2007-09-12 06:18:18 -06:00
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/*
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* linux/fs/proc/net.c
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*
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* Copyright (C) 2007
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*
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* Author: Eric Biederman <ebiederm@xmission.com>
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*
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* proc net directory handling functions
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*/
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#include <asm/uaccess.h>
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#include <linux/errno.h>
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#include <linux/time.h>
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#include <linux/proc_fs.h>
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#include <linux/stat.h>
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/module.h>
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#include <linux/bitops.h>
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#include <linux/smp_lock.h>
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#include <linux/mount.h>
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#include <linux/nsproxy.h>
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#include <net/net_namespace.h>
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2007-11-19 23:31:54 -07:00
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#include <linux/seq_file.h>
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2007-09-12 06:18:18 -06:00
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#include "internal.h"
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2007-11-19 23:31:54 -07:00
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int seq_open_net(struct inode *ino, struct file *f,
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const struct seq_operations *ops, int size)
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{
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struct net *net;
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struct seq_net_private *p;
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BUG_ON(size < sizeof(*p));
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net = get_proc_net(ino);
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if (net == NULL)
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return -ENXIO;
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p = __seq_open_private(f, ops, size);
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if (p == NULL) {
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put_net(net);
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return -ENOMEM;
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}
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2008-03-25 11:36:06 -06:00
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#ifdef CONFIG_NET_NS
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2007-11-19 23:31:54 -07:00
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p->net = net;
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2008-03-25 11:36:06 -06:00
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#endif
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2007-11-19 23:31:54 -07:00
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return 0;
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}
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EXPORT_SYMBOL_GPL(seq_open_net);
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int seq_release_net(struct inode *ino, struct file *f)
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{
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struct seq_file *seq;
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seq = f->private_data;
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2008-03-25 11:36:06 -06:00
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put_net(seq_file_net(seq));
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2007-11-19 23:31:54 -07:00
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seq_release_private(ino, f);
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return 0;
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}
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EXPORT_SYMBOL_GPL(seq_release_net);
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[NET]: Make /proc/net a symlink on /proc/self/net (v3)
Current /proc/net is done with so called "shadows", but current
implementation is broken and has little chances to get fixed.
The problem is that dentries subtree of /proc/net directory has
fancy revalidation rules to make processes living in different
net namespaces see different entries in /proc/net subtree, but
currently, tasks see in the /proc/net subdir the contents of any
other namespace, depending on who opened the file first.
The proposed fix is to turn /proc/net into a symlink, which points
to /proc/self/net, which in turn shows what previously was in
/proc/net - the network-related info, from the net namespace the
appropriate task lives in.
# ls -l /proc/net
lrwxrwxrwx 1 root root 8 Mar 5 15:17 /proc/net -> self/net
In other words - this behaves like /proc/mounts, but unlike
"mounts", "net" is not a file, but a directory.
Changes from v2:
* Fixed discrepancy of /proc/net nlink count and selinux labeling
screwup pointed out by Stephen.
To get the correct nlink count the ->getattr callback for /proc/net
is overridden to read one from the net->proc_net entry.
To make selinux still work the net->proc_net entry is initialized
properly, i.e. with the "net" name and the proc_net parent.
