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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0DA17C43381 for ; Mon, 1 Apr 2019 18:54:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CE7C62086C for ; Mon, 1 Apr 2019 18:54:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=hansenpartnership.com header.i=@hansenpartnership.com header.b="oKIcWEte" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728863AbfDASyq (ORCPT ); Mon, 1 Apr 2019 14:54:46 -0400 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:34888 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728690AbfDASyq (ORCPT ); Mon, 1 Apr 2019 14:54:46 -0400 Received: from localhost (localhost [127.0.0.1]) by bedivere.hansenpartnership.com (Postfix) with ESMTP id 758698EE12C; Mon, 1 Apr 2019 11:54:45 -0700 (PDT) Received: from bedivere.hansenpartnership.com ([127.0.0.1]) by localhost (bedivere.hansenpartnership.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xYMDqoXhVfSC; Mon, 1 Apr 2019 11:54:45 -0700 (PDT) Received: from [153.66.254.194] (unknown [50.35.68.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by bedivere.hansenpartnership.com (Postfix) with ESMTPSA id A7DA18EE0CD; Mon, 1 Apr 2019 11:54:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=hansenpartnership.com; s=20151216; t=1554144885; bh=jywvzMZ3T1LUMchw4h1QJoeQmzI1zyDJABogHdLRFlU=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=oKIcWEteat8kFuHGz/OoCpFcFXbGgmU+H5SLdNaptS6WmpEHgBYqDpIIMlvxPEwz+ Yd3/loKr40Al//wRDsBvRVSNjzaxE0URHf9EZdQzn2OQpZSrxSFmdkQvU9Rj71EFxt dw+D+XuGiBShlCdQi2IKkXkHmM1eLDRXV8zo4C98= Message-ID: <1554144883.3029.20.camel@HansenPartnership.com> Subject: Re: [PATCH v2] tpm: Actually fail on TPM errors during "get random" From: James Bottomley To: Kees Cook , Jarkko Sakkinen Cc: Jason Gunthorpe , Phil Baker , Craig Robson , Laura Abbott , Tomas Winkler , Nayna Jain , linux-kernel@vger.kernel.org, Peter Huewe , Arnd Bergmann , linux-integrity@vger.kernel.org Date: Mon, 01 Apr 2019 11:54:43 -0700 In-Reply-To: <20190401185219.GA22215@beast> References: <20190401185219.GA22215@beast> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Mon, 2019-04-01 at 11:52 -0700, Kees Cook wrote: > @@ -559,6 +559,9 @@ int tpm1_get_random(struct tpm_chip *chip, u8 > *dest, size_t max) > rc = total ? (int)total : -EIO; > out: > tpm_buf_destroy(&buf); > +fail: > + if (rc > 0) > + rc = -EIO; > return rc; > } No: same problem. If we're successful rc is set to total (a positive integer) so as it falls through to fail: it's converted to -EIO which means we never return success. James