From: Kees Cook <keescook@chromium.org>
To: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
linux-hardening@vger.kernel.org
Subject: Re: [PATCH] alloc_tag: Tighten file permissions on /proc/allocinfo
Date: Thu, 25 Apr 2024 13:57:57 -0700 [thread overview]
Message-ID: <202404251356.F694909C63@keescook> (raw)
In-Reply-To: <w6nbxvxt3itugrvtcvnayj5ducoxifwbffd7qh6vcastw77mse@2ugphwusgttz>
On Thu, Apr 25, 2024 at 04:45:51PM -0400, Kent Overstreet wrote:
> On Thu, Apr 25, 2024 at 01:08:50PM -0700, Kees Cook wrote:
> > The /proc/allocinfo file exposes a tremendous about of information about
> > kernel build details, memory allocations (obviously), and potentially
> > even image layout (due to ordering). As this is intended to be consumed
> > by system owners (like /proc/slabinfo), use the same file permissions as
> > there: 0400.
>
> The side effect of locking down more and more reporting interfaces is
> that programs that consume those interfaces now have to run as root.
I'm fine if you want to tie it to some existing capability, but it
shouldn't be world-readable. Also, plenty of diagnostic tools already
either run as root or open whatever files they need to before dropping
privs.
--
Kees Cook
prev parent reply other threads:[~2024-04-25 20:58 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-25 20:08 Kees Cook
2024-04-25 20:45 ` Kent Overstreet
2024-04-25 20:51 ` Matthew Wilcox
2024-04-25 21:04 ` Kent Overstreet
2024-04-25 21:21 ` Suren Baghdasaryan
2024-04-25 21:25 ` Kent Overstreet
2024-04-25 21:38 ` Andrew Morton
2024-04-25 21:45 ` Kent Overstreet
2024-04-26 8:32 ` Pavel Machek
2024-04-26 8:46 ` Kent Overstreet
2024-04-25 22:42 ` Kees Cook
2024-04-25 23:02 ` Kent Overstreet
2024-04-25 23:47 ` Andrew Morton
2024-04-26 0:27 ` Kent Overstreet
2024-04-26 0:43 ` Kees Cook
2024-04-26 0:58 ` Kent Overstreet
2024-04-26 3:25 ` Matthew Wilcox
2024-04-26 3:35 ` Kent Overstreet
2024-04-26 8:34 ` Pavel Machek
2024-04-26 0:39 ` Kees Cook
2024-04-25 20:57 ` Kees Cook [this message]
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