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 X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 A794EC43219 for ; Sat, 27 Apr 2019 15:19:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 77784206A3 for ; Sat, 27 Apr 2019 15:19:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728135AbfD0PTZ (ORCPT ); Sat, 27 Apr 2019 11:19:25 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:34128 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727661AbfD0PPh (ORCPT ); Sat, 27 Apr 2019 11:15:37 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hKP38-0000z8-35; Sat, 27 Apr 2019 16:15:34 +0100 Received: from ben by deadeye with local (Exim 4.92) (envelope-from ) id 1hKP2j-0004T5-Ez; Sat, 27 Apr 2019 16:15:09 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Leon Romanovsky" , "Jason Gunthorpe" , "Erez Shitrit" , "Feras Daoud" Date: Sat, 27 Apr 2019 16:13:09 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 068/202] IB/ipoib: Fix for use-after-free in ipoib_cm_tx_start In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.66-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Feras Daoud commit 6ab4aba00f811a5265acc4d3eb1863bb3ca60562 upstream. The following BUG was reported by kasan: BUG: KASAN: use-after-free in ipoib_cm_tx_start+0x430/0x1390 [ib_ipoib] Read of size 80 at addr ffff88034c30bcd0 by task kworker/u16:1/24020 Workqueue: ipoib_wq ipoib_cm_tx_start [ib_ipoib] Call Trace: dump_stack+0x9a/0xeb print_address_description+0xe3/0x2e0 kasan_report+0x18a/0x2e0 ? ipoib_cm_tx_start+0x430/0x1390 [ib_ipoib] memcpy+0x1f/0x50 ipoib_cm_tx_start+0x430/0x1390 [ib_ipoib] ? kvm_clock_read+0x1f/0x30 ? ipoib_cm_skb_reap+0x610/0x610 [ib_ipoib] ? __lock_is_held+0xc2/0x170 ? process_one_work+0x880/0x1960 ? process_one_work+0x912/0x1960 process_one_work+0x912/0x1960 ? wq_pool_ids_show+0x310/0x310 ? lock_acquire+0x145/0x440 worker_thread+0x87/0xbb0 ? process_one_work+0x1960/0x1960 kthread+0x314/0x3d0 ? kthread_create_worker_on_cpu+0xc0/0xc0 ret_from_fork+0x3a/0x50 Allocated by task 0: kasan_kmalloc+0xa0/0xd0 kmem_cache_alloc_trace+0x168/0x3e0 path_rec_create+0xa2/0x1f0 [ib_ipoib] ipoib_start_xmit+0xa98/0x19e0 [ib_ipoib] dev_hard_start_xmit+0x159/0x8d0 sch_direct_xmit+0x226/0xb40 __dev_queue_xmit+0x1d63/0x2950 neigh_update+0x889/0x1770 arp_process+0xc47/0x21f0 arp_rcv+0x462/0x760 __netif_receive_skb_core+0x1546/0x2da0 netif_receive_skb_internal+0xf2/0x590 napi_gro_receive+0x28e/0x390 ipoib_ib_handle_rx_wc_rss+0x873/0x1b60 [ib_ipoib] ipoib_rx_poll_rss+0x17d/0x320 [ib_ipoib] net_rx_action+0x427/0xe30 __do_softirq+0x28e/0xc42 Freed by task 26680: __kasan_slab_free+0x11d/0x160 kfree+0xf5/0x360 ipoib_flush_paths+0x532/0x9d0 [ib_ipoib] ipoib_set_mode_rss+0x1ad/0x560 [ib_ipoib] set_mode+0xc8/0x150 [ib_ipoib] kernfs_fop_write+0x279/0x440 __vfs_write+0xd8/0x5c0 vfs_write+0x15e/0x470 ksys_write+0xb8/0x180 do_syscall_64+0x9b/0x420 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88034c30bcc8 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 8 bytes inside of 512-byte region [ffff88034c30bcc8, ffff88034c30bec8) The buggy address belongs to the page: The following race between change mode and xmit flow is the reason for this use-after-free: Change mode Send packet 1 to GID XX Send packet 2 to GID XX | | | start | | | | | | | | | Create new path for GID XX | | and update neigh path | | | | | | | | | | flush_paths | | | | queue_work(cm.start_task) | | Path for GID XX not found | create new path | | start_task runs with old released path There is no locking to protect the lifetime of the path through the ipoib_cm_tx struct, so delete it entirely and always use the newly looked up path under the priv->lock. Fixes: 546481c2816e ("IB/ipoib: Fix memory corruption in ipoib cm mode connect flow") Signed-off-by: Feras Daoud Reviewed-by: Erez Shitrit Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- drivers/infiniband/ulp/ipoib/ipoib.h | 1 - drivers/infiniband/ulp/ipoib/ipoib_cm.c | 3 +-- 2 files changed, 1 insertion(+), 3 deletions(-) --- a/drivers/infiniband/ulp/ipoib/ipoib.h +++ b/drivers/infiniband/ulp/ipoib/ipoib.h @@ -228,7 +228,6 @@ struct ipoib_cm_tx { struct list_head list; struct net_device *dev; struct ipoib_neigh *neigh; - struct ipoib_path *path; struct ipoib_cm_tx_buf *tx_ring; unsigned tx_head; unsigned tx_tail; --- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c @@ -1279,7 +1279,6 @@ struct ipoib_cm_tx *ipoib_cm_create_tx(s neigh->cm = tx; tx->neigh = neigh; - tx->path = path; tx->dev = dev; list_add(&tx->list, &priv->cm.start_list); set_bit(IPOIB_FLAG_INITIALIZED, &tx->flags); @@ -1338,7 +1337,7 @@ static void ipoib_cm_tx_start(struct wor neigh->daddr + QPN_AND_OPTIONS_OFFSET); goto free_neigh; } - memcpy(&pathrec, &p->path->pathrec, sizeof pathrec); + memcpy(&pathrec, &path->pathrec, sizeof(pathrec)); spin_unlock_irqrestore(&priv->lock, flags); netif_tx_unlock_bh(dev);