mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-25 02:09:42 +00:00
![Eric Dumazet](/assets/img/avatar_default.png)
Timer handlers do not imply rcu_read_lock(), so my recent fix
triggered a LOCKDEP warning when SYNACK is retransmit.
Lets add rcu_read_lock()/rcu_read_unlock() pairs around ireq->ireq_opt
usages instead of guessing what is done by callers, since it is
not worth the pain.
Get rid of ireq_opt_deref() helper since it hides the logic
without real benefit, since it is now a standard rcu_dereference().
Fixes: 1ad98e9d1b
("tcp/dccp: fix lockdep issue when SYN is backlogged")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
364 lines
9.2 KiB
C
364 lines
9.2 KiB
C
/*
|
|
* INET An implementation of the TCP/IP protocol suite for the LINUX
|
|
* operating system. INET is implemented using the BSD Socket
|
|
* interface as the means of communication with the user level.
|
|
*
|
|
* Definitions for inet_sock
|
|
*
|
|
* Authors: Many, reorganised here by
|
|
* Arnaldo Carvalho de Melo <acme@mandriva.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
#ifndef _INET_SOCK_H
|
|
#define _INET_SOCK_H
|
|
|
|
#include <linux/bitops.h>
|
|
#include <linux/string.h>
|
|
#include <linux/types.h>
|
|
#include <linux/jhash.h>
|
|
#include <linux/netdevice.h>
|
|
|
|
#include <net/flow.h>
|
|
#include <net/sock.h>
|
|
#include <net/request_sock.h>
|
|
#include <net/netns/hash.h>
|
|
#include <net/tcp_states.h>
|
|
#include <net/l3mdev.h>
|
|
|
|
/** struct ip_options - IP Options
|
|
*
|
|
* @faddr - Saved first hop address
|
|
* @nexthop - Saved nexthop address in LSRR and SSRR
|
|
* @is_strictroute - Strict source route
|
|
* @srr_is_hit - Packet destination addr was our one
|
|
* @is_changed - IP checksum more not valid
|
|
* @rr_needaddr - Need to record addr of outgoing dev
|
|
* @ts_needtime - Need to record timestamp
|
|
* @ts_needaddr - Need to record addr of outgoing dev
|
|
*/
|
|
struct ip_options {
|
|
__be32 faddr;
|
|
__be32 nexthop;
|
|
unsigned char optlen;
|
|
unsigned char srr;
|
|
unsigned char rr;
|
|
unsigned char ts;
|
|
unsigned char is_strictroute:1,
|
|
srr_is_hit:1,
|
|
is_changed:1,
|
|
rr_needaddr:1,
|
|
ts_needtime:1,
|
|
ts_needaddr:1;
|
|
unsigned char router_alert;
|
|
unsigned char cipso;
|
|
unsigned char __pad2;
|
|
unsigned char __data[0];
|
|
};
|
|
|
|
struct ip_options_rcu {
|
|
struct rcu_head rcu;
|
|
struct ip_options opt;
|
|
};
|
|
|
|
struct ip_options_data {
|
|
struct ip_options_rcu opt;
|
|
char data[40];
|
|
};
|
|
|
|
struct inet_request_sock {
|
|
struct request_sock req;
|
|
#define ir_loc_addr req.__req_common.skc_rcv_saddr
|
|
#define ir_rmt_addr req.__req_common.skc_daddr
|
|
#define ir_num req.__req_common.skc_num
|
|
#define ir_rmt_port req.__req_common.skc_dport
|
|
#define ir_v6_rmt_addr req.__req_common.skc_v6_daddr
|
|
#define ir_v6_loc_addr req.__req_common.skc_v6_rcv_saddr
|
|
#define ir_iif req.__req_common.skc_bound_dev_if
|
|
#define ir_cookie req.__req_common.skc_cookie
|
|
#define ireq_net req.__req_common.skc_net
|
|
#define ireq_state req.__req_common.skc_state
|
|
#define ireq_family req.__req_common.skc_family
|
|
|
|
u16 snd_wscale : 4,
|
|
rcv_wscale : 4,
|
|
tstamp_ok : 1,
|
|
sack_ok : 1,
|
|
wscale_ok : 1,
|
|
ecn_ok : 1,
|
|
acked : 1,
|
|
no_srccheck: 1,
|
|
smc_ok : 1;
|
|
u32 ir_mark;
|
|
union {
|
|
struct ip_options_rcu __rcu *ireq_opt;
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
struct {
|
|
struct ipv6_txoptions *ipv6_opt;
|
|
struct sk_buff *pktopts;
|
|
};
|
|
#endif
|
|
};
|
|
};
|
|
|
|
static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
|
|
{
|
|
return (struct inet_request_sock *)sk;
