linux-ext4 - Re: [PATCH V2] filefrag: count 0 extents properly when verbose

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-Id: <C30EEA83-4D04-44BE-A21E-696A6A4A735A@dilger.ca>
Date:	Sat, 7 May 2011 21:35:19 -0600
From:	Andreas Dilger <adilger@...ger.ca>
To:	Ted Ts'o <tytso@....edu>
Cc:	Eric Sandeen <sandeen@...hat.com>,
	ext4 development <linux-ext4@...r.kernel.org>
Subject: Re: [PATCH V2] filefrag: count 0 extents properly when verbose

I was going to comment on this on Friday and supply a new patch but got distracted. There is actually a cleaner way to implement this, by initializing the extent count to zero, and always incrementing it inside the inner loop. That simplifies the case when there are no extents returned by FIEMAP.

I'm sure I'll get around to sending an updated patch at some point, and will clean up this section at the same time. 

Cheers, Andreas

On 2011-05-07, at 4:45 PM, Ted Ts'o <tytso@....edu> wrote:

> On Thu, May 05, 2011 at 01:21:08PM -0500, Eric Sandeen wrote:
>> # rm -f a; touch a; filefrag a
>> /boot/a: 0 extents found
>> 
>> works properly, but
>> 
>> # rm -f a; touch a; filefrag -v a
>> Filesystem type is: ef53
>> Filesystem cylinder groups is approximately 61
>> File size of a is 0 (0 blocks, blocksize 1024)
>> ext logical physical expected length flags
>> a: 1 extent found
>> 
>> yields 1 extent when it should be 0.
>> 
>> Fix this up by special-casing no extents returned in verbose
>> mode; skip printing the header for the columns too, since there
>> are no columns to print.
>> 
>> Also, in nonverbose mode we can set fm_extent_count to 0
>> so that FIEMAP will just query the extent count without gathering
>> details; clarify this with a comment.
>> 
>> Addresses-redhat-bugzilla: 653234
>> Signed-off-by: Eric Sandeen <sandeen@...hat.com>
> 
> Thanks, 
> 
> applied to the maint branch (which will then get pulled to
> master/next) of e2fsprogs.
> 
>                    - Ted
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html