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,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=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 B7B13C4332E for ; Fri, 22 Jan 2021 18:44:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 868CD23B01 for ; Fri, 22 Jan 2021 18:44:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730010AbhAVSnV (ORCPT ); Fri, 22 Jan 2021 13:43:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:39306 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728521AbhAVOWG (ORCPT ); Fri, 22 Jan 2021 09:22:06 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id ADF8723B54; Fri, 22 Jan 2021 14:16:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1611324973; bh=pimP6n21U/JGJRQ910aCkQFtVX5QrplC560wCofPJnk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hYT3J4EfvpPGFA9Qpuk08wejxE0uqidb6UIrDfkeX+wacQw2S4smK+eO2gDbxPned g0ZJA2BuUrlF+M8OCh9x1z1qj4akI6BIhr+Ztt6cUVnCPELU2B0IScHyw5IIY7H70f 1CXbZtUOm+wdQtf9FgkU6uZcD2ruogpwCJnbzxDA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Baptiste Lepers , Willem de Bruijn , Jakub Kicinski Subject: [PATCH 4.19 06/22] udp: Prevent reuseport_select_sock from reading uninitialized socks Date: Fri, 22 Jan 2021 15:12:24 +0100 Message-Id: <20210122135732.172920223@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210122135731.921636245@linuxfoundation.org> References: <20210122135731.921636245@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: Baptiste Lepers [ Upstream commit fd2ddef043592e7de80af53f47fa46fd3573086e ] reuse->socks[] is modified concurrently by reuseport_add_sock. To prevent reading values that have not been fully initialized, only read the array up until the last known safe index instead of incorrectly re-reading the last index of the array. Fixes: acdcecc61285f ("udp: correct reuseport selection with connected sockets") Signed-off-by: Baptiste Lepers Acked-by: Willem de Bruijn Link: https://lore.kernel.org/r/20210107051110.12247-1-baptiste.lepers@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/core/sock_reuseport.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/core/sock_reuseport.c +++ b/net/core/sock_reuseport.c @@ -299,7 +299,7 @@ select_by_hash: i = j = reciprocal_scale(hash, socks); while (reuse->socks[i]->sk_state == TCP_ESTABLISHED) { i++; - if (i >= reuse->num_socks) + if (i >= socks) i = 0; if (i == j) goto out;