linux-kernel - Re: Problem with VMAP

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]

Message-ID: <CADDKRnB13h4cZN7y_EumnbcxK_Bj6evntx56Ya9WuZ3fYCJTBg@mail.gmail.com>
Date:   Wed, 5 Oct 2016 18:45:05 +0200
From:   Jörg Otte <jrg.otte@...il.com>
To:     Andy Lutomirski <luto@...capital.net>
Cc:     Mauro Carvalho Chehab <mchehab@...pensource.com>,
        Jiri Kosina <jikos@...nel.org>,
        Patrick Boettcher <patrick.boettcher@...teo.de>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Andy Lutomirski <luto@...nel.org>,
        Michael Krufky <mkrufky@...uxtv.org>,
        Mauro Carvalho Chehab <mchehab@...nel.org>,
        Linux Media Mailing List <linux-media@...r.kernel.org>
Subject: Re: Problem with VMAP_STACK=y

2016-10-05 17:53 GMT+02:00 Andy Lutomirski <luto@...capital.net>:
> On Wed, Oct 5, 2016 at 8:21 AM, Jörg Otte <jrg.otte@...il.com> wrote:
>> 2016-10-05 11:04 GMT+02:00 Mauro Carvalho Chehab <mchehab@...pensource.com>:
>>> Em Wed, 5 Oct 2016 09:50:42 +0200 (CEST)
>>> Jiri Kosina <jikos@...nel.org> escreveu:
>>>
>>>> On Wed, 5 Oct 2016, Patrick Boettcher wrote:
>>>>
>>>> > > > Thanks for the quick response.
>>>> > > > Drivers are:
>>>> > > > dvb_core, dvb_usb, dbv_usb_cynergyT2
>>>> > >
>>>> > > This dbv_usb_cynergyT2 is not from Linus' tree, is it? I don't seem
>>>> > > to be able to find it, and the only google hit I am getting is your
>>>> > > very mail to LKML :)
>>>> >
>>>> > It's a typo, it should say dvb_usb_cinergyT2.
>>>>
>>>> Ah, thanks. Same issues there in
>>>>
>>>>       cinergyt2_frontend_attach()
>>>>       cinergyt2_rc_query()
>>>>
>>>> I think this would require more in-depth review of all the media drivers
>>>> and having all this fixed for 4.9. It should be pretty straightforward;
>>>> all the instances I've seen so far should be just straightforward
>>>> conversion to kmalloc() + kfree(), as the buffer is not being embedded in
>>>> any structure etc.
>>>
>>> What we're doing on most cases is to put a buffer (usually with 80
>>> chars for USB drivers) inside the "state" struct (on DVB drivers),
>>> in order to avoid doing kmalloc/kfree all the times. One such patch is
>>> changeset c4a98793a63c4.
>>>
>>> I'm enclosing a non-tested patch fixing it for the cinergyT2-core.c
>>> driver.
>>>
>>> Thanks,
>>> Mauro
>>>
>>> [PATCH] cinergyT2-core: don't do DMA on stack
>>>
>>
>> Tried the cinergyT2 patch. No success. When I select a TV channel
>> just nothing happens. There are no error messages.
>
> Could you try compiling with CONFIG_DEBUG_VIRTUAL=y and seeing if you
> get a nice error message?
>
> --Andy

Done. Still no error messages in dmesg and syslog.

DVB adapter signals it is tuned to the channel.
For me it looks like there`s no data reaching the application
(similar to if I forget to connect an antenna).

Jörg