/*
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* Copyright (C) 2017-2018 Netronome Systems, Inc.
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*
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* This software is licensed under the GNU General License Version 2,
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* June 1991 as shown in the file COPYING in the top-level directory of this
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* source tree.
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*
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* THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
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* WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
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* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
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* OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
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* THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
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*/
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|
#include <linux/bpf.h>
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#include <linux/bpf_verifier.h>
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#include <linux/bug.h>
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#include <linux/kdev_t.h>
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#include <linux/list.h>
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#include <linux/lockdep.h>
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#include <linux/netdevice.h>
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#include <linux/printk.h>
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#include <linux/proc_ns.h>
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#include <linux/rhashtable.h>
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#include <linux/rtnetlink.h>
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#include <linux/rwsem.h>
|
|
/* Protects offdevs, members of bpf_offload_netdev and offload members
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* of all progs.
|
* RTNL lock cannot be taken when holding this lock.
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*/
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static DECLARE_RWSEM(bpf_devs_lock);
|
|
struct bpf_offload_dev {
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const struct bpf_prog_offload_ops *ops;
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struct list_head netdevs;
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void *priv;
|
};
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|
struct bpf_offload_netdev {
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struct rhash_head l;
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struct net_device *netdev;
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struct bpf_offload_dev *offdev;
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struct list_head progs;
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struct list_head maps;
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struct list_head offdev_netdevs;
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};
|
|
static const struct rhashtable_params offdevs_params = {
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.nelem_hint = 4,
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.key_len = sizeof(struct net_device *),
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.key_offset = offsetof(struct bpf_offload_netdev, netdev),
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.head_offset = offsetof(struct bpf_offload_netdev, l),
|
.automatic_shrinking = true,
|
};
|
|
static struct rhashtable offdevs;
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static bool offdevs_inited;
|
|
static int bpf_dev_offload_check(struct net_device *netdev)
|
{
|
if (!netdev)
|
return -EINVAL;
|
if (!netdev->netdev_ops->ndo_bpf)
|
return -EOPNOTSUPP;
|
return 0;
|
}
|
|
static struct bpf_offload_netdev *
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bpf_offload_find_netdev(struct net_device *netdev)
|
{
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lockdep_assert_held(&bpf_devs_lock);
|
|
if (!offdevs_inited)
|
return NULL;
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return rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params);
|
}
|
|
int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr)