Selinux fixes are
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Changes from v1:
* Fixed a task_struct leak in get_proc_task_net, pointed out by Paul.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-07 12:08:40 -07:00
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static struct net *get_proc_task_net(struct inode *dir)
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{
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struct task_struct *task;
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struct nsproxy *ns;
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struct net *net = NULL;
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rcu_read_lock();
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task = pid_task(proc_pid(dir), PIDTYPE_PID);
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if (task != NULL) {
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ns = task_nsproxy(task);
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if (ns != NULL)
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net = get_net(ns->net_ns);
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}
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rcu_read_unlock();
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return net;
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}
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static struct dentry *proc_tgid_net_lookup(struct inode *dir,
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struct dentry *dentry, struct nameidata *nd)
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{
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struct dentry *de;
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struct net *net;
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de = ERR_PTR(-ENOENT);
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net = get_proc_task_net(dir);
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if (net != NULL) {
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de = proc_lookup_de(net->proc_net, dir, dentry);
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put_net(net);
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}
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return de;
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}
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static int proc_tgid_net_getattr(struct vfsmount *mnt, struct dentry *dentry,
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struct kstat *stat)
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{
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struct inode *inode = dentry->d_inode;
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struct net *net;
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net = get_proc_task_net(inode);
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generic_fillattr(inode, stat);
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if (net != NULL) {
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stat->nlink = net->proc_net->nlink;
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put_net(net);
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}
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return 0;
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}
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const struct inode_operations proc_net_inode_operations = {
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.lookup = proc_tgid_net_lookup,
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.getattr = proc_tgid_net_getattr,
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};
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static int proc_tgid_net_readdir(struct file *filp, void *dirent,
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filldir_t filldir)
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{
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int ret;
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struct net *net;
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ret = -EINVAL;
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net = get_proc_task_net(filp->f_path.dentry->d_inode);
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if (net != NULL) {
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ret = proc_readdir_de(net->proc_net, filp, dirent, filldir);
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put_net(net);
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}
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return ret;
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}
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const struct file_operations proc_net_operations = {
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.read = generic_read_dir,
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.readdir = proc_tgid_net_readdir,
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};
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2007-11-19 23:31:54 -07:00
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2007-09-12 06:18:18 -06:00
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struct proc_dir_entry *proc_net_fops_create(struct net *net,
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const char *name, mode_t mode, const struct file_operations *fops)
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{
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proc: fix ->open'less usage due to ->proc_fops flip
Typical PDE creation code looks like:
pde = create_proc_entry("foo", 0, NULL);
if (pde)
pde->proc_fops = &foo_proc_fops;
Notice that PDE is first created, only then ->proc_fops is set up to
final value. This is a problem because right after creation
a) PDE is fully visible in /proc , and
b) ->proc_fops are proc_file_operations which do not have ->open callback. So, it's
possible to ->read without ->open (see one class of oopses below).
The fix is new API called proc_create() which makes sure ->proc_fops are
set up before gluing PDE to main tree. Typical new code looks like:
pde = proc_create("foo", 0, NULL, &foo_proc_fops);
if (!pde)
return -ENOMEM;
Fix most networking users for a start.
In the long run, create_proc_entry() for regular files will go.
BUG: unable to handle kernel NULL pointer dereference at virtual address 00000024
printing eip: c1188c1b *pdpt = 000000002929e001 *pde = 0000000000000000
Oops: 0002 [#1] PREEMPT SMP DEBUG_PAGEALLOC
last sysfs file: /sys/block/sda/sda1/dev
Modules linked in: foo af_packet ipv6 cpufreq_ondemand loop serio_raw psmouse k8temp hwmon sr_mod cdrom
Pid: 24679, comm: cat Not tainted (2.6.24-rc3-mm1 #2)
EIP: 0060:[<c1188c1b>] EFLAGS: 00210002 CPU: 0
EIP is at mutex_lock_nested+0x75/0x25d
EAX: 000006fe EBX: fffffffb ECX: 00001000 EDX: e9340570
ESI: 00000020 EDI: 00200246 EBP: e9340570 ESP: e8ea1ef8
DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
Process cat (pid: 24679, ti=E8EA1000 task=E9340570 task.ti=E8EA1000)
Stack: 00000000 c106f7ce e8ee05b4 00000000 00000001 458003d0 f6fb6f20 fffffffb
00000000 c106f7aa 00001000 c106f7ce 08ae9000 f6db53f0 00000020 00200246
00000000 00000002 00000000 00200246 00200246 e8ee05a0 fffffffb e8ee0550
Call Trace:
[<c106f7ce>] seq_read+0x24/0x28a
[<c106f7aa>] seq_read+0x0/0x28a
[<c106f7ce>] seq_read+0x24/0x28a
[<c106f7aa>] seq_read+0x0/0x28a
[<c10818b8>] proc_reg_read+0x60/0x73
[<c1081858>] proc_reg_read+0x0/0x73
[<c105a34f>] vfs_read+0x6c/0x8b
[<c105a6f3>] sys_read+0x3c/0x63
[<c10025f2>] sysenter_past_esp+0x5f/0xa5
[<c10697a7>] destroy_inode+0x24/0x33
=======================
INFO: lockdep is turned off.
