All of lore.kernel.org
 help / color / mirror / Atom feed
From: Arnd Bergmann <arnd@arndb.de>
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "Bartosz Golaszewski" <brgl@bgdev.pl>,
	"Dan Carpenter" <dan.carpenter@oracle.com>,
	"Linus Walleij" <linus.walleij@linaro.org>,
	"Peilin Ye" <yepeilin.cs@gmail.com>,
	"Mauro Carvalho Chehab" <mchehab@kernel.org>,
	"Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
	syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
	"Hans Verkuil" <hverkuil-cisco@xs4all.nl>,
	"Sakari Ailus" <sakari.ailus@linux.intel.com>,
	"Laurent Pinchart" <laurent.pinchart@ideasonboard.com>,
	"Vandana BN" <bnvandana@gmail.com>,
	"Ezequiel Garcia" <ezequiel@collabora.com>,
	"Niklas Söderlund" <niklas.soderlund+renesas@ragnatech.se>,
	linux-kernel-mentees@lists.linuxfoundation.org,
	"Linux Media Mailing List" <linux-media@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [Linux-kernel-mentees] [PATCH v3] media/v4l2-core: Fix kernel-infoleak in video_put_user()
Date: Thu, 30 Jul 2020 15:49:08 +0200	[thread overview]
Message-ID: <CAK8P3a2L1yK=XuS5vGj-einsNKU99ZdX53Ao5TUfc7_WU-LOYA@mail.gmail.com> (raw)
In-Reply-To: <20200730114842.GH3703480@smile.fi.intel.com>

On Thu, Jul 30, 2020 at 1:48 PM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
> On Thu, Jul 30, 2020 at 11:18:04AM +0200, Arnd Bergmann wrote:
> > The in_ia32_syscall() check should be completely reliable in telling whether
> > we are called from read() by an ia32 task or not, and we use the same
> > logic for input_event, which has a similar problem (on all compat architectures,
> > not just x86).
>
> By the way any reason why we have to have in_ia32_syscall() instead of
> in_compat_syscall()?

x86 is the only architecture that has different struct alignment between 32-bit
and 64-bit processes, so others don't have this particular problem. On top of
that, x86 also has two different 32-bit ABIs and only one of them needs the
workaround, while the other (x32) uses the same struct layout as x86-64 and
must use the normal code path.

       Arnd

WARNING: multiple messages have this Message-ID (diff)
From: Arnd Bergmann <arnd@arndb.de>
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: "Niklas Söderlund" <niklas.soderlund+renesas@ragnatech.se>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"Bartosz Golaszewski" <brgl@bgdev.pl>,
	syzkaller-bugs <syzkaller-bugs@googlegroups.com>,
	"Linux Media Mailing List" <linux-media@vger.kernel.org>,
	"Peilin Ye" <yepeilin.cs@gmail.com>,
	"Laurent Pinchart" <laurent.pinchart@ideasonboard.com>,
	"Sakari Ailus" <sakari.ailus@linux.intel.com>,
	"Vandana BN" <bnvandana@gmail.com>,
	"Hans Verkuil" <hverkuil-cisco@xs4all.nl>,
	"Mauro Carvalho Chehab" <mchehab@kernel.org>,
	"Ezequiel Garcia" <ezequiel@collabora.com>,
	"Linus Walleij" <linus.walleij@linaro.org>,
	"Dan Carpenter" <dan.carpenter@oracle.com>,
	linux-kernel-mentees@lists.linuxfoundation.org
Subject: Re: [Linux-kernel-mentees] [PATCH v3] media/v4l2-core: Fix kernel-infoleak in video_put_user()
Date: Thu, 30 Jul 2020 15:49:08 +0200	[thread overview]
Message-ID: <CAK8P3a2L1yK=XuS5vGj-einsNKU99ZdX53Ao5TUfc7_WU-LOYA@mail.gmail.com> (raw)
In-Reply-To: <20200730114842.GH3703480@smile.fi.intel.com>

On Thu, Jul 30, 2020 at 1:48 PM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
> On Thu, Jul 30, 2020 at 11:18:04AM +0200, Arnd Bergmann wrote:
> > The in_ia32_syscall() check should be completely reliable in telling whether
> > we are called from read() by an ia32 task or not, and we use the same
> > logic for input_event, which has a similar problem (on all compat architectures,
> > not just x86).
>
> By the way any reason why we have to have in_ia32_syscall() instead of
> in_compat_syscall()?

x86 is the only architecture that has different struct alignment between 32-bit
and 64-bit processes, so others don't have this particular problem. On top of
that, x86 also has two different 32-bit ABIs and only one of them needs the
workaround, while the other (x32) uses the same struct layout as x86-64 and
must use the normal code path.

