From: Oliver Neukum <oneukum@suse.com>
To: Shuah Khan <skhan@linuxfoundation.org>,
valentina.manea.m@gmail.com, shuah@kernel.org, i@zenithal.me,
gregkh@linuxfoundation.org, linux-usb@vger.kernel.org
Subject: Re: [PATCH] usb: vhci-hcd: Do not drop references before new references are gained
Date: Tue, 16 Jul 2024 16:33:38 +0200 [thread overview]
Message-ID: <f8b192bd-55e3-4b00-92b3-67ba99b5b86e@suse.com> (raw)
In-Reply-To: <e1b713a6-de8d-4df9-979e-12cb9876bf33@linuxfoundation.org>
On 09.07.24 21:38, Shuah Khan wrote:
> On 7/9/24 05:38, Oliver Neukum wrote:
>> At a few places the driver carries stale pointers
>> to references that can still be used. Make sure that does not happen.
>> This strictly speaking closes ZDI-CAN-22273, though there may be
>> similar races in the driver.
>>
>> Signed-off-by: Oliver Neukum <oneukum@suse.com>
>
> Sorry I need a bit more explanation to follow the change you
> are making. Also how did you find the problem?
Hi,
I looked at the initial report you wrote and it seemed to me that the issue
was that vhci_device_reset() leaves a stale pointer around and vhci_urb_enqueue()
in the special cases drops the old reference before it gets a new reference,
which together causes the race condition you were hitting.
Regards
Oliver
next prev parent reply other threads:[~2024-07-16 14:33 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-07-09 11:38 [PATCH] usb: vhci-hcd: Do not drop references before new references are gained Oliver Neukum
2024-07-09 19:38 ` Shuah Khan
2024-07-16 14:33 ` Oliver Neukum [this message]
2024-07-17 21:26 ` Shuah Khan
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=f8b192bd-55e3-4b00-92b3-67ba99b5b86e@suse.com \
--to=oneukum@suse.com \
--cc=gregkh@linuxfoundation.org \
--cc=i@zenithal.me \
--cc=linux-usb@vger.kernel.org \
--cc=shuah@kernel.org \
--cc=skhan@linuxfoundation.org \
--cc=valentina.manea.m@gmail.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