05-28 22:37 ` David Ahern
2020-05-28 0:14 ` [PATCH v2 bpf-next 2/5] bpf: Add support to attach bpf program to a devmap entry David Ahern
2020-05-28 7:01 ` Andrii Nakryiko
2020-05-28 22:40 ` David Ahern
2020-05-28 22:54 ` Andrii Nakryiko
2020-05-28 8:54 ` Toke Høiland-Jørgensen
2020-05-28 0:14 ` [PATCH v2 bpf-next 3/5] xdp: Add xdp_txq_info to xdp_buff David Ahern
2020-05-28 0:14 ` [PATCH v2 bpf-next 4/5] libbpf: Add SEC name for xdp programs attached to device map David Ahern
2020-05-28 7:04 ` Andrii Nakryiko
2020-05-28 22:49 ` David Ahern
2020-05-28 0:14 ` [PATCH v2 bpf-next 5/5] selftest: Add tests for XDP programs in devmap entries David Ahern
2020-05-28 7:08 ` Andrii Nakryiko
2020-05-28 10:25 ` Jesper Dangaard Brouer
2020-05-28 22:56 ` David Ahern
2020-05-28 22:54 ` David Ahern
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200528001423.58575-2-dsahern@kernel.org \
--to=dsahern@kernel$(echo .)org \
--cc=andriin@fb$(echo .)com \
--cc=ast@kernel$(echo .)org \
--cc=brouer@redhat$(echo .)com \
--cc=daniel@iogearbox$(echo .)net \
--cc=davem@davemloft$(echo .)net \
--cc=dsahern@gmail$(echo .)com \
--cc=john.fastabend@gmail$(echo .)com \
--cc=kafai@fb$(echo .)com \
--cc=kuba@kernel$(echo .)org \
--cc=netdev@vger$(echo .)kernel.org \
--cc=songliubraving@fb$(echo .)com \
--cc=toke@redhat$(echo .)com \
--cc=yhs@fb$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox