Messages in this thread | | | Subject | Re: [PATCH v2] HID: betop: fix slab-out-of-bounds Write in betop_probe | From | Pavel Skripkin <> | Date | Sun, 22 Aug 2021 19:01:36 +0300 |
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On 8/22/21 4:43 PM, F.A.Sulaiman wrote: > Syzbot reported slab-out-of-bounds Write bug in hid-betopff driver. > The problem is the driver assumes the device must have an input report but > some malicious devices violate this assumption. > > So this patch checks hid_device's input is non empty before it's been used. > > Reported-by: syzbot+07efed3bc5a1407bd742@syzkaller.appspotmail.com > Signed-off-by: F.A. SULAIMAN <asha.16@itfac.mrt.ac.lk> > --- > drivers/hid/hid-betopff.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/hid/hid-betopff.c b/drivers/hid/hid-betopff.c > index 0790fbd3fc9a..2d62bde21413 100644 > --- a/drivers/hid/hid-betopff.c > +++ b/drivers/hid/hid-betopff.c > @@ -116,6 +116,11 @@ static int betop_probe(struct hid_device *hdev, const struct hid_device_id *id) > { > int ret; > > + if (list_empty(&hdev->inputs)) { > + hid_err(hdev, "no inputs found\n"); > + return -ENODEV; > + } > + > if (id->driver_data) > hdev->quirks |= HID_QUIRK_MULTI_INPUT; > >
I am still able to trigger reported slab-out-bound with this patch applied, please move this sanity check inside betopff_init().
Jiri, does it make sense to add proper error handling of betopff_init()? Nowadays betop_probe() just ignores betopff_init() return value. It looks wrong to me.
I think, Asha can prepare a patch series with these 2 changes
With regards, Pavel Skripkin
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