On Mon, 14 Dec 2020, Will McVicker wrote:
> > The HID subsystem allows an "HID report field" to have a different
> > number of "values" and "usages" when it is allocated. When a field
> > struct is created, the size of the usage array is guaranteed to be at
> > least as large as the values array, but it may be larger. This leads to
> > a potential out-of-bounds write in
> > __hidinput_change_resolution_multipliers() and an out-of-bounds read in
> > hidinput_count_leds().
> >
> > To fix this, let's make sure that both the usage and value arrays are
> > the same size.
> >
> > Signed-off-by: Will McVicker <willmcvic...@google.com>
> > ---
> > drivers/hid/hid-core.c | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
> > index 56172fe6995c..8a8b2b982f83 100644
> > --- a/drivers/hid/hid-core.c
> > +++ b/drivers/hid/hid-core.c
> > @@ -90,7 +90,7 @@ EXPORT_SYMBOL_GPL(hid_register_report);
> > * Register a new field for this report.
> > */
> >
> > -static struct hid_field *hid_register_field(struct hid_report *report,
> > unsigned usages, unsigned values)
> > +static struct hid_field *hid_register_field(struct hid_report *report,
> > unsigned usages)
> > {
> > struct hid_field *field;
> >
> > @@ -101,7 +101,7 @@ static struct hid_field *hid_register_field(struct
> > hid_report *report, unsigned
> >
> > field = kzalloc((sizeof(struct hid_field) +
> > usages * sizeof(struct hid_usage) +
> > - values * sizeof(unsigned)), GFP_KERNEL);
> > + usages * sizeof(unsigned)), GFP_KERNEL);
> > if (!field)
> > return NULL;
> >
> > @@ -300,7 +300,7 @@ static int hid_add_field(struct hid_parser *parser,
> > unsigned report_type, unsign
> > usages = max_t(unsigned, parser->local.usage_index,
> > parser->global.report_count);
> >
> > - field = hid_register_field(report, usages, parser->global.report_count);
> > + field = hid_register_field(report, usages);
> > if (!field)
> > return 0;
> >
> > --
> > 2.29.2.576.ga3fc446d84-goog
> >
>
> Hi Jiri and Benjamin,
>
> This is a friendly reminder in case this got lost in your inbox.
Hi Will,
I am planning to merge it once the merge window is over.
--
Jiri Kosina
SUSE Labs
