From: Greg KH <gregkh@linuxfoundation.org>
To: "Schmid, Carsten" <Carsten_Schmid@mentor.com>
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>,
USB list <linux-usb@vger.kernel.org>
Subject: Re: Possible race in 4.14 xhci stack
Date: Wed, 21 Jul 2021 10:14:28 +0200 [thread overview]
Message-ID: <YPfXZBtd48oL7DaQ@kroah.com> (raw)
In-Reply-To: <2c52cd176b134e6ab7806aeda8fcca1d@SVR-IES-MBX-03.mgc.mentorg.com>
On Wed, Jul 21, 2021 at 07:51:58AM +0000, Schmid, Carsten wrote:
> Hi Greg,
>
> >> Hi Mathias,
> >>
> >> i got a NULL pointer deref in the usbfs and analyzed it.
> >> The connected device seemed to have trouble on USB transmissions.
> >> However, I have the impression that there is a race between finishing URB handling and disconnection of devices.
> >> In detail:
> >> [ 4979.029666] xhci_hcd 0000:00:15.0: USB transfer error. Maybe the USB cable is bad?
> >
> > Did your cable die?
> >
> > And 4.14 is quite old, what about 5.13?
> >
> > thanks,
> >
> > greg k-h
>
> That was reported from a device in the field.
> Yes, a defective cable is bad, but shouldn't the kernel's health avoid a NULL pointer deref?
Yes, I am not disagreeing about that, patches always welcome :)
thanks,
greg k-h
next prev parent reply other threads:[~2021-07-21 8:22 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-20 15:04 Possible race in 4.14 xhci stack Schmid, Carsten
2021-07-20 16:11 ` Greg KH
2021-07-21 7:51 ` Schmid, Carsten
2021-07-21 8:14 ` Greg KH [this message]
2021-07-23 19:43 ` Mathias Nyman
2021-07-26 7:10 ` Schmid, Carsten
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=YPfXZBtd48oL7DaQ@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=Carsten_Schmid@mentor.com \
--cc=linux-usb@vger.kernel.org \
--cc=mathias.nyman@linux.intel.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).