linux-kernel - Re: [PATCH] rfkill: Fix use-after-free in rfkill

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 10 Nov 2020 18:35:07 +0100
From:   Johannes Berg <johannes@...solutions.net>
To:     Claire Chang <tientzu@...omium.org>, davem@...emloft.net,
        kuba@...nel.org, hdegoede@...hat.com, marcel@...tmann.org
Cc:     linux-wireless@...r.kernel.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] rfkill: Fix use-after-free in rfkill_resume()

On Tue, 2020-11-10 at 16:49 +0800, Claire Chang wrote:
> If a device is getting removed or reprobed during resume, use-after-free
> might happen. For example, h5_btrtl_resume()[drivers/bluetooth/hci_h5.c]
> schedules a work queue for device reprobing. During the reprobing, if
> rfkill_set_block() in rfkill_resume() is called after the corresponding
> *_unregister() and kfree() are called, there will be an use-after-free
> in hci_rfkill_set_block()[net/bluetooth/hci_core.c].


Not sure I understand. So you're saying

 * something (h5_btrtl_resume) schedules a worker
 * said worker run, when it runs, calls rfkill_unregister()
 * somehow rfkill_resume() still gets called after this

But that can't really be right, device_del() removes it from the PM
lists?

johannes