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From: Oliver Neukum <oliver@neukum.org>
To: Adrian Bunk <bunk@stusta.de>
Subject: Re: sysfs_drop_dentry(): possible NULL dereference
Date: Mon, 19 Mar 2007 11:09:56 +0100
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Am Montag, 19. März 2007 10:22 schrieb Adrian Bunk:

>  void sysfs_drop_dentry(struct sysfs_dirent * sd, struct dentry * parent)
>  {
>         struct dentry * dentry = sd->s_dentry;
> +       struct inode *inode;
>  
>         if (dentry) {
>                 spin_lock(&dcache_lock);
>                 spin_lock(&dentry->d_lock);
>                 if (!(d_unhashed(dentry) && dentry->d_inode)) {
> +                       inode = dentry->d_inode;
> +                       spin_lock(&inode->i_lock);
> ...
> 
> <--  snip  -->
> 
> If (!dentry->d_inode), then it's a NULL dereference.

As far as I can tell, sysfs being a virtual filesystem, does not use
dentries without inodes associated.

	Regards
		Oliver