linux-next/net/tipc/name_table.h
Eric Dumazet 6c36b5c244 net: tipc: remove one synchronize_net() from tipc_nametbl_stop()
tipc_exit_net() is very slow and is abused by syzbot.

tipc_nametbl_stop() is called for each netns being dismantled.

Calling synchronize_net() right before freeing tn->nametbl
is a big hammer.

Replace this with kfree_rcu().

Note that RCU is not properly used here, otherwise
tn->nametbl should be cleared before the synchronize_net()
or kfree_rcu(), or even before the cleanup loop.

We might need to fix this at some point.

Also note tipc uses other synchronize_rcu() calls,
more work is needed to make tipc_exit_net() much faster.

List of remaining calls to synchronize_rcu()

  tipc_detach_loopback() (dev_remove_pack())
  tipc_bcast_stop()
  tipc_sk_rht_destroy()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241204210234.319484-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-06 17:41:28 -08:00

158 lines
6.5 KiB
C

/*
* net/tipc/name_table.h: Include file for TIPC name table code
*
* Copyright (c) 2000-2006, 2014-2018, Ericsson AB
* Copyright (c) 2004-2005, 2010-2011, Wind River Systems
* Copyright (c) 2020-2021, Red Hat Inc
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the names of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _TIPC_NAME_TABLE_H
#define _TIPC_NAME_TABLE_H
struct tipc_subscription;
struct tipc_plist;
struct tipc_nlist;
struct tipc_group;
struct tipc_uaddr;
/*
* TIPC name types reserved for internal TIPC use (both current and planned)
*/
#define TIPC_ZM_SRV 3 /* zone master service name type */
#define TIPC_PUBL_SCOPE_NUM (TIPC_NODE_SCOPE + 1)
#define TIPC_NAMETBL_SIZE 1024 /* must be a power of 2 */
#define TIPC_ANY_SCOPE 10 /* Both node and cluster scope will match */
/**
* struct publication - info about a published service address or range
* @sr: service range represented by this publication
* @sk: address of socket bound to this publication
* @scope: scope of publication, TIPC_NODE_SCOPE or TIPC_CLUSTER_SCOPE
* @key: publication key, unique across the cluster
* @id: publication id
* @binding_node: all publications from the same node which bound this one
* - Remote publications: in node->publ_list;
* Used by node/name distr to withdraw publications when node is lost
* - Local/node scope publications: in name_table->node_scope list
* - Local/cluster scope publications: in name_table->cluster_scope list
* @binding_sock: all publications from the same socket which bound this one
* Used by socket to withdraw publications when socket is unbound/released
* @local_publ: list of identical publications made from this node
* Used by closest_first and multicast receive lookup algorithms
* @all_publ: all publications identical to this one, whatever node and scope
* Used by round-robin lookup algorithm
* @list: to form a list of publications in temporal order
* @rcu: RCU callback head used for deferred freeing
*/
struct publication {
struct tipc_service_range sr;
struct tipc_socket_addr sk;
u16 scope;
u32 key;
u32 id;
struct list_head binding_node;
struct list_head binding_sock;
struct list_head local_publ;
struct list_head all_publ;
struct list_head list;
struct rcu_head rcu;
};
/**
* struct name_table - table containing all existing port name publications
* @rcu: RCU callback head used for deferred freeing
* @services: name sequence hash lists
* @node_scope: all local publications with node scope
* - used by name_distr during re-init of name table
* @cluster_scope: all local publications with cluster scope
* - used by name_distr to send bulk updates to new nodes
* - used by name_distr during re-init of name table
* @cluster_scope_lock: lock for accessing @cluster_scope
* @local_publ_count: number of publications issued by this node
* @rc_dests: destination node counter
* @snd_nxt: next sequence number to be used
*/
struct name_table {
struct rcu_head rcu;
struct hlist_head services[TIPC_NAMETBL_SIZE];
struct list_head node_scope;
struct list_head cluster_scope;
rwlock_t cluster_scope_lock;
u32 local_publ_count;
u32 rc_dests;
u32 snd_nxt;
};
int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb);
bool tipc_nametbl_lookup_anycast(struct net *net, struct tipc_uaddr *ua,
struct tipc_socket_addr *sk);
void tipc_nametbl_lookup_mcast_sockets(struct net *net, struct tipc_uaddr *ua,
struct list_head *dports);
void tipc_nametbl_lookup_mcast_nodes(struct net *net, struct tipc_uaddr *ua,
struct tipc_nlist *nodes);
bool tipc_nametbl_lookup_group(struct net *net, struct tipc_uaddr *ua,
struct list_head *dsts, int *dstcnt,
u32 exclude, bool mcast);
void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp,
struct tipc_uaddr *ua);
struct publication *tipc_nametbl_publish(struct net *net, struct tipc_uaddr *ua,
struct tipc_socket_addr *sk, u32 key);
void tipc_nametbl_withdraw(struct net *net, struct tipc_uaddr *ua,
struct tipc_socket_addr *sk, u32 key);
struct publication *tipc_nametbl_insert_publ(struct net *net,
struct tipc_uaddr *ua,
struct tipc_socket_addr *sk,
u32 key);
struct publication *tipc_nametbl_remove_publ(struct net *net,
struct tipc_uaddr *ua,
struct tipc_socket_addr *sk,
u32 key);
bool tipc_nametbl_subscribe(struct tipc_subscription *s);
void tipc_nametbl_unsubscribe(struct tipc_subscription *s);
int tipc_nametbl_init(struct net *net);
void tipc_nametbl_stop(struct net *net);
struct tipc_dest {
struct list_head list;
u32 port;
u32 node;
};
struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port);
bool tipc_dest_push(struct list_head *l, u32 node, u32 port);
bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port);
bool tipc_dest_del(struct list_head *l, u32 node, u32 port);
void tipc_dest_list_purge(struct list_head *l);
#endif