kernel-ark/net/phonet/socket.c
David Howells cdfbabfb2f net: Work around lockdep limitation in sockets that use sockets
Lockdep issues a circular dependency warning when AFS issues an operation
through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.

The theory lockdep comes up with is as follows:

 (1) If the pagefault handler decides it needs to read pages from AFS, it
     calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
     creating a call requires the socket lock:

	mmap_sem must be taken before sk_lock-AF_RXRPC

 (2) afs_open_socket() opens an AF_RXRPC socket and binds it.  rxrpc_bind()
     binds the underlying UDP socket whilst holding its socket lock.
     inet_bind() takes its own socket lock:

	sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET

 (3) Reading from a TCP socket into a userspace buffer might cause a fault
     and thus cause the kernel to take the mmap_sem, but the TCP socket is
     locked whilst doing this:

	sk_lock-AF_INET must be taken before mmap_sem

However, lockdep's theory is wrong in this instance because it deals only
with lock classes and not individual locks.  The AF_INET lock in (2) isn't
really equivalent to the AF_INET lock in (3) as the former deals with a
socket entirely internal to the kernel that never sees userspace.  This is
a limitation in the design of lockdep.

Fix the general case by:

 (1) Double up all the locking keys used in sockets so that one set are
     used if the socket is created by userspace and the other set is used
     if the socket is created by the kernel.

 (2) Store the kern parameter passed to sk_alloc() in a variable in the
     sock struct (sk_kern_sock).  This informs sock_lock_init(),
     sock_init_data() and sk_clone_lock() as to the lock keys to be used.

     Note that the child created by sk_clone_lock() inherits the parent's
     kern setting.

 (3) Add a 'kern' parameter to ->accept() that is analogous to the one
     passed in to ->create() that distinguishes whether kernel_accept() or
     sys_accept4() was the caller and can be passed to sk_alloc().

     Note that a lot of accept functions merely dequeue an already
     allocated socket.  I haven't touched these as the new socket already
     exists before we get the parameter.

     Note also that there are a couple of places where I've made the accepted
     socket unconditionally kernel-based:

	irda_accept()
	rds_rcp_accept_one()
	tcp_accept_from_sock()

     because they follow a sock_create_kern() and accept off of that.

Whilst creating this, I noticed that lustre and ocfs don't create sockets
through sock_create_kern() and thus they aren't marked as for-kernel,
though they appear to be internal.  I wonder if these should do that so
that they use the new set of lock keys.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-09 18:23:27 -08:00

828 lines
18 KiB
C

/*
* File: socket.c
*
* Phonet sockets
*
* Copyright (C) 2008 Nokia Corporation.
*
* Authors: Sakari Ailus <sakari.ailus@nokia.com>
* Rémi Denis-Courmont
*
* 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.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include <linux/gfp.h>
#include <linux/kernel.h>
#include <linux/net.h>
#include <linux/poll.h>
#include <linux/sched/signal.h>
#include <net/sock.h>
#include <net/tcp_states.h>
#include <linux/phonet.h>
#include <linux/export.h>
#include <net/phonet/phonet.h>
#include <net/phonet/pep.h>
#include <net/phonet/pn_dev.h>
static int pn_socket_release(struct socket *sock)
{
struct sock *sk = sock->sk;
if (sk) {
sock->sk = NULL;
sk->sk_prot->close(sk, 0);
}
return 0;
}
#define PN_HASHSIZE 16
#define PN_HASHMASK (PN_HASHSIZE-1)
static struct {
struct hlist_head hlist[PN_HASHSIZE];
struct mutex lock;
} pnsocks;
void __init pn_sock_init(void)
{
unsigned int i;
for (i = 0; i < PN_HASHSIZE; i++)
INIT_HLIST_HEAD(pnsocks.hlist + i);
mutex_init(&pnsocks.lock);
}
static struct hlist_head *pn_hash_list(u16 obj)
{
return pnsocks.hlist + (obj & PN_HASHMASK);
}
/*
* Find address based on socket address, match only certain fields.
* Also grab sock if it was found. Remember to sock_put it later.
*/
struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *spn)
{
struct sock *sknode;
struct sock *rval = NULL;
u16 obj = pn_sockaddr_get_object(spn);
u8 res = spn->spn_resource;
struct hlist_head *hlist = pn_hash_list(obj);
rcu_read_lock();
sk_for_each_rcu(sknode, hlist) {
struct pn_sock *pn = pn_sk(sknode);
BUG_ON(!pn->sobject); /* unbound socket */
if (!net_eq(sock_net(sknode), net))
continue;
if (pn_port(obj)) {
/* Look up socket by port */
if (pn_port(pn->sobject) != pn_port(obj))
continue;
} else {
/* If port is zero, look up by resource */
if (pn->resource != res)
continue;
}
if (pn_addr(pn->sobject) &&
pn_addr(pn->sobject) != pn_addr(obj))
continue;
rval = sknode;
sock_hold(sknode);
break;
}
rcu_read_unlock();
return rval;
}
/* Deliver a broadcast packet (only in bottom-half) */
void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb)
{
struct hlist_head *hlist = pnsocks.hlist;
unsigned int h;
rcu_read_lock();
for (h = 0; h < PN_HASHSIZE; h++) {
struct sock *sknode;
sk_for_each(sknode, hlist) {
struct sk_buff *clone;
if (!net_eq(sock_net(sknode), net))
continue;
if (!sock_flag(sknode, SOCK_BROADCAST))
continue;
clone = skb_clone(skb, GFP_ATOMIC);
if (clone) {
sock_hold(sknode);
sk_receive_skb(sknode, clone, 0);
}
}
hlist++;
}
rcu_read_unlock();
}
int pn_sock_hash(struct sock *sk)
{
struct hlist_head *hlist = pn_hash_list(pn_sk(sk)->sobject);
mutex_lock(&pnsocks.lock);
sk_add_node_rcu(sk, hlist);
mutex_unlock(&pnsocks.lock);
return 0;
}
EXPORT_SYMBOL(pn_sock_hash);
void pn_sock_unhash(struct sock *sk)
{
mutex_lock(&pnsocks.lock);
sk_del_node_init_rcu(sk);
mutex_unlock(&pnsocks.lock);
pn_sock_unbind_all_res(sk);
synchronize_rcu();
}
EXPORT_SYMBOL(pn_sock_unhash);
static DEFINE_MUTEX(port_mutex);
static int pn_socket_bind(struct socket *sock, struct sockaddr *addr, int len)
{
struct sock *sk = sock->sk;
struct pn_sock *pn = pn_sk(sk);
struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
int err;
u16 handle;
u8 saddr;
if (sk->sk_prot->bind)
return sk->sk_prot->bind(sk, addr, len);
if (len < sizeof(struct sockaddr_pn))
return -EINVAL;
