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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 2F57FC433B4 for ; Mon, 12 Apr 2021 08:46:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EF21061287 for ; Mon, 12 Apr 2021 08:46:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237952AbhDLIqq (ORCPT ); Mon, 12 Apr 2021 04:46:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:38378 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237761AbhDLIp6 (ORCPT ); Mon, 12 Apr 2021 04:45:58 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 22B986124A; Mon, 12 Apr 2021 08:45:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1618217136; bh=hgbYQ5L79uypRxxIO2S3Vn64L3Vc1hz9tY8Q2ZyH1nA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hzEAvLpGn+GAEuk335ouB6eaUwn3BbDzJHQ4N0FoG5rbl6C9rFuIIXjcVawmk+MTh mgNLQxSBNbIWN7fm3g8DHNeCpCD7LbgyFmjtHY0kmhpxJ710Xdd1UgpLxpSkXFXR1d P+e+LFQI+U9d4r2RKxAgxknybv6LnSH/WTdt+KNc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?kiyin ?= , Xiaoming Ni , "David S. Miller" Subject: [PATCH 5.4 008/111] nfc: Avoid endless loops caused by repeated llcp_sock_connect() Date: Mon, 12 Apr 2021 10:39:46 +0200 Message-Id: <20210412084004.490597026@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210412084004.200986670@linuxfoundation.org> References: <20210412084004.200986670@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Xiaoming Ni commit 4b5db93e7f2afbdfe3b78e37879a85290187e6f1 upstream. When sock_wait_state() returns -EINPROGRESS, "sk->sk_state" is LLCP_CONNECTING. In this case, llcp_sock_connect() is repeatedly invoked, nfc_llcp_sock_link() will add sk to local->connecting_sockets twice. sk->sk_node->next will point to itself, that will make an endless loop and hang-up the system. To fix it, check whether sk->sk_state is LLCP_CONNECTING in llcp_sock_connect() to avoid repeated invoking. Fixes: b4011239a08e ("NFC: llcp: Fix non blocking sockets connections") Reported-by: "kiyin(尹亮)" Link: https://www.openwall.com/lists/oss-security/2020/11/01/1 Cc: #v3.11 Signed-off-by: Xiaoming Ni Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/nfc/llcp_sock.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/net/nfc/llcp_sock.c +++ b/net/nfc/llcp_sock.c @@ -673,6 +673,10 @@ static int llcp_sock_connect(struct sock ret = -EISCONN; goto error; } + if (sk->sk_state == LLCP_CONNECTING) { + ret = -EINPROGRESS; + goto error; + } dev = nfc_get_device(addr->dev_idx); if (dev == NULL) {