From patchwork Fri Sep 17 08:07:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiasheng Jiang X-Patchwork-Id: 12501367 X-Patchwork-Delegate: kuba@kernel.org 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=-16.7 required=3.0 tests=BAYES_00, 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 E0657C433EF for ; Fri, 17 Sep 2021 08:08:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C887B61261 for ; Fri, 17 Sep 2021 08:08:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245258AbhIQIJb (ORCPT ); Fri, 17 Sep 2021 04:09:31 -0400 Received: from smtp25.cstnet.cn ([159.226.251.25]:49028 "EHLO cstnet.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S245122AbhIQIJZ (ORCPT ); Fri, 17 Sep 2021 04:09:25 -0400 Received: from localhost.localdomain (unknown [124.16.138.128]) by APP-05 (Coremail) with SMTP id zQCowADn7KyzTERhVJzRAA--.3914S2; Fri, 17 Sep 2021 16:07:16 +0800 (CST) From: Jiasheng Jiang To: pshelar@ovn.org, davem@davemloft.net, kuba@kernel.org Cc: netdev@vger.kernel.org, dev@openvswitch.org, linux-kernel@vger.kernel.org, Jiasheng Jiang Subject: [PATCH v2] openvswitch: Fix condition check in do_execute_actions() by using nla_ok() Date: Fri, 17 Sep 2021 08:07:14 +0000 Message-Id: <1631866034-3869133-1-git-send-email-jiasheng@iscas.ac.cn> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: zQCowADn7KyzTERhVJzRAA--.3914S2 X-Coremail-Antispam: 1UD129KBjvdXoWrtr13GrW5uF1xWw48WFW5trb_yoWkXFcEkw s3KF1kXw42yrn5Kr48KwsYqw1vvr13Gr1F9wn8KFWay3sYqws8uws8GrZ3Jr18ur429F98 Xw43Ar4Yga13ujkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbc8FF20E14v26r4j6ryUM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8w A2z4x0Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr0_ Cr1l84ACjcxK6I8E87Iv67AKxVWxJr0_GcWl84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s 0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xII jxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr 1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7MxkIecxEwVAFwVW8ZwCF 04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r 18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_JF0_Jw1lIxkGc2Ij64vI r41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Jr0_Gr 1lIxAIcVCF04k26cxKx2IYs7xG6rW3Jr0E3s1lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAI cVC2z280aVCY1x0267AKxVWUJVW8JbIYCTnIWIevJa73UjIFyTuYvjfUeHUDDUUUU X-Originating-IP: [124.16.138.128] X-CM-SenderInfo: pmld2xxhqjqxpvfd2hldfou0/ Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Just using 'rem > 0' might be unsafe, so it's better to use the nla_ok() instead. Because we can see from the nla_next() that '*remaining' might be smaller than 'totlen'. And nla_ok() will avoid it happening. For example, ovs_dp_process_packet() -> ovs_execute_actions() -> do_execute_actions(), and attr comes from OVS_CB(skb)->input_vport, which restores the received packet from the user space. Fixes: ccb1352e76cff0524e7ccb2074826a092dd13016 ('net: Add Open vSwitch kernel components.') Signed-off-by: Jiasheng Jiang --- net/openvswitch/actions.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c index 77d924a..c23537f 100644 --- a/net/openvswitch/actions.c +++ b/net/openvswitch/actions.c @@ -1238,8 +1238,7 @@ static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, const struct nlattr *a; int rem; - for (a = attr, rem = len; rem > 0; - a = nla_next(a, &rem)) { + nla_for_each_attr(a, attr, len, rem) { int err = 0; switch (nla_type(a)) {