From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id ED21F3858C83; Wed, 15 Mar 2023 05:34:03 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org ED21F3858C83 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1678858443; bh=Q6D3zKtONhZyB7Vjh/8FbbbbgUEiknPOKPOf/7rbo9w=; h=From:To:Subject:Date:In-Reply-To:References:From; b=ETb5E7oaBPzj0MQvu9wihGjmGYzBw6JcQmDrKI9WzMlxThzQXRK5f9ymgzWbsWMrm mMfhxAlMoYioRcb52L6C32b5BgSVkKxG1C3FlUAa5/dW+jyc91f7pMe7rxRk7k/Ixa oW5zFJZ2m6j+8vNT5DdGsey5eHyCztvv+R7XMyh0= From: "janderson at rice dot edu" To: glibc-bugs@sourceware.org Subject: [Bug dynamic-link/30127] [rfe]: enable ld audit at run-time Date: Wed, 15 Mar 2023 05:34:03 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: dynamic-link X-Bugzilla-Version: 2.38 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: janderson at rice dot edu X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: security- X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://sourceware.org/bugzilla/show_bug.cgi?id=3D30127 --- Comment #49 from Jonathon Anderson --- (In reply to Stas Sergeev from comment #46) > So let me summarize that memfd_create() > (shm_open() actually) is not a replacement, > but rather is an essential part of the > scheme. Using it together with la_premap_dlmem() > and la_premap() you can get the desired > picture. Desired picture is 2 identical > mappings of the same lib, one at relolc_addr, > one at mmap_addr=3Dreloc_addr+VM_window_start. >=20 > There is basically nothing else! > That scheme is very simple to describe, > but not that simple to grok from that > description, as no one have tried that > layout yet. FWIW I understand this succinct description of your intended use case much better than your prior descriptions, thanks. If this is the core feature you need, then I see where most of my questions about the VM go off-topic. Sorry for the noise. (I honestly thought you were trying to achieve something far more drastic...) So in short, dynamic auditor loading is merely a "detail" in your full approach, since you don't have access to the executable or pre-launch environment and your patch to implement this core feature uses LD_AUDIT to = host the object mmap callback. I'll redirect my thoughts that are really about object mapping over to https://sourceware.org/bugzilla/show_bug.cgi?id=3D30007. I think it makes s= ense to resolve that RFE first, since that is in fact the core feature you need = for your entire approach to function. After (or maybe in parallel with) that we= can continue to discuss dynamic auditor loading over here. (In reply to Stas Sergeev from comment #47) > But regarding the dlmem()&co impl itself - > I'll rewrite it when this dlload_audit_module() > patch settles, as I definitely know more > about glibc than back when dlmem() was written. > So no need to look into it or criticise > it just yet. :) If you do look, please > restrict to a test-cases. Certainly, I'll stick to the API and test cases. :D --=20 You are receiving this mail because: You are on the CC list for the bug.=