From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8C8D11F95D for ; Fri, 21 Jul 2023 17:52:00 +0000 (UTC) Received: from mail-ej1-f54.google.com (mail-ej1-f54.google.com [209.85.218.54]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2A30635B3 for ; Fri, 21 Jul 2023 10:51:56 -0700 (PDT) Received: by mail-ej1-f54.google.com with SMTP id a640c23a62f3a-9928abc11deso339920266b.1 for ; Fri, 21 Jul 2023 10:51:56 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689961914; x=1690566714; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=frEdms5HYbKWvE7jkMnHGSIO92fXsFYBjlqmZl6Wyo4=; b=RNkqx+b8avEIvMpkaAuKDT60fqybpNACbJqZHarXXTnNUM13SqWfAyQxJmGx9Rdkhg 3E4tQ9GToFF3hX3950b0FrUmgPmM7AF7QcIfDuiH0FkmeoOH/qcTPL6eTluHJpghKbki TL8bWcfT/lW1YryMUbHnekFCiLeoFT7tsfYqaiXrhoL+WDRQrL6L20o4MIBNMO8EMeVJ nT30lpmhUFlL2KFIFQd/mSjVt/k4TbFLn6END3vHNpPmRCcBTyIOqW8qExcfN5j0gKb1 zKCjGf600XuDBEB1kW/Ikh22MENyEYFKiQuvCaZXho9urBEPfUiyV01rV2/MMFnFk6xe C7Bw== X-Gm-Message-State: ABy/qLbMNY9fEvkohgJcqWkVSkc8jQAP58ZEF4lXtHXqctx2l0Lz+Gm5 v5Yx37iNw7XrkMAKEIal/ZMIQWQ+5/UN1AJNcsX14MGq X-Google-Smtp-Source: APBJJlEsHGb0aT+5HeHhKudgXlsu7zv83ut4WTjlLfkSjHBuUawno53l7uhF4qlI8yMvFlVF1EZsog== X-Received: by 2002:a17:906:778e:b0:994:3395:942f with SMTP id s14-20020a170906778e00b009943395942fmr2348646ejm.17.1689961914717; Fri, 21 Jul 2023 10:51:54 -0700 (PDT) Received: from localhost.members.linode.com ([2a01:7e01::f03c:93ff:fead:d776]) by smtp.gmail.com with ESMTPSA id oy11-20020a170907104b00b0098822e05539sm2460669ejb.191.2023.07.21.10.51.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Jul 2023 10:51:54 -0700 (PDT) From: valis To: netdev@vger.kernel.org Cc: jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, pctammela@mojatatu.com, victor@mojatatu.com, ramdhan@starlabs.sg, billy@starlabs.sg Subject: [PATCH net 3/3] net/sched: cls_route: No longer copy tcf_result on update to avoid use-after-free Date: Fri, 21 Jul 2023 17:48:56 +0000 Message-Id: <20230721174856.3045-4-sec@valis.email> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230721174856.3045-1-sec@valis.email> References: <20230721174856.3045-1-sec@valis.email> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=1.4 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_BLOCKED, RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL,RCVD_IN_SBL_CSS,SPF_HELO_NONE, SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Level: * X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free. Fix this by no longer copying the tcf_result struct from the old filter. Fixes: 1109c00547fc ("net: sched: RCU cls_route") Reported-by: valis Reported-by: Bing-Jhong Billy Jheng Signed-off-by: valis Cc: stable@vger.kernel.org --- net/sched/cls_route.c | 1 - 1 file changed, 1 deletion(-) diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c index d0c53724d3e8..1e20bbd687f1 100644 --- a/net/sched/cls_route.c +++ b/net/sched/cls_route.c @@ -513,7 +513,6 @@ static int route4_change(struct net *net, struct sk_buff *in_skb, if (fold) { f->id = fold->id; f->iif = fold->iif; - f->res = fold->res; f->handle = fold->handle; f->tp = fold->tp; -- 2.30.2