linux_dsm_epyc7002/net/sctp/proc.c
NeilBrown c901381341 net: fix iteration for sctp transport seq_files
commit af8085f3a4712c57d0dd415ad543bac85780375c upstream.

The sctp transport seq_file iterators take a reference to the transport
in the ->start and ->next functions and releases the reference in the
->show function.  The preferred handling for such resources is to
release them in the subsequent ->next or ->stop function call.

Since Commit 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration
code and interface") there is no guarantee that ->show will be called
after ->next, so this function can now leak references.

So move the sctp_transport_put() call to ->next and ->stop.

Fixes: 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration code and interface")
Reported-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-17 11:02:29 +01:00

402 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* SCTP kernel implementation
* Copyright (c) 2003 International Business Machines, Corp.
*
* This file is part of the SCTP kernel implementation
*
* Please send any bug reports or fixes you make to the
* email address(es):
* lksctp developers <linux-sctp@vger.kernel.org>
*
* Written or modified by:
* Sridhar Samudrala <sri@us.ibm.com>
*/
#include <linux/types.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <linux/export.h>
#include <net/sctp/sctp.h>
#include <net/ip.h> /* for snmp_fold_field */
static const struct snmp_mib sctp_snmp_list[] = {
SNMP_MIB_ITEM("SctpCurrEstab", SCTP_MIB_CURRESTAB),
SNMP_MIB_ITEM("SctpActiveEstabs", SCTP_MIB_ACTIVEESTABS),
SNMP_MIB_ITEM("SctpPassiveEstabs", SCTP_MIB_PASSIVEESTABS),
SNMP_MIB_ITEM("SctpAborteds", SCTP_MIB_ABORTEDS),
SNMP_MIB_ITEM("SctpShutdowns", SCTP_MIB_SHUTDOWNS),
SNMP_MIB_ITEM("SctpOutOfBlues", SCTP_MIB_OUTOFBLUES),
SNMP_MIB_ITEM("SctpChecksumErrors", SCTP_MIB_CHECKSUMERRORS),
SNMP_MIB_ITEM("SctpOutCtrlChunks", SCTP_MIB_OUTCTRLCHUNKS),
SNMP_MIB_ITEM("SctpOutOrderChunks", SCTP_MIB_OUTORDERCHUNKS),
SNMP_MIB_ITEM("SctpOutUnorderChunks", SCTP_MIB_OUTUNORDERCHUNKS),
SNMP_MIB_ITEM("SctpInCtrlChunks", SCTP_MIB_INCTRLCHUNKS),
SNMP_MIB_ITEM("SctpInOrderChunks", SCTP_MIB_INORDERCHUNKS),
SNMP_MIB_ITEM("SctpInUnorderChunks", SCTP_MIB_INUNORDERCHUNKS),
SNMP_MIB_ITEM("SctpFragUsrMsgs", SCTP_MIB_FRAGUSRMSGS),
SNMP_MIB_ITEM("SctpReasmUsrMsgs", SCTP_MIB_REASMUSRMSGS),
SNMP_MIB_ITEM("SctpOutSCTPPacks", SCTP_MIB_OUTSCTPPACKS),
SNMP_MIB_ITEM("SctpInSCTPPacks", SCTP_MIB_INSCTPPACKS),
SNMP_MIB_ITEM("SctpT1InitExpireds", SCTP_MIB_T1_INIT_EXPIREDS),
SNMP_MIB_ITEM("SctpT1CookieExpireds", SCTP_MIB_T1_COOKIE_EXPIREDS),
SNMP_MIB_ITEM("SctpT2ShutdownExpireds", SCTP_MIB_T2_SHUTDOWN_EXPIREDS),
SNMP_MIB_ITEM("SctpT3RtxExpireds", SCTP_MIB_T3_RTX_EXPIREDS),
SNMP_MIB_ITEM("SctpT4RtoExpireds", SCTP_MIB_T4_RTO_EXPIREDS),
SNMP_MIB_ITEM("SctpT5ShutdownGuardExpireds", SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS),