|
{
|
struct bpf_offload_netdev *ondev;
|
struct bpf_prog_offload *offload;
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int err;
|
|
if (attr->prog_type != BPF_PROG_TYPE_SCHED_CLS &&
|
attr->prog_type != BPF_PROG_TYPE_XDP)
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return -EINVAL;
|
|
if (attr->prog_flags)
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return -EINVAL;
|
|
offload = kzalloc(sizeof(*offload), GFP_USER);
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if (!offload)
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return -ENOMEM;
|
|
offload->prog = prog;
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|
offload->netdev = dev_get_by_index(current->nsproxy->net_ns,
|
attr->prog_ifindex);
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err = bpf_dev_offload_check(offload->netdev);
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if (err)
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goto err_maybe_put;
|
|
down_write(&bpf_devs_lock);
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ondev = bpf_offload_find_netdev(offload->netdev);
|
if (!ondev) {
|
err = -EINVAL;
|
goto err_unlock;
|
}
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offload->offdev = ondev->offdev;
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prog->aux->offload = offload;
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list_add_tail(&offload->offloads, &ondev->progs);
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dev_put(offload->netdev);
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up_write(&bpf_devs_lock);
|
|
return 0;
|
err_unlock:
|
up_write(&bpf_devs_lock);
|
err_maybe_put:
|
if (offload->netdev)
|
dev_put(offload->netdev);
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kfree(offload);
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return err;
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}
|
|
int bpf_prog_offload_verifier_prep(struct bpf_prog *prog)
|
{
|
struct bpf_prog_offload *offload;
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int ret = -ENODEV;
|
|
down_read(&bpf_devs_lock);
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offload = prog->aux->offload;
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if (offload) {
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ret = offload->offdev->ops->prepare(prog);
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offload->dev_state = !ret;
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}
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up_read(&bpf_devs_lock);
|
|
return ret;
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}
|
|
int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env,
|
int insn_idx, int prev_insn_idx)
|
{
|
struct bpf_prog_offload *offload;
|
int ret = -ENODEV;
|
|
down_read(&bpf_devs_lock);
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offload = env->prog->aux->offload;
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if (offload)
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ret = offload->offdev->ops->insn_hook(env, insn_idx,
|
prev_insn_idx);
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up_read(&bpf_devs_lock);
|
|
return ret;
|
}
|
|
int bpf_prog_offload_finalize(struct bpf_verifier_env *env)
|
{
|
struct bpf_prog_offload *offload;
|
int ret = -ENODEV;
|
|
down_read(&bpf_devs_lock);
|
offload = env->prog->aux->offload;
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if (offload) {
|
if (offload->offdev->ops->finalize)
|
ret = offload->offdev->ops->finalize(env);
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else
|
ret = 0;
|
}
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up_read(&bpf_devs_lock);
|
|
return ret;
|
}
|
|
void
|
bpf_prog_offload_replace_insn(struct bpf_verifier_env *env, u32 off,
|
struct bpf_insn *insn)
|
{
|
const struct bpf_prog_offload_ops *ops;
|
struct bpf_prog_offload *offload;
|
int ret = -EOPNOTSUPP;
|
|
down_read(&bpf_devs_lock);
|
offload = env->prog->aux->offload;
|
if (offload) {
|
ops = offload->offdev->ops;
|
if (!offload->opt_failed && ops->replace_insn)
|
ret = ops->replace_insn(env, off, insn);
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offload->opt_failed |= ret;
|
}
|
up_read(&bpf_devs_lock);
|
}
|
|
void
|
bpf_prog_offload_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt)
|
{
|
struct bpf_prog_offload *offload;
|
int ret = -EOPNOTSUPP;
|
|
down_read(&bpf_devs_lock);
|
offload = env->prog->aux->offload;
|
if (offload) {
|
