Re: [PATCH v2] HID: hid-input: clear unmapped usages

[Benjamin Tissoires]

Hi,

On Fri, Dec 13, 2019 at 10:28 AM Jiri Kosina <jikos@xxxxxxxxxx> wrote:
>
> On Sat, 7 Dec 2019, Dmitry Torokhov wrote:
>
> > We should not be leaving half-mapped usages with potentially invalid
> > keycodes, as that may confuse hidinput_find_key() when the key is located
> > by index, which may end up feeding way too large keycode into the VT
> > keyboard handler and cause OOB write there:
> >
> > BUG: KASAN: global-out-of-bounds in clear_bit include/asm-generic/bitops-instrumented.h:56 [inline]
> > BUG: KASAN: global-out-of-bounds in kbd_keycode drivers/tty/vt/keyboard.c:1411 [inline]
> > BUG: KASAN: global-out-of-bounds in kbd_event+0xe6b/0x3790 drivers/tty/vt/keyboard.c:1495
> > Write of size 8 at addr ffffffff89a1b2d8 by task syz-executor108/1722
> > ...
> >  kbd_keycode drivers/tty/vt/keyboard.c:1411 [inline]
> >  kbd_event+0xe6b/0x3790 drivers/tty/vt/keyboard.c:1495
> >  input_to_handler+0x3b6/0x4c0 drivers/input/input.c:118
> >  input_pass_values.part.0+0x2e3/0x720 drivers/input/input.c:145
> >  input_pass_values drivers/input/input.c:949 [inline]
> >  input_set_keycode+0x290/0x320 drivers/input/input.c:954
> >  evdev_handle_set_keycode_v2+0xc4/0x120 drivers/input/evdev.c:882
> >  evdev_do_ioctl drivers/input/evdev.c:1150 [inline]
> >
> > Reported-by: syzbot+19340dff067c2d3835c0@xxxxxxxxxxxxxxxxxxxxxxxxx
> > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> > ---
> >
> > v2: fixed up interaction with hid-multitouch according to Benjamin's
> > feedback
> >
> > Please consider tagging for stable.
>
> I'd like to push this for 5.5 (and tag for stable), but would prefer this
> to have gone through the full battery of Benjamin's testing infrastructure
> first.
>
> Benjamin, did you have chance to run Dmitry's patch through your
> machinery?

yep, this one was OK, so:
Tested-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>

Cheers,
Benjamin

>
> Thanks,
>
> --
> Jiri Kosina
> SUSE Labs
>