vserver 1.9.3

[linux-2.6.git] / fs / devpts / inode.c

diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index 1d49ef4..db40284 100644 (file)
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -18,10 +18,9 @@
 #include <linux/mount.h>
 #include <linux/tty.h>
 #include <linux/devpts_fs.h>
+#include <linux/vs_base.h>
 #include "xattr.h"
 
-#define DEVPTS_SUPER_MAGIC 0x1cd1
-
 static struct vfsmount *devpts_mnt;
 static struct dentry *devpts_root;
 
@@ -70,6 +69,68 @@ static int devpts_remount(struct super_block *sb, int *flags, char *data)
        return 0;
 }
 
+static int devpts_readdir(struct file * filp, void * dirent, filldir_t filldir)
+{
+       struct dentry *dentry = filp->f_dentry;
+       struct dentry *cursor = filp->private_data;
+       struct list_head *p, *q = &cursor->d_child;
+       ino_t ino;
+       int i = filp->f_pos;
+
+       switch (i) {
+               case 0:
+                       ino = dentry->d_inode->i_ino;
+                       if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
+                               break;
+                       filp->f_pos++;
+                       i++;
+                       /* fallthrough */
+               case 1:
+                       ino = parent_ino(dentry);
+                       if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
+                               break;
+                       filp->f_pos++;
+                       i++;
+                       /* fallthrough */
+               default:
+                       spin_lock(&dcache_lock);
+                       if (filp->f_pos == 2) {
+                               list_del(q);
+                               list_add(q, &dentry->d_subdirs);
+                       }
+                       for (p=q->next; p != &dentry->d_subdirs; p=p->next) {
+                               struct dentry *next;
+                               next = list_entry(p, struct dentry, d_child);
+                               if (d_unhashed(next) || !next->d_inode)
+                                       continue;
+                               if (!vx_check(next->d_inode->i_xid, VX_IDENT))
+                                       continue;
+
+                               spin_unlock(&dcache_lock);
+                               if (filldir(dirent, next->d_name.name,
+                                       next->d_name.len, filp->f_pos,
+                                       next->d_inode->i_ino, DT_CHR) < 0)
+                                       return 0;
+                               spin_lock(&dcache_lock);
+                               /* next is still alive */
+                               list_del(q);
+                               list_add(q, p);
+                               p = q;
+                               filp->f_pos++;
+                       }
+                       spin_unlock(&dcache_lock);
+       }
+       return 0;
+}
+
+static struct file_operations devpts_dir_operations = {
+       .open           = dcache_dir_open,
+       .release        = dcache_dir_close,
+       .llseek         = dcache_dir_lseek,
+       .read           = generic_read_dir,
+       .readdir        = devpts_readdir,
+};
+
 static struct super_operations devpts_sops = {
        .statfs         = simple_statfs,
        .remount_fs     = devpts_remount,
@@ -95,8 +156,9 @@ devpts_fill_super(struct super_block *s, void *data, int silent)
        inode->i_uid = inode->i_gid = 0;
        inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR;
        inode->i_op = &simple_dir_inode_operations;
-       inode->i_fop = &simple_dir_operations;
+       inode->i_fop = &devpts_dir_operations;
        inode->i_nlink = 2;
+       inode->i_xid = vx_current_xid();
 
        devpts_root = s->s_root = d_alloc_root(inode);
        if (s->s_root)
@@ -134,11 +196,21 @@ static struct dentry *get_node(int num)
        return lookup_one_len(s, root, sprintf(s, "%d", num));
 }
 
+static int devpts_permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+       int ret = -EACCES;
+
+       if (vx_check(inode->i_xid, VX_IDENT))
+               ret = vfs_permission(inode, mask);
+       return ret;
+}
+
 static struct inode_operations devpts_file_inode_operations = {
        .setxattr       = devpts_setxattr,
        .getxattr       = devpts_getxattr,
        .listxattr      = devpts_listxattr,
        .removexattr    = devpts_removexattr,
+       .permission     = devpts_permission,
 };
 
 int devpts_pty_new(struct tty_struct *tty)
@@ -162,6 +234,7 @@ int devpts_pty_new(struct tty_struct *tty)
        inode->i_gid = config.setgid ? config.gid : current->fsgid;
        inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
        init_special_inode(inode, S_IFCHR|config.mode, device);
+       inode->i_xid = vx_current_xid();
        inode->i_op = &devpts_file_inode_operations;
        inode->u.generic_ip = tty;
 
@@ -179,8 +252,12 @@ struct tty_struct *devpts_get_tty(int number)
        struct dentry *dentry = get_node(number);
        struct tty_struct *tty;
 
-       tty = (IS_ERR(dentry) || !dentry->d_inode) ? NULL :
-                       dentry->d_inode->u.generic_ip;
+       tty = NULL;
+       if (!IS_ERR(dentry)) {
+               if (dentry->d_inode)
+                       tty = dentry->d_inode->u.generic_ip;
+               dput(dentry);
+       }
 
        up(&devpts_root->d_inode->i_sem);