linux/include/net/llc_conn.h
Cong Wang b905ef9ab9 llc: delete timers synchronously in llc_sk_free()
The connection timers of an llc sock could be still flying
after we delete them in llc_sk_free(), and even possibly
after we free the sock. We could just wait synchronously
here in case of troubles.

Note, I leave other call paths as they are, since they may
not have to wait, at least we can change them to synchronously
when needed.

Also, move the code to net/llc/llc_conn.c, which is apparently
a better place.

Reported-by: <syzbot+f922284c18ea23a8e457@syzkaller.appspotmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-22 14:55:03 -04:00

120 lines
4.1 KiB
C

#ifndef LLC_CONN_H
#define LLC_CONN_H
/*
* Copyright (c) 1997 by Procom Technology, Inc.
* 2001, 2002 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
*
* This program can be redistributed or modified under the terms of the
* GNU General Public License as published by the Free Software Foundation.
* This program is distributed without any warranty or implied warranty
* of merchantability or fitness for a particular purpose.
*
* See the GNU General Public License for more details.
*/
#include <linux/timer.h>
#include <net/llc_if.h>
#include <net/sock.h>
#include <linux/llc.h>
#define LLC_EVENT 1
#define LLC_PACKET 2
#define LLC2_P_TIME 2
#define LLC2_ACK_TIME 1
#define LLC2_REJ_TIME 3
#define LLC2_BUSY_TIME 3
struct llc_timer {
struct timer_list timer;
unsigned long expire; /* timer expire time */
};
struct llc_sock {
/* struct sock must be the first member of llc_sock */
struct sock sk;
struct sockaddr_llc addr; /* address sock is bound to */
u8 state; /* state of connection */
struct llc_sap *sap; /* pointer to parent SAP */
struct llc_addr laddr; /* lsap/mac pair */
struct llc_addr daddr; /* dsap/mac pair */
struct net_device *dev; /* device to send to remote */
u32 copied_seq; /* head of yet unread data */
u8 retry_count; /* number of retries */
u8 ack_must_be_send;
u8 first_pdu_Ns;
u8 npta;
struct llc_timer ack_timer;
struct llc_timer pf_cycle_timer;
struct llc_timer rej_sent_timer;
struct llc_timer busy_state_timer; /* ind busy clr at remote LLC */
u8 vS; /* seq# next in-seq I-PDU tx'd*/
u8 vR; /* seq# next in-seq I-PDU rx'd*/
u32 n2; /* max nbr re-tx's for timeout*/
u32 n1; /* max nbr octets in I PDU */
u8 k; /* tx window size; max = 127 */
u8 rw; /* rx window size; max = 127 */
u8 p_flag; /* state flags */
u8 f_flag;
u8 s_flag;
u8 data_flag;
u8 remote_busy_flag;
u8 cause_flag;
struct sk_buff_head pdu_unack_q; /* PUDs sent/waiting ack */
u16 link; /* network layer link number */
u8 X; /* a temporary variable */
u8 ack_pf; /* this flag indicates what is
the P-bit of acknowledge */
u8 failed_data_req; /* recognize that already exist a
failed llc_data_req_handler
(tx_buffer_full or unacceptable
state */
u8 dec_step;
u8 inc_cntr;
u8 dec_cntr;
u8 connect_step;
u8 last_nr; /* NR of last pdu received */
u32 rx_pdu_hdr; /* used for saving header of last pdu
received and caused sending FRMR.
Used for resending FRMR */
u32 cmsg_flags;
struct hlist_node dev_hash_node;
};
static inline struct llc_sock *llc_sk(const struct sock *sk)
{
return (struct llc_sock *)sk;
}
static __inline__ void llc_set_backlog_type(struct sk_buff *skb, char type)
{
skb->cb[sizeof(skb->cb) - 1] = type;
}
static __inline__ char llc_backlog_type(struct sk_buff *skb)
{
return skb->cb[sizeof(skb->cb) - 1];
}
struct sock *llc_sk_alloc(struct net *net, int family, gfp_t priority,
struct proto *prot, int kern);
void llc_sk_stop_all_timers(struct sock *sk, bool sync);
void llc_sk_free(struct sock *sk);
void llc_sk_reset(struct sock *sk);
/* Access to a connection */
int llc_conn_state_process(struct sock *sk, struct sk_buff *skb);
int llc_conn_send_pdu(struct sock *sk, struct sk_buff *skb);
void llc_conn_rtn_pdu(struct sock *sk, struct sk_buff *skb);
void llc_conn_resend_i_pdu_as_cmd(struct sock *sk, u8 nr, u8 first_p_bit);
void llc_conn_resend_i_pdu_as_rsp(struct sock *sk, u8 nr, u8 first_f_bit);
int llc_conn_remove_acked_pdus(struct sock *conn, u8 nr, u16 *how_many_unacked);
struct sock *llc_lookup_established(struct llc_sap *sap, struct llc_addr *daddr,
struct llc_addr *laddr);
void llc_sap_add_socket(struct llc_sap *sap, struct sock *sk);
void llc_sap_remove_socket(struct llc_sap *sap, struct sock *sk);
u8 llc_data_accept_state(u8 state);
void llc_build_offset_table(void);
#endif /* LLC_CONN_H */