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 3ACA1C43441 for ; Tue, 27 Nov 2018 09:21:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EB1F82086B for ; Tue, 27 Nov 2018 09:21:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="egnCOtzZ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EB1F82086B 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 S1730175AbeK0USx (ORCPT ); Tue, 27 Nov 2018 15:18:53 -0500 Received: from m12-15.163.com ([220.181.12.15]:34748 "EHLO m12-15.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729747AbeK0USx (ORCPT ); Tue, 27 Nov 2018 15:18:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=P7d7oRFMpZRZlDmpOo /WNtGhi4hsYq/yW6a+B3n9tDM=; b=egnCOtzZcjXz52iCk8VBMq08h1scOMjhsb tgX5ggP8iUCetDSdqT28o2zKHTjiNXJiC3xeySCSE0zYaT5O6wot7ep0jgC8IEPy q2sgLLadgRJd2PyP2kTEsvyAvh0AjJsjQn18EtiDhZoL8f2+geagZujILuukSACv thxiqr0dY= Received: from bp.localdomain (unknown [106.120.213.96]) by smtp11 (Coremail) with SMTP id D8CowACHjyyRDP1bJXitAA--.6645S3; Tue, 27 Nov 2018 17:21:24 +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 V2] libceph: fix use after free Date: Tue, 27 Nov 2018 17:21:12 +0800 Message-Id: <1543310472-31861-1-git-send-email-bianpan2016@163.com> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: D8CowACHjyyRDP1bJXitAA--.6645S3 X-Coremail-Antispam: 1Uf129KBjvdXoWrKr4DCFy5XFy7XF48tw1UKFg_yoWDArg_Za yUZryvgw1SyFWFk3ZFkws8AF4xWw18uF1fGr1fArW8A34UJrsxArs2v34rZF1xGF4UCw17 XF4Dury5Jr1xZjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IU0qXdUUUUUU== X-Originating-IP: [106.120.213.96] X-CM-SenderInfo: held01tdqsiiqw6rljoofrz/xtbBzxQMclaD0boqxAAAs1 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 will 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 --- V2: correct the format of the tag Fixes --- 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