From patchwork Mon Jul 3 11:08:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lin Ma X-Patchwork-Id: 13299974 X-Patchwork-Delegate: kuba@kernel.org 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 24773DDA5 for ; Mon, 3 Jul 2023 11:09:14 +0000 (UTC) Received: from azure-sdnproxy.icoremail.net (azure-sdnproxy.icoremail.net [52.237.72.81]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id AB780C4 for ; Mon, 3 Jul 2023 04:09:11 -0700 (PDT) Received: from localhost.localdomain (unknown [122.235.246.99]) by mail-app3 (Coremail) with SMTP id cC_KCgBXCJ07rKJk7DGtCQ--.10331S4; Mon, 03 Jul 2023 19:08:44 +0800 (CST) From: Lin Ma To: jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org Cc: Lin Ma Subject: [PATCH v1] net/sched: act_pedit: Add size check for TCA_PEDIT_PARMS_EX Date: Mon, 3 Jul 2023 19:08:42 +0800 Message-Id: <20230703110842.590282-1-linma@zju.edu.cn> X-Mailer: git-send-email 2.17.1 X-CM-TRANSID: cC_KCgBXCJ07rKJk7DGtCQ--.10331S4 X-Coremail-Antispam: 1UD129KBjvJXoW7ury3KrykZFyxAw45JF15XFb_yoW8Xr18pF yDWa97Kw47WFy3WF1SyFs7Za4Igw1rGr1UGr1qkr4fArn8Wa1rW3Wj9r97urZrCr4DZ347 Jr1UtrWfJ3Wvvr7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUym14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWUJV W8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I1l42xK82IYc2Ij64vI r41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8Gjc xK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0 cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r1j6r4UMIIF0xvE42xK8V AvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E 14v26r1j6r4UYxBIdaVFxhVjvjDU0xZFpf9x0JUdHUDUUUUU= X-CM-SenderInfo: qtrwiiyqvtljo62m3hxhgxhubq/ X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2,RCVD_IN_VALIDITY_RPBL,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: X-Patchwork-Delegate: kuba@kernel.org The attribute TCA_PEDIT_PARMS_EX is not be included in pedit_policy and one malicious user could fake a TCA_PEDIT_PARMS_EX whose length is smaller than the intended sizeof(struct tc_pedit). Hence, the dereference in tcf_pedit_init() could access dirty heap data. static int tcf_pedit_init(...) { // ... pattr = tb[TCA_PEDIT_PARMS]; // TCA_PEDIT_PARMS is included if (!pattr) pattr = tb[TCA_PEDIT_PARMS_EX]; // but this is not // ... parm = nla_data(pattr); index = parm->index; // parm is able to be smaller than 4 bytes // and this dereference gets dirty skb_buff // data created in netlink_sendmsg } This commit adds TCA_PEDIT_PARMS_EX length in pedit_policy which avoid the above case, just like the TCA_PEDIT_PARMS. Fixes: 71d0ed7079df ("net/act_pedit: Support using offset relative to the conventional network headers") Signed-off-by: Lin Ma Reviewed-by: Pedro Tammela --- net/sched/act_pedit.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c index b562fc2bb5b1..1ef8fcfa9997 100644 --- a/net/sched/act_pedit.c +++ b/net/sched/act_pedit.c @@ -29,6 +29,7 @@ static struct tc_action_ops act_pedit_ops; static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = { [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) }, + [TCA_PEDIT_PARMS_EX] = { .len = sizeof(struct tc_pedit) }, [TCA_PEDIT_KEYS_EX] = { .type = NLA_NESTED }, };