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Date:   Thu, 8 Dec 2022 10:01:35 +0800
From:   Tzung-Bi Shih <tzungbi@kernel.org>
To:     Prashant Malani <pmalani@chromium.org>
Cc:     Victor Ding <victording@chromium.org>,
        linux-kernel@vger.kernel.org, chrome-platform@lists.linux.dev,
        groeck@chromium.org, dustin@howett.net, gustavoars@kernel.org,
        gregkh@linuxfoundation.org, sebastian.reichel@collabora.com,
        dnojiri@chromium.org, lee.jones@linaro.org, bleung@chromium.org,
        tinghan.shen@mediatek.com,
        Enric Balletbo i Serra <enric.balletbo@collabora.com>,
        Heikki Krogerus <heikki.krogerus@linux.intel.com>
Subject: Re: [PATCH v2] platform/chrome: cros_ec_typec: zero out stale
 pointers
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References: <20221207093924.v2.1.I1864b6a7ee98824118b93677868d22d3750f439b@changeid>
 <Y5EZmSSbOFRpfBNj@chromium.org>
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On Wed, Dec 07, 2022 at 10:54:17PM +0000, Prashant Malani wrote:
> On Dec 07 09:39, Victor Ding wrote:
> > `cros_typec_get_switch_handles` allocates four pointers when obtaining
> > type-c switch handles. These pointers are all freed if failing to obtain
> > any of them; therefore, pointers in `port` become stale. The stale
> > pointers eventually cause use-after-free or double free in later code
> > paths. Zeroing out all pointer fields after freeing to eliminate these
> > stale pointers.
> > 
> > Fixes: f28adb41dab4 ("platform/chrome: cros_ec_typec: Register Type C switches")
> > Fixes: 1a8912caba02 ("platform/chrome: cros_ec_typec: Get retimer handle")
> > Signed-off-by: Victor Ding <victording@chromium.org>
> Acked-by: Prashant Malani <pmalani@chromium.org>
> 
> Hey Tzung-Bi, it looks like you've already created a tag for the
> v6.2 pull request, so I don't know if it's too late to apply this
> for the current dev cycle.
> So, I've not applied it, but have left the Acked-by tag.
> 
> Please feel free to apply it if there's still room for it before
> you send out the pull request.

Given that the patch fixes an use-after-free, let's include this in the
coming merge window.  Have queued.