Linux-mm Archive on lore.kernel.org
 help / color / Atom feed
From: Davidlohr Bueso <dave@stgolabs.net>
To: akpm@linux-foundation.org, aarcange@redhat.com
Cc: joe.lawrence@redhat.com, gareth.evans@contextis.co.uk,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	dave@stgolabs.net, stable@kernel.org
Subject: [PATCH -next 0/2] ipc/shm: shmat() fixes around nil-page
Date: Thu,  3 May 2018 13:32:41 -0700
Message-ID: <20180503203243.15045-1-dave@stgolabs.net> (raw)

Hi,

These patches fix two issues reported[1] a while back by Joe and Andrea
around how shmat(2) behaves with nil-page.

The first reverts a commit that it was incorrectly thought that mapping
nil-page (address=0) was a no no with MAP_FIXED. This is not the case,
with the exception of SHM_REMAP; which is address in the second patch.

I chose two patches because it is easier to backport and it explicitly
reverts bogus behaviour. Both patches ought to be in -stable and ltp
testcases need updated (the added testcase around the cve can be modified
to just test for SHM_RND|SHM_REMAP).

[1] lkml.kernel.org/r/20180430172152.nfa564pvgpk3ut7p@linux-n805

Thanks! 

Davidlohr Bueso (2):
  Revert "ipc/shm: Fix shmat mmap nil-page protection"
  ipc/shm: fix shmat() nil address after round-down when remapping

 ipc/shm.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

-- 
2.13.6

             reply index

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-03 20:32 Davidlohr Bueso [this message]
2018-05-03 20:32 ` [PATCH 1/2] Revert "ipc/shm: Fix shmat mmap nil-page protection" Davidlohr Bueso
2018-05-03 20:49 ` [PATCH 2/2] ipc/shm: fix shmat() nil address after round-down when remapping Davidlohr Bueso
2018-05-10 18:17 ` [PATCH -next 0/2] ipc/shm: shmat() fixes around nil-page Vlastimil Babka
2018-05-14 16:19   ` Davidlohr Bueso

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=20180503203243.15045-1-dave@stgolabs.net \
    --to=dave@stgolabs.net \
    --cc=aarcange@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=gareth.evans@contextis.co.uk \
    --cc=joe.lawrence@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=stable@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

Linux-mm Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-mm/0 linux-mm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-mm linux-mm/ https://lore.kernel.org/linux-mm \
		linux-mm@kvack.org
	public-inbox-index linux-mm

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kvack.linux-mm


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git