From patchwork Wed Jun 20 14:38:23 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ricardo Schwarzmeier X-Patchwork-Id: 10477673 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 7C87F60210 for ; Wed, 20 Jun 2018 14:52:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6ACC628EBB for ; Wed, 20 Jun 2018 14:52:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5F11828ED6; Wed, 20 Jun 2018 14:52:33 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4F11628EBB for ; Wed, 20 Jun 2018 14:52:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753202AbeFTOwb (ORCPT ); Wed, 20 Jun 2018 10:52:31 -0400 Received: from smtp11.infineon.com ([217.10.52.105]:11157 "EHLO smtp11.infineon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752932AbeFTOwa (ORCPT ); Wed, 20 Jun 2018 10:52:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=infineon.com; i=@infineon.com; q=dns/txt; s=IFXMAIL; t=1529506351; x=1561042351; h=from:to:cc:subject:date:message-id:mime-version; bh=3S1dhYYVfJB8qM1C1UJRLghjn9H9eCa5nmobLZWhglE=; b=UBC7+O3UxZ206c/SlTXJ9SUflCeN955f6PLLTqJJhrPk08Q87P+CDu5j GvekxHOGL+LWpG0a0i/kIeIuGeQQ+mqFXmjMDKcmGpEE37kPjp9rd/DH2 nCBojEX5P21uQMV0DduqT7h7K6e25hd1m/fWhV8J9N3xnMqpOsFfPFuoe o=; X-SBRS: None X-IronPort-AV: E=McAfee;i="5900,7806,8929"; a="82664088" X-IronPort-AV: E=Sophos;i="5.51,247,1526335200"; d="scan'208";a="82664088" Received: from unknown (HELO mucxv001.muc.infineon.com) ([172.23.11.16]) by smtp11.infineon.com with ESMTP/TLS/AES256-GCM-SHA384; 20 Jun 2018 16:52:30 +0200 Received: from MUCSE707.infineon.com (MUCSE707.infineon.com [172.23.7.81]) by mucxv001.muc.infineon.com (Postfix) with ESMTPS; Wed, 20 Jun 2018 16:52:29 +0200 (CEST) Received: from MUCSE716.infineon.com (172.23.7.67) by MUCSE707.infineon.com (172.23.7.81) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P256) id 15.1.1466.3; Wed, 20 Jun 2018 16:52:28 +0200 Received: from schwaric-VirtualBox.agb.infineon.com (172.23.8.247) by MUCSE716.infineon.com (172.23.7.67) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P256) id 15.1.1466.3; Wed, 20 Jun 2018 16:52:29 +0200 From: Ricardo Schwarzmeier To: CC: , , , , , , Ricardo Schwarzmeier Subject: [PATCH v3] tpm: Return the actual size when receiving an unsupported command Date: Wed, 20 Jun 2018 16:38:23 +0200 Message-ID: <20180620143823.14718-1-Ricardo.Schwarzmeier@infineon.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-Originating-IP: [172.23.8.247] X-ClientProxiedBy: MUCSE715.infineon.com (172.23.7.66) To MUCSE716.infineon.com (172.23.7.67) Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The userpace expects to read the number of bytes stated in the header. Returning the size of the buffer instead would be unexpected. Fixes: 095531f891e6 ("tpm: return a TPM_RC_COMMAND_CODE response if command is not implemented") Signed-off-by: Ricardo Schwarzmeier --- Changes since v2: * Made commit message more clear * Avoided endianness problems --- drivers/char/tpm/tpm-interface.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index e32f6e85dc6d..7f2e2d54894d 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -423,7 +423,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS); header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE | TSS2_RESMGR_TPM_RC_LAYER); - return bufsiz; + return sizeof(*header); } if (bufsiz > TPM_BUFSIZE)