From: Arnd Bergmann <arnd@arndb.de>
Subject: Re: [PATCH] d_ino considered harmful
Date: Wed, 16 Jun 2010 21:10:42 +0200
Message-ID: <201006162110.43322.arnd@arndb.de>
References: <20100616185913.GA15566@shell>
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Cc: Alexander Viro <viro@zeniv.linux.org.uk>,
	Christoph Hellwig <hch@infradead.org>,
	Miklos Szeredi <miklos@szeredi.hu>,
	Jan Blunck <jblunck@suse.de>,
	Jamie Lokier <jamie@shareable.org>,
	David Woodhouse <dwmw2@infradead.org>,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
To: Valerie Aurora <vaurora@redhat.com>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <20100616185913.GA15566@shell>
Sender: linux-kernel-owner@vger.kernel.org
List-Id: linux-fsdevel.vger.kernel.org

On Wednesday 16 June 2010 20:59:13 Valerie Aurora wrote:
> @@ -91,7 +91,9 @@ static int fillonedir(void * __buf, const char * name, int namlen, loff_t offset
>  
>         if (buf->result)
>                 return -EINVAL;
> -       d_ino = ino;
> +       /* Use of d_ino without st_dev is always buggy. */
> +       d_ino = 0;
> +
>         if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
>                 buf->result = -EOVERFLOW;
>                 return -EOVERFLOW;

Isn't this just the path taken by sys_oldreaddir?

Glibc (at least on my box) translates all user calls to readdir into
sys_getdents or sys_getdents64, so I think you'd also need to change
filldir() and filldir64() for your testing.

	Arnd