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, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 387A8C43461 for ; Thu, 15 Apr 2021 14:54:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1E0A0613FB for ; Thu, 15 Apr 2021 14:54:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233778AbhDOOyp (ORCPT ); Thu, 15 Apr 2021 10:54:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:39798 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234166AbhDOOv5 (ORCPT ); Thu, 15 Apr 2021 10:51:57 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7783360FDC; Thu, 15 Apr 2021 14:51:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1618498293; bh=xhkDpRFRfP5r+hTYDvg5s+DyIrSAUNmXl65UQahiBLU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LfT8LHMoQ7tF1yKUln0BEwenkTnLvMCuxAzEakTs6nLk/4GpCrAVu9GDR09zEq6k2 sJRQnPJKe7nPDrPz0rVAEEXc+k4X/NQKN0yvfA/HFyHCjacBd6n1+un9HtS6pyqcrc tWu/q8ezWqdKHcxIRp9aEYe9ijs4QSk9eqCXsxD0= 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 4.9 08/47] nfc: Avoid endless loops caused by repeated llcp_sock_connect() Date: Thu, 15 Apr 2021 16:47:00 +0200 Message-Id: <20210415144413.747208914@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210415144413.487943796@linuxfoundation.org> References: <20210415144413.487943796@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 @@ -685,6 +685,10 @@ 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) {