if (spn->spn_family != AF_PHONET)
return -EAFNOSUPPORT;
handle = pn_sockaddr_get_object((struct sockaddr_pn *)addr);
saddr = pn_addr(handle);
if (saddr && phonet_address_lookup(sock_net(sk), saddr))
return -EADDRNOTAVAIL;
lock_sock(sk);
if (sk->sk_state != TCP_CLOSE || pn_port(pn->sobject)) {
err = -EINVAL; /* attempt to rebind */
goto out;
}
WARN_ON(sk_hashed(sk));
mutex_lock(&port_mutex);
err = sk->sk_prot->get_port(sk, pn_port(handle));
if (err)
goto out_port;
/* get_port() sets the port, bind() sets the address if applicable */
pn->sobject = pn_object(saddr, pn_port(pn->sobject));
pn->resource = spn->spn_resource;
/* Enable RX on the socket */
err = sk->sk_prot->hash(sk);
out_port:
mutex_unlock(&port_mutex);
out:
release_sock(sk);
return err;
}
static int pn_socket_autobind(struct socket *sock)
{
struct sockaddr_pn sa;
int err;
memset(&sa, 0, sizeof(sa));
sa.spn_family = AF_PHONET;
err = pn_socket_bind(sock, (struct sockaddr *)&sa,
sizeof(struct sockaddr_pn));
if (err != -EINVAL)
return err;
BUG_ON(!pn_port(pn_sk(sock->sk)->sobject));
return 0; /* socket was already bound */
}
static int pn_socket_connect(struct socket *sock, struct sockaddr *addr,
int len, int flags)
{
struct sock *sk = sock->sk;
struct pn_sock *pn = pn_sk(sk);
struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
struct task_struct *tsk = current;
long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
int err;
if (pn_socket_autobind(sock))
return -ENOBUFS;
if (len < sizeof(struct sockaddr_pn))
return -EINVAL;
if (spn->spn_family != AF_PHONET)
return -EAFNOSUPPORT;
lock_sock(sk);
switch (sock->state) {
case SS_UNCONNECTED:
if (sk->sk_state != TCP_CLOSE) {
err = -EISCONN;
goto out;
}
break;
case SS_CONNECTING:
err = -EALREADY;
goto out;
default:
err = -EISCONN;
goto out;
}
pn->dobject = pn_sockaddr_get_object(spn);
pn->resource = pn_sockaddr_get_resource(spn);
sock->state = SS_CONNECTING;
err = sk->sk_prot->connect(sk, addr, len);
if (err) {
sock->state = SS_UNCONNECTED;
pn->dobject = 0;
goto out;
}
while (sk->sk_state == TCP_SYN_SENT) {
DEFINE_WAIT(wait);
if (!timeo) {
err = -EINPROGRESS;
goto out;
}
if (signal_pending(tsk)) {
err = sock_intr_errno(timeo);
goto out;
}
prepare_to_wait_exclusive(sk_sleep(sk), &wait,
TASK_INTERRUPTIBLE);
release_sock(sk);
timeo = schedule_timeout(timeo);
lock_sock(sk);
finish_wait(sk_sleep(sk), &wait);
}
if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED))
err = 0;
else if (sk->sk_state == TCP_CLOSE_WAIT)
err = -ECONNRESET;
else
err = -ECONNREFUSED;
sock->state = err ? SS_UNCONNECTED : SS_CONNECTED;
out:
release_sock(sk);
return err;
}
static int pn_socket_accept(struct socket *sock, struct socket *newsock,
int flags, bool kern)
{
struct sock *sk = sock->sk;
struct sock *newsk;
int err;
if (unlikely(sk->sk_state != TCP_LISTEN))
return -EINVAL;
newsk = sk->sk_prot->accept(sk, flags, &err, kern);
if (!newsk)
return err;
lock_sock(newsk);
sock_graft(newsk, newsock);
newsock->state = SS_CONNECTED;
release_sock(newsk);
return 0;
}
static int pn_socket_getname(struct socket *sock, struct sockaddr *addr,
int *sockaddr_len, int peer)
{
struct sock *sk = sock->sk;
struct pn_sock *pn = pn_sk(sk);
memset(addr, 0, sizeof(struct sockaddr_pn));
addr->sa_family = AF_PHONET;
if (!peer) /* Race with bind() here is userland's problem. */
pn_sockaddr_set_object((struct sockaddr_pn *)addr,
pn->sobject);
