linux-stable.git/drivers/hid/hid-input.c, branch linux-3.14.y

HID: hid-input: Add parentheses to quell gcc warning

2016-09-11T07:59:58+00:00

commit 09a5c34e8d6b05663ec4c3d22b1fbd9fec89aaf9 upstream.

GCC reports a -Wlogical-not-parentheses warning here; therefore
add parentheses to shut it up and to express our intent more.

Signed-off-by: James C Boyd 
Signed-off-by: Jiri Kosina 
Cc: Willy Tarreau 
Signed-off-by: Greg Kroah-Hartman

HID: fixup the conflicting keyboard mappings quirk

2015-03-18T12:31:33+00:00

commit 8e7b341037db1835ee6eea64663013cbfcf33575 upstream.

The ignore check that got added in 6ce901eb61 ("HID: input: fix confusion
on conflicting mappings") needs to properly check for VARIABLE reports
as well (ARRAY reports should be ignored), otherwise legitimate keyboards
might break.

Fixes: 6ce901eb61 ("HID: input: fix confusion on conflicting mappings")
Reported-by: Fredrik Hallenberg 
Reported-by: David Herrmann 
Signed-off-by: Jiri Kosina 
Signed-off-by: Greg Kroah-Hartman

HID: input: fix confusion on conflicting mappings

2015-03-18T12:31:33+00:00

commit 6ce901eb61aa30ba8565c62049ee80c90728ef14 upstream.

On an PC-101/103/104 keyboard (American layout) the 'Enter' key and its
neighbours look like this:

           +---+ +---+ +-------+
           | 1 | | 2 | |   5   |
           +---+ +---+ +-------+
             +---+ +-----------+
             | 3 | |     4     |
             +---+ +-----------+

On a PC-102/105 keyboard (European layout) it looks like this:

           +---+ +---+ +-------+
           | 1 | | 2 | |       |
           +---+ +---+ +-+  4  |
             +---+ +---+ |     |
             | 3 | | 5 | |     |
             +---+ +---+ +-----+

(Note that the number of keys is the same, but key '5' is moved down and
 the shape of key '4' is changed. Keys '1' to '3' are exactly the same.)

The keys 1-4 report the same scan-code in HID in both layouts, even though
the keysym they produce is usually different depending on the XKB-keymap
used by user-space.
However, key '5' (US 'backslash'/'pipe') reports 0x31 for the upper layout
and 0x32 for the lower layout, as defined by the HID spec. This is highly
confusing as the linux-input API uses a single keycode for both.

So far, this was never a problem as there never has been a keyboard with
both of those keys present at the same time. It would have to look
something like this:

           +---+ +---+ +-------+
           | 1 | | 2 | |  x31  |
           +---+ +---+ +-------+
             +---+ +---+ +-----+
             | 3 | |x32| |  4  |
             +---+ +---+ +-----+

HID can represent such a keyboard, but the linux-input API cannot.
Furthermore, any user-space mapping would be confused by this and,
luckily, no-one ever produced such hardware.

Now, the HID input layer fixed this mess by mapping both 0x31 and 0x32 to
the same keycode (KEY_BACKSLASH==0x2b). As only one of both physical keys
is present on a hardware, this works just fine.

Lets introduce hardware-vendors into this:
------------------------------------------

Unfortunately, it seems way to expensive to produce a different device for
American and European layouts. Therefore, hardware-vendors put both keys,
(0x31 and 0x32) on the same keyboard, but only one of them is hooked up
to the physical button, the other one is 'dead'.
This means, they can use the same hardware, with a different button-layout
and automatically produce the correct HID events for American *and*
European layouts. This is unproblematic for normal keyboards, as the
'dead' key will never report any KEY-DOWN events. But RollOver keyboards
send the whole matrix on each key-event, allowing n-key roll-over mode.
This means, we get a 0x31 and 0x32 event on each key-press. One of them
will always be 0, the other reports the real state. As we map both to the
same keycode, we will get spurious key-events, even though the real
key-state never changed.

The easiest way would be to blacklist 'dead' keys and never handle those.
We could simply read the 'country' tag of USB devices and blacklist either
key according to the layout. But... hardware vendors... want the same
device for all countries and thus many of them set 'country' to 0 for all
devices. Meh..

So we have to deal with this properly. As we cannot know which of the keys
is 'dead', we either need a heuristic and track those keys, or we simply
make use of our value-tracking for HID fields. We simply ignore HID events
for absolute data if the data didn't change. As HID tracks events on the
HID level, we haven't done the keycode translation, yet. Therefore, the
'dead' key is tracked independently of the real key, therefore, any events
on it will be ignored.

This patch simply discards any HID events for absolute data if it didn't
change compared to the last report. We need to ignore relative and
buffered-byte reports for obvious reasons. But those cannot be affected by
this bug, so we're fine.

Preferably, we'd do this filtering on the HID-core level. But this might
break a lot of custom drivers, if they do not follow the HID specs.
Therefore, we do this late in hid-input just before we inject it into the
input layer (which does the exact same filtering, but on the keycode
level).

If this turns out to break some devices, we might have to limit filtering
to EV_KEY events. But lets try to do the Right Thing first, and properly
filter any absolute data that didn't change.

This patch is tagged for 'stable' as it fixes a lot of n-key RollOver
hardware. We might wanna wait with backporting for a while, before we know
it doesn't break anything else, though.

