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From: Pavan Holla <pholla@chromium.org>
Date: Thu, 4 Apr 2024 13:44:29 -0700
Message-ID: <CAB2FV=4TQZwM6bRSeBhieqU2H8yxt3NWsey55a5my_i1La0fJQ@mail.gmail.com>
Subject: Re: [PATCH v3 2/2] usb: typec: ucsi: Implement ChromeOS UCSI driver
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>, 
	Heikki Krogerus <heikki.krogerus@linux.intel.com>, Benson Leung <bleung@chromium.org>, 
	Tzung-Bi Shih <tzungbi@kernel.org>, Guenter Roeck <groeck@chromium.org>, linux-kernel@vger.kernel.org, 
	linux-usb@vger.kernel.org, 
	Abhishek Pandit-Subedi <abhishekpandit@chromium.org>, chrome-platform@lists.linux.dev
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On Thu, Apr 4, 2024 at 6:07=E2=80=AFAM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> On Wed, Apr 03, 2024 at 09:58:33PM +0300, Dmitry Baryshkov wrote:
> > I think it's better be written as
> >
> > if (WARN_ON_ONCE(val_len > MAX_EC_DATA_SIZE))
> >       return -EINVAL;
>
> So if you trigger this, you just rebooted all boxes that have
> panic-on-warn enabled (hint, the HUGE majority in quantity of Linux
> systems out there.)
>
> So don't do that, just handle it like this.
>
> BUT, if this can be triggered by userspace, do NOT use dev_err() as that
> will just allow userspace to flood the kernel log.
>
> Pavan, who calls this?  If userspace, this needs to be fixed.  If it's
> only a kernel driver, it's fine as-is.

This code is only called by a kernel driver.

Thanks,
Pavan