From patchwork Wed Jun 8 14:35:37 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jianglei Nie X-Patchwork-Id: 12873592 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 905C9C433EF for ; Wed, 8 Jun 2022 14:36:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241465AbiFHOg1 (ORCPT ); Wed, 8 Jun 2022 10:36:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33176 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241005AbiFHOgZ (ORCPT ); Wed, 8 Jun 2022 10:36:25 -0400 Received: from mail-m973.mail.163.com (mail-m973.mail.163.com [123.126.97.3]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id CB4235D657; Wed, 8 Jun 2022 07:36:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id:MIME-Version; bh=hNRcY edXWJStsYzsJqJCSjMPXwEroJLu2AmA8UpFdZI=; b=aqW+LtPQRrRZLwEo6zwRR jfZhnIL5iSBlDM8VmdwxX8ZPkPI/38wuPKAvZOkvFv3kGSxRiQH8XYD9Dd8VvezC xGduaKQmylfhieA7+XI4HWYlO0Dvq5juO1mFnark3GofRwDdAZrkjmTImYN2HjIx +wXyWsOlIy2K0/SzsQ9In0= Received: from localhost.localdomain (unknown [123.112.69.106]) by smtp3 (Coremail) with SMTP id G9xpCgCHZF29s6BiAhfvHg--.26185S4; Wed, 08 Jun 2022 22:35:49 +0800 (CST) From: Jianglei Nie To: jejb@linux.ibm.com, jarkko@kernel.org, zohar@linux.ibm.com, dhowells@redhat.com, jmorris@namei.org, serge@hallyn.com Cc: linux-integrity@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, Jianglei Nie Subject: [PATCH v2] KEYS: trusted: Fix memory leak in tpm2_key_encode() Date: Wed, 8 Jun 2022 22:35:37 +0800 Message-Id: <20220608143537.670675-1-niejianglei2021@163.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-CM-TRANSID: G9xpCgCHZF29s6BiAhfvHg--.26185S4 X-Coremail-Antispam: 1Uf129KBjvJXoW7urWxGF17XFWDJrWkCFy7trb_yoW8KF47pF ZxKF13XrW29ry3Ary3JF4SvFWSkw1rGF42gws2g397GasxJFsrKFy2yr4Ygr13AFWFgw15 ZFWDZFWUuFWqqr7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0zRID7fUUUUU= X-Originating-IP: [123.112.69.106] X-CM-SenderInfo: xqlhyxxdqjzvrlsqjii6rwjhhfrp/1tbiFQUajF5mLINbvQAAs3 Precedence: bulk List-ID: X-Mailing-List: keyrings@vger.kernel.org tpm2_key_encode() allocates a memory chunk from scratch with kmalloc(), but it is never freed, which leads to a memory leak. Free the memory chunk with kfree() in the return path. Signed-off-by: Jianglei Nie --- security/keys/trusted-keys/trusted_tpm2.c | 24 +++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c index 0165da386289..6fd426212386 100644 --- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -32,6 +32,7 @@ static int tpm2_key_encode(struct trusted_key_payload *payload, struct trusted_key_options *options, u8 *src, u32 len) { + int err; const int SCRATCH_SIZE = PAGE_SIZE; u8 *scratch = kmalloc(SCRATCH_SIZE, GFP_KERNEL); u8 *work = scratch, *work1; @@ -57,8 +58,10 @@ static int tpm2_key_encode(struct trusted_key_payload *payload, unsigned char bool[3], *w = bool; /* tag 0 is emptyAuth */ w = asn1_encode_boolean(w, w + sizeof(bool), true); - if (WARN(IS_ERR(w), "BUG: Boolean failed to encode")) - return PTR_ERR(w); + if (WARN(IS_ERR(w), "BUG: Boolean failed to encode")) { + err = PTR_ERR(w); + goto out; + } work = asn1_encode_tag(work, end_work, 0, bool, w - bool); } @@ -69,8 +72,10 @@ static int tpm2_key_encode(struct trusted_key_payload *payload, * trigger, so if it does there's something nefarious going on */ if (WARN(work - scratch + pub_len + priv_len + 14 > SCRATCH_SIZE, - "BUG: scratch buffer is too small")) - return -EINVAL; + "BUG: scratch buffer is too small")) { + err = -EINVAL; + goto out; + } work = asn1_encode_integer(work, end_work, options->keyhandle); work = asn1_encode_octet_string(work, end_work, pub, pub_len); @@ -79,10 +84,17 @@ static int tpm2_key_encode(struct trusted_key_payload *payload, work1 = payload->blob; work1 = asn1_encode_sequence(work1, work1 + sizeof(payload->blob), scratch, work - scratch); - if (WARN(IS_ERR(work1), "BUG: ASN.1 encoder failed")) - return PTR_ERR(work1); + if (WARN(IS_ERR(work1), "BUG: ASN.1 encoder failed")) { + err = -EINVAL; + goto out; + } + kfree(scratch); return work1 - payload->blob; + +out: + kfree(scratch); + return err; } struct tpm2_key_context {