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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07E02C433EF for ; Mon, 25 Oct 2021 03:25:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D76BC61029 for ; Mon, 25 Oct 2021 03:25:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232008AbhJYD10 (ORCPT ); Sun, 24 Oct 2021 23:27:26 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:25311 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232072AbhJYD1Z (ORCPT ); Sun, 24 Oct 2021 23:27:25 -0400 Received: from dggeml757-chm.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Hd0Zb6RcRzbhFj; Mon, 25 Oct 2021 11:20:23 +0800 (CST) Received: from localhost.localdomain (10.175.104.82) by dggeml757-chm.china.huawei.com (10.1.199.137) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.15; Mon, 25 Oct 2021 11:25:00 +0800 From: Ziyang Xuan To: , CC: , , , , , Subject: [PATCH rdma-rc] IB/core: fix a UAF for netdev in netdevice_event process Date: Mon, 25 Oct 2021 11:42:58 +0800 Message-ID: <20211025034258.2426872-1-william.xuanziyang@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.104.82] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggeml757-chm.china.huawei.com (10.1.199.137) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org When a vlan netdev enter netdevice_event process although it is not a roce netdev, it will be passed to netdevice_event_work_handler() to process. In order to hold the netdev of netdevice_event after netdevice_event() return, call dev_hold() to hold the netdev in netdevice_queue_work(). But that did not consider the real_dev of a vlan netdev, the real_dev can be freed within netdevice_event_work_handler() be scheduled. It would trigger the UAF problem for the real_dev like following: ================================================================== BUG: KASAN: use-after-free in vlan_dev_real_dev+0xf9/0x120 Read of size 4 at addr ffff88801648a0c4 by task kworker/u8:0/8 Workqueue: gid-cache-wq netdevice_event_work_handler Call Trace: dump_stack_lvl+0xcd/0x134 print_address_description.constprop.0.cold+0x93/0x334 kasan_report.cold+0x83/0xdf vlan_dev_real_dev+0xf9/0x120 is_eth_port_of_netdev_filter.part.0+0xb1/0x2c0 is_eth_port_of_netdev_filter+0x28/0x40 ib_enum_roce_netdev+0x1a3/0x300 ib_enum_all_roce_netdevs+0xc7/0x140 netdevice_event_work_handler+0x9d/0x210 ... Allocated by task 9289: kasan_save_stack+0x1b/0x40 __kasan_kmalloc+0x9b/0xd0 __kmalloc_node+0x20a/0x330 kvmalloc_node+0x61/0xf0 alloc_netdev_mqs+0x9d/0x1140 rtnl_create_link+0x955/0xb70 __rtnl_newlink+0xe10/0x15b0 rtnl_newlink+0x64/0xa0 ... Freed by task 9288: kasan_save_stack+0x1b/0x40 kasan_set_track+0x1c/0x30 kasan_set_free_info+0x20/0x30 __kasan_slab_free+0xfc/0x130 slab_free_freelist_hook+0xdd/0x240 kfree+0xe4/0x690 kvfree+0x42/0x50 device_release+0x9f/0x240 kobject_put+0x1c8/0x530 put_device+0x1b/0x30 free_netdev+0x370/0x540 ppp_destroy_interface+0x313/0x3d0 ppp_release+0x1bf/0x240 ... Hold the real_dev for a vlan netdev in netdevice_event_work_handler() to fix the UAF problem. Fixes: 238fdf48f2b5 ("IB/core: Add RoCE table bonding support") Reported-by: syzbot+e4df4e1389e28972e955@syzkaller.appspotmail.com Signed-off-by: Ziyang Xuan --- drivers/infiniband/core/roce_gid_mgmt.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/core/roce_gid_mgmt.c b/drivers/infiniband/core/roce_gid_mgmt.c index 68197e576433..063dbe72b7c2 100644 --- a/drivers/infiniband/core/roce_gid_mgmt.c +++ b/drivers/infiniband/core/roce_gid_mgmt.c @@ -621,6 +621,7 @@ static void netdevice_event_work_handler(struct work_struct *_work) { struct netdev_event_work *work = container_of(_work, struct netdev_event_work, work); + struct net_device *real_dev; unsigned int i; for (i = 0; i < ARRAY_SIZE(work->cmds) && work->cmds[i].cb; i++) { @@ -628,6 +629,12 @@ static void netdevice_event_work_handler(struct work_struct *_work) work->cmds[i].filter_ndev, work->cmds[i].cb, work->cmds[i].ndev); + real_dev = rdma_vlan_dev_real_dev(work->cmds[i].ndev); + if (real_dev) + dev_put(real_dev); + real_dev = rdma_vlan_dev_real_dev(work->cmds[i].filter_ndev); + if (real_dev) + dev_put(real_dev); dev_put(work->cmds[i].ndev); dev_put(work->cmds[i].filter_ndev); } @@ -638,9 +645,10 @@ static void netdevice_event_work_handler(struct work_struct *_work) static int netdevice_queue_work(struct netdev_event_work_cmd *cmds, struct net_device *ndev) { - unsigned int i; struct netdev_event_work *ndev_work = kmalloc(sizeof(*ndev_work), GFP_KERNEL); + struct net_device *real_dev; + unsigned int i; if (!ndev_work) return NOTIFY_DONE; @@ -653,6 +661,12 @@ static int netdevice_queue_work(struct netdev_event_work_cmd *cmds, ndev_work->cmds[i].filter_ndev = ndev; dev_hold(ndev_work->cmds[i].ndev); dev_hold(ndev_work->cmds[i].filter_ndev); + real_dev = rdma_vlan_dev_real_dev(ndev_work->cmds[i].ndev); + if (real_dev) + dev_hold(real_dev); + real_dev = rdma_vlan_dev_real_dev(ndev_work->cmds[i].filter_ndev); + if (real_dev) + dev_hold(real_dev); } INIT_WORK(&ndev_work->work, netdevice_event_work_handler); -- 2.25.1