Re: [PATCH v3 6/6] x86/vPIC: check values loaded from state save record

[Roger Pau Monné <roger.pau@xxxxxxxxxx>]

On Tue, Nov 28, 2023 at 11:36:40AM +0100, Jan Beulich wrote:
> Loading is_master from the state save record can lead to out-of-bounds
> accesses via at least the two container_of() uses by vpic_domain() and
> __vpic_lock(). Make sure the value is consistent with the instance being
> loaded.
> 
> For ->int_output (which for whatever reason isn't a 1-bit bitfield),
> besides bounds checking also take ->init_state into account.
> 
> For ELCR follow what vpic_intercept_elcr_io()'s write path and
> vpic_reset() do, i.e. don't insist on the internal view of the value to
> be saved.
> 
> Move the instance range check as well, leaving just an assertion in the
> load handler.
> 
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

Reviewed-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>

Thanks, Roger.