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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 25326C43441 for ; Tue, 27 Nov 2018 07:02:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B2478208E4 for ; Tue, 27 Nov 2018 07:02:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="El22LD7o" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B2478208E4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=163.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728961AbeK0R7P (ORCPT ); Tue, 27 Nov 2018 12:59:15 -0500 Received: from m12-12.163.com ([220.181.12.12]:60153 "EHLO m12-12.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728597AbeK0R7P (ORCPT ); Tue, 27 Nov 2018 12:59:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=n4qcQHCUeLmjnPnVLj h/wKr5FAa6bQ0ff11NUi0uUiw=; b=El22LD7oU3p2nJ0h7Y8voiZOxZJlw9au4c 5BlumJGD3bWLvMuQwA6Jn3mxtmnZmmnA7ULGCN0YxETZTcN6ncisNoogC9Co+acT +gn4LLIvE4co9GoR1idff7sNn/qz5lu1SHgYZAIdSzl0e215JeD6X4Ra6Gm4JD66 Z6wyfLsqI= Received: from bp.localdomain (unknown [106.120.213.96]) by smtp8 (Coremail) with SMTP id DMCowAB3uzHv6_xbhguxCA--.15263S3; Tue, 27 Nov 2018 15:02:09 +0800 (CST) From: Pan Bian To: Ilya Dryomov , "Yan, Zheng" , Sage Weil , "David S. Miller" Cc: ceph-devel@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Pan Bian Subject: [PATCH] libceph: fix use after free Date: Tue, 27 Nov 2018 15:02:07 +0800 Message-Id: <1543302127-14435-1-git-send-email-bianpan2016@163.com> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: DMCowAB3uzHv6_xbhguxCA--.15263S3 X-Coremail-Antispam: 1Uf129KBjvdXoWrKr4DCFy5XFy7XF45GFWfKrg_yoWDJrX_Za yjvr92ga1IyFWFk3ZFkws8AF4Igw1ruF1fGr1fCrW8A34UJFZxArs2v3s5ZF1fWF4UC3W7 XF4q9ry5Jr4xZjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IUnO6pDUUUUU== X-Originating-IP: [106.120.213.96] X-CM-SenderInfo: held01tdqsiiqw6rljoofrz/1tbiDhEMclXlpnhhiAAAsm Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The function ceph_monc_handle_map calls kfree(old) to free the old monitor map, old points to monc->monmap. However, after that, it reads monc->monmap->epoch and passes it to __ceph_monc_got_map. This result in a use-after-free bug. The patch moves the free operation after the call to __ceph_monc_got_map. Fixes: 82dcabad750("libceph: revamp subs code, switch to SUBSCRIBE2 protocol") Signed-off-by: Pan Bian --- net/ceph/mon_client.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ceph/mon_client.c b/net/ceph/mon_client.c index 18deb3d..05ef5aa 100644 --- a/net/ceph/mon_client.c +++ b/net/ceph/mon_client.c @@ -478,9 +478,10 @@ static void ceph_monc_handle_map(struct ceph_mon_client *monc, } client->monc.monmap = monmap; - kfree(old); __ceph_monc_got_map(monc, CEPH_SUB_MONMAP, monc->monmap->epoch); + kfree(old); + client->have_fsid = true; out: -- 2.7.4