From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2C583208CF for ; Wed, 11 Oct 2023 15:59:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="kOdm9yp7" Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 69475A4 for ; Wed, 11 Oct 2023 08:59:15 -0700 (PDT) Received: by mail-pl1-x62d.google.com with SMTP id d9443c01a7336-1c9b7c234a7so16449625ad.3 for ; Wed, 11 Oct 2023 08:59:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1697039955; x=1697644755; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=4EBM6QELn8ef1132SlMYb+b5mnbgclrgGpye79FUDoA=; b=kOdm9yp70z5nFVU+0weI+1eg23cIaj25FheAboD6zB4zEnLNzmjeqLn9MjCX/uc7v0 C4/BKUtrAVht43EvwZkJQlK7bkNv49u2D9En5mm7ez9Bc55zKqCdToKmdE8T3Lw6rRpc IHTxWGl5ZiImOeL93KfhJVcgwO8RBsSsUtx1I= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697039955; x=1697644755; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=4EBM6QELn8ef1132SlMYb+b5mnbgclrgGpye79FUDoA=; b=HctnjsHO1jMlsLVW+HzaPH+o1E/A+TFNpLxyZgPGc77May5D+XN434y2L/mhh+GaEg KdTTj/z4i31Bicr5VQ3ZIwyb2kWnzLyPn9vfiUk0Ipn9tHd69wGOMoVZOtY/Ddm75P7b gasMqRy5QgwneZtkVaBjL9Q8EuyES3EDkqqSbmTXHv/+ZThQEsj1/jHFWk9VL2Rlw5it n9du1o94OsSOlxmZ/F4pLgofVfmxhwAtwB6tLiYEQ9uO1ZZdiPtICiVBLctv6LKZuNzv VuV2hmKWLX+0y4l4biPmpkVWxU5cEgmWU5IQHkYlHMignum27SU+5UE2zUaJPsSnbLlg jV9Q== X-Gm-Message-State: AOJu0YyMmulN7HBhMyKOHgB5uSzIT36YAlKCWmNRh5w0282PIlChmFXi yWCNHFMezblTxXsEAlh4b+lPUfSSjZfydyU5A/8= X-Google-Smtp-Source: AGHT+IFnhzRKmMknQABhdyRSLqQ/OlvokCEslWYllvOvh9DztjV2jkf9w6Z8A6ji3ZgSPg2SoS9dEQ== X-Received: by 2002:a17:902:d716:b0:1c7:37e2:13e5 with SMTP id w22-20020a170902d71600b001c737e213e5mr18437786ply.21.1697039954910; Wed, 11 Oct 2023 08:59:14 -0700 (PDT) Received: from www.outflux.net (198-0-35-241-static.hfc.comcastbusiness.net. [198.0.35.241]) by smtp.gmail.com with ESMTPSA id u7-20020a170902b28700b001c46d04d001sm9681plr.87.2023.10.11.08.59.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Oct 2023 08:59:14 -0700 (PDT) Date: Wed, 11 Oct 2023 08:59:12 -0700 From: Kees Cook To: Alyssa Ross Cc: Alexander Viro , Christian Brauner , Tetsuo Handa , Eric Biederman , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] exec: allow executing block devices Message-ID: <202310110857.522FAFCA@keescook> References: <20231010092133.4093612-1-hi@alyssa.is> <202310101535.CEDA4DB84@keescook> <87o7h5vcao.fsf@alyssa.is> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87o7h5vcao.fsf@alyssa.is> X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Wed, Oct 11, 2023 at 07:38:39AM +0000, Alyssa Ross wrote: > Is it possible to have a file-backed memfd? Strange name if so! Not that I'm aware, but a program could just read the ELF from the block device and stick it in a memfd and execute the result. -- Kees Cook