In the Linux kernel, the following vulnerability has been resolved:
drm/bridge: samsung-dsim: fix TE GPIO lifetime for host attach
When the Exynos DSI driver was generalized into samsung-dsim, the TE
GPIO acquisition was switched from gpiod_get_optional() to
devm_gpiod_get_optional() while keeping the matching gpiod_put() calls.
That combination is wrong for a managed descriptor.
However, dropping the puts and keeping the managed get is also wrong:
samsung_dsim_register_te_irq() runs from the DSI host attach callback,
and host detach/reattach can happen without destroying the device that
owns the managed action. A second attach would then request the GPIO
again without having released it.
Switch back to a non-managed gpiod_get_optional() and keep the explicit
gpiod_put() on the request_irq() error path and in
samsung_dsim_unregister_te_irq().
[Luca: remove unnecessary comment]