if (!offload->opt_failed && offload->offdev->ops->remove_insns)
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ret = offload->offdev->ops->remove_insns(env, off, cnt);
|
offload->opt_failed |= ret;
|
}
|
up_read(&bpf_devs_lock);
|
}
|
|
static void __bpf_prog_offload_destroy(struct bpf_prog *prog)
|
{
|
struct bpf_prog_offload *offload = prog->aux->offload;
|
|
if (offload->dev_state)
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offload->offdev->ops->destroy(prog);
|
|
/* Make sure BPF_PROG_GET_NEXT_ID can't find this dead program */
|
bpf_prog_free_id(prog, true);
|
|
list_del_init(&offload->offloads);
|
kfree(offload);
|
prog->aux->offload = NULL;
|
}
|
|
void bpf_prog_offload_destroy(struct bpf_prog *prog)
|
{
|
down_write(&bpf_devs_lock);
|
if (prog->aux->offload)
|
__bpf_prog_offload_destroy(prog);
|
up_write(&bpf_devs_lock);
|
}
|
|
static int bpf_prog_offload_translate(struct bpf_prog *prog)
|
{
|
struct bpf_prog_offload *offload;
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int ret = -ENODEV;
|
|
down_read(&bpf_devs_lock);
|
offload = prog->aux->offload;
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if (offload)
|
ret = offload->offdev->ops->translate(prog);
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up_read(&bpf_devs_lock);
|
|
return ret;
|
}
|
|
static unsigned int bpf_prog_warn_on_exec(const void *ctx,
|
const struct bpf_insn *insn)
|
{
|
WARN(1, "attempt to execute device eBPF program on the host!");
|
return 0;
|
}
|
|
int bpf_prog_offload_compile(struct bpf_prog *prog)
|
{
|
prog->bpf_func = bpf_prog_warn_on_exec;
|
|
return bpf_prog_offload_translate(prog);
|
}
|
|
struct ns_get_path_bpf_prog_args {
|
struct bpf_prog *prog;
|
struct bpf_prog_info *info;
|
};
|
|
static struct ns_common *bpf_prog_offload_info_fill_ns(void *private_data)
|
{
|
struct ns_get_path_bpf_prog_args *args = private_data;
|
struct bpf_prog_aux *aux = args->prog->aux;
|
struct ns_common *ns;
|
struct net *net;
|
|
rtnl_lock();
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down_read(&bpf_devs_lock);
|
|
if (aux->offload) {
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args->info->ifindex = aux->offload->netdev->ifindex;
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net = dev_net(aux->offload->netdev);
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get_net(net);
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ns = &net->ns;
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} else {
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args->info->ifindex = 0;
|
ns = NULL;
|
}
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|
up_read(&bpf_devs_lock);
|
rtnl_unlock();
|
|
return ns;
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}
|
|
int bpf_prog_offload_info_fill(struct bpf_prog_info *info,
|
struct bpf_prog *prog)
|
{
|
struct ns_get_path_bpf_prog_args args = {
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.prog = prog,
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.info = info,
|
};
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struct bpf_prog_aux *aux = prog->aux;
|
struct inode *ns_inode;
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struct path ns_path;
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char __user *uinsns;
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int res;
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u32 ulen;
|
|
res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args);
|
if (res) {
|
if (!info->ifindex)
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return -ENODEV;
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return res;
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}
|
|
down_read(&bpf_devs_lock);
|
|
if (!aux->offload) {
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up_read(&bpf_devs_lock);
|
return -ENODEV;
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}
|
|
ulen = info->jited_prog_len;
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info->jited_prog_len = aux->offload->jited_len;
|
if (info->jited_prog_len && ulen) {
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uinsns = u64_to_user_ptr(info->jited_prog_insns);
|
ulen = min_t(u32, info->jited_prog_len, ulen);
|
if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) {
|
up_read(&bpf_devs_lock);
|
return -EFAULT;
|
}
|
}
|
|
up_read(&bpf_devs_lock);
|
|
ns_inode = ns_path.dentry->d_inode;
|
info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev);
|
info->netns_ino = ns_inode->i_ino;
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path_put(&ns_path);