|
|
}
|
|
|
|
static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
if (!sk->sk_mark && sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept)
|
|
return skb->mark;
|
|
|
|
return sk->sk_mark;
|
|
}
|
|
|
|
static inline int inet_request_bound_dev_if(const struct sock *sk,
|
|
struct sk_buff *skb)
|
|
{
|
|
#ifdef CONFIG_NET_L3_MASTER_DEV
|
|
struct net *net = sock_net(sk);
|
|
|
|
if (!sk->sk_bound_dev_if && net->ipv4.sysctl_tcp_l3mdev_accept)
|
|
return l3mdev_master_ifindex_by_index(net, skb->skb_iif);
|
|
#endif
|
|
|
|
return sk->sk_bound_dev_if;
|
|
}
|
|
|
|
struct inet_cork {
|
|
unsigned int flags;
|
|
__be32 addr;
|
|
struct ip_options *opt;
|
|
unsigned int fragsize;
|
|
int length; /* Total length of all frames */
|
|
struct dst_entry *dst;
|
|
u8 tx_flags;
|
|
__u8 ttl;
|
|
__s16 tos;
|
|
char priority;
|
|
__u16 gso_size;
|
|
u64 transmit_time;
|
|
};
|
|
|
|
struct inet_cork_full {
|
|
struct inet_cork base;
|
|
struct flowi fl;
|
|
};
|
|
|
|
struct ip_mc_socklist;
|
|
struct ipv6_pinfo;
|
|
struct rtable;
|
|
|
|
/** struct inet_sock - representation of INET sockets
|
|
*
|
|
* @sk - ancestor class
|
|
* @pinet6 - pointer to IPv6 control block
|
|
* @inet_daddr - Foreign IPv4 addr
|
|
* @inet_rcv_saddr - Bound local IPv4 addr
|
|
* @inet_dport - Destination port
|
|
* @inet_num - Local port
|
|
* @inet_saddr - Sending source
|
|
* @uc_ttl - Unicast TTL
|
|
* @inet_sport - Source port
|
|
* @inet_id - ID counter for DF pkts
|
|
* @tos - TOS
|
|
* @mc_ttl - Multicasting TTL
|
|
* @is_icsk - is this an inet_connection_sock?
|
|
* @uc_index - Unicast outgoing device index
|
|
* @mc_index - Multicast device index
|
|
* @mc_list - Group array
|
|
* @cork - info to build ip hdr on each ip frag while socket is corked
|
|
*/
|
|
struct inet_sock {
|
|
/* sk and pinet6 has to be the first two members of inet_sock */
|
|
struct sock sk;
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
struct ipv6_pinfo *pinet6;
|
|
#endif
|
|
/* Socket demultiplex comparisons on incoming packets. */
|
|
#define inet_daddr sk.__sk_common.skc_daddr
|
|
#define inet_rcv_saddr sk.__sk_common.skc_rcv_saddr
|
|
#define inet_dport sk.__sk_common.skc_dport
|
|
#define inet_num sk.__sk_common.skc_num
|
|
|
|
__be32 inet_saddr;
|
|
__s16 uc_ttl;
|
|
__u16 cmsg_flags;
|
|
__be16 inet_sport;
|
|
__u16 inet_id;
|
|
|
|
struct ip_options_rcu __rcu *inet_opt;
|
|
int rx_dst_ifindex;
|
|
__u8 tos;
|
|
__u8 min_ttl;
|
|
__u8 mc_ttl;
|
|
__u8 pmtudisc;
|
|
__u8 recverr:1,
|
|
is_icsk:1,
|
|
freebind:1,
|
|
hdrincl:1,
|
|
mc_loop:1,
|
|
transparent:1,
|
|
mc_all:1,
|
|
nodefrag:1;
|
|
__u8 bind_address_no_port:1,
|
|
defer_connect:1; /* Indicates that fastopen_connect is set
|
|
* and cookie exists so we defer connect
|
|
* until first data frame is written
|
|
*/
|
|
__u8 rcv_tos;
|
|
__u8 convert_csum;
|
|
int uc_index;
|
|
int mc_index;
|
|
__be32 mc_addr;
|
|
struct ip_mc_socklist __rcu *mc_list;
|
|
struct inet_cork_full cork;
|
|
};
|
|
|
|
#define IPCORK_OPT 1 /* ip-options has been held in ipcork.opt */
|
|
#define IPCORK_ALLFRAG 2 /* always fragment (for ipv6 for now) */
|
|
|
|
/* cmsg flags for inet */
|
|
#define IP_CMSG_PKTINFO BIT(0)
|
|
#define IP_CMSG_TTL BIT(1)
|
|
#define IP_CMSG_TOS BIT(2)
|
|
#define IP_CMSG_RECVOPTS BIT(3)
|
|
#define IP_CMSG_RETOPTS BIT(4)
|
|
#define IP_CMSG_PASSSEC BIT(5)
|
|
#define IP_CMSG_ORIGDSTADDR BIT(6)
|
|
#define IP_CMSG_CHECKSUM BIT(7)
|
|
#define IP_CMSG_RECVFRAGSIZE BIT(8)
|
|
|
|
/**
|
|
* sk_to_full_sk - Access to a full socket
|
|
* @sk: pointer to a socket
|
|
*
|
|
* SYNACK messages might be attached to request sockets.