*sockaddr_len = sizeof(struct sockaddr_pn);
return 0;
}
static unsigned int pn_socket_poll(struct file *file, struct socket *sock,
poll_table *wait)
{
struct sock *sk = sock->sk;
struct pep_sock *pn = pep_sk(sk);
unsigned int mask = 0;
poll_wait(file, sk_sleep(sk), wait);
if (sk->sk_state == TCP_CLOSE)
return POLLERR;
if (!skb_queue_empty(&sk->sk_receive_queue))
mask |= POLLIN | POLLRDNORM;
if (!skb_queue_empty(&pn->ctrlreq_queue))
mask |= POLLPRI;
if (!mask && sk->sk_state == TCP_CLOSE_WAIT)
return POLLHUP;
if (sk->sk_state == TCP_ESTABLISHED &&
atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf &&
atomic_read(&pn->tx_credits))
mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
return mask;
}
static int pn_socket_ioctl(struct socket *sock, unsigned int cmd,
unsigned long arg)
{
struct sock *sk = sock->sk;
struct pn_sock *pn = pn_sk(sk);
if (cmd == SIOCPNGETOBJECT) {
struct net_device *dev;
u16 handle;
u8 saddr;
if (get_user(handle, (__u16 __user *)arg))
return -EFAULT;
lock_sock(sk);
if (sk->sk_bound_dev_if)
dev = dev_get_by_index(sock_net(sk),
sk->sk_bound_dev_if);
else
dev = phonet_device_get(sock_net(sk));
if (dev && (dev->flags & IFF_UP))
saddr = phonet_address_get(dev, pn_addr(handle));
else
saddr = PN_NO_ADDR;
release_sock(sk);
if (dev)
dev_put(dev);
if (saddr == PN_NO_ADDR)
return -EHOSTUNREACH;
handle = pn_object(saddr, pn_port(pn->sobject));
return put_user(handle, (__u16 __user *)arg);
}
return sk->sk_prot->ioctl(sk, cmd, arg);
}
static int pn_socket_listen(struct socket *sock, int backlog)
{
struct sock *sk = sock->sk;
int err = 0;
if (pn_socket_autobind(sock))
return -ENOBUFS;
lock_sock(sk);
if (sock->state != SS_UNCONNECTED) {
err = -EINVAL;
goto out;
}
if (sk->sk_state != TCP_LISTEN) {
sk->sk_state = TCP_LISTEN;
sk->sk_ack_backlog = 0;
}
sk->sk_max_ack_backlog = backlog;
out:
release_sock(sk);
return err;
}
static int pn_socket_sendmsg(struct socket *sock, struct msghdr *m,
size_t total_len)
{
struct sock *sk = sock->sk;
if (pn_socket_autobind(sock))
return -EAGAIN;
return sk->sk_prot->sendmsg(sk, m, total_len);
}
const struct proto_ops phonet_dgram_ops = {
.family = AF_PHONET,
.owner = THIS_MODULE,
.release = pn_socket_release,
.bind = pn_socket_bind,
.connect = sock_no_connect,
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.getname = pn_socket_getname,
.poll = datagram_poll,
.ioctl = pn_socket_ioctl,
.listen = sock_no_listen,
.shutdown = sock_no_shutdown,
.setsockopt = sock_no_setsockopt,
.getsockopt = sock_no_getsockopt,
#ifdef CONFIG_COMPAT
.compat_setsockopt = sock_no_setsockopt,
.compat_getsockopt = sock_no_getsockopt,
#endif
.sendmsg = pn_socket_sendmsg,
.recvmsg = sock_common_recvmsg,
.mmap = sock_no_mmap,
.sendpage = sock_no_sendpage,
};
const struct proto_ops phonet_stream_ops = {
.family = AF_PHONET,
.owner = THIS_MODULE,
.release = pn_socket_release,
.bind = pn_socket_bind,
.connect = pn_socket_connect,
.socketpair = sock_no_socketpair,
.accept = pn_socket_accept,
.getname = pn_socket_getname,
.poll = pn_socket_poll,
.ioctl = pn_socket_ioctl,
.listen = pn_socket_listen,
.shutdown = sock_no_shutdown,
.setsockopt = sock_common_setsockopt,
.getsockopt = sock_common_getsockopt,
#ifdef CONFIG_COMPAT
.compat_setsockopt = compat_sock_common_setsockopt,
.compat_getsockopt = compat_sock_common_getsockopt,
#endif
.sendmsg = pn_socket_sendmsg,
.recvmsg = sock_common_recvmsg,