Code: 75 21 68 e1 1a 19 c1 68 87 00 00 00 68 b8 e8 1f c1 68 25 73 1f c1 e8 84 06 e9 ff e8 52 b8 e7 ff 83 c4 10 9c 5f fa e8 28 89 ea ff <f0> fe 4e 04 79 0a f3 90 80 7e 04 00 7e f8 eb f0 39 76 34 74 33
EIP: [<c1188c1b>] mutex_lock_nested+0x75/0x25d SS:ESP 0068:e8ea1ef8
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 05:18:37 -07:00
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return proc_create(name, mode, net->proc_net, fops);
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2007-09-12 06:18:18 -06:00
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}
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2007-09-12 06:51:47 -06:00
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EXPORT_SYMBOL_GPL(proc_net_fops_create);
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2007-09-12 06:18:18 -06:00
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void proc_net_remove(struct net *net, const char *name)
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{
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remove_proc_entry(name, net->proc_net);
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}
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2007-09-12 06:51:47 -06:00
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EXPORT_SYMBOL_GPL(proc_net_remove);
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2007-09-12 06:18:18 -06:00
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2007-09-13 01:18:57 -06:00
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struct net *get_proc_net(const struct inode *inode)
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{
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return maybe_get_net(PDE_NET(PDE(inode)));
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}
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EXPORT_SYMBOL_GPL(get_proc_net);
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2008-01-10 04:51:41 -07:00
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struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name,
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struct proc_dir_entry *parent)
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{
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struct proc_dir_entry *pde;
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pde = proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent);
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if (pde != NULL)
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pde->data = net;
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return pde;
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}
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EXPORT_SYMBOL_GPL(proc_net_mkdir);
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2007-10-08 21:38:39 -06:00
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static __net_init int proc_net_ns_init(struct net *net)
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2007-09-12 06:18:18 -06:00
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{
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[NET]: Make /proc/net a symlink on /proc/self/net (v3)
Current /proc/net is done with so called "shadows", but current
implementation is broken and has little chances to get fixed.
The problem is that dentries subtree of /proc/net directory has
fancy revalidation rules to make processes living in different
net namespaces see different entries in /proc/net subtree, but
currently, tasks see in the /proc/net subdir the contents of any
other namespace, depending on who opened the file first.
The proposed fix is to turn /proc/net into a symlink, which points
to /proc/self/net, which in turn shows what previously was in
/proc/net - the network-related info, from the net namespace the
appropriate task lives in.
# ls -l /proc/net
lrwxrwxrwx 1 root root 8 Mar 5 15:17 /proc/net -> self/net
In other words - this behaves like /proc/mounts, but unlike
"mounts", "net" is not a file, but a directory.
Changes from v2:
* Fixed discrepancy of /proc/net nlink count and selinux labeling
screwup pointed out by Stephen.
To get the correct nlink count the ->getattr callback for /proc/net
is overridden to read one from the net->proc_net entry.
To make selinux still work the net->proc_net entry is initialized
properly, i.e. with the "net" name and the proc_net parent.
Selinux fixes are
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Changes from v1:
* Fixed a task_struct leak in get_proc_task_net, pointed out by Paul.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-07 12:08:40 -07:00
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struct proc_dir_entry *netd, *net_statd;
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2007-09-12 06:18:18 -06:00
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int err;
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err = -ENOMEM;
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[NET]: Make /proc/net a symlink on /proc/self/net (v3)
Current /proc/net is done with so called "shadows", but current
implementation is broken and has little chances to get fixed.
The problem is that dentries subtree of /proc/net directory has
fancy revalidation rules to make processes living in different
net namespaces see different entries in /proc/net subtree, but
currently, tasks see in the /proc/net subdir the contents of any
other namespace, depending on who opened the file first.
The proposed fix is to turn /proc/net into a symlink, which points
to /proc/self/net, which in turn shows what previously was in
/proc/net - the network-related info, from the net namespace the
appropriate task lives in.
# ls -l /proc/net
lrwxrwxrwx 1 root root 8 Mar 5 15:17 /proc/net -> self/net
In other words - this behaves like /proc/mounts, but unlike
"mounts", "net" is not a file, but a directory.
Changes from v2:
* Fixed discrepancy of /proc/net nlink count and selinux labeling
screwup pointed out by Stephen.
To get the correct nlink count the ->getattr callback for /proc/net
is overridden to read one from the net->proc_net entry.
To make selinux still work the net->proc_net entry is initialized
properly, i.e. with the "net" name and the proc_net parent.
