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 1A934C2C7 for ; Mon, 11 Sep 2023 09:50:57 +0000 (UTC) Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DF41ED; Mon, 11 Sep 2023 02:50:56 -0700 (PDT) Received: from canpemm500006.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4RkhhJ1BGZzNnL7; Mon, 11 Sep 2023 17:47:12 +0800 (CST) Received: from [10.174.179.200] (10.174.179.200) by canpemm500006.china.huawei.com (7.192.105.130) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Mon, 11 Sep 2023 17:50:54 +0800 Subject: Re: [PATCH net v3] team: fix null-ptr-deref when team device type is changed To: Hangbin Liu CC: , , , , , , References: <20230905081056.3365013-1-william.xuanziyang@huawei.com> From: "Ziyang Xuan (William)" Message-ID: <6cebaa19-bf09-173e-4f44-fae5f874895a@huawei.com> Date: Mon, 11 Sep 2023 17:50:53 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="gbk" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.179.200] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To canpemm500006.china.huawei.com (7.192.105.130) X-CFilter-Loop: Reflected X-Spam-Status: No, score=-3.4 required=5.0 tests=BAYES_00,NICE_REPLY_A, RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H5,RCVD_IN_MSPIKE_WL, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net > Hi Ziyang, > > You patch status is Changes Requested[1]. I think you need to repost this > patch. > > [1] https://patchwork.kernel.org/project/netdevbpf/patch/20230905081056.3365013-1-william.xuanziyang@huawei.com/ > Thanks for reminding. Patch v4 is sent. > Thanks > Hangbin > On Tue, Sep 05, 2023 at 04:10:56PM +0800, Ziyang Xuan wrote: >> Get a null-ptr-deref bug as follows with reproducer [1]. >> >> BUG: kernel NULL pointer dereference, address: 0000000000000228 >> ... >> RIP: 0010:vlan_dev_hard_header+0x35/0x140 [8021q] >> ... >> Call Trace: >> >> ? __die+0x24/0x70 >> ? page_fault_oops+0x82/0x150 >> ? exc_page_fault+0x69/0x150 >> ? asm_exc_page_fault+0x26/0x30 >> ? vlan_dev_hard_header+0x35/0x140 [8021q] >> ? vlan_dev_hard_header+0x8e/0x140 [8021q] >> neigh_connected_output+0xb2/0x100 >> ip6_finish_output2+0x1cb/0x520 >> ? nf_hook_slow+0x43/0xc0 >> ? ip6_mtu+0x46/0x80 >> ip6_finish_output+0x2a/0xb0 >> mld_sendpack+0x18f/0x250 >> mld_ifc_work+0x39/0x160 >> process_one_work+0x1e6/0x3f0 >> worker_thread+0x4d/0x2f0 >> ? __pfx_worker_thread+0x10/0x10 >> kthread+0xe5/0x120 >> ? __pfx_kthread+0x10/0x10 >> ret_from_fork+0x34/0x50 >> ? __pfx_kthread+0x10/0x10 >> ret_from_fork_asm+0x1b/0x30 >> >> [1] >> $ teamd -t team0 -d -c '{"runner": {"name": "loadbalance"}}' >> $ ip link add name t-dummy type dummy >> $ ip link add link t-dummy name t-dummy.100 type vlan id 100 >> $ ip link add name t-nlmon type nlmon >> $ ip link set t-nlmon master team0 >> $ ip link set t-nlmon nomaster >> $ ip link set t-dummy up >> $ ip link set team0 up >> $ ip link set t-dummy.100 down >> $ ip link set t-dummy.100 master team0 >> >> When enslave a vlan device to team device and team device type is changed >> from non-ether to ether, header_ops of team device is changed to >> vlan_header_ops. That is incorrect and will trigger null-ptr-deref >> for vlan->real_dev in vlan_dev_hard_header() because team device is not >> a vlan device. >> >> Assign eth_header_ops to header_ops of team device when its type is changed >> from non-ether to ether to fix the bug. >> >> Fixes: 1d76efe1577b ("team: add support for non-ethernet devices") >> Suggested-by: Hangbin Liu >> Signed-off-by: Ziyang Xuan >> --- >> v3: >> - Export eth_header_ops to fix modpost error. >> v2: >> - Just modify header_ops to eth_header_ops not use ether_setup(). >> --- >> drivers/net/team/team.c | 5 ++++- >> net/ethernet/eth.c | 1 + >> 2 files changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c >> index d3dc22509ea5..12fb5f4cff06 100644 >> --- a/drivers/net/team/team.c >> +++ b/drivers/net/team/team.c >> @@ -2127,7 +2127,10 @@ static const struct ethtool_ops team_ethtool_ops = { >> static void team_setup_by_port(struct net_device *dev, >> struct net_device *port_dev) >> { >> - dev->header_ops = port_dev->header_ops; >> + if (port_dev->type == ARPHRD_ETHER) >> + dev->header_ops = ð_header_ops; >> + else >> + dev->header_ops = port_dev->header_ops; >> dev->type = port_dev->type; >> dev->hard_header_len = port_dev->hard_header_len; >> dev->needed_headroom = port_dev->needed_headroom; >> diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c >> index 2edc8b796a4e..157833509adb 100644 >> --- a/net/ethernet/eth.c >> +++ b/net/ethernet/eth.c >> @@ -347,6 +347,7 @@ const struct header_ops eth_header_ops ____cacheline_aligned = { >> .cache_update = eth_header_cache_update, >> .parse_protocol = eth_header_parse_protocol, >> }; >> +EXPORT_SYMBOL(eth_header_ops); >> >> /** >> * ether_setup - setup Ethernet network device >> -- >> 2.25.1 >> > > . >