|
|
* Some places want to reach the listener in this case.
|
|
*/
|
|
static inline struct sock *sk_to_full_sk(struct sock *sk)
|
|
{
|
|
#ifdef CONFIG_INET
|
|
if (sk && sk->sk_state == TCP_NEW_SYN_RECV)
|
|
sk = inet_reqsk(sk)->rsk_listener;
|
|
#endif
|
|
return sk;
|
|
}
|
|
|
|
/* sk_to_full_sk() variant with a const argument */
|
|
static inline const struct sock *sk_const_to_full_sk(const struct sock *sk)
|
|
{
|
|
#ifdef CONFIG_INET
|
|
if (sk && sk->sk_state == TCP_NEW_SYN_RECV)
|
|
sk = ((const struct request_sock *)sk)->rsk_listener;
|
|
#endif
|
|
return sk;
|
|
}
|
|
|
|
static inline struct sock *skb_to_full_sk(const struct sk_buff *skb)
|
|
{
|
|
return sk_to_full_sk(skb->sk);
|
|
}
|
|
|
|
static inline struct inet_sock *inet_sk(const struct sock *sk)
|
|
{
|
|
return (struct inet_sock *)sk;
|
|
}
|
|
|
|
static inline void __inet_sk_copy_descendant(struct sock *sk_to,
|
|
const struct sock *sk_from,
|
|
const int ancestor_size)
|
|
{
|
|
memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
|
|
sk_from->sk_prot->obj_size - ancestor_size);
|
|
}
|
|
#if !(IS_ENABLED(CONFIG_IPV6))
|
|
static inline void inet_sk_copy_descendant(struct sock *sk_to,
|
|
const struct sock *sk_from)
|
|
{
|
|
__inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
|
|
}
|
|
#endif
|
|
|
|
int inet_sk_rebuild_header(struct sock *sk);
|
|
|
|
/**
|
|
* inet_sk_state_load - read sk->sk_state for lockless contexts
|
|
* @sk: socket pointer
|
|
*
|
|
* Paired with inet_sk_state_store(). Used in places we don't hold socket lock:
|
|
* tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ...
|
|
*/
|
|
static inline int inet_sk_state_load(const struct sock *sk)
|
|
{
|
|
/* state change might impact lockless readers. */
|
|
return smp_load_acquire(&sk->sk_state);
|
|
}
|
|
|
|
/**
|
|
* inet_sk_state_store - update sk->sk_state
|
|
* @sk: socket pointer
|
|
* @newstate: new state
|
|
*
|
|
* Paired with inet_sk_state_load(). Should be used in contexts where
|
|
* state change might impact lockless readers.
|
|
*/
|
|
void inet_sk_state_store(struct sock *sk, int newstate);
|
|
|
|
void inet_sk_set_state(struct sock *sk, int state);
|
|
|
|
static inline unsigned int __inet_ehashfn(const __be32 laddr,
|
|
const __u16 lport,
|
|
const __be32 faddr,
|
|
const __be16 fport,
|
|
u32 initval)
|
|
{
|
|
return jhash_3words((__force __u32) laddr,
|
|
(__force __u32) faddr,
|
|
((__u32) lport) << 16 | (__force __u32)fport,
|
|
initval);
|
|
}
|
|
|
|
struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops,
|
|
struct sock *sk_listener,
|
|
bool attach_listener);
|
|
|
|
static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
|
|
{
|
|
__u8 flags = 0;
|
|
|
|
if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl)
|
|
flags |= FLOWI_FLAG_ANYSRC;
|
|
return flags;
|
|
}
|
|
|
|
static inline void inet_inc_convert_csum(struct sock *sk)
|
|
{
|
|
inet_sk(sk)->convert_csum++;
|
|
}
|
|
|
|
static inline void inet_dec_convert_csum(struct sock *sk)
|
|
{
|
|
if (inet_sk(sk)->convert_csum > 0)
|
|
inet_sk(sk)->convert_csum--;
|
|
}
|
|
|
|
static inline bool inet_get_convert_csum(struct sock *sk)
|
|
{
|
|
return !!inet_sk(sk)->convert_csum;
|
|
}
|
|
|
|
|
|
static inline bool inet_can_nonlocal_bind(struct net *net,
|
|
struct inet_sock *inet)
|
|
{
|
|
return net->ipv4.sysctl_ip_nonlocal_bind ||
|
|
inet->freebind || inet->transparent;
|
|
}
|
|
|
|
#endif /* _INET_SOCK_H */
|