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:   Wed, 17 May 2023 03:32:26 -0700
From:   Badhri Jagan Sridharan <badhri@...gle.com>
To:     Linux regressions mailing list <regressions@...ts.linux.dev>
Cc:     Alistair <alistair@...stair23.me>, gregkh@...uxfoundation.org,
        stern@...land.harvard.edu, colin.i.king@...il.com,
        xuetao09@...wei.com, quic_eserrao@...cinc.com,
        water.zhangjiantao@...wei.com, peter.chen@...escale.com,
        balbi@...com, linux-usb@...r.kernel.org,
        linux-kernel@...r.kernel.org, stable@...r.kernel.org,
        Francesco Dolcini <francesco@...cini.it>
Subject: Re: [PATCH v4 1/2] usb: gadget: udc: core: Invoke usb_gadget_connect
 only when started

Hi Thorsten,

Francesso  had shared the stack dump as well at
https://lore.kernel.org/all/ZGMm2sxN6wW%2FEWrR@francesco-nb.int.toradex.com/.
I am working on a fix based on that. Going to share it in the next
hour and would be requesting Franceso and others help to see if the
regression goes away.

Thanks,
Badhri


On Wed, May 17, 2023 at 3:23 AM Linux regression tracking (Thorsten
Leemhuis) <regressions@...mhuis.info> wrote:
>
> [CCing Francesco Dolcini; and the regression list too, as it should be
> in the loop for regressions:
> https://docs.kernel.org/admin-guide/reporting-regressions.html]
>
> On 16.05.23 14:53, Alistair wrote:
> > On Fri, 2023-04-07 at 03:07 +0000, Badhri Jagan Sridharan wrote:
> >> usb_udc_connect_control does not check to see if the udc has already
> >> been started. This causes gadget->ops->pullup to be called through
> >> usb_gadget_connect when invoked from usb_udc_vbus_handler even before
> >> usb_gadget_udc_start is called. Guard this by checking for udc-
> >>> started
> >> in usb_udc_connect_control before invoking usb_gadget_connect.
> > [...]
> >> Cc: stable@...r.kernel.org
> >> Fixes: 628ef0d273a6 ("usb: udc: add usb_udc_vbus_handler")
> >> Signed-off-by: Badhri Jagan Sridharan <badhri@...gle.com>
> >
> > This patch causes a kernel hang when trying to boot with the
> > usb/chipidea/udc.c driver.
> >
> > The call stack below causes the hang:
> >
> >  - gadget_bind_driver(struct device *dev)
> >     - mutex_lock(&udc->connect_lock);
> >     - usb_gadget_udc_start_locked(struct usb_udc *udc)
> >         - udc->gadget->ops->udc_start(udc->gadget, udc->driver)
> >
> > At which point we are calling ci_udc_start(..), but with the
> > connect_lock mutex locked.
> >
> > ci_udc_start() then calls usb_udc_vbus_handler() which tries to lock
> > the connect_lock while it's already locked. Resulting in a kernel hang.
> >
> > Reverting this patch fixes the hang.
>
> Not my area of expertise, but I guess it might be the same error as this
> one:
>
> https://lore.kernel.org/all/ZF4BvgsOyoKxdPFF@francesco-nb.int.toradex.com/
>
> Francesco sent a revert on Friday, but no reaction from Badhri Jagan
> Sridharan or Greg yet afaics.
>
> https://lore.kernel.org/all/20230512131435.205464-1-francesco@dolcini.it/
>
> Ciao, Thorsten

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