And thus when we try to use 'ss -danemi' on these sockets that have no ccid blocks (data collected using systemtap after I fixed the problem): dccp_diag_get_info sk=0xffff8801220a3100, dp->dccps_hc_rx_ccid=0x0000000000000000, dp->dccps_hc_tx_ccid=0x0000000000000000 We get an OOPS: mica.ghostprotocols.net login: BUG: unable to handle kernel NULL pointer dereferenc0 IP: [<ffffffffa0136082>] dccp_diag_get_info+0x82/0xc0 [dccp_diag] PGD 12106f067 PUD 122488067 PMD 0 Oops: 0000 [#1] PREEMPT Fix is trivial, and 'ss -d' is working again: [root@mica ~]# ss -danemi State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 0 *:5001 *:* ino:7288 sk:220a3100ffff8801 mem:(r0,w0,f0,t0) cwnd:0 ssthresh:0 [root@mica ~]# Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
		
			
				
	
	
		
			74 lines
		
	
	
	
		
			1.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			74 lines
		
	
	
	
		
			1.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 *  net/dccp/diag.c
 | 
						|
 *
 | 
						|
 *  An implementation of the DCCP protocol
 | 
						|
 *  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 version 2 as
 | 
						|
 *	published by the Free Software Foundation.
 | 
						|
 */
 | 
						|
 | 
						|
 | 
						|
#include <linux/module.h>
 | 
						|
#include <linux/inet_diag.h>
 | 
						|
 | 
						|
#include "ccid.h"
 | 
						|
#include "dccp.h"
 | 
						|
 | 
						|
static void dccp_get_info(struct sock *sk, struct tcp_info *info)
 | 
						|
{
 | 
						|
	struct dccp_sock *dp = dccp_sk(sk);
 | 
						|
	const struct inet_connection_sock *icsk = inet_csk(sk);
 | 
						|
 | 
						|
	memset(info, 0, sizeof(*info));
 | 
						|
 | 
						|
	info->tcpi_state	= sk->sk_state;
 | 
						|
	info->tcpi_retransmits	= icsk->icsk_retransmits;
 | 
						|
	info->tcpi_probes	= icsk->icsk_probes_out;
 | 
						|
	info->tcpi_backoff	= icsk->icsk_backoff;
 | 
						|
	info->tcpi_pmtu		= icsk->icsk_pmtu_cookie;
 | 
						|
 | 
						|
	if (dp->dccps_hc_rx_ackvec != NULL)
 | 
						|
		info->tcpi_options |= TCPI_OPT_SACK;
 | 
						|
 | 
						|
	if (dp->dccps_hc_rx_ccid != NULL)
 | 
						|
		ccid_hc_rx_get_info(dp->dccps_hc_rx_ccid, sk, info);
 | 
						|
 | 
						|
	if (dp->dccps_hc_tx_ccid != NULL)
 | 
						|
		ccid_hc_tx_get_info(dp->dccps_hc_tx_ccid, sk, info);
 | 
						|
}
 | 
						|
 | 
						|
static void dccp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
 | 
						|
			       void *_info)
 | 
						|
{
 | 
						|
	r->idiag_rqueue = r->idiag_wqueue = 0;
 | 
						|
 | 
						|
	if (_info != NULL)
 | 
						|
		dccp_get_info(sk, _info);
 | 
						|
}
 | 
						|
 | 
						|
static const struct inet_diag_handler dccp_diag_handler = {
 | 
						|
	.idiag_hashinfo	 = &dccp_hashinfo,
 | 
						|
	.idiag_get_info	 = dccp_diag_get_info,
 | 
						|
	.idiag_type	 = DCCPDIAG_GETSOCK,
 | 
						|
	.idiag_info_size = sizeof(struct tcp_info),
 | 
						|
};
 | 
						|
 | 
						|
static int __init dccp_diag_init(void)
 | 
						|
{
 | 
						|
	return inet_diag_register(&dccp_diag_handler);
 | 
						|
}
 | 
						|
 | 
						|
static void __exit dccp_diag_fini(void)
 | 
						|
{
 | 
						|
	inet_diag_unregister(&dccp_diag_handler);
 | 
						|
}
 | 
						|
 | 
						|
module_init(dccp_diag_init);
 | 
						|
module_exit(dccp_diag_fini);
 | 
						|
 | 
						|
MODULE_LICENSE("GPL");
 | 
						|
MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
 | 
						|
MODULE_DESCRIPTION("DCCP inet_diag handler");
 | 
						|
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_INET_DIAG, DCCPDIAG_GETSOCK);
 |