From: Jason Gunthorpe <jgg@nvidia.com>
To: Ziyang Xuan <william.xuanziyang@huawei.com>,
Jiri Pirko <jiri@nvidia.com>
Cc: dledford@redhat.com, leon@kernel.org, mbloch@nvidia.com,
jinpu.wang@ionos.com, lee.jones@linaro.org,
linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH rdma-rc] IB/core: fix a UAF for netdev in netdevice_event process
Date: Mon, 25 Oct 2021 13:39:41 -0300 [thread overview]
Message-ID: <20211025163941.GA393143@nvidia.com> (raw)
In-Reply-To: <20211025034258.2426872-1-william.xuanziyang@huawei.com>
On Mon, Oct 25, 2021 at 11:42:58AM +0800, Ziyang Xuan wrote:
> 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:
I think this is a netdev bug. Under rtnl vlan_dev_real_dev() should
return NULL if the vlan device has passed unregister_vlan_dev()
diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
index 55275ef9a31a7c..1106da84e72559 100644
--- a/net/8021q/vlan.c
+++ b/net/8021q/vlan.c
@@ -126,6 +126,7 @@ void unregister_vlan_dev(struct net_device *dev, struct list_head *head)
/* Get rid of the vlan's reference to real_dev */
dev_put(real_dev);
+ vlan->real_dev = NULL;
}
int vlan_check_real_dev(struct net_device *real_dev,
I'm assuming there is more too it than this, but it is a starting
point.
Jason
prev parent reply other threads:[~2021-10-25 16:39 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-25 3:42 [PATCH rdma-rc] IB/core: fix a UAF for netdev in netdevice_event process Ziyang Xuan
2021-10-25 7:33 ` Leon Romanovsky
2021-10-25 8:37 ` Ziyang Xuan (William)
2021-10-25 11:06 ` Leon Romanovsky
2021-10-26 3:14 ` Ziyang Xuan (William)
2021-10-26 9:03 ` Leon Romanovsky
2021-10-25 16:39 ` Jason Gunthorpe [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20211025163941.GA393143@nvidia.com \
--to=jgg@nvidia.com \
--cc=dledford@redhat.com \
--cc=jinpu.wang@ionos.com \
--cc=jiri@nvidia.com \
--cc=lee.jones@linaro.org \
--cc=leon@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rdma@vger.kernel.org \
--cc=mbloch@nvidia.com \
--cc=william.xuanziyang@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).