From patchwork Mon Dec 31 18:27:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Bottomley X-Patchwork-Id: 10745527 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ADF2013AD for ; Mon, 31 Dec 2018 18:27:35 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 92185289E1 for ; Mon, 31 Dec 2018 18:27:35 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 855AC28A05; Mon, 31 Dec 2018 18:27:35 +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=-7.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI 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 0B91B289E1 for ; Mon, 31 Dec 2018 18:27:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727415AbeLaS1e (ORCPT ); Mon, 31 Dec 2018 13:27:34 -0500 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:32822 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727379AbeLaS1e (ORCPT ); Mon, 31 Dec 2018 13:27:34 -0500 Received: from localhost (localhost [127.0.0.1]) by bedivere.hansenpartnership.com (Postfix) with ESMTP id D28038EE268; Mon, 31 Dec 2018 10:27:33 -0800 (PST) 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 f0XmpKzU0isl; Mon, 31 Dec 2018 10:27:33 -0800 (PST) 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 646648EE0BF; Mon, 31 Dec 2018 10:27:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=hansenpartnership.com; s=20151216; t=1546280853; bh=vBYbS4pIWfRNEvdYc9e3pAMU1EV1acIneM8ueTM7f3E=; h=Subject:From:To:Cc:Date:From; b=d2ay6yMrkcqxzylomu0rqxhtdStiDDGKtHChGiak11uCPoCHE65azTtFSEdghs1IB i+np48WBUrgqkfzc+wXb6yDAmlUbsuckS8N7Rste3Fgv4jPg80zUFP1dR5YiDHxEEy Wx+DN+fUg4HhH8ubR2EIKjnmUr4VbH7ysyQ3xlVY= Message-ID: <1546280851.3079.2.camel@HansenPartnership.com> Subject: [PATCH] tpm: fix incorrect success returns from tpm_try_transmit() From: James Bottomley To: Jarkko Sakkinen , Tomas Winkler Cc: linux-integrity@vger.kernel.org Date: Mon, 31 Dec 2018 10:27:31 -0800 X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 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 Ever since 627448e85c766 "tpm: separate cmd_ready/go_idle from runtime_pm" we have been returning success from tpm_try_transmit() even if an error occurred. The reason is that the introduction of rc = tpm_go_idle() at the end of processing overwrites the value of rc if it contains an error code (mostly with success). Fix this by writing the return to a new variable rc1 instead. Fixes: 627448e85c766 "tpm: separate cmd_ready/go_idle from runtime_pm" Cc: stable@vger.kernel.org Signed-off-by: James Bottomley --- Note: the goto out looks fishy as well. The only go_idle implementor is tpm_crb and that can return a timeout as -ETIME, so it looks like it would then loop forever diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 129f640424b7..ac7ebab6140c 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -432,7 +432,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, unsigned int flags) { struct tpm_output_header *header = (void *)buf; - int rc; + int rc, rc1; ssize_t len = 0; u32 count, ordinal; unsigned long stop; @@ -547,8 +547,8 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, dev_err(&chip->dev, "tpm2_commit_space: error %d\n", rc); out: - rc = tpm_go_idle(chip, flags); - if (rc) + rc1 = tpm_go_idle(chip, flags); + if (rc1) goto out; if (need_locality)