SNMP_MIB_ITEM("SctpDelaySackExpireds", SCTP_MIB_DELAY_SACK_EXPIREDS),
SNMP_MIB_ITEM("SctpAutocloseExpireds", SCTP_MIB_AUTOCLOSE_EXPIREDS),
SNMP_MIB_ITEM("SctpT3Retransmits", SCTP_MIB_T3_RETRANSMITS),
SNMP_MIB_ITEM("SctpPmtudRetransmits", SCTP_MIB_PMTUD_RETRANSMITS),
SNMP_MIB_ITEM("SctpFastRetransmits", SCTP_MIB_FAST_RETRANSMITS),
SNMP_MIB_ITEM("SctpInPktSoftirq", SCTP_MIB_IN_PKT_SOFTIRQ),
SNMP_MIB_ITEM("SctpInPktBacklog", SCTP_MIB_IN_PKT_BACKLOG),
SNMP_MIB_ITEM("SctpInPktDiscards", SCTP_MIB_IN_PKT_DISCARDS),
SNMP_MIB_ITEM("SctpInDataChunkDiscards", SCTP_MIB_IN_DATA_CHUNK_DISCARDS),
SNMP_MIB_SENTINEL
};
/* Display sctp snmp mib statistics(/proc/net/sctp/snmp). */
static int sctp_snmp_seq_show(struct seq_file *seq, void *v)
{
unsigned long buff[SCTP_MIB_MAX];
struct net *net = seq->private;
int i;
memset(buff, 0, sizeof(unsigned long) * SCTP_MIB_MAX);
snmp_get_cpu_field_batch(buff, sctp_snmp_list,
net->sctp.sctp_statistics);
for (i = 0; sctp_snmp_list[i].name; i++)
seq_printf(seq, "%-32s\t%ld\n", sctp_snmp_list[i].name,
buff[i]);
return 0;
}
/* Dump local addresses of an association/endpoint. */
static void sctp_seq_dump_local_addrs(struct seq_file *seq, struct sctp_ep_common *epb)
{
struct sctp_association *asoc;
struct sctp_sockaddr_entry *laddr;
struct sctp_transport *peer;
union sctp_addr *addr, *primary = NULL;
struct sctp_af *af;
if (epb->type == SCTP_EP_TYPE_ASSOCIATION) {
asoc = sctp_assoc(epb);
peer = asoc->peer.primary_path;
if (unlikely(peer == NULL)) {
WARN(1, "Association %p with NULL primary path!\n", asoc);
return;
}
primary = &peer->saddr;
}
rcu_read_lock();
list_for_each_entry_rcu(laddr, &epb->bind_addr.address_list, list) {
if (!laddr->valid)
continue;
addr = &laddr->a;
af = sctp_get_af_specific(addr->sa.sa_family);
if (primary && af->cmp_addr(addr, primary)) {
seq_printf(seq, "*");
}
af->seq_dump_addr(seq, addr);
}
rcu_read_unlock();
}
/* Dump remote addresses of an association. */
static void sctp_seq_dump_remote_addrs(struct seq_file *seq, struct sctp_association *assoc)
{
struct sctp_transport *transport;
union sctp_addr *addr, *primary;
struct sctp_af *af;
primary = &assoc->peer.primary_addr;
list_for_each_entry_rcu(transport, &assoc->peer.transport_addr_list,
transports) {
addr = &transport->ipaddr;
af = sctp_get_af_specific(addr->sa.sa_family);
if (af->cmp_addr(addr, primary)) {
seq_printf(seq, "*");
}
af->seq_dump_addr(seq, addr);
}
}
static void *sctp_eps_seq_start(struct seq_file *seq, loff_t *pos)
{
if (*pos >= sctp_ep_hashsize)
return NULL;
if (*pos < 0)
*pos = 0;
if (*pos == 0)
seq_printf(seq, " ENDPT SOCK STY SST HBKT LPORT UID INODE LADDRS\n");
return (void *)pos;
}
static void sctp_eps_seq_stop(struct seq_file *seq, void *v)
{
}
static void *sctp_eps_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
if (++*pos >= sctp_ep_hashsize)
return NULL;
return pos;
}
