linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Domenico Andreoli <domenico.andreoli@linux.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Linux PM <linux-pm@vger.kernel.org>,
	Linux Memory Management List <linux-mm@kvack.org>,
	linux-fsdevel@vger.kernel.org, mkleinsoft@gmail.com,
	Christoph Hellwig <hch@lst.de>,
	Andrew Morton <akpm@linux-foundation.org>,
	Len Brown <len.brown@intel.com>, Pavel Machek <pavel@ucw.cz>
Subject: Re: [PATCH v2] hibernate: Allow uswsusp to write to swap
Date: Sun, 22 Mar 2020 08:14:21 +0100	[thread overview]
Message-ID: <5202091.FuziMeULnI@kreacher> (raw)
In-Reply-To: <20200304170646.GA31552@dumbo>

On Wednesday, March 4, 2020 6:06:46 PM CET Domenico Andreoli wrote:
> From: Domenico Andreoli <domenico.andreoli@linux.com>
> 
> It turns out that there is one use case for programs being able to
> write to swap devices, and that is the userspace hibernation code.
> 
> Quick fix: disable the S_SWAPFILE check if hibernation is configured.
> 
> Fixes: dc617f29dbe5 ("vfs: don't allow writes to swap files")
> Reported-by: Domenico Andreoli <domenico.andreoli@linux.com>
> Reported-by: Marian Klein <mkleinsoft@gmail.com>
> Signed-off-by: Domenico Andreoli <domenico.andreoli@linux.com>
> 
> v2:
>  - use hibernation_available() instead of IS_ENABLED(CONFIG_HIBERNATE)
>  - make Fixes: point to the right commit

This looks OK to me.

Has it been taken care of already, or am I expected to apply it?

> ---
>  fs/block_dev.c |    4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> Index: b/fs/block_dev.c
> ===================================================================
> --- a/fs/block_dev.c
> +++ b/fs/block_dev.c
> @@ -34,6 +34,7 @@
>  #include <linux/task_io_accounting_ops.h>
>  #include <linux/falloc.h>
>  #include <linux/uaccess.h>
> +#include <linux/suspend.h>
>  #include "internal.h"
>  
>  struct bdev_inode {
> @@ -2001,7 +2002,8 @@ ssize_t blkdev_write_iter(struct kiocb *
>  	if (bdev_read_only(I_BDEV(bd_inode)))
>  		return -EPERM;
>  
> -	if (IS_SWAPFILE(bd_inode))
> +	/* uswsusp needs write permission to the swap */
> +	if (IS_SWAPFILE(bd_inode) && !hibernation_available())
>  		return -ETXTBSY;
>  
>  	if (!iov_iter_count(from))
> 






  parent reply	other threads:[~2020-03-22  7:14 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-04 17:06 [PATCH v2] hibernate: Allow uswsusp to write to swap Domenico Andreoli
2020-03-10  8:46 ` [hibernate] 3f423f3a03: xfstests.generic.570.fail kernel test robot
2020-03-10 16:16   ` Darrick J. Wong
2020-03-22  7:14 ` Rafael J. Wysocki [this message]
2020-03-22 11:23   ` [PATCH v2] hibernate: Allow uswsusp to write to swap Domenico Andreoli
2020-03-23 15:21     ` Darrick J. Wong
2020-03-24  2:19       ` Andrew Morton

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=5202091.FuziMeULnI@kreacher \
    --to=rjw@rjwysocki.net \
    --cc=akpm@linux-foundation.org \
    --cc=darrick.wong@oracle.com \
    --cc=domenico.andreoli@linux.com \
    --cc=hch@lst.de \
    --cc=len.brown@intel.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=mkleinsoft@gmail.com \
    --cc=pavel@ucw.cz \
    --cc=rafael@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).