From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A2C7C433F5 for ; Tue, 1 Feb 2022 20:54:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229830AbiBAUyu (ORCPT ); Tue, 1 Feb 2022 15:54:50 -0500 Received: from mout.perfora.net ([74.208.4.194]:37099 "EHLO mout.perfora.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242571AbiBAUyc (ORCPT ); Tue, 1 Feb 2022 15:54:32 -0500 Received: from [10.93.3.78] ([206.193.5.9]) by mrelay.perfora.net (mreueus002 [74.208.5.2]) with ESMTPSA (Nemesis) id 0M39Wb-1mPVVW2xOR-00sucP; Tue, 01 Feb 2022 21:54:09 +0100 To: dalias@libc.org Cc: ariadne@dereferenced.org, ebiederm@xmission.com, keescook@chromium.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk References: <20220126132729.GA7942@brightrain.aerifal.cx> Subject: Re: [PATCH] fs/exec: require argv[0] presence in do_execveat_common() Reply-To: 20220126132729.GA7942@brightrain.aerifal.cx From: hypervis0r Message-ID: Date: Tue, 1 Feb 2022 12:54:08 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <20220126132729.GA7942@brightrain.aerifal.cx> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Provags-ID: V03:K1:XmjLVKZFEUDfEUNA/RKZbOxxM75jIPCUSbfld6c3g1t9YUgJ8aT L25f/+7Sd/2ekS4JobqXJMsop+ggDacZLHdw2veZtEN0d35ovRfwYpNWGOy5jZy31g9sSFm pmCDNHHDa5YF669+CX7svj/ACBtvvHjJ96Dopx1gG0oejvbVoiBbNZKP9XCcL7ozcOs7tQp QtM85Ad26cC+fX2fWNJwQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:dK0njNiz0ps=:ykgJZuiKj6dn/nIkZJh4w7 Rn4XETX9bhxWEYlO8S6vnic1lCccaregkglAYHcr2x4oMIUvYFHbaaeHT6XicnAvlQEKtZxUm DVm+/8ew6b2MEtd5jz2y38HCCWjRmvuL+Q4k4ti9gJjvTjjd269ayj9rusJsGjM+TtHz3wirI +51AlVHmsnLh9kkRD1JVO+u+KNOOhls9DDRFGnFSktBbSAuJp953d2a+tdfWRzSwru9lmUzn6 TdEDOkwIrOADaI3YkJEvRfF7ZQWqPuMOi+PBht0SDfuFHYyGdXlCiY3QW6mjjM0Z7vOp8GlSC z/pH2EcSJSqmH0MEZq8DFVkIPrN16nli2PpnDG37sc93MVF4Z9lUSS8noC9eV9J2YHQwLeFwo GRnwONr5rPZcDEaLyfUlnIcPI1RakJc1BGwfvDyZugr/FrdXpB/i+ZyDCH6SQ3OaVXqxQW6cM DeWoiB4nxnE++ZZBm8EjehzgtKSHS7a35jjdNtGfbjV9xzrUj2SJPH9mzpatHYNqiRNZMqXAV NEtkwmGwZlz4QtAwyRygwpKqmhHWhhctHb4FYktbLW8HrzmWGbhQsQPD6vc+JQ5+Sm9DWgEuQ /lKpMV2U5tXGK3LjltOeDNMXZCDnrOt47Tn/7vGHCjJbX4l5Afsxs1aGM1rzTYSamjJ4s+s2s 56xjjskE3/R9jZC+ePUF1Crn1kLJXhz59laA5NpifKYbbmuSC7XL4CCo+YJIGC2gPGkF9I8vS Zq4OUubXwvgVbZf4 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > I'm not really opposed to attempting to change this with consensus > (like, actually proposing it on the Austin Group tracker), but a less > invasive change would be just enforcing it for the case where exec is > a privilege boundary (suid/sgid/caps). There's really no motivation > for changing longstanding standard behavior in a > non-privilege-boundary case. I don't really see it as a matter of "maintaining standard behavior". there are very little uses for this ABI feature to be present and only serves to make applications harder to port between Linux and other *nix systems. The pros (major vulnerabilities like CVE-2021-4034) outweigh the cons (minor userland ABI change that only affects shellcode on shell-storm.org) in this particular scenario, and I am all for this patch.