On Wed, 26 Aug 2020, Marc Zyngier wrote: > When calling into hid_map_usage(), the passed event code is > blindly stored as is, even if it doesn't fit in the associated bitmap. > > This event code can come from a variety of sources, including devices > masquerading as input devices, only a bit more "programmable". > > Instead of taking the event code at face value, check that it actually > fits the corresponding bitmap, and if it doesn't: > - spit out a warning so that we know which device is acting up > - NULLify the bitmap pointer so that we catch unexpected uses > > Code paths that can make use of untrusted inputs can now check > that the mapping was indeed correct and bail out if not. > > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> > --- > * From v1: > - Dropped the input.c changes, and turned hid_map_usage() into > the validation primitive. > - Handle mapping failures in hidinput_configure_usage() and > mt_touch_input_mapping() (on top of hid_map_usage_clear() which > was already handled) Benjamin, could you please run this through your regression testing machinery? It's a non-trivial core change, at the same time I'd like not to postpone it for 5.10 due to its nature. Thanks, -- Jiri Kosina SUSE Labs
