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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 58224C433EF for ; Wed, 24 Nov 2021 14:09:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350138AbhKXOMs (ORCPT ); Wed, 24 Nov 2021 09:12:48 -0500 Received: from mail.kernel.org ([198.145.29.99]:57142 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354597AbhKXOI0 (ORCPT ); Wed, 24 Nov 2021 09:08:26 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 39B1B613AD; Wed, 24 Nov 2021 13:15:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637759713; bh=drosgPC9YmQkwX7TqquI1QNkbudQ1d9rfHOJEZiUvaY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jDh6HFSxb741/RwnoMfiahC9mi57pXU3CRpia2kjPj5dxUA2Jh798e/RPoEQ0mUxc DtwomeiKsK7LCxrpz9Pxrw0iUQdg1xmQHVwUhy9QhCQZpzDCbjNJurwkQm5OYC9nxK qw4M8AIH4OYi4k4JdlH6U6dhmgvlVOIPcu+EF3j8= Date: Wed, 24 Nov 2021 14:15:10 +0100 From: Greg Kroah-Hartman To: Jason Gunthorpe Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, syzbot+e4df4e1389e28972e955@syzkaller.appspotmail.com, Ziyang Xuan , "David S. Miller" , Sasha Levin Subject: Re: [PATCH 4.14 181/251] net: vlan: fix a UAF in vlan_dev_real_dev() Message-ID: References: <20211124115710.214900256@linuxfoundation.org> <20211124115716.547727004@linuxfoundation.org> <20211124125018.GG4670@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211124125018.GG4670@nvidia.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 24, 2021 at 08:50:18AM -0400, Jason Gunthorpe wrote: > On Wed, Nov 24, 2021 at 12:57:03PM +0100, Greg Kroah-Hartman wrote: > > From: Ziyang Xuan > > > > [ Upstream commit 563bcbae3ba233c275c244bfce2efe12938f5363 ] > > > > The real_dev of a vlan net_device may be freed after > > unregister_vlan_dev(). Access the real_dev continually by > > vlan_dev_real_dev() will trigger the UAF problem for the > > real_dev like following: > > > > ================================================================== > > BUG: KASAN: use-after-free in vlan_dev_real_dev+0xf9/0x120 > > Call Trace: > > 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 > > ... > > > > 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 > > ... > > > > Move the put_device(real_dev) to vlan_dev_free(). Ensure > > real_dev not be freed before vlan_dev unregistered. > > > > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") > > Reported-by: syzbot+e4df4e1389e28972e955@syzkaller.appspotmail.com > > Signed-off-by: Ziyang Xuan > > Reviewed-by: Jason Gunthorpe > > Signed-off-by: David S. Miller > > Signed-off-by: Sasha Levin > > --- > > net/8021q/vlan.c | 3 --- > > net/8021q/vlan_dev.c | 3 +++ > > 2 files changed, 3 insertions(+), 3 deletions(-) > > This patch is known to be broken, it should not be backported It is already in a bunch of branches :( What is the upstream revert of this commit in Linus's tree? thanks, greg k-h