linux-kernel - Re: module: preserve Elf information for livepatch modules

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <87a8o76h47.fsf@rustcorp.com.au>
Date:	Fri, 15 Jan 2016 06:58:08 +1030
From:	Rusty Russell <rusty@...tcorp.com.au>
To:	Jessica Yu <jeyu@...hat.com>
Cc:	Josh Poimboeuf <jpoimboe@...hat.com>,
	Seth Jennings <sjenning@...hat.com>,
	Jiri Kosina <jikos@...nel.org>,
	Vojtech Pavlik <vojtech@...e.com>,
	Jonathan Corbet <corbet@....net>,
	Miroslav Benes <mbenes@...e.cz>, linux-api@...r.kernel.org,
	live-patching@...r.kernel.org, x86@...nel.org,
	linux-kernel@...r.kernel.org, linux-s390@...r.kernel.org,
	linux-doc@...r.kernel.org
Subject: Re: module: preserve Elf information for livepatch modules

Jessica Yu <jeyu@...hat.com> writes:
> +++ Rusty Russell [11/01/16 11:55 +1030]:
>>This comment is a bit misleading: it's actually pointing into the
>>temporary module copy, which will be discarded.  The init section is
>>slightly different...
>
> Ah, perhaps I'm misunderstanding something..
>
> Since copy_module_elf() is called after move_module(), my
> understanding is that all the section sh_addr's should be pointing
> to either module core memory or module init memory (instead of the
> initial temporary copy of the module in info->hdr).

You're absolutely correct; I'd forgotten that particular kallsyms twist.

Sorry for the noise!
Rusty.