From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935365Ab3BTQNI (ORCPT ); Wed, 20 Feb 2013 11:13:08 -0500 Received: from mail-ve0-f175.google.com ([209.85.128.175]:64242 "EHLO mail-ve0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934558Ab3BTQND (ORCPT ); Wed, 20 Feb 2013 11:13:03 -0500 Message-ID: <5124F600.9030908@redhat.com> Date: Wed, 20 Feb 2013 17:12:48 +0100 From: Paolo Bonzini User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 CC: linux-kernel@vger.kernel.org, Tejun Heo , "James E.J. Bottomley" , linux-scsi@vger.kernel.org, Jens Axboe Subject: Re: [PATCH v2 00/14] Corrections and customization of the SG_IO command whitelist (CVE-2012-4542) References: <1360163761-8541-1-git-send-email-pbonzini@redhat.com> In-Reply-To: <1360163761-8541-1-git-send-email-pbonzini@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Il 06/02/2013 16:15, Paolo Bonzini ha scritto: > This series regards the whitelist that is used for the SG_IO ioctl. This > whitelist has three problems: > > * the bitmap of allowed commands is designed for MMC devices (roughly, > "play/burn CDs without requiring root") but some opcodes overlap across SCSI > device classes and have different meanings for different classes. > > * also because the bitmap of allowed commands is designed for MMC devices > only, some commands are missing even though they are generally useful and > not insecure. At least not more insecure than anything else you can > do if you have access to /dev/sdX or /dev/stX nodes. > > * the whitelist can be disabled per-process but not per-disk. In addition, > the required capability (CAP_SYS_RAWIO) gives access to a range of other > resources, enough to make it insecure. > > The series corrects these problems. Patches 1-4 solve the first problem, > which also has an assigned CVE, by using different bitmaps for the various > device classes. Patches 5-11 solve the second by adding more commands > to the bitmaps. Patches 12 and 13 solve the third, and were already > posted but ignored by the maintainers despite multiple pings. > > Note: checkpatch hates the formatting of the command table. I know about this, > and ensured that there are no errors in the rest of the code. The current > formatting is IMHO quite handy, and roughly based on the files available > from the SCSI standard body. > > Ok for the next merge window? > > Paolo > > v1->v2: remove 2 MMC commands and 6 SBC commands (see patches 6 and 9 > for details). Added patch 14 and added a few more scanner > commands based on SANE (scanners are not whitelisted by default, > also were not in v1, but this makes it possible to opt into the > whitelist out of paranoia). Removed C++ comments. Removed the > large #if 0'd list of commands that the kernel does not pass > though. Marked blk_set_cmd_filter_defaults as __init. Ping... Jens/James, is anyone going to pick this up for 3.9? Paolo > > Paolo Bonzini (14): > sg_io: pass request_queue to blk_verify_command > sg_io: reorganize list of allowed commands > sg_io: use different default filters for each device class > sg_io: resolve conflicts between commands assigned to multiple > classes (CVE-2012-4542) > sg_io: whitelist a few more commands for rare & obsolete device types > sg_io: whitelist another command for multimedia devices > sg_io: whitelist a few more commands for media changers > sg_io: whitelist a few more commands for tapes > sg_io: whitelist a few more commands for disks > sg_io: whitelist a few obsolete commands > sg_io: mark blk_set_cmd_filter_defaults as __init > sg_io: remove remnants of sysfs SG_IO filters > sg_io: introduce unpriv_sgio queue flag > sg_io: use unpriv_sgio to disable whitelisting for scanners > > Documentation/block/queue-sysfs.txt | 8 + > block/blk-sysfs.c | 33 +++ > block/bsg.c | 2 +- > block/scsi_ioctl.c | 369 ++++++++++++++++++++++++++--------- > drivers/scsi/scsi_scan.c | 14 ++- > drivers/scsi/sg.c | 6 +- > include/linux/blkdev.h | 8 +- > include/linux/genhd.h | 9 - > include/scsi/scsi.h | 3 + > 9 files changed, 344 insertions(+), 108 deletions(-) >