From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Mon, 04 May 2026 15:39:49 +0200 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1wJtWY-000uUt-0X for lore@lore.pengutronix.de; Mon, 04 May 2026 15:39:49 +0200 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1wJtWW-0005YV-Nc for lore@pengutronix.de; Mon, 04 May 2026 15:39:49 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=9VOYh//6eYbHsCc7Kr7vUqj28RbhtJ2PTvC+JnF3qso=; b=p7KRsyUlvpwuH4AofxS2Hqo/Xs 8dWfELXU25+k44duilgDMrX3Qnqw254tqwlZ1rcCbPbmE3yiIp5VjmEQzIioRmTXPBSHqsXqcBU45 TmHB/o19Wm9Nb3N8D38T6RSwE0fttCrG41lCpTaTdeyMtrUWG+kCsIVpHNyl11fs7BGrEhbCjFNE0 uBmtd3Mz4/QFz0O3YlyfM3OYy3waNATd4nHrr/4N/NGGVLXNgXokMqak9oP+v68M0eHBf9evwFTtQ vOuV9U5NBHE2rIVFZH8aqOogAMekUtR0bzvdWMOK+6d9w3jWdB81X8Npeao8HI3AMGgNdqKDutJ8c PUaCPUxw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wJtW0-0000000DKdu-09dD; Mon, 04 May 2026 13:39:16 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wJtVw-0000000DKd5-2fWJ for barebox@lists.infradead.org; Mon, 04 May 2026 13:39:13 +0000 Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1wJtVt-0005Mu-99; Mon, 04 May 2026 15:39:09 +0200 Received: from pty.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::c5]) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1wJtVs-000Q7c-26; Mon, 04 May 2026 15:39:09 +0200 Received: from sha by pty.whiteo.stw.pengutronix.de with local (Exim 4.98.2) (envelope-from ) id 1wJtVs-0000000Gd2a-4A3u; Mon, 04 May 2026 15:39:09 +0200 Date: Mon, 4 May 2026 15:39:08 +0200 From: Sascha Hauer To: Ahmad Fatoum Cc: Marco Felsch , BAREBOX Message-ID: References: <20260428-env-autoprobe-v1-0-9cdedfa0752e@pengutronix.de> <20260428-env-autoprobe-v1-3-9cdedfa0752e@pengutronix.de> <12eb5638-f580-4b3b-9099-9d72ddeb4f16@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <12eb5638-f580-4b3b-9099-9d72ddeb4f16@pengutronix.de> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260504_063912_694846_3F9C4231 X-CRM114-Status: GOOD ( 36.76 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-5.1 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH 3/3] environment: add explicit option to allow searching for environment devices X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) On Mon, May 04, 2026 at 02:02:16PM +0200, Ahmad Fatoum wrote: > Hello, > > On 5/4/26 1:35 PM, Marco Felsch wrote: > > Hi Sascha, > > > > On 26-04-28, Sascha Hauer wrote: > >> Add an explicit Kconfig option to allow searching the environment storage path > >> based on the barebox environment partition GUID. > >> > >> So far this depended on CONFIG_INSECURE being set. First of all loading the > >> barebox environment from storage is always insecure as the barebox environment > >> doesn't have any security measures. > > It's possible to only allow environment loading after having verified > that the system is in development mode for example. > > Autoloading the environment can't be secured as you note. > > > >> The difference that comes with loading > >> the environment from an explicitly specified storage device and autoprobing > >> it from the available block devices is that with the former an attacker would > >> need access to the internal storage whereas with the latter barebox could > >> be tricked into loading an environment from an external SD card. > >> > >> Whether or not this is acceptable depends on the case, so ask the user for it. > >> > >> Real security can only be provided by not loading an environment from storage > >> at all, but that can be controlled at compile time by disabling CONFIG_ENV_HANDLING > >> or at runtime by security policies. > > > > TBH I actually don't see why this option can't follow the > > CONFIG_INSECURE. > > > > Since ENV handling is enabled you do pull the HAS_INSECURE_DEFAULTS=y. > > As you written above env handling is always insecure as of now. > > > > So it seems that you want to get rid of the CONFIG_INSECURE=y in your > > setup. The only users of this CONFIG switch are global_env_autoprobe and > > lib/random.c. Therefore my question, that I don't see why we can't stick > > with the CONFIG_INSECURE switch. > > I also don't understand Sascha's motivation here. > > You can add global.env.autoprobe=1 to your environment to opt-in despite > CONFIG_INSECURE being disabled. What's the new Kconfig option needed for? Maybe I was confused by that because it's evaluated in the wrong order. global.env.autoprobe is evaluated in default_environment_path_get() which is executed before the default environment is loaded. We could fix that with the cost of calling nvvar_load() twice, once with the default environment loaded and once again with the persistent environment loaded. That said, I think whether or not we load the environment by part UUID deserves its own decision, it shouldn't be hidden behind a generic option. Also it's not consistent to claim that loading environment by part UUID is insecure, but allowing it to be bypassed by setting global.env.autoprobe=1, as if that would make it secure. ENV_HANDLING_AUTOPROBE depends on ENV_HANDLING which itself selects HAS_INSECURE_DEFAULTS which indicates that an option is selected that has "potentially insecure defaults". Sounds consistent to me. Sascha -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |