From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:58376 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752658AbcLLWrI (ORCPT ); Mon, 12 Dec 2016 17:47:08 -0500 Subject: Patch "device-dax: fix private mapping restriction, permit read-only" has been added to the 4.8-stable tree To: dan.j.williams@intel.com, dave.hansen@linux.intel.com, gregkh@linuxfoundation.org, hughd@google.com, pawel.lebioda@intel.com Cc: , From: Date: Mon, 12 Dec 2016 14:47:18 -0800 Message-ID: <148158283870135@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled device-dax: fix private mapping restriction, permit read-only to the 4.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: device-dax-fix-private-mapping-restriction-permit-read-only.patch and it can be found in the queue-4.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 325896ffdf90f7cbd59fb873b7ba20d60d1ddf3c Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 6 Dec 2016 17:03:35 -0800 Subject: device-dax: fix private mapping restriction, permit read-only From: Dan Williams commit 325896ffdf90f7cbd59fb873b7ba20d60d1ddf3c upstream. Hugh notes in response to commit 4cb19355ea19 "device-dax: fail all private mapping attempts": "I think that is more restrictive than you intended: haven't tried, but I believe it rejects a PROT_READ, MAP_SHARED, O_RDONLY fd mmap, leaving no way to mmap /dev/dax without write permission to it." Indeed it does restrict read-only mappings, switch to checking VM_MAYSHARE, not VM_SHARED. Cc: Dave Hansen Cc: Pawel Lebioda Fixes: 4cb19355ea19 ("device-dax: fail all private mapping attempts") Reported-by: Hugh Dickins Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman --- drivers/dax/dax.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/dax/dax.c +++ b/drivers/dax/dax.c @@ -324,7 +324,7 @@ static int check_vma(struct dax_dev *dax return -ENXIO; /* prevent private mappings from being established */ - if ((vma->vm_flags & VM_SHARED) != VM_SHARED) { + if ((vma->vm_flags & VM_MAYSHARE) != VM_MAYSHARE) { dev_info(dev, "%s: %s: fail, attempted private mapping\n", current->comm, func); return -EINVAL; Patches currently in stable-queue which might be from dan.j.williams@intel.com are queue-4.8/device-dax-fix-private-mapping-restriction-permit-read-only.patch