Fixed MTP to work with TWRP

fs/proc/proc_net.c

@@ -0,0 +1,232 @@
+/*
+ *  linux/fs/proc/net.c
+ *
+ *  Copyright (C) 2007
+ *
+ *  Author: Eric Biederman <ebiederm@xmission.com>
+ *
+ *  proc net directory handling functions
+ */
+
+#include <asm/uaccess.h>
+
+#include <linux/errno.h>
+#include <linux/time.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/bitops.h>
+#include <linux/mount.h>
+#include <linux/nsproxy.h>
+#include <net/net_namespace.h>
+#include <linux/seq_file.h>
+
+#include "internal.h"
+
+static inline struct net *PDE_NET(struct proc_dir_entry *pde)
+{
+	return pde->parent->data;
+}
+
+static struct net *get_proc_net(const struct inode *inode)
+{
+	return maybe_get_net(PDE_NET(PDE(inode)));
+}
+
+int seq_open_net(struct inode *ino, struct file *f,
+		 const struct seq_operations *ops, int size)
+{
+	struct net *net;
+	struct seq_net_private *p;
+
+	BUG_ON(size < sizeof(*p));
+
+	net = get_proc_net(ino);
+	if (net == NULL)
+		return -ENXIO;
+
+	p = __seq_open_private(f, ops, size);
+	if (p == NULL) {
+		put_net(net);
+		return -ENOMEM;
+	}
+#ifdef CONFIG_NET_NS
+	p->net = net;
+#endif
+	return 0;
+}
+EXPORT_SYMBOL_GPL(seq_open_net);
+
+int single_open_net(struct inode *inode, struct file *file,
+		int (*show)(struct seq_file *, void *))
+{
+	int err;
+	struct net *net;
+
+	err = -ENXIO;
+	net = get_proc_net(inode);
+	if (net == NULL)
+		goto err_net;
+
+	err = single_open(file, show, net);
+	if (err < 0)
+		goto err_open;
+
+	return 0;
+
+err_open:
+	put_net(net);
+err_net:
+	return err;
+}
+EXPORT_SYMBOL_GPL(single_open_net);
+
+int seq_release_net(struct inode *ino, struct file *f)
+{
+	struct seq_file *seq;
+
+	seq = f->private_data;
+
+	put_net(seq_file_net(seq));
+	seq_release_private(ino, f);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(seq_release_net);
+
+int single_release_net(struct inode *ino, struct file *f)
+{
+	struct seq_file *seq = f->private_data;
+	put_net(seq->private);
+	return single_release(ino, f);
+}
+EXPORT_SYMBOL_GPL(single_release_net);
+
+static struct net *get_proc_task_net(struct inode *dir)
+{
+	struct task_struct *task;
+	struct nsproxy *ns;
+	struct net *net = NULL;
+
+	rcu_read_lock();
+	task = pid_task(proc_pid(dir), PIDTYPE_PID);
+	if (task != NULL) {
+		task_lock(task);
+		ns = task->nsproxy;
+		if (ns != NULL)
+			net = get_net(ns->net_ns);
+		task_unlock(task);
+	}
+	rcu_read_unlock();
+
+	return net;
+}
+
+static struct dentry *proc_tgid_net_lookup(struct inode *dir,
+		struct dentry *dentry, unsigned int flags)
+{
+	struct dentry *de;
+	struct net *net;
+
+	de = ERR_PTR(-ENOENT);
+	net = get_proc_task_net(dir);
+	if (net != NULL) {
+		de = proc_lookup_de(net->proc_net, dir, dentry);
+		put_net(net);
+	}
+	return de;
+}
+
+static int proc_tgid_net_getattr(struct vfsmount *mnt, struct dentry *dentry,
+		struct kstat *stat)
+{
+	struct inode *inode = dentry->d_inode;
+	struct net *net;
+
+	net = get_proc_task_net(inode);
+
+	generic_fillattr(inode, stat);
+
+	if (net != NULL) {
+		stat->nlink = net->proc_net->nlink;
+		put_net(net);
+	}
+
+	return 0;
+}
+
+const struct inode_operations proc_net_inode_operations = {
+	.lookup		= proc_tgid_net_lookup,
+	.getattr	= proc_tgid_net_getattr,
+};
+
+static int proc_tgid_net_readdir(struct file *file, struct dir_context *ctx)
+{
+	int ret;
+	struct net *net;
+
+	ret = -EINVAL;
+	net = get_proc_task_net(file_inode(file));
+	if (net != NULL) {
+		ret = proc_readdir_de(net->proc_net, file, ctx);
+		put_net(net);
+	}
+	return ret;
+}
+
+const struct file_operations proc_net_operations = {
+	.llseek		= generic_file_llseek,
+	.read		= generic_read_dir,
+	.iterate	= proc_tgid_net_readdir,
+};
+
+static __net_init int proc_net_ns_init(struct net *net)
+{
+	struct proc_dir_entry *netd, *net_statd;
+	int err;
+
+	err = -ENOMEM;
+	netd = kzalloc(sizeof(*netd) + 4, GFP_KERNEL);
+	if (!netd)
+		goto out;
+
+	netd->data = net;
+	netd->nlink = 2;
+	netd->namelen = 3;
+	netd->parent = &proc_root;
+	memcpy(netd->name, "net", 4);
+
+	err = -EEXIST;
+	net_statd = proc_net_mkdir(net, "stat", netd);
+	if (!net_statd)
+		goto free_net;
+
+	net->proc_net = netd;
+	net->proc_net_stat = net_statd;
+	return 0;
+
+free_net:
+	kfree(netd);
+out:
+	return err;
+}
+
+static __net_exit void proc_net_ns_exit(struct net *net)
+{
+	remove_proc_entry("stat", net->proc_net);
+	kfree(net->proc_net);
+}
+
+static struct pernet_operations __net_initdata proc_net_ns_ops = {
+	.init = proc_net_ns_init,
+	.exit = proc_net_ns_exit,
+};
+
+int __init proc_net_init(void)
+{
+	proc_symlink("net", NULL, "self/net");
+
+	return register_pernet_subsys(&proc_net_ns_ops);
+}