From: Aleksa Sarai <cyphar@cyphar.com>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>,
Eric Biederman <ebiederm@xmission.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
stable@vger.kernel.org,
Christian Brauner <christian.brauner@ubuntu.com>,
Serge Hallyn <serge@hallyn.com>,
dev@opencontainers.org, containers@lists.linux-foundation.org,
linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH RFC 0/1] mount: universally disallow mounting over symlinks
Date: Mon, 30 Dec 2019 16:49:13 +1100 [thread overview]
Message-ID: <20191230054913.c5avdjqbygtur2l7@yavin.dot.cyphar.com> (raw)
In-Reply-To: <20191230054413.GX4203@ZenIV.linux.org.uk>
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On 2019-12-30, Al Viro <viro@zeniv.linux.org.uk> wrote:
> On Mon, Dec 30, 2019 at 04:20:35PM +1100, Aleksa Sarai wrote:
>
> > A reasonably detailed explanation of the issues is provided in the patch
> > itself, but the full traces produced by both the oopses and deadlocks is
> > included below (it makes little sense to include them in the commit since we
> > are disabling this feature, not directly fixing the bugs themselves).
> >
> > I've posted this as an RFC on whether this feature should be allowed at
> > all (and if anyone knows of legitimate uses for it), or if we should
> > work on fixing these other kernel bugs that it exposes.
>
> Umm... Are all of those traces
> a) reproducible on mainline and
This was on viro/for-next, I'll retry it on v5.5-rc4.
> b) reproducible as the first oopsen?
The NULL and garbage pointer derefs are reproducible as the first oops.
Looking at my logs, it looks like the deadlocks were always triggered
after the oops, but that might just have been a mistake on my part while
testing things.
> As it is, quite a few might be secondary results of earlier memory
> corruption...
Yeah, I thought that might be the case but decided to include them
anyway (the /proc/self/stack RCU stall is definitely the result of other
corruption and stalls).
--
Aleksa Sarai
Senior Software Engineer (Containers)
SUSE Linux GmbH
<https://www.cyphar.com/>
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next prev parent reply other threads:[~2019-12-30 5:49 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-30 5:20 [PATCH RFC 0/1] mount: universally disallow mounting over symlinks Aleksa Sarai
2019-12-30 5:20 ` [PATCH RFC 1/1] " Aleksa Sarai
2019-12-30 7:34 ` Linus Torvalds
2019-12-30 8:28 ` Aleksa Sarai
2020-01-08 4:39 ` Andy Lutomirski
2019-12-30 5:44 ` [PATCH RFC 0/1] " Al Viro
2019-12-30 5:49 ` Aleksa Sarai [this message]
2019-12-30 7:29 ` Aleksa Sarai
2019-12-30 7:53 ` Linus Torvalds
2019-12-30 8:32 ` Aleksa Sarai
2020-01-02 8:58 ` David Laight
2020-01-02 9:09 ` Aleksa Sarai
2020-01-01 0:43 ` Al Viro
2020-01-01 0:54 ` Al Viro
2020-01-01 3:08 ` Al Viro
2020-01-01 14:44 ` Aleksa Sarai
2020-01-01 23:40 ` Al Viro
2020-01-02 3:59 ` Aleksa Sarai
2020-01-03 1:49 ` Al Viro
2020-01-04 4:46 ` Ian Kent
2020-01-08 3:13 ` Al Viro
2020-01-08 3:54 ` Linus Torvalds
2020-01-08 21:34 ` Al Viro
2020-01-10 0:08 ` Linus Torvalds
2020-01-10 4:15 ` Al Viro
2020-01-10 5:03 ` Linus Torvalds
2020-01-10 6:20 ` Ian Kent
2020-01-12 21:33 ` Al Viro
2020-01-13 2:59 ` Ian Kent
2020-01-14 0:25 ` Ian Kent
2020-01-14 4:39 ` Al Viro
2020-01-14 5:01 ` Ian Kent
2020-01-14 5:59 ` Ian Kent
2020-01-10 21:07 ` Aleksa Sarai
2020-01-14 4:57 ` Al Viro
2020-01-14 5:12 ` Al Viro
2020-01-14 20:01 ` Aleksa Sarai
2020-01-15 14:25 ` Al Viro
2020-01-15 14:29 ` Aleksa Sarai
2020-01-15 14:34 ` Aleksa Sarai
2020-01-15 14:48 ` Al Viro
2020-01-15 13:57 ` Aleksa Sarai
2020-01-19 3:14 ` [RFC][PATCHSET][CFT] pathwalk cleanups and fixes Al Viro
2020-01-19 14:33 ` Ian Kent
2020-01-10 23:19 ` [PATCH RFC 0/1] mount: universally disallow mounting over symlinks Al Viro
2020-01-13 1:48 ` Ian Kent
2020-01-13 3:54 ` Al Viro
2020-01-13 6:00 ` Ian Kent
2020-01-13 6:03 ` Ian Kent
2020-01-13 13:30 ` Al Viro
2020-01-14 7:25 ` Ian Kent
2020-01-14 12:17 ` Ian Kent
2020-01-04 5:52 ` Andy Lutomirski
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