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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-10-02 12:17:24 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-10-02 12:17:24 -0700 |
| commit | 3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch) | |
| tree | b767d7f6e26bc64334d3f14f8422d187239dc45d /net/sched/act_sample.c | |
| download | linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.zip | |
Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe:
- Fix a task_work add use-after-free with SQPOLL.
The sqpoll thread could pop and complete the last request while
io_req_normal_work_add() was still looking at them after the mpscq
push.
Use the same approach as DEFER_TASKRUN to protect from that, holding
an RCU read lock across the add, and have exit wait for an RCU grace
period for SQPOLL rings as well.
- CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the
big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED
rings
- Mark the source filter table as COW when cloning bpf filters, so
registering another filter on the source doesn't modify the shared
table in place
- Initialize the task context before running the BPF loop
- Requeue zcrx multishot receives stopped by a local resource
- End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit)
* tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
io_uring: fix task_work add use-after-free with SQPOLL
io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full
io_uring/zcrx: requeue multishot receives stopped by a local resource
io_uring: initialize task context before running the BPF loop
io_uring: zero big_cqe for aux CQEs on CQE32 rings
io_uring: fix free entry check for 32b CQEs on CQE32 rings
io_uring: only post the dummy skip CQE on CQE_MIXED rings
io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'net/sched/act_sample.c')
| -rw-r--r-- | net/sched/act_sample.c | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c new file mode 100644 index 000000000..44319a159 --- /dev/null +++ b/net/sched/act_sample.c @@ -0,0 +1,376 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * net/sched/act_sample.c - Packet sampling tc action + * Copyright (c) 2017 Yotam Gigi <yotamg@mellanox.com> + */ + +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <linux/skbuff.h> +#include <linux/rtnetlink.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/gfp.h> +#include <net/net_namespace.h> +#include <net/netlink.h> +#include <net/pkt_sched.h> +#include <linux/tc_act/tc_sample.h> +#include <net/tc_act/tc_sample.h> +#include <net/psample.h> +#include <net/pkt_cls.h> +#include <net/tc_wrapper.h> + +#include <linux/if_arp.h> + +static struct tc_action_ops act_sample_ops; + +static const struct nla_policy sample_policy[TCA_SAMPLE_MAX + 1] = { + [TCA_SAMPLE_PARMS] = { .len = sizeof(struct tc_sample) }, + [TCA_SAMPLE_RATE] = { .type = NLA_U32 }, + [TCA_SAMPLE_TRUNC_SIZE] = { .type = NLA_U32 }, + [TCA_SAMPLE_PSAMPLE_GROUP] = { .type = NLA_U32 }, +}; + +static int tcf_sample_init(struct net *net, struct nlattr *nla, + struct nlattr *est, struct tc_action **a, + struct tcf_proto *tp, + u32 flags, struct netlink_ext_ack *extack) +{ + struct tc_action_net *tn = net_generic(net, act_sample_ops.net_id); + bool bind = flags & TCA_ACT_FLAGS_BIND; + struct nlattr *tb[TCA_SAMPLE_MAX + 1]; + struct psample_group *psample_group; + u32 psample_group_num, rate, index; + struct tcf_chain *goto_ch = NULL; + struct tc_sample *parm; + struct tcf_sample *s; + bool exists = false; + int ret, err; + + if (!nla) + return -EINVAL; + ret = nla_parse_nested_deprecated(tb, TCA_SAMPLE_MAX, nla, + sample_policy, NULL); + if (ret < 0) + return ret; + + if (!tb[TCA_SAMPLE_PARMS]) + return -EINVAL; + + parm = nla_data(tb[TCA_SAMPLE_PARMS]); + index = parm->index; + err = tcf_idr_check_alloc(tn, &index, a, bind); + if (err < 0) + return err; + exists = err; + if (exists && bind) + return ACT_P_BOUND; + + if (!exists) { + ret = tcf_idr_create(tn, index, est, a, + &act_sample_ops, bind, true, flags); + if (ret) { + tcf_idr_cleanup(tn, index); + return ret; + } + ret = ACT_P_CREATED; + } else if (!