/* Display sctp endpoints (/proc/net/sctp/eps). */
static int sctp_eps_seq_show(struct seq_file *seq, void *v)
{
struct sctp_hashbucket *head;
struct sctp_ep_common *epb;
struct sctp_endpoint *ep;
struct sock *sk;
int hash = *(loff_t *)v;
if (hash >= sctp_ep_hashsize)
return -ENOMEM;
head = &sctp_ep_hashtable[hash];
read_lock_bh(&head->lock);
sctp_for_each_hentry(epb, &head->chain) {
ep = sctp_ep(epb);
sk = epb->sk;
if (!net_eq(sock_net(sk), seq_file_net(seq)))
continue;
seq_printf(seq, "%8pK %8pK %-3d %-3d %-4d %-5d %5u %5lu ", ep, sk,
sctp_sk(sk)->type, sk->sk_state, hash,
epb->bind_addr.port,
from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
sock_i_ino(sk));
sctp_seq_dump_local_addrs(seq, epb);
seq_printf(seq, "\n");
}
read_unlock_bh(&head->lock);
return 0;
}
static const struct seq_operations sctp_eps_ops = {
.start = sctp_eps_seq_start,
.next = sctp_eps_seq_next,
.stop = sctp_eps_seq_stop,
.show = sctp_eps_seq_show,
};
struct sctp_ht_iter {
struct seq_net_private p;
struct rhashtable_iter hti;
};
static void *sctp_transport_seq_start(struct seq_file *seq, loff_t *pos)
{
struct sctp_ht_iter *iter = seq->private;
sctp_transport_walk_start(&iter->hti);
return sctp_transport_get_idx(seq_file_net(seq), &iter->hti, *pos);
}
static void sctp_transport_seq_stop(struct seq_file *seq, void *v)
{
struct sctp_ht_iter *iter = seq->private;
if (v && v != SEQ_START_TOKEN) {
struct sctp_transport *transport = v;
sctp_transport_put(transport);
}
sctp_transport_walk_stop(&iter->hti);
}
static void *sctp_transport_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct sctp_ht_iter *iter = seq->private;
if (v && v != SEQ_START_TOKEN) {
struct sctp_transport *transport = v;
sctp_transport_put(transport);
}
++*pos;
return sctp_transport_get_next(seq_file_net(seq), &iter->hti);
}
/* Display sctp associations (/proc/net/sctp/assocs). */
static int sctp_assocs_seq_show(struct seq_file *seq, void *v)
{
struct sctp_transport *transport;
struct sctp_association *assoc;
struct sctp_ep_common *epb;
struct sock *sk;
if (v == SEQ_START_TOKEN) {
seq_printf(seq, " ASSOC SOCK STY SST ST HBKT "
"ASSOC-ID TX_QUEUE RX_QUEUE UID INODE LPORT "
"RPORT LADDRS <-> RADDRS "
"HBINT INS OUTS MAXRT T1X T2X RTXC "
"wmema wmemq sndbuf rcvbuf\n");
return 0;
}
transport = (struct sctp_transport *)v;
assoc = transport->asoc;
epb = &assoc->base;
sk = epb->sk;
seq_printf(seq,
"%8pK %8pK %-3d %-3d %-2d %-4d "
"%4d %8d %8d %7u %5lu %-5d %5d ",
assoc, sk, sctp_sk(sk)->type, sk->sk_state,
assoc->state, 0,
assoc->assoc_id,
assoc->sndbuf_used,
atomic_read(&assoc->rmem_alloc),
from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
sock_i_ino(sk),
epb->bind_addr.port,
assoc->peer.port);
seq_printf(seq, " ");
sctp_seq_dump_local_addrs(seq, epb);
seq_printf(seq, "<-> ");
sctp_seq_dump_remote_addrs(seq, assoc);
seq_printf(seq, "\t%8lu %5d %5d %4d %4d %4d %8d "
"%8d %8d %8d %8d",