|
|
return 0;
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}
|
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const struct bpf_prog_ops bpf_offload_prog_ops = {
|
};
|
|
static int bpf_map_offload_ndo(struct bpf_offloaded_map *offmap,
|
enum bpf_netdev_command cmd)
|
{
|
struct netdev_bpf data = {};
|
struct net_device *netdev;
|
|
ASSERT_RTNL();
|
|
data.command = cmd;
|
data.offmap = offmap;
|
/* Caller must make sure netdev is valid */
|
netdev = offmap->netdev;
|
|
return netdev->netdev_ops->ndo_bpf(netdev, &data);
|
}
|
|
struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr)
|
{
|
struct net *net = current->nsproxy->net_ns;
|
struct bpf_offload_netdev *ondev;
|
struct bpf_offloaded_map *offmap;
|
int err;
|
|
if (!capable(CAP_SYS_ADMIN))
|
return ERR_PTR(-EPERM);
|
if (attr->map_type != BPF_MAP_TYPE_ARRAY &&
|
attr->map_type != BPF_MAP_TYPE_HASH)
|
return ERR_PTR(-EINVAL);
|
|
offmap = kzalloc(sizeof(*offmap), GFP_USER);
|
if (!offmap)
|
return ERR_PTR(-ENOMEM);
|
|
bpf_map_init_from_attr(&offmap->map, attr);
|
|
rtnl_lock();
|
down_write(&bpf_devs_lock);
|
offmap->netdev = __dev_get_by_index(net, attr->map_ifindex);
|
err = bpf_dev_offload_check(offmap->netdev);
|
if (err)
|
goto err_unlock;
|
|
ondev = bpf_offload_find_netdev(offmap->netdev);
|
if (!ondev) {
|
err = -EINVAL;
|
goto err_unlock;
|
}
|
|
err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC);
|
if (err)
|
goto err_unlock;
|
|
list_add_tail(&offmap->offloads, &ondev->maps);
|
up_write(&bpf_devs_lock);
|
rtnl_unlock();
|
|
return &offmap->map;
|
|
err_unlock:
|
up_write(&bpf_devs_lock);
|
rtnl_unlock();
|
kfree(offmap);
|
return ERR_PTR(err);
|
}
|
|
static void __bpf_map_offload_destroy(struct bpf_offloaded_map *offmap)
|
{
|
WARN_ON(bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_FREE));
|
/* Make sure BPF_MAP_GET_NEXT_ID can't find this dead map */
|
bpf_map_free_id(&offmap->map, true);
|
list_del_init(&offmap->offloads);
|
offmap->netdev = NULL;
|
}
|
|
void bpf_map_offload_map_free(struct bpf_map *map)
|
{
|
struct bpf_offloaded_map *offmap = map_to_offmap(map);
|
|
rtnl_lock();
|
down_write(&bpf_devs_lock);
|
if (offmap->netdev)
|
__bpf_map_offload_destroy(offmap);
|
up_write(&bpf_devs_lock);
|
rtnl_unlock();
|
|
kfree(offmap);
|
}
|
|
int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value)
|
{
|
struct bpf_offloaded_map *offmap = map_to_offmap(map);
|
int ret = -ENODEV;
|
|
down_read(&bpf_devs_lock);
|
if (offmap->netdev)
|
ret = offmap->dev_ops->map_lookup_elem(offmap, key, value);
|
up_read(&bpf_devs_lock);
|
|
return ret;
|
}
|
|
int bpf_map_offload_update_elem(struct bpf_map *map,
|
void *key, void *value, u64 flags)
|
{
|
struct bpf_offloaded_map *offmap = map_to_offmap(map);
|
int ret = -ENODEV;
|
|
if (unlikely(flags > BPF_EXIST))
|
return -EINVAL;
|
|
down_read(&bpf_devs_lock);
|
if (offmap->netdev)
|
ret = offmap->dev_ops->map_update_elem(offmap, key, value,
|
flags);
|
up_read(&bpf_devs_lock);
|
|
return ret;
|
}
|
|
int bpf_map_offload_delete_elem(struct bpf_map *map, void *key)
|
{
|
struct bpf_offloaded_map *offmap = map_to_offmap(map);
|
int ret = -ENODEV;
|
|
down_read(&bpf_devs_lock);
|
if (offmap->netdev)
|
ret = offmap->dev_ops->map_delete_elem(offmap, key);
|
up_read(&bpf_devs_lock);
|
|
return ret;
|
}
|
|
int bpf_map_offload_get_next_key(struct bpf_map *map, void *key, void *next_key)
|
{
|
struct bpf_offloaded_map *offmap = map_to_offmap(map);
|
int ret = -ENODEV;
|
|
down_read(&bpf_devs_lock);
|
if (offmap->netdev)
|
ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key);
|
up_read(&bpf_devs_lock);
|
|
return ret;
|
}
|
|
struct ns_get_path_bpf_map_args {
|
struct bpf_offloaded_map *offmap;
|
struct bpf_map_info *info;
|
};
|
|
static struct ns_common *bpf_map_offload_info_fill_ns(void *private_data)
|
{
|
struct ns_get_path_bpf_map_args *args = private_data;
|
struct ns_common *ns;
|
struct net *net;
|
|
rtnl_lock();
|
down_read(&bpf_devs_lock);
|
|
if (args->offmap->netdev) {
|
args->info->ifindex = args->offmap->netdev->ifindex;
|
net = dev_net(args->offmap->netdev);
|
get_net(net);
|
ns = &net->ns;
|
} else {
|
args->info->ifindex = 0;
|
ns = NULL;
|
}
|
|
up_read(&bpf_devs_lock);
|
rtnl_unlock();
|
|
return ns;
|
}
|
|
int bpf_map_offload_info_fill(struct bpf_map_info *info, struct bpf_map *map)
|
{
|
struct ns_get_path_bpf_map_args args = {
|
.offmap = map_to_offmap(map),
|
.info = info,
|
};
|
struct inode *ns_inode;
|
struct path ns_path;
|
int res;
|
|
res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args);
|
