Re: [PATCH v2] platform/chrome: cros_ec_typec: zero out stale pointers
From: Tzung-Bi Shih
Date: Wed Dec 07 2022 - 21:01:48 EST
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@xxxxxxxxxxxx>
> Acked-by: Prashant Malani <pmalani@xxxxxxxxxxxx>
>
> 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.