linux-stable/net/appletalk/atalk_proc.c
Vincent Duvert d0f6ba2ef2 appletalk: Fix atalk_proc_init() return path
Add a missing return statement to atalk_proc_init so it doesn't return
-ENOMEM when successful.  This allows the appletalk module to load
properly.

Fixes: e2bcd8b0ce ("appletalk: use remove_proc_subtree to simplify procfs code")
Link: https://www.downtowndougbrown.com/2020/08/hacking-up-a-fix-for-the-broken-appletalk-kernel-module-in-linux-5-1-and-newer/
Reported-by: Christopher KOBAYASHI <chris@disavowed.jp>
Reported-by: Doug Brown <doug@downtowndougbrown.com>
Signed-off-by: Vincent Duvert <vincent.ldev@duvert.net>
[lukas: add missing tags]
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v5.1+
Cc: Yue Haibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-03 15:48:32 -07:00

242 lines
5.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* atalk_proc.c - proc support for Appletalk
*
* Copyright(c) Arnaldo Carvalho de Melo <acme@conectiva.com.br>
*/
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <linux/atalk.h>
#include <linux/export.h>
static __inline__ struct atalk_iface *atalk_get_interface_idx(loff_t pos)
{
struct atalk_iface *i;
for (i = atalk_interfaces; pos && i; i = i->next)
--pos;
return i;
}
static void *atalk_seq_interface_start(struct seq_file *seq, loff_t *pos)
__acquires(atalk_interfaces_lock)
{
loff_t l = *pos;
read_lock_bh(&atalk_interfaces_lock);
return l ? atalk_get_interface_idx(--l) : SEQ_START_TOKEN;
}
static void *atalk_seq_interface_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct atalk_iface *i;
++*pos;
if (v == SEQ_START_TOKEN) {
i = NULL;
if (atalk_interfaces)
i = atalk_interfaces;
goto out;
}
i = v;
i = i->next;
out:
return i;
}
static void atalk_seq_interface_stop(struct seq_file *seq, void *v)
__releases(atalk_interfaces_lock)
{
read_unlock_bh(&atalk_interfaces_lock);
}
static int atalk_seq_interface_show(struct seq_file *seq, void *v)
{
struct atalk_iface *iface;
if (v == SEQ_START_TOKEN) {
seq_puts(seq, "Interface Address Networks "
"Status\n");
goto out;
}
iface = v;
seq_printf(seq, "%-16s %04X:%02X %04X-%04X %d\n",
iface->dev->name, ntohs(iface->address.s_net),
iface->address.s_node, ntohs(iface->nets.nr_firstnet),
ntohs(iface->nets.nr_lastnet), iface->status);
out:
return 0;
}
static __inline__ struct atalk_route *atalk_get_route_idx(loff_t pos)
{
struct atalk_route *r;
for (r = atalk_routes; pos && r; r = r->next)
--pos;
return r;
}
static void *atalk_seq_route_start(struct seq_file *seq, loff_t *pos)
__acquires(atalk_routes_lock)
{
loff_t l = *pos;
read_lock_bh(&atalk_routes_lock);
return l ? atalk_get_route_idx(--l) : SEQ_START_TOKEN;
}
static void *atalk_seq_route_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct atalk_route *r;
++*pos;
if (v == SEQ_START_TOKEN) {
r = NULL;
if (atalk_routes)
r = atalk_routes;
goto out;
}
r = v;
r = r->next;
out:
return r;
}
static void atalk_seq_route_stop(struct seq_file *seq, void *v)
__releases(atalk_routes_lock)
{
read_unlock_bh(&atalk_routes_lock);
}
static int atalk_seq_route_show(struct seq_file *seq, void *v)
{
struct atalk_route *rt;
if (v == SEQ_START_TOKEN) {
seq_puts(seq, "Target Router Flags Dev\n");
goto out;
}
if (atrtr_default.dev) {
rt = &atrtr_default;
seq_printf(seq, "Default %04X:%02X %-4d %s\n",
ntohs(rt->gateway.s_net), rt->gateway.s_node,
rt->flags, rt->dev->name);
}
rt = v;
seq_printf(seq, "%04X:%02X %04X:%02X %-4d %s\n",
ntohs(rt->target.s_net), rt->target.s_node,
ntohs(rt->gateway.s_net), rt->gateway.s_node,
rt->flags, rt->dev->name);
out:
return 0;
}
static void *atalk_seq_socket_start(struct seq_file *seq, loff_t *pos)
__acquires(atalk_sockets_lock)
{
read_lock_bh(&atalk_sockets_lock);
return seq_hlist_start_head(&atalk_sockets, *pos);
}
static void *atalk_seq_socket_next(struct seq_file *seq, void *v, loff_t *pos)
{
return seq_hlist_next(v, &atalk_sockets, pos);
}
static void atalk_seq_socket_stop(struct seq_file *seq, void *v)
__releases(atalk_sockets_lock)
{
read_unlock_bh(&atalk_sockets_lock);
}
static int atalk_seq_socket_show(struct seq_file *seq, void *v)
{
struct sock *s;
struct atalk_sock *at;
if (v == SEQ_START_TOKEN) {
seq_printf(seq, "Type Local_addr Remote_addr Tx_queue "
"Rx_queue St UID\n");
goto out;
}
s = sk_entry(v);
at = at_sk(s);
seq_printf(seq, "%02X %04X:%02X:%02X %04X:%02X:%02X %08X:%08X "
"%02X %u\n",
s->sk_type, ntohs(at->src_net), at->src_node, at->src_port,
ntohs(at->dest_net), at->dest_node, at->dest_port,
sk_wmem_alloc_get(s),
sk_rmem_alloc_get(s),
s->sk_state,
from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)));
out:
return 0;
}
static const struct seq_operations atalk_seq_interface_ops = {
.start = atalk_seq_interface_start,
.next = atalk_seq_interface_next,
.stop = atalk_seq_interface_stop,
.show = atalk_seq_interface_show,
};
static const struct seq_operations atalk_seq_route_ops = {
.start = atalk_seq_route_start,
.next = atalk_seq_route_next,
.stop = atalk_seq_route_stop,
.show = atalk_seq_route_show,
};
static const struct seq_operations atalk_seq_socket_ops = {
.start = atalk_seq_socket_start,
.next = atalk_seq_socket_next,
.stop = atalk_seq_socket_stop,
.show = atalk_seq_socket_show,
};
int __init atalk_proc_init(void)
{
if (!proc_mkdir("atalk", init_net.proc_net))
return -ENOMEM;
if (!proc_create_seq("atalk/interface", 0444, init_net.proc_net,
&atalk_seq_interface_ops))
goto out;
if (!proc_create_seq("atalk/route", 0444, init_net.proc_net,
&atalk_seq_route_ops))
goto out;
if (!proc_create_seq("atalk/socket", 0444, init_net.proc_net,
&atalk_seq_socket_ops))
goto out;
if (!proc_create_seq_private("atalk/arp", 0444, init_net.proc_net,
&aarp_seq_ops,
sizeof(struct aarp_iter_state), NULL))
goto out;
return 0;
out:
remove_proc_subtree("atalk", init_net.proc_net);
return -ENOMEM;
}
void atalk_proc_exit(void)
{
remove_proc_subtree("atalk", init_net.proc_net);
}