From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: hch@infradead.org, akpm@linux-foundation.org, tytso@mit.edu,
viro@zeniv.linux.org.uk, darrick.wong@oracle.com
Cc: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: [PATCH v2 0/2] vfs: make active swap files unwritable
Date: Fri, 28 Jun 2019 11:35:11 -0700 [thread overview]
Message-ID: <156174691124.1557844.14293659081769020256.stgit@magnolia> (raw)
Hi all,
I discovered that it's possible for userspace to write to active swap
files and swap devices. While activated, the kernel effectively holds
an irrevocable (except by swapoff) longterm lease on the storage
associated with the swap device, so we need to shut down this vector for
memory corruption of userspace programs.
If you're going to start using this mess, you probably ought to just
pull from my git trees, which are linked below.
This has been lightly tested with fstests. Enjoy!
Comments and questions are, as always, welcome.
--D
kernel git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfs-linux.git/log/?h=immutable-swapfiles
fstests git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfstests-dev.git/log/?h=immutable-swapfiles
next reply other threads:[~2019-06-28 18:35 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-28 18:35 Darrick J. Wong [this message]
2019-06-28 18:35 ` [PATCH 1/2] mm: set S_SWAPFILE on blockdev swap devices Darrick J. Wong
2019-06-28 18:35 ` [PATCH 2/2] vfs: don't allow writes to swap files Darrick J. Wong
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=156174691124.1557844.14293659081769020256.stgit@magnolia \
--to=darrick.wong@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=hch@infradead.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-xfs@vger.kernel.org \
--cc=tytso@mit.edu \
--cc=viro@zeniv.linux.org.uk \
/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).