Re: [PATCH] eCryptfs: Delay writing 0's after llseek until write

Nish Aravamudan
2007-05-22T15:01:37Z

On 5/22/07, Michael Halcrow <mhalcrow@us.ibm.com> wrote:
> On Mon, May 21, 2007 at 09:07:08PM -0700, Andrew Morton wrote:
> > On Mon, 21 May 2007 18:00:21 -0500 Michael Halcrow <mhalcrow@us.ibm.com> wrote:
> >
> > > Delay writing 0's out in eCryptfs after a seek past the end of the
> > > file until data is actually written.
> >
> > a) why?
>
> http://www.opengroup.org/onlinepubs/009695399/functions/lseek.html
>
> ``The lseek() function shall not, by itself, extend the size of a
> file.''
>
> > b) what is the impact upon a user of them not having this patch?
>
> Applications that lseek() past the end of the file without writing
> will experience unexpected behavior.

FWIW, I believe Andrew's point was that critical information for Joe
Enduser (and Joe Patch-Ho) was lacking in the original changelog.

Thanks,
Nish