From mboxrd@z Thu Jan  1 00:00:00 1970
From: Theodore Ts'o <tytso@mit.edu>
Subject: Re: filefrag: Fix segfault on virtual fs
Date: Sat, 28 Jul 2012 17:43:12 -0400
Message-ID: <20120728214312.GA8073@thunk.org>
References: <4FE9C02C.8040703@redhat.com>
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Cc: ext4 development <linux-ext4@vger.kernel.org>, maxnet@onlinehome.de
To: Eric Sandeen <sandeen@redhat.com>
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On Tue, Jun 26, 2012 at 03:59:08AM -0000, Eric Sandeen wrote:
> filefrag on a virtual fs like proc segfaults:
> 
> # filefrag /proc/filesystems 
> Floating point exception
> 
> because stat.f_blocks is 0, so the calculation of cylgroups is 0,
> which leads to a divide by 0 when calculating expected extents.
> 
> Since it's only used for ext2 filesystems anyway, just move
> the calculation of expected under "if (is_ext2)" to fix this.
> 
> Reported-by: Max Beikirch <maxnet@onlinehome.de>
> Signed-off-by: Eric Sandeen <sandeen@redhat.com>

Applied, thanks.

					- Ted