Messages in this thread | | | Date | Sun, 24 Feb 2008 07:57:52 +0100 | From | Jörn Engel <> | Subject | Re: jffs2: -ENOSPC when truncating file?! |
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On Sun, 24 February 2008 09:36:07 +0900, David Woodhouse wrote: > On Sun, 2008-02-24 at 00:57 +0100, Pavel Machek wrote: > > > > I'm trying to free space by truncating big file, and I get: > > > > root@fic-gta01:~# ls -al gps.nmea > > -rw-r--r-- 1 root root 2332070 Feb 19 22:13 gps.nmea > > root@fic-gta01:~# > gps.nmea > > -sh: cannot create gps.nmea: No space left on device > > root@fic-gta01:~# rm gps.nmea > > root@fic-gta01:~# > gps.nmea > > root@fic-gta01:~# > > You need to write a log entry indicating the new length of the file. > There is no space for new log entries. > > There is a special case for removal -- 'rm gps.nmea' would work. Perhaps > we should add a special case for truncation too, so that it can also use > the extra pool of free space.
Could a naïve implementation of this get exploited by doing a large number of truncates that just shave single bytes off various files?
Looks like the safe way to do it would be to write out a replacement node for the truncated node, if the special case ever triggers.
Jörn
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