linux-ext4 - Re: ext3: deleting files doesn't free up space

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 for Android: free password hash cracker in your pocket

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

Message-ID: <4D2AA2E9.9030209@uw.no>
Date:	Mon, 10 Jan 2011 06:10:49 +0000
From:	"Daniel K." <dk@...no>
To:	Dan Carpenter <error27@...il.com>
CC:	LKML <linux-kernel@...r.kernel.org>, linux-ext4@...r.kernel.org
Subject: Re: ext3: deleting files doesn't free up space

Dan Carpenter wrote:
> I filled up my partition last night.
> I deleted 5 gigs of movies.
> The "Used" number went down to 125G.
> The "Free" number stayed at 0.
> I rebooted the system but it's still the same.
> 
> $ echo foo > foo
> bash: echo: write error: No space left on device
> 
> $ df .
> Filesystem           1K-blocks      Used Available Use% Mounted on
> /dev/sda1            136236548 130363620         0 100% /media/old_sys

Check out the -m option to tune2fs, which sets the reserved-blocks-percentage for the FS - the percentage of blocks reserved to the super user, which is 5% by default.

Presumably, root has filled the partition completely, and 5G worth of deleted user data is not enough to get under the 5% limit to allow for new data to be written by users.

As this partition is used for /home you might as well turn the feature off, as root should not need to have space reserved in that area of the filesystem.

	tune2fs -m 0 /dev/sda1

should give regular users access to the reserved blocks.

Daniel K.
--
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