.mmap = sock_no_mmap,
.sendpage = sock_no_sendpage,
};
EXPORT_SYMBOL(phonet_stream_ops);
/* allocate port for a socket */
int pn_sock_get_port(struct sock *sk, unsigned short sport)
{
static int port_cur;
struct net *net = sock_net(sk);
struct pn_sock *pn = pn_sk(sk);
struct sockaddr_pn try_sa;
struct sock *tmpsk;
memset(&try_sa, 0, sizeof(struct sockaddr_pn));
try_sa.spn_family = AF_PHONET;
WARN_ON(!mutex_is_locked(&port_mutex));
if (!sport) {
/* search free port */
int port, pmin, pmax;
phonet_get_local_port_range(&pmin, &pmax);
for (port = pmin; port <= pmax; port++) {
port_cur++;
if (port_cur < pmin || port_cur > pmax)
port_cur = pmin;
pn_sockaddr_set_port(&try_sa, port_cur);
tmpsk = pn_find_sock_by_sa(net, &try_sa);
if (tmpsk == NULL) {
sport = port_cur;
goto found;
} else
sock_put(tmpsk);
}
} else {
/* try to find specific port */
pn_sockaddr_set_port(&try_sa, sport);
tmpsk = pn_find_sock_by_sa(net, &try_sa);
if (tmpsk == NULL)
/* No sock there! We can use that port... */
goto found;
else
sock_put(tmpsk);
}
/* the port must be in use already */
return -EADDRINUSE;
found:
pn->sobject = pn_object(pn_addr(pn->sobject), sport);
return 0;
}
EXPORT_SYMBOL(pn_sock_get_port);
#ifdef CONFIG_PROC_FS
static struct sock *pn_sock_get_idx(struct seq_file *seq, loff_t pos)
{
struct net *net = seq_file_net(seq);
struct hlist_head *hlist = pnsocks.hlist;
struct sock *sknode;
unsigned int h;
for (h = 0; h < PN_HASHSIZE; h++) {
sk_for_each_rcu(sknode, hlist) {
if (!net_eq(net, sock_net(sknode)))
continue;
if (!pos)
return sknode;
pos--;
}
hlist++;
}
return NULL;
}
static struct sock *pn_sock_get_next(struct seq_file *seq, struct sock *sk)
{
struct net *net = seq_file_net(seq);
do
sk = sk_next(sk);
while (sk && !net_eq(net, sock_net(sk)));
return sk;
}
static void *pn_sock_seq_start(struct seq_file *seq, loff_t *pos)
__acquires(rcu)
{
rcu_read_lock();
return *pos ? pn_sock_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
}
static void *pn_sock_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct sock *sk;
if (v == SEQ_START_TOKEN)
sk = pn_sock_get_idx(seq, 0);
else
sk = pn_sock_get_next(seq, v);
(*pos)++;
return sk;
}
static void pn_sock_seq_stop(struct seq_file *seq, void *v)
__releases(rcu)
{
rcu_read_unlock();
}
static int pn_sock_seq_show(struct seq_file *seq, void *v)
{
seq_setwidth(seq, 127);
if (v == SEQ_START_TOKEN)
seq_puts(seq, "pt loc rem rs st tx_queue rx_queue "
" uid inode ref pointer drops");
else {
struct sock *sk = v;
struct pn_sock *pn = pn_sk(sk);
seq_printf(seq, "%2d %04X:%04X:%02X %02X %08X:%08X %5d %lu "
"%d %pK %d",
sk->sk_protocol, pn->sobject, pn->dobject,
pn->resource, sk->sk_state,
sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk),
from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
sock_i_ino(sk),
atomic_read(&sk->sk_refcnt), sk,
atomic_read(&sk->sk_drops));
}
seq_pad(seq, '\n');
return 0;
}
static const struct seq_operations pn_sock_seq_ops = {
.start = pn_sock_seq_start,
.next = pn_sock_seq_next,
.stop = pn_sock_seq_stop,
.show = pn_sock_seq_show,
};
static int pn_sock_open(struct inode *inode, struct file *file)
{
return seq_open_net(inode, file, &pn_sock_seq_ops,
sizeof(struct seq_net_private));
}
const struct file_operations pn_sock_seq_fops = {
.owner = THIS_MODULE,
.open = pn_sock_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_net,
};
#endif