Selinux fixes are
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Changes from v1:
* Fixed a task_struct leak in get_proc_task_net, pointed out by Paul.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-07 12:08:40 -07:00
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netd = kzalloc(sizeof(*netd), GFP_KERNEL);
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if (!netd)
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2007-09-12 06:18:18 -06:00
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goto out;
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|
|
[NET]: Make /proc/net a symlink on /proc/self/net (v3)
Current /proc/net is done with so called "shadows", but current
implementation is broken and has little chances to get fixed.
The problem is that dentries subtree of /proc/net directory has
fancy revalidation rules to make processes living in different
net namespaces see different entries in /proc/net subtree, but
currently, tasks see in the /proc/net subdir the contents of any
other namespace, depending on who opened the file first.
The proposed fix is to turn /proc/net into a symlink, which points
to /proc/self/net, which in turn shows what previously was in
/proc/net - the network-related info, from the net namespace the
appropriate task lives in.
# ls -l /proc/net
lrwxrwxrwx 1 root root 8 Mar 5 15:17 /proc/net -> self/net
In other words - this behaves like /proc/mounts, but unlike
"mounts", "net" is not a file, but a directory.
Changes from v2:
* Fixed discrepancy of /proc/net nlink count and selinux labeling
screwup pointed out by Stephen.
To get the correct nlink count the ->getattr callback for /proc/net
is overridden to read one from the net->proc_net entry.
To make selinux still work the net->proc_net entry is initialized
properly, i.e. with the "net" name and the proc_net parent.
Selinux fixes are
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Changes from v1:
* Fixed a task_struct leak in get_proc_task_net, pointed out by Paul.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-07 12:08:40 -07:00
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netd->data = net;
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netd->nlink = 2;
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netd->name = "net";
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netd->namelen = 3;
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netd->parent = &proc_root;
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2007-09-12 06:18:18 -06:00
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err = -EEXIST;
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2008-01-10 04:51:41 -07:00
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net_statd = proc_net_mkdir(net, "stat", netd);
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2007-09-12 06:18:18 -06:00
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if (!net_statd)
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goto free_net;
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net->proc_net = netd;
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net->proc_net_stat = net_statd;
|
[NET]: Make /proc/net a symlink on /proc/self/net (v3)
Current /proc/net is done with so called "shadows", but current
implementation is broken and has little chances to get fixed.
The problem is that dentries subtree of /proc/net directory has
fancy revalidation rules to make processes living in different
net namespaces see different entries in /proc/net subtree, but
currently, tasks see in the /proc/net subdir the contents of any
other namespace, depending on who opened the file first.
The proposed fix is to turn /proc/net into a symlink, which points
to /proc/self/net, which in turn shows what previously was in
/proc/net - the network-related info, from the net namespace the
appropriate task lives in.
# ls -l /proc/net
lrwxrwxrwx 1 root root 8 Mar 5 15:17 /proc/net -> self/net
In other words - this behaves like /proc/mounts, but unlike
"mounts", "net" is not a file, but a directory.
Changes from v2:
* Fixed discrepancy of /proc/net nlink count and selinux labeling
screwup pointed out by Stephen.
To get the correct nlink count the ->getattr callback for /proc/net
is overridden to read one from the net->proc_net entry.
To make selinux still work the net->proc_net entry is initialized
properly, i.e. with the "net" name and the proc_net parent.
Selinux fixes are
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Changes from v1:
* Fixed a task_struct leak in get_proc_task_net, pointed out by Paul.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-07 12:08:40 -07:00
|
|
|
return 0;
|
2007-09-12 06:18:18 -06:00
|
|
|
|
[NET]: Make /proc/net a symlink on /proc/self/net (v3)
Current /proc/net is done with so called "shadows", but current
implementation is broken and has little chances to get fixed.
The problem is that dentries subtree of /proc/net directory has
fancy revalidation rules to make processes living in different
net namespaces see different entries in /proc/net subtree, but
currently, tasks see in the /proc/net subdir the contents of any
other namespace, depending on who opened the file first.
The proposed fix is to turn /proc/net into a symlink, which points
to /proc/self/net, which in turn shows what previously was in
/proc/net - the network-related info, from the net namespace the
appropriate task lives in.
# ls -l /proc/net
lrwxrwxrwx 1 root root 8 Mar 5 15:17 /proc/net -> self/net
In other words - this behaves like /proc/mounts, but unlike
"mounts", "net" is not a file, but a directory.
Changes from v2:
* Fixed discrepancy of /proc/net nlink count and selinux labeling
screwup pointed out by Stephen.
