[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20200210163627.GA1829035@rani.riverdale.lan>
Date: Mon, 10 Feb 2020 11:36:29 -0500
From: Arvind Sankar <nivedita@...m.mit.edu>
To: Arjan van de Ven <arjan@...ux.intel.com>
Cc: Peter Zijlstra <peterz@...radead.org>,
Kees Cook <keescook@...omium.org>,
Andy Lutomirski <luto@...capital.net>,
Kristen Carlson Accardi <kristen@...ux.intel.com>,
tglx@...utronix.de, mingo@...hat.com, bp@...en8.de, hpa@...or.com,
rick.p.edgecombe@...el.com, x86@...nel.org,
linux-kernel@...r.kernel.org, kernel-hardening@...ts.openwall.com
Subject: Re: [RFC PATCH 06/11] x86: make sure _etext includes function
sections
On Mon, Feb 10, 2020 at 07:54:58AM -0800, Arjan van de Ven wrote:
> >
> > I'll leave it to others to figure out the exact details. But afaict it
> > should be possible to have fine-grained-randomization and preserve the
> > workaround in the end.
> >
>
> the most obvious "solution" is to compile with an alignment of 4 bytes (so tight packing)
> and then in the randomizer preserve the offset within 32 bytes, no matter what it is
>
> that would get you an average padding of 16 bytes which is a bit more than now but not too insane
> (queue Kees' argument that tiny bits of padding are actually good)
>
With the patchset for adding the mbranches-within-32B-boundaries option,
the section alignment gets forced to 32. With function-sections that
means function alignment has to be 32 too.
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
