[PATCH] Prevent memory leak in devpts

[Olaf Kirch]

Hi,

There is a dentry refcount leak in devpts_get_tty.

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;

        up(&devpts_root->d_inode->i_sem);
        return tty;
}

The get_node function does a lookup on /dev/pts/<number> and returns the
dentry, taking a reference. We should dput the dentry after extracting
the tty pointer.

The attached patch does this.

Olaf
-- 
Olaf Kirch     |  The Hardware Gods hate me.
okir@xxxxxxx   |
---------------+ 
Index: v268/fs/devpts/inode.c
===================================================================
--- v268.orig/fs/devpts/inode.c
+++ v268/fs/devpts/inode.c
@@ -183,6 +183,7 @@ struct tty_struct *devpts_get_tty(int nu
 			dentry->d_inode->u.generic_ip;
 
 	up(&devpts_root->d_inode->i_sem);
+	dput(dentry);
 
 	return tty;
 }