From: Luis Chamberlain <mcgrof@kernel.org>
To: axboe@kernel.dk, viro@zeniv.linux.org.uk,
gregkh@linuxfoundation.org, rostedt@goodmis.org,
mingo@redhat.com, jack@suse.cz, ming.lei@redhat.com,
nstange@suse.de
Cc: mhocko@suse.com, linux-block@vger.kernel.org,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
Luis Chamberlain <mcgrof@kernel.org>
Subject: [RFC 0/3] block: address blktrace use-after-free
Date: Wed, 1 Apr 2020 23:59:59 +0000 [thread overview]
Message-ID: <20200402000002.7442-1-mcgrof@kernel.org> (raw)
Upstream kernel.org korg#205713 contends that there is a UAF in
the core debugfs debugfs_remove() function, and has gone through
pushing for a CVE for this, CVE-2019-19770.
If correct then parent dentries are not positive, and this would
have implications far beyond this bug report. Thankfully, upon review
with Nicolai, he wasn't buying it. His suspicions that this was just
a blktrace issue were spot on, and this patch series demonstrates
that, provides a reproducer, and provides a solution to the issue.
We there would like to contend CVE-2019-19770 as invalid. The
implications suggested are not correct, and this issue is only
triggerable with root, by shooting yourself on the foot by misuing
blktrace.
If you want this on a git tree, you can get it from linux-next
20200401-blktrace-fix-uaf branch [2].
Wider review, testing, and rants are appreciated.
[0] https://bugzilla.kernel.org/show_bug.cgi?id=205713
[1] https://nvd.nist.gov/vuln/detail/CVE-2019-19770
[2] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git/log/?h=20200401-blktrace-fix-uaf
Luis Chamberlain (3):
block: move main block debugfs initialization to its own file
blktrace: fix debugfs use after free
block: avoid deferral of blk_release_queue() work
block/Makefile | 1 +
block/blk-core.c | 9 +--------
block/blk-debugfs.c | 27 +++++++++++++++++++++++++++
block/blk-mq-debugfs.c | 5 -----
block/blk-sysfs.c | 21 ++++++++-------------
block/blk.h | 17 +++++++++++++++++
include/linux/blktrace_api.h | 1 -
kernel/trace/blktrace.c | 19 ++++++++-----------
8 files changed, 62 insertions(+), 38 deletions(-)
create mode 100644 block/blk-debugfs.c
--
2.25.1
next reply other threads:[~2020-04-02 0:00 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-01 23:59 Luis Chamberlain [this message]
2020-04-02 0:00 ` [RFC 1/3] block: move main block debugfs initialization to its own file Luis Chamberlain
2020-04-05 3:12 ` Bart Van Assche
2020-04-06 14:23 ` Luis Chamberlain
2020-04-02 0:00 ` [RFC 2/3] blktrace: fix debugfs use after free Luis Chamberlain
2020-04-02 1:57 ` Eric Sandeen
2020-04-02 16:14 ` Luis Chamberlain
2020-04-05 3:39 ` Bart Van Assche
2020-04-06 1:27 ` Eric Sandeen
2020-04-06 4:25 ` Bart Van Assche
2020-04-06 9:18 ` Nicolai Stange
2020-04-06 15:19 ` Luis Chamberlain
2020-04-07 8:15 ` Luis Chamberlain
2020-04-06 14:29 ` Eric Sandeen
2020-04-07 8:09 ` Luis Chamberlain
2020-04-06 15:14 ` Luis Chamberlain
2020-04-02 0:00 ` [RFC 3/3] block: avoid deferral of blk_release_queue() work Luis Chamberlain
2020-04-02 3:39 ` Bart Van Assche
2020-04-02 14:49 ` Nicolai Stange
2020-04-06 9:11 ` Nicolai Stange
2020-04-09 18:11 ` Luis Chamberlain
2020-04-02 7:44 ` [RFC 0/3] block: address blktrace use-after-free Greg KH
2020-04-03 8:19 ` Ming Lei
2020-04-03 14:06 ` Luis Chamberlain
2020-04-03 14:13 ` Bart Van Assche
2020-04-03 19:49 ` Luis Chamberlain
2020-04-07 2:47 ` yukuai (C)
2020-04-07 19:00 ` Luis Chamberlain
2020-04-09 20:59 ` Luis Chamberlain
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=20200402000002.7442-1-mcgrof@kernel.org \
--to=mcgrof@kernel.org \
--cc=axboe@kernel.dk \
--cc=gregkh@linuxfoundation.org \
--cc=jack@suse.cz \
--cc=linux-block@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mhocko@suse.com \
--cc=ming.lei@redhat.com \
--cc=mingo@redhat.com \
--cc=nstange@suse.de \
--cc=rostedt@goodmis.org \
--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).