assoc->hbinterval, assoc->stream.incnt,
assoc->stream.outcnt, assoc->max_retrans,
assoc->init_retries, assoc->shutdown_retries,
assoc->rtx_data_chunks,
refcount_read(&sk->sk_wmem_alloc),
sk->sk_wmem_queued,
sk->sk_sndbuf,
sk->sk_rcvbuf);
seq_printf(seq, "\n");
return 0;
}
static const struct seq_operations sctp_assoc_ops = {
.start = sctp_transport_seq_start,
.next = sctp_transport_seq_next,
.stop = sctp_transport_seq_stop,
.show = sctp_assocs_seq_show,
};
static int sctp_remaddr_seq_show(struct seq_file *seq, void *v)
{
struct sctp_association *assoc;
struct sctp_transport *transport, *tsp;
if (v == SEQ_START_TOKEN) {
seq_printf(seq, "ADDR ASSOC_ID HB_ACT RTO MAX_PATH_RTX "
"REM_ADDR_RTX START STATE\n");
return 0;
}
transport = (struct sctp_transport *)v;
assoc = transport->asoc;
list_for_each_entry_rcu(tsp, &assoc->peer.transport_addr_list,
transports) {
/*
* The remote address (ADDR)
*/
tsp->af_specific->seq_dump_addr(seq, &tsp->ipaddr);
seq_printf(seq, " ");
/*
* The association ID (ASSOC_ID)
*/
seq_printf(seq, "%d ", tsp->asoc->assoc_id);
/*
* If the Heartbeat is active (HB_ACT)
* Note: 1 = Active, 0 = Inactive
*/
seq_printf(seq, "%d ", timer_pending(&tsp->hb_timer));
/*
* Retransmit time out (RTO)
*/
seq_printf(seq, "%lu ", tsp->rto);
/*
* Maximum path retransmit count (PATH_MAX_RTX)
*/
seq_printf(seq, "%d ", tsp->pathmaxrxt);
/*
* remote address retransmit count (REM_ADDR_RTX)
* Note: We don't have a way to tally this at the moment
* so lets just leave it as zero for the moment
*/
seq_puts(seq, "0 ");
/*
* remote address start time (START). This is also not
* currently implemented, but we can record it with a
* jiffies marker in a subsequent patch
*/
seq_puts(seq, "0 ");
/*
* The current state of this destination. I.e.
* SCTP_ACTIVE, SCTP_INACTIVE, ...
*/
seq_printf(seq, "%d", tsp->state);
seq_printf(seq, "\n");
}
return 0;
}
static const struct seq_operations sctp_remaddr_ops = {
.start = sctp_transport_seq_start,
.next = sctp_transport_seq_next,
.stop = sctp_transport_seq_stop,
.show = sctp_remaddr_seq_show,
};
/* Set up the proc fs entry for the SCTP protocol. */
int __net_init sctp_proc_init(struct net *net)
{
net->sctp.proc_net_sctp = proc_net_mkdir(net, "sctp", net->proc_net);
if (!net->sctp.proc_net_sctp)
return -ENOMEM;
if (!proc_create_net_single("snmp", 0444, net->sctp.proc_net_sctp,
sctp_snmp_seq_show, NULL))
goto cleanup;
if (!proc_create_net("eps", 0444, net->sctp.proc_net_sctp,
&sctp_eps_ops, sizeof(struct seq_net_private)))
goto cleanup;
if (!proc_create_net("assocs", 0444, net->sctp.proc_net_sctp,
&sctp_assoc_ops, sizeof(struct sctp_ht_iter)))
goto cleanup;
if (!proc_create_net("remaddr", 0444, net->sctp.proc_net_sctp,
&sctp_remaddr_ops, sizeof(struct sctp_ht_iter)))
goto cleanup;
return 0;
cleanup:
remove_proc_subtree("sctp", net->proc_net);
net->sctp.proc_net_sctp = NULL;
return -ENOMEM;
}