Arkadiusz Hiler : hidclass.sys: Calculate correct bitCount for vendor-specific 1 bit repeated elements.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 5a32339dc858d898ac2fa1c948306a2ec271c68b
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=5a32339dc858d898ac2fa1c94...

Author: Arkadiusz Hiler <ahiler(a)codeweavers.com>
Date:   Thu Jan 21 18:11:13 2021 +0200

hidclass.sys: Calculate correct bitCount for vendor-specific 1 bit repeated elements.

DualSense controller's report descriptor comes with a 1 bit vendor specific
(Usage Page & Usage) element repeated through 'report count'.

Those were correctly interpreted as non-ranged buttons (exposed as button caps
with appropriate usage values) but their size was incorrectly assumed to be 1
ignoring the 'report count'.

Because of that the InputReportByteLength is miscalculated as 63 instead of
64. If the buffer passed to HidD_GetInputReport() is allocated using that
value the call will fail with ERROR_INSUFFICIENT_BUFFER.

This change fixes the above and cleans up the code a bit so the size for each
case is calculated directly from the count and size instead of using the
values that were derived from them.

Signed-off-by: Arkadiusz Hiler <ahiler(a)codeweavers.com>
Signed-off-by: Aric Stewart <aric(a)codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard(a)winehq.org>

---

 dlls/hidclass.sys/descriptor.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/dlls/hidclass.sys/descriptor.c b/dlls/hidclass.sys/descriptor.c
index 56e4da4ad10..c02988494fd 100644
--- a/dlls/hidclass.sys/descriptor.c
+++ b/dlls/hidclass.sys/descriptor.c
@@ -698,6 +698,10 @@ static void build_elements(WINE_HID_REPORT *wine_report, WINE_HID_ELEMENT *elems
     }
 
     wine_element->valueStartBit = wine_report->bitSize;
+
+    wine_element->bitCount = (feature->caps.BitSize * feature->caps.ReportCount);
+    wine_report->bitSize += wine_element->bitCount;
+
     if (feature->caps.BitSize == 1)
     {
         wine_element->ElementType = ButtonElement;
@@ -713,8 +717,6 @@ static void build_elements(WINE_HID_REPORT *wine_report, WINE_HID_ELEMENT *elems
         wine_element->caps.button.IsAbsolute = feature->IsAbsolute;
         if (wine_element->caps.button.IsRange)
         {
-            wine_element->bitCount = (feature->caps.u.Range.UsageMax - feature->caps.u.Range.UsageMin) + 1;
-            wine_report->bitSize += wine_element->bitCount;
             wine_element->caps.button.u.Range.UsageMin = feature->caps.u.Range.UsageMin;
             wine_element->caps.button.u.Range.UsageMax = feature->caps.u.Range.UsageMax;
             wine_element->caps.button.u.Range.StringMin = feature->caps.u.Range.StringMin;
@@ -727,8 +729,6 @@ static void build_elements(WINE_HID_REPORT *wine_report, WINE_HID_ELEMENT *elems
         }
         else
         {
-            wine_report->bitSize++;
-            wine_element->bitCount = 1;
             wine_element->caps.button.u.NotRange.Usage = feature->caps.u.NotRange.Usage;
             wine_element->caps.button.u.NotRange.Reserved1 = feature->caps.u.NotRange.Usage;
             wine_element->caps.button.u.NotRange.StringIndex = feature->caps.u.NotRange.StringIndex;
@@ -756,8 +756,6 @@ static void build_elements(WINE_HID_REPORT *wine_report, WINE_HID_ELEMENT *elems
         wine_element->caps.value.HasNull = feature->HasNull;
         wine_element->caps.value.BitSize = feature->caps.BitSize;
         wine_element->caps.value.ReportCount = feature->caps.ReportCount;
-        wine_element->bitCount = (feature->caps.BitSize * wine_element->caps.value.ReportCount);
-        wine_report->bitSize += wine_element->bitCount;
         wine_element->caps.value.UnitsExp = feature->caps.UnitsExp;
         wine_element->caps.value.Units = feature->caps.Units;
         wine_element->caps.value.LogicalMin = feature->caps.LogicalMin;