(flags & TCA_ACT_FLAGS_REPLACE)) { + tcf_idr_release(*a, bind); + return -EEXIST; + } + + if (!tb[TCA_SAMPLE_RATE] || !tb[TCA_SAMPLE_PSAMPLE_GROUP]) { + NL_SET_ERR_MSG(extack, "sample rate and group are required"); + err = -EINVAL; + goto release_idr; + } + + err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); + if (err < 0) + goto release_idr; + + rate = nla_get_u32(tb[TCA_SAMPLE_RATE]); + if (!rate) { + NL_SET_ERR_MSG(extack, "invalid sample rate"); + err = -EINVAL; + goto put_chain; + } + psample_group_num = nla_get_u32(tb[TCA_SAMPLE_PSAMPLE_GROUP]); + psample_group = psample_group_get(net, psample_group_num); + if (!psample_group) { + err = -ENOMEM; + goto put_chain; + } + + s = to_sample(*a); + + spin_lock_bh(&s->tcf_lock); + goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); + s->rate = rate; + s->psample_group_num = psample_group_num; + psample_group = rcu_replace_pointer(s->psample_group, psample_group, + lockdep_is_held(&s->tcf_lock)); + + if (tb[TCA_SAMPLE_TRUNC_SIZE]) { + s->truncate = true; + s->trunc_size = nla_get_u32(tb[TCA_SAMPLE_TRUNC_SIZE]); + } + spin_unlock_bh(&s->tcf_lock); + + if (psample_group) + psample_group_put(psample_group); + if (goto_ch) + tcf_chain_put_by_act(goto_ch); + + return ret; +put_chain: + if (goto_ch) + tcf_chain_put_by_act(goto_ch); +release_idr: + tcf_idr_release(*a, bind); + return err; +} + +static void tcf_sample_cleanup(struct tc_action *a) +{ + struct tcf_sample *s = to_sample(a); + struct psample_group *psample_group; + + /* last reference to action, no need to lock */ + psample_group = rcu_dereference_protected(s->psample_group, 1); + RCU_INIT_POINTER(s->psample_group, NULL); + if (psample_group) + psample_group_put(psample_group); +} + +static bool tcf_sample_dev_ok_push(struct net_device *dev) +{ + switch (dev->type) { + case ARPHRD_TUNNEL: + case ARPHRD_TUNNEL6: + case ARPHRD_SIT: + case ARPHRD_IPGRE: + case ARPHRD_IP6GRE: + case ARPHRD_VOID: + case ARPHRD_NONE: + return false; + default: + return true; + } +} + +TC_INDIRECT_SCOPE int tcf_sample_act(struct sk_buff *skb, + const struct tc_action *a, + struct tcf_result *res) +{ + struct tcf_sample *s = to_sample(a); + struct psample_group *psample_group; + u8 cookie_data[TC_COOKIE_MAX_SIZE]; + struct psample_metadata md = {}; + struct tc_cookie *user_cookie; + int retval; + + tcf_lastuse_update(&s->tcf_tm); + bstats_update(this_cpu_ptr(s->common.cpu_bstats), skb); + retval = READ_ONCE(s->tcf_action); + + psample_group = rcu_dereference_bh(s->psample_group); + + /* randomly sample packets according to rate */ + if (psample_group && (get_random_u32_below(s->rate) == 0)) { + if (!skb_at_tc_ingress(skb)) { + md.in_ifindex = skb->skb_iif; + md.out_ifindex = skb->dev->ifindex; + } else { + md.in_ifindex = skb->dev->ifindex; + } + + /* on ingress, the mac header gets popped, so push it back */ + if (skb_at_tc_ingress(skb) && tcf_sample_dev_ok_push(skb->dev)) + skb_push(skb, skb->mac_len); + + rcu_read_lock(); + user_cookie = rcu_dereference(a->user_cookie); + if (user_cookie) { + memcpy(cookie_data, user_cookie->data, + user_cookie->len); + md.user_cookie = cookie_data; + md.user_cookie_len = user_cookie->len; + } + rcu_read_unlock(); + + md.trunc_size = s->truncate ? s->trunc_size : skb->len; + psample_sample_packet(psample_group, skb, s->rate, &md); + + if (skb_at_tc_ingress(skb) && tcf_sample_dev_ok_push(skb->dev)) + skb_pull(skb, skb->mac_len); + } + + return retval; +} + +static void tcf_sample_stats_update(struct tc_action *a, u64 bytes, u64 packets, + u64 drops, u64 lastuse, bool hw) +{ + struct tcf_sample *s = to_sample(a); + struct tcf_t *tm = &s->tcf_tm; + + tcf_action_update_stats(a, bytes, packets, drops, hw); + tm->lastuse = max_t(u64, tm->lastuse, lastuse); +} + +static int tcf_sample_dump(struct sk_buff *skb, struct tc_action *a, + int bind, int ref) +{ + unsigned char *b = skb_tail_pointer(skb); + struct tcf_sample *s = to_sample(a); + struct tc_sample opt = { + .index = s->tcf_index, + .refcnt = refcount_read(&s->tcf_refcnt) - ref, + .bindcnt = atomic_read(&s->tcf_bindcnt) - bind, + }; + struct tcf_t t; + + spin_lock_bh(&s->tcf_lock); + opt.action = s->tcf_action; + if (nla_put(skb, TCA_SAMPLE_PARMS, sizeof(opt), &opt)) + goto nla_put_failure; + + tcf_tm_dump(&t, &s->tcf_tm); + if (nla_put_64bit(skb, TCA_SAMPLE_TM, sizeof(t), &t, TCA_SAMPLE_PAD)) + goto nla_put_failure; + + if (nla_put_u32(skb, TCA_SAMPLE_RATE, s->rate)) + goto nla_put_failure; + + if (s->truncate) + if (nla_put_u32(skb, TCA_SAMPLE_TRUNC_SIZE, s->trunc_size)) + goto nla_put_failure; + + if (nla_put_u32(skb, TCA_SAMPLE_PSAMPLE_GROUP, s->psample_group_num)) + goto nla_put_failure; + spin_unlock_bh(&s->tcf_lock); + + return skb->len; + +nla_put_failure: + spin_unlock_bh(&s->tcf_lock); + nlmsg_trim(skb, b); + return -1; +} + +static void tcf_psample_group_put(void *priv) +{ + struct psample_group *group = priv; + + psample_group_put(group); +} + +static struct psample_group * +tcf_sample_get_group(const struct tc_action *a, + tc_action_priv_destructor *destructor) +{ + struct tcf_sample *s = to_sample(a); + struct psample_group *group; + + group = rcu_dereference_protected(s->psample_group, + lockdep_is_held(&s->tcf_lock)); + if (group) { + psample_group_take(group); + *destructor = tcf_psample_group_put; + } + + return group; +} + +static void tcf_offload_sample_get_group(struct flow_action_entry *entry, + const struct tc_action *act) +{ + entry->sample.psample_group = + act->ops->get_psample_group(act, &entry->destructor); + entry->destructor_priv = entry->sample.psample_group; +} + +static int tcf_sample_offload_act_setup(struct tc_action *act, void *entry_data, + u32 *index_inc, bool bind, + struct netlink_ext_ack *extack) +{ + if (bind) { + struct flow_action_entry *entry = entry_data; + + entry->id = FLOW_ACTION_SAMPLE; + entry->sample.trunc_size = tcf_sample_trunc_size(act); + entry->sample.truncate = tcf_sample_truncate(act); + entry->sample.rate = tcf_sample_rate(act); + tcf_offload_sample_get_group(entry, act); + *index_inc = 1; + } else { + struct flow_offload_action *fl_action = entry_data; + + fl_action->id = FLOW_ACTION_SAMPLE; + } + + return 0; +} + +static size_t tcf_sample_get_fill_size(const struct tc_action *act) +{ + return nla_total_size(sizeof(struct tc_sample)) /* TCA_SAMPLE_PARMS */ + + nla_total_size(sizeof(u32)) /* TCA_SAMPLE_RATE */ + + nla_total_size(sizeof(u32)) /* TCA_SAMPLE_TRUNC_SIZE */ + + nla_total_size(sizeof(u32)); /* TCA_SAMPLE_PSAMPLE_GROUP */ +} + +static struct tc_action_ops act_sample_ops = { + .kind = "sample", + .id = TCA_ID_SAMPLE, + .owner = THIS_MODULE, + .act = tcf_sample_act, + .stats_update = tcf_sample_stats_update, + .dump = tcf_sample_dump, + .init = tcf_sample_init, + .cleanup = tcf_sample_cleanup, + .get_fill_size = tcf_sample_get_fill_size, + .get_psample_group = tcf_sample_get_group, + .offload_act_setup = tcf_sample_offload_act_setup, + .size = sizeof(struct tcf_sample), +}; +MODULE_ALIAS_NET_ACT("sample"); + +static __net_init int sample_init_net(struct net *net) +{ + struct tc_action_net *tn = net_generic(net, act_sample_ops.net_id); + + return tc_action_net_init(net, tn, &act_sample_ops); +} + +static void __net_exit sample_exit_net(struct list_head *net_list) +{ + tc_action_net_exit(net_list, act_sample_ops.net_id); +} + +static struct pernet_operations sample_net_ops = { + .init = sample_init_net, + .exit_batch = sample_exit_net, + .id = &act_sample_ops.net_id, + .size = sizeof(struct tc_action_net), +}; + +static int __init sample_init_module(void) +{ + return tcf_register_action(&act_sample_ops, &sample_net_ops); +} + +static void __exit sample_cleanup_module(void) +{ + tcf_unregister_action(&act_sample_ops, &sample_net_ops); +} + +module_init(sample_init_module); +module_exit(sample_cleanup_module); + +MODULE_AUTHOR("Yotam Gigi <yotam.gi@gmail.com>"); +MODULE_DESCRIPTION("Packet sampling action"); +MODULE_LICENSE("GPL v2"); |
