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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 650B3C43142 for ; Wed, 3 Mar 2021 12:56:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 17DFF64E58 for ; Wed, 3 Mar 2021 12:56:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1358513AbhCCMGn (ORCPT ); Wed, 3 Mar 2021 07:06:43 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:12676 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1355015AbhCCGR5 (ORCPT ); Wed, 3 Mar 2021 01:17:57 -0500 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4Dr3cx5qBWzlRg3; Wed, 3 Mar 2021 14:14:57 +0800 (CST) Received: from use12-sp2.huawei.com (10.67.189.174) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.498.0; Wed, 3 Mar 2021 14:16:57 +0800 From: Xiaoming Ni To: , , , , , , , , , , , CC: , , Subject: [PATCH 1/4] nfc: fix refcount leak in llcp_sock_bind() Date: Wed, 3 Mar 2021 14:16:51 +0800 Message-ID: <20210303061654.127666-2-nixiaoming@huawei.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210303061654.127666-1-nixiaoming@huawei.com> References: <20210303061654.127666-1-nixiaoming@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.67.189.174] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org nfc_llcp_local_get() is invoked in llcp_sock_bind(), but nfc_llcp_local_put() is not invoked in subsequent failure branches. As a result, refcount leakage occurs. To fix it, add calling nfc_llcp_local_put(). fix CVE-2020-25670 Fixes: c7aa12252f51 ("NFC: Take a reference on the LLCP local pointer when creating a socket") Reported-by: "kiyin(尹亮)" Link: https://www.openwall.com/lists/oss-security/2020/11/01/1 Cc: #v3.6 Signed-off-by: Xiaoming Ni --- net/nfc/llcp_sock.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/nfc/llcp_sock.c b/net/nfc/llcp_sock.c index d257ed3b732a..68832ee4b9f8 100644 --- a/net/nfc/llcp_sock.c +++ b/net/nfc/llcp_sock.c @@ -108,11 +108,13 @@ static int llcp_sock_bind(struct socket *sock, struct sockaddr *addr, int alen) llcp_sock->service_name_len, GFP_KERNEL); if (!llcp_sock->service_name) { + nfc_llcp_local_put(llcp_sock->local); ret = -ENOMEM; goto put_dev; } llcp_sock->ssap = nfc_llcp_get_sdp_ssap(local, llcp_sock); if (llcp_sock->ssap == LLCP_SAP_MAX) { + nfc_llcp_local_put(llcp_sock->local); kfree(llcp_sock->service_name); llcp_sock->service_name = NULL; ret = -EADDRINUSE; -- 2.27.0