To get the correct nlink count the ->getattr callback for /proc/net
is overridden to read one from the net->proc_net entry.
To make selinux still work the net->proc_net entry is initialized
properly, i.e. with the "net" name and the proc_net parent.
Selinux fixes are
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Changes from v1:
* Fixed a task_struct leak in get_proc_task_net, pointed out by Paul.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-07 12:08:40 -07:00
|
|
|
free_net:
|
|
|
|
kfree(netd);
|
2007-09-12 06:18:18 -06:00
|
|
|
out:
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
2007-10-08 21:38:39 -06:00
|
|
|
static __net_exit void proc_net_ns_exit(struct net *net)
|
2007-09-12 06:18:18 -06:00
|
|
|
{
|
|
|
|
remove_proc_entry("stat", net->proc_net);
|
[NET]: Make /proc/net a symlink on /proc/self/net (v3)
Current /proc/net is done with so called "shadows", but current
implementation is broken and has little chances to get fixed.
The problem is that dentries subtree of /proc/net directory has
fancy revalidation rules to make processes living in different
net namespaces see different entries in /proc/net subtree, but
currently, tasks see in the /proc/net subdir the contents of any
other namespace, depending on who opened the file first.
The proposed fix is to turn /proc/net into a symlink, which points
to /proc/self/net, which in turn shows what previously was in
/proc/net - the network-related info, from the net namespace the
appropriate task lives in.
# ls -l /proc/net
lrwxrwxrwx 1 root root 8 Mar 5 15:17 /proc/net -> self/net
In other words - this behaves like /proc/mounts, but unlike
"mounts", "net" is not a file, but a directory.
Changes from v2:
* Fixed discrepancy of /proc/net nlink count and selinux labeling
screwup pointed out by Stephen.
To get the correct nlink count the ->getattr callback for /proc/net
is overridden to read one from the net->proc_net entry.
To make selinux still work the net->proc_net entry is initialized
properly, i.e. with the "net" name and the proc_net parent.
Selinux fixes are
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Changes from v1:
* Fixed a task_struct leak in get_proc_task_net, pointed out by Paul.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-07 12:08:40 -07:00
|
|
|
kfree(net->proc_net);
|
2007-09-12 06:18:18 -06:00
|
|
|
}
|
|
|
|
|
2007-11-13 04:23:50 -07:00
|
|
|
static struct pernet_operations __net_initdata proc_net_ns_ops = {
|
2007-09-12 06:18:18 -06:00
|
|
|
.init = proc_net_ns_init,
|
|
|
|
.exit = proc_net_ns_exit,
|
|
|
|
};
|
|
|
|
|
2007-10-08 21:38:39 -06:00
|
|
|
int __init proc_net_init(void)
|
2007-09-12 06:18:18 -06:00
|
|
|
{
|
[NET]: Make /proc/net a symlink on /proc/self/net (v3)
Current /proc/net is done with so called "shadows", but current
implementation is broken and has little chances to get fixed.
The problem is that dentries subtree of /proc/net directory has
fancy revalidation rules to make processes living in different
net namespaces see different entries in /proc/net subtree, but
currently, tasks see in the /proc/net subdir the contents of any
other namespace, depending on who opened the file first.
The proposed fix is to turn /proc/net into a symlink, which points
to /proc/self/net, which in turn shows what previously was in
/proc/net - the network-related info, from the net namespace the
appropriate task lives in.
# ls -l /proc/net
lrwxrwxrwx 1 root root 8 Mar 5 15:17 /proc/net -> self/net
In other words - this behaves like /proc/mounts, but unlike
"mounts", "net" is not a file, but a directory.
Changes from v2:
* Fixed discrepancy of /proc/net nlink count and selinux labeling
screwup pointed out by Stephen.
To get the correct nlink count the ->getattr callback for /proc/net
is overridden to read one from the net->proc_net entry.
To make selinux still work the net->proc_net entry is initialized
properly, i.e. with the "net" name and the proc_net parent.
Selinux fixes are
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Changes from v1:
* Fixed a task_struct leak in get_proc_task_net, pointed out by Paul.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-07 12:08:40 -07:00
|
|
|
proc_symlink("net", NULL, "self/net");
|
2007-09-12 06:18:18 -06:00
|
|
|
|
|
|
|
return register_pernet_subsys(&proc_net_ns_ops);
|
|
|
|
}
|