       Arnd
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

  reply	other threads:[~2020-07-30 13:49 UTC|newest]

Thread overview: 76+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-26 16:44 [Linux-kernel-mentees] [PATCH] media/v4l2-core: Fix kernel-infoleak in video_put_user() Peilin Ye
2020-07-26 16:44 ` Peilin Ye
2020-07-26 17:30 ` Laurent Pinchart
2020-07-26 17:30   ` Laurent Pinchart
2020-07-26 18:07   ` Peilin Ye
2020-07-26 18:07     ` Peilin Ye
2020-07-26 22:08     ` Laurent Pinchart
2020-07-26 22:08       ` Laurent Pinchart
2020-07-26 22:15       ` Peilin Ye
2020-07-26 22:15         ` Peilin Ye
2020-07-26 18:12   ` Peilin Ye
2020-07-26 18:12     ` Peilin Ye
2020-07-26 22:05 ` [Linux-kernel-mentees] [PATCH v2] " Peilin Ye
2020-07-26 22:05   ` Peilin Ye
2020-07-26 22:10   ` Laurent Pinchart
2020-07-26 22:10     ` Laurent Pinchart
2020-07-26 22:16     ` Peilin Ye
2020-07-26 22:16       ` Peilin Ye
2020-07-26 22:27   ` [Linux-kernel-mentees] [PATCH v3] " Peilin Ye
2020-07-26 22:27     ` Peilin Ye
2020-07-27  7:25     ` Arnd Bergmann
2020-07-27  7:25       ` Arnd Bergmann
2020-07-27  7:56       ` Peilin Ye
2020-07-27  7:56         ` Peilin Ye
2020-07-27 13:16       ` Dan Carpenter
2020-07-27 13:16         ` Dan Carpenter
2020-07-27 14:05         ` Arnd Bergmann
2020-07-27 14:05           ` Arnd Bergmann
2020-07-27 14:14           ` Peilin Ye
2020-07-27 14:14             ` Peilin Ye
2020-07-27 14:20             ` Arnd Bergmann
2020-07-27 14:20               ` Arnd Bergmann
2020-07-27 14:46             ` Dan Carpenter
2020-07-27 14:46               ` Dan Carpenter
2020-07-27 15:30               ` Peilin Ye
2020-07-27 15:30                 ` Peilin Ye
2020-07-27 14:43           ` Dan Carpenter
2020-07-27 14:43             ` Dan Carpenter
2020-07-27 14:55             ` Arnd Bergmann
2020-07-27 14:55               ` Arnd Bergmann
2020-07-27 22:04         ` Peilin Ye
2020-07-27 22:04           ` Peilin Ye
2020-07-28  9:00           ` Arnd Bergmann
2020-07-28  9:00             ` Arnd Bergmann
2020-07-28 10:02           ` Dan Carpenter
2020-07-28 10:02             ` Dan Carpenter
2020-07-27 22:33         ` Peilin Ye
2020-07-27 22:33           ` Peilin Ye
2020-07-28  9:10           ` Arnd Bergmann
2020-07-28  9:10             ` Arnd Bergmann
2020-07-28  9:47           ` Dan Carpenter
2020-07-28  9:47             ` Dan Carpenter
2020-07-28 13:13             ` Peilin Ye
2020-07-28 13:13               ` Peilin Ye
2020-07-28 12:22         ` Linus Walleij
2020-07-28 12:22           ` Linus Walleij
2020-07-28 13:06           ` Dan Carpenter
2020-07-28 13:06             ` Dan Carpenter
2020-07-28 13:58             ` Arnd Bergmann
2020-07-28 13:58               ` Arnd Bergmann
2020-07-30  8:07               ` Bartosz Golaszewski
2020-07-30  8:07                 ` Bartosz Golaszewski
2020-07-30  8:15                 ` Arnd Bergmann
2020-07-30  8:15                   ` Arnd Bergmann
2020-07-30  8:38                   ` Andy Shevchenko
2020-07-30  8:38                     ` Andy Shevchenko
2020-07-30  9:18                     ` Arnd Bergmann
2020-07-30  9:18                       ` Arnd Bergmann
2020-07-30 11:48                       ` Andy Shevchenko
2020-07-30 11:48                         ` Andy Shevchenko
2020-07-30 13:49                         ` Arnd Bergmann [this message]
2020-07-30 13:49                           ` Arnd Bergmann
2020-08-02 16:55         ` Peilin Ye
2020-08-02 16:55           ` Peilin Ye
2020-07-27  8:00     ` [Linux-kernel-mentees] [PATCH v4] " Peilin Ye
2020-07-27  8:00       ` Peilin Ye

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='CAK8P3a2L1yK=XuS5vGj-einsNKU99ZdX53Ao5TUfc7_WU-LOYA@mail.gmail.com' \
    --to=arnd@arndb.de \
    --cc=andriy.shevchenko@linux.intel.com \
    --cc=bnvandana@gmail.com \
    --cc=brgl@bgdev.pl \
    --cc=dan.carpenter@oracle.com \
    --cc=ezequiel@collabora.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hverkuil-cisco@xs4all.nl \
    --cc=laurent.pinchart@ideasonboard.com \
    --cc=linus.walleij@linaro.org \
    --cc=linux-kernel-mentees@lists.linuxfoundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=mchehab@kernel.org \
    --cc=niklas.soderlund+renesas@ragnatech.se \
    --cc=sakari.ailus@linux.intel.com \
    --cc=syzkaller-bugs@googlegroups.com \
    --cc=yepeilin.cs@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.