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Date: Tue, 30 Apr 2024 04:00:02 +0300
From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
To: Jameson Thies <jthies@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, 
	Markus Elfring <Markus.Elfring@web.de>, Abhishek Pandit-Subedi <abhishekpandit@chromium.org>, 
	linux-usb@vger.kernel.org, kernel-janitors@vger.kernel.org, 
	Heikki Krogerus <heikki.krogerus@linux.intel.com>, LKML <linux-kernel@vger.kernel.org>, 
	Benson Leung <bleung@google.com>, Bjorn Andersson <andersson@kernel.org>, 
	Fabrice Gasnier <fabrice.gasnier@foss.st.com>, Hans de Goede <hdegoede@redhat.com>, 
	Neil Armstrong <neil.armstrong@linaro.org>, Prashant Malani <pmalani@chromium.org>, 
	Rajaram Regupathy <rajaram.regupathy@intel.com>, Saranya Gopal <saranya.gopal@intel.com>, 
	Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de>
Subject: Re: [PATCH v2 1/4] usb: typec: ucsi: Fix null deref in trace
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On Mon, Apr 29, 2024 at 05:43:16PM -0700, Jameson Thies wrote:
> Hi Dmitry,
> what are your thoughts on Abhishek's comment? I think we should
> attempt to register the alternate mode when CONFIG_TYPEC_DP_ALTMODE is
> not enabled. It would give us a more accurate representation of the
> partner in user space. I understand your point about ignoring a
> potential EOPNOTSUPP response from the non-stub function. What if we
> leave ucsi.c alone, and replace the stub function's null return with a
> call to typec_port_register_altmode(). That would register DP altmode
> as an unsupported mode when CONFIG_TYPEC_DP_ALTMODE is not enabled,
> and fix the null pointer dereference. But, it won't change behavior
> when CONFIG_TYPEC_DP_ALTMODE is enabled.

Yes, this sounds like a perfect idea!

> 
> Hi Markus,
> thanks for your feedback. I'll update the commit message to say "null
> pointer dereference" when I upload a v3 series.
> 
> Thanks,
> Jameson

-- 
With best wishes
Dmitry