From patchwork Tue Jan 10 14:18:17 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Berger X-Patchwork-Id: 9507601 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 454366075F for ; Tue, 10 Jan 2017 14:18:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 383A82856B for ; Tue, 10 Jan 2017 14:18:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2D4EC28573; Tue, 10 Jan 2017 14:18:57 +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=-6.9 required=2.0 tests=BAYES_00,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 C3F892856F for ; Tue, 10 Jan 2017 14:18:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1033168AbdAJOSw (ORCPT ); Tue, 10 Jan 2017 09:18:52 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:45217 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1033097AbdAJOSt (ORCPT ); Tue, 10 Jan 2017 09:18:49 -0500 Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id v0AEEHG0078816 for ; Tue, 10 Jan 2017 09:18:48 -0500 Received: from e36.co.us.ibm.com (e36.co.us.ibm.com [32.97.110.154]) by mx0a-001b2d01.pphosted.com with ESMTP id 27vw1b37w9-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 10 Jan 2017 09:18:48 -0500 Received: from localhost by e36.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 10 Jan 2017 07:18:45 -0700 Received: from b03cxnp08025.gho.boulder.ibm.com (b03cxnp08025.gho.boulder.ibm.com [9.17.130.17]) by d03dlp01.boulder.ibm.com (Postfix) with ESMTP id 7661F1FF001F; Tue, 10 Jan 2017 07:18:23 -0700 (MST) Received: from b03ledav003.gho.boulder.ibm.com (b03ledav003.gho.boulder.ibm.com [9.17.130.234]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v0AEIirJ12058956; Tue, 10 Jan 2017 07:18:44 -0700 Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8E14A6A03F; Tue, 10 Jan 2017 07:18:44 -0700 (MST) Received: from sbct-3.watson.ibm.com (unknown [9.2.141.158]) by b03ledav003.gho.boulder.ibm.com (Postfix) with ESMTP id 309B96A03C; Tue, 10 Jan 2017 07:18:44 -0700 (MST) From: Stefan Berger To: tpmdd-devel@lists.sourceforge.net Cc: linux-security-module@vger.kernel.org, jarkko.sakkinen@linux.intel.com, Stefan Berger Subject: [PATCH 07/10] tpm: tpm2_unseal_cmd: check size of response before accessing data Date: Tue, 10 Jan 2017 09:18:17 -0500 X-Mailer: git-send-email 2.5.5 In-Reply-To: <1484057900-17871-1-git-send-email-stefanb@linux.vnet.ibm.com> References: <1484057900-17871-1-git-send-email-stefanb@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 17011014-0020-0000-0000-00000AB1905F X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00006408; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000199; SDB=6.00805683; UDB=6.00391989; IPR=6.00583019; BA=6.00005042; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00013877; XFM=3.00000011; UTC=2017-01-10 14:18:46 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17011014-0021-0000-0000-000058BE13A4 Message-Id: <1484057900-17871-7-git-send-email-stefanb@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-01-10_12:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1612050000 definitions=main-1701100209 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Check the size of the response before accessing data in the response packet. This is to avoid accessing data beyond the end of the response. Signed-off-by: Stefan Berger --- drivers/char/tpm/tpm2-cmd.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 4bcda2b..f55e876 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -689,6 +689,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, u16 data_len; u8 *data; int rc; + u32 rlength; rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL); if (rc) @@ -708,8 +709,19 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, rc = -EPERM; if (!rc) { + rlength = be32_to_cpu(((struct tpm2_cmd *)&buf) + ->header.out.length); + if (rlength < TPM_HEADER_SIZE + 4 + 2) { + rc = -EFAULT; + goto out; + } data_len = be16_to_cpup( (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]); + + if (rlength < TPM_HEADER_SIZE + 4 + 2 + data_len) { + rc = -EFAULT; + goto out; + } data = &buf.data[TPM_HEADER_SIZE + 6]; memcpy(payload->key, data, data_len - 1); @@ -717,6 +729,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, payload->migratable = data[data_len - 1]; } +out: tpm_buf_destroy(&buf); return rc; }