lkml.org 
[lkml]   [2010]   [Oct]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 1/2] vfs: fix overflow in direct-io subsystem
On Wed, 13 Oct 2010 22:45:57 +0200
Edward Shishkin <edward.shishkin@gmail.com> wrote:

> Fix up overflow (ssize_t->int) in the direct-io subsystem.
>
> Signed-off-by: Edward Shishkin <edward@redhat.com>
> ---
> fs/direct-io.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> --- linux-2.6.36-rc7.orig/fs/direct-io.c
> +++ linux-2.6.36-rc7/fs/direct-io.c
> @@ -218,7 +218,7 @@ static struct page *dio_get_page(struct
> * filesystems can use it to hold additional state between get_block calls and
> * dio_complete.
> */
> -static int dio_complete(struct dio *dio, loff_t offset, int ret, bool is_async)
> +static ssize_t dio_complete(struct dio *dio, loff_t offset, ssize_t ret, bool is_async)
> {
> ssize_t transferred = 0;
>

I'd call this a truncation error, not an overflow. Semantics.

So what's the runtime effect? The subsystem will go stupid when doing
a single transfer of over 2G on a 64-bit machine?

Can this actually happen in practice? Has nobody ever done this before
now?

<goes to test it>

<discovers that ubuntu 8.04's dd doesn't support conv=direct>

<stupid thing>


\
 
 \ /
  Last update: 2010-10-15 01:23    [W:0.038 / U:0.616 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site