if (res) {
|
if (!info->ifindex)
|
return -ENODEV;
|
return res;
|
}
|
|
ns_inode = ns_path.dentry->d_inode;
|
info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev);
|
info->netns_ino = ns_inode->i_ino;
|
path_put(&ns_path);
|
|
return 0;
|
}
|
|
static bool __bpf_offload_dev_match(struct bpf_prog *prog,
|
struct net_device *netdev)
|
{
|
struct bpf_offload_netdev *ondev1, *ondev2;
|
struct bpf_prog_offload *offload;
|
|
if (!bpf_prog_is_dev_bound(prog->aux))
|
return false;
|
|
offload = prog->aux->offload;
|
if (!offload)
|
return false;
|
if (offload->netdev == netdev)
|
return true;
|
|
ondev1 = bpf_offload_find_netdev(offload->netdev);
|
ondev2 = bpf_offload_find_netdev(netdev);
|
|
return ondev1 && ondev2 && ondev1->offdev == ondev2->offdev;
|
}
|
|
bool bpf_offload_dev_match(struct bpf_prog *prog, struct net_device *netdev)
|
{
|
bool ret;
|
|
down_read(&bpf_devs_lock);
|
ret = __bpf_offload_dev_match(prog, netdev);
|
up_read(&bpf_devs_lock);
|
|
return ret;
|
}
|
EXPORT_SYMBOL_GPL(bpf_offload_dev_match);
|
|
bool bpf_offload_prog_map_match(struct bpf_prog *prog, struct bpf_map *map)
|
{
|
struct bpf_offloaded_map *offmap;
|
bool ret;
|
|
if (!bpf_map_is_dev_bound(map))
|
return bpf_map_offload_neutral(map);
|
offmap = map_to_offmap(map);
|
|
down_read(&bpf_devs_lock);
|
ret = __bpf_offload_dev_match(prog, offmap->netdev);
|
up_read(&bpf_devs_lock);
|
|
return ret;
|
}
|
|
int bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev,
|
struct net_device *netdev)
|
{
|
struct bpf_offload_netdev *ondev;
|
int err;
|
|
ondev = kzalloc(sizeof(*ondev), GFP_KERNEL);
|
if (!ondev)
|
return -ENOMEM;
|
|
ondev->netdev = netdev;
|
ondev->offdev = offdev;
|
INIT_LIST_HEAD(&ondev->progs);
|
INIT_LIST_HEAD(&ondev->maps);
|
|
down_write(&bpf_devs_lock);
|
err = rhashtable_insert_fast(&offdevs, &ondev->l, offdevs_params);
|
if (err) {
|
netdev_warn(netdev, "failed to register for BPF offload\n");
|
goto err_unlock_free;
|
}
|
|
list_add(&ondev->offdev_netdevs, &offdev->netdevs);
|
up_write(&bpf_devs_lock);
|
return 0;
|
|
err_unlock_free:
|
up_write(&bpf_devs_lock);
|
kfree(ondev);
|
return err;
|
}
|
EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_register);
|
|
void bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev,
|
struct net_device *netdev)
|
{
|
struct bpf_offload_netdev *ondev, *altdev;
|
struct bpf_offloaded_map *offmap, *mtmp;
|
struct bpf_prog_offload *offload, *ptmp;
|
|
ASSERT_RTNL();
|
|
down_write(&bpf_devs_lock);
|
ondev = rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params);
|
if (WARN_ON(!ondev))
|
goto unlock;
|
|
WARN_ON(rhashtable_remove_fast(&offdevs, &ondev->l, offdevs_params));
|
list_del(&ondev->offdev_netdevs);
|
|
/* Try to move the objects to another netdev of the device */
|
altdev = list_first_entry_or_null(&offdev->netdevs,
|
struct bpf_offload_netdev,
|
offdev_netdevs);
|
if (altdev) {
|
list_for_each_entry(offload, &ondev->progs, offloads)
|
offload->netdev = altdev->netdev;
|
list_splice_init(&ondev->progs, &altdev->progs);
|
|
list_for_each_entry(offmap, &ondev->maps, offloads)
|
offmap->netdev = altdev->netdev;
|
list_splice_init(&ondev->maps, &altdev->maps);
|
} else {
|
list_for_each_entry_safe(offload, ptmp, &ondev->progs, offloads)
|
__bpf_prog_offload_destroy(offload->prog);
|
list_for_each_entry_safe(offmap, mtmp, &ondev->maps, offloads)
|
__bpf_map_offload_destroy(offmap);
|
}
|
|
WARN_ON(!list_empty(&ondev->progs));
|
WARN_ON(!list_empty(&ondev->maps));
|
kfree(ondev);
|
unlock:
|
up_write(&bpf_devs_lock);
|
}
|
EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_unregister);
|
|
struct bpf_offload_dev *
|
bpf_offload_dev_create(const struct bpf_prog_offload_ops *ops, void *priv)
|
{
|
struct bpf_offload_dev *offdev;
|
int err;
|
|
down_write(&bpf_devs_lock);
|
if (!offdevs_inited) {
|
err = rhashtable_init(&offdevs, &offdevs_params);
|
if (err) {
|
up_write(&bpf_devs_lock);
|
return ERR_PTR(err);
|
}
|
offdevs_inited = true;
|
}
|
up_write(&bpf_devs_lock);
|
|
offdev = kzalloc(sizeof(*offdev), GFP_KERNEL);
|
if (!offdev)
|
return ERR_PTR(-ENOMEM);
|
|
offdev->ops = ops;
|
offdev->priv = priv;
|
INIT_LIST_HEAD(&offdev->netdevs);
|
|
return offdev;
|
}
|
EXPORT_SYMBOL_GPL(bpf_offload_dev_create);
|
|
void bpf_offload_dev_destroy(struct bpf_offload_dev *offdev)
|
{
|
WARN_ON(!list_empty(&offdev->netdevs));
|
kfree(offdev);
|
}
|
EXPORT_SYMBOL_GPL(bpf_offload_dev_destroy);
|
|
void *bpf_offload_dev_priv(struct bpf_offload_dev *offdev)
|
{
|
return offdev->priv;
|
}
|
EXPORT_SYMBOL_GPL(bpf_offload_dev_priv);
|