static struct {
struct sock *sk[256];
} pnres;
/*
* Find and hold socket based on resource.
*/
struct sock *pn_find_sock_by_res(struct net *net, u8 res)
{
struct sock *sk;
if (!net_eq(net, &init_net))
return NULL;
rcu_read_lock();
sk = rcu_dereference(pnres.sk[res]);
if (sk)
sock_hold(sk);
rcu_read_unlock();
return sk;
}
static DEFINE_MUTEX(resource_mutex);
int pn_sock_bind_res(struct sock *sk, u8 res)
{
int ret = -EADDRINUSE;
if (!net_eq(sock_net(sk), &init_net))
return -ENOIOCTLCMD;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (pn_socket_autobind(sk->sk_socket))
return -EAGAIN;
mutex_lock(&resource_mutex);
if (pnres.sk[res] == NULL) {
sock_hold(sk);
rcu_assign_pointer(pnres.sk[res], sk);
ret = 0;
}
mutex_unlock(&resource_mutex);
return ret;
}
int pn_sock_unbind_res(struct sock *sk, u8 res)
{
int ret = -ENOENT;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
mutex_lock(&resource_mutex);
if (pnres.sk[res] == sk) {
RCU_INIT_POINTER(pnres.sk[res], NULL);
ret = 0;
}
mutex_unlock(&resource_mutex);
if (ret == 0) {
synchronize_rcu();
sock_put(sk);
}
return ret;
}
void pn_sock_unbind_all_res(struct sock *sk)
{
unsigned int res, match = 0;
mutex_lock(&resource_mutex);
for (res = 0; res < 256; res++) {
if (pnres.sk[res] == sk) {
RCU_INIT_POINTER(pnres.sk[res], NULL);
match++;
}
}
mutex_unlock(&resource_mutex);
while (match > 0) {
__sock_put(sk);
match--;
}
/* Caller is responsible for RCU sync before final sock_put() */
}
#ifdef CONFIG_PROC_FS
static struct sock **pn_res_get_idx(struct seq_file *seq, loff_t pos)
{
struct net *net = seq_file_net(seq);
unsigned int i;
if (!net_eq(net, &init_net))
return NULL;
for (i = 0; i < 256; i++) {
if (pnres.sk[i] == NULL)
continue;
if (!pos)
return pnres.sk + i;
pos--;
}
return NULL;
}
static struct sock **pn_res_get_next(struct seq_file *seq, struct sock **sk)
{
struct net *net = seq_file_net(seq);
unsigned int i;
BUG_ON(!net_eq(net, &init_net));
for (i = (sk - pnres.sk) + 1; i < 256; i++)
if (pnres.sk[i])
return pnres.sk + i;
return NULL;
}
static void *pn_res_seq_start(struct seq_file *seq, loff_t *pos)
__acquires(resource_mutex)
{
mutex_lock(&resource_mutex);
return *pos ? pn_res_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
}
static void *pn_res_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct sock **sk;
if (v == SEQ_START_TOKEN)
sk = pn_res_get_idx(seq, 0);
else
sk = pn_res_get_next(seq, v);
(*pos)++;
return sk;
}
static void pn_res_seq_stop(struct seq_file *seq, void *v)
__releases(resource_mutex)
{
mutex_unlock(&resource_mutex);
}
static int pn_res_seq_show(struct seq_file *seq, void *v)
{
seq_setwidth(seq, 63);
if (v == SEQ_START_TOKEN)
seq_puts(seq, "rs uid inode");
else {
struct sock **psk = v;
struct sock *sk = *psk;
seq_printf(seq, "%02X %5u %lu",
(int) (psk - pnres.sk),
from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
sock_i_ino(sk));
}
seq_pad(seq, '\n');
return 0;
}
static const struct seq_operations pn_res_seq_ops = {
.start = pn_res_seq_start,
.next = pn_res_seq_next,
.stop = pn_res_seq_stop,
.show = pn_res_seq_show,
};
static int pn_res_open(struct inode *inode, struct file *file)
{
return seq_open_net(inode, file, &pn_res_seq_ops,
sizeof(struct seq_net_private));
}
const struct file_operations pn_res_seq_fops = {
.owner = THIS_MODULE,
.open = pn_res_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_net,
};
#endif