Reported-by: Adam Goode 
Reported-by: Fredrik Hallenberg 
Tested-by: Fredrik Hallenberg 
Signed-off-by: David Herrmann 
Signed-off-by: Jiri Kosina 
Signed-off-by: Greg Kroah-Hartman

HID: add battery quirk for USB_DEVICE_ID_APPLE_ALU_WIRELESS_2011_ISO keyboard

2015-01-16T14:59:31+00:00

commit da940db41dcf8c04166f711646df2f35376010aa upstream.

Apple bluetooth wireless keyboard (sold in UK) has always reported zero
for battery strength no matter what condition the batteries are actually
in. With this patch applied (applying same quirk as other Apple
keyboards), the battery strength is now correctly reported.

Signed-off-by: Karl Relton 
Signed-off-by: Jiri Kosina 
Signed-off-by: Greg Kroah-Hartman

HID: fix buffer allocations

2014-02-03T10:02:01+00:00

When using hid_output_report(), the buffer should be allocated by hid_alloc_report_buf(),
not a custom malloc.

Signed-off-by: Benjamin Tissoires 
Signed-off-by: Jiri Kosina

HID: input: fix input sysfs path for hid devices

2013-12-20T22:24:40+00:00

we used to set the parent of the input device as the parent of
the hid bus. This was introduced when we created hid as a real bus, and
to keep backward compatibility. Now, it's time to proper set the parent
so that sysfs has an idea of which input device is attached to
which hid device.

Signed-off-by: Benjamin Tissoires 
David Herrmann 
Signed-off-by: Jiri Kosina

HID: Fix unit exponent parsing again

2013-10-18T13:13:39+00:00

Revert some changes done in 774638386826621c984ab6994439f474709cac5e.

Revert all changes done in hidinput_calc_abs_res as it mistakingly used
"Unit" item exponent nibbles to affect resolution value. This wasn't
breaking resolution calculation of relevant axes of any existing
devices, though, as they have only one dimension to their units and thus
1 in the corresponding nible.

Revert to reading "Unit Exponent" item value as a signed integer in
hid_parser_global to fix reading specification-complying values. This
fixes resolution calculation of devices complying to the HID standard,
including Huion, KYE, Waltop and UC-Logic graphics tablets which have
their report descriptors fixed by the drivers.

Explanations follow.

There are two "unit exponents" in HID specification and it is important
not to mix them. One is the global "Unit Exponent" item and another is
nibble values in the global "Unit" item. See 6.2.2.7 Global Items.

The "Unit Exponent" value is just a signed integer and is used to scale
the integer resolution unit values, so fractions can be expressed.

The nibbles of "Unit" value are used to select the unit system (nibble
0), and presence of a particular basic unit type in the unit formula and
its *exponent* (or power, nibbles 1-6). And yes, the latter is in two
complement and zero means absence of the unit type.

Taking the representation example of (integer) joules from the
specification:

[mass(grams)][length(centimeters)^2][time(seconds)^-2] * 10^-7

the "Unit Exponent" would be -7 (or 0xF9, if stored as a byte) and the
"Unit" value would be 0xE121, signifying:

Nibble  Part        Value   Meaning
-----   ----        -----   -------
0       System      1       SI Linear
1       Length      2       Centimeters^2
2       Mass        1       Grams
3       Time        -2      Seconds^-2

To give the resolution in e.g. hundredth of joules the "Unit Exponent"
item value should have been -9.

See also the examples of "Unit" values for some common units in the same
chapter.

However, there is a common misunderstanding about the "Unit Exponent"
value encoding, where it is assumed to be stored the same as nibbles in
"Unit" item. This is most likely due to the specification being a bit
vague and overloading the term "unit exponent". This also was and still
is proliferated by the official "HID Descriptor Tool", which makes this
mistake and stores "Unit Exponent" as such. This format is also
mentioned in books such as "USB Complete" and in Microsoft's hardware
design guides.

As a result many devices currently on the market use this encoding and
so the driver should support them.

Signed-off-by: Nikolai Kondrashov 
Acked-by: Benjamin Tissoires 
Signed-off-by: Jiri Kosina

HID: validate feature and input report details

2013-09-13T13:13:22+00:00

When dealing with usage_index, be sure to properly use unsigned instead of
int to avoid overflows.

When working on report fields, always validate that their report_counts are
in bounds.
Without this, a HID device could report a malicious feature report that
could trick the driver into a heap overflow:

[  634.885003] usb 1-1: New USB device found, idVendor=0596, idProduct=0500
...
[  676.469629] BUG kmalloc-192 (Tainted: G        W   ): Redzone overwritten

CVE-2013-2897

Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Tissoires 
Acked-by: Kees Cook 
Signed-off-by: Jiri Kosina

Merge branches 'for-3.12/devm', 'for-3.12/i2c-hid', 'for-3.12/i2c-hid-dt', 'for-3.12/logitech', 'for-3.12/multitouch-win8', 'for-3.12/trasnport-driver-cleanup', 'for-3.12/uhid', 'for-3.12/upstream' and 'for-3.12/wiimote' into for-linus

2013-09-06T09:58:37+00:00

HID: battery: don't do DMA from stack

2013-09-02T11:43:00+00:00

Instead of using data from stack for DMA in hidinput_get_battery_property(),
allocate the buffer dynamically.

Cc: stable@kernel.org
Reported-by: Richard Ryniker 
Reported-by: Alan Stern 
Signed-off-by: Jiri Kosina