Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit fd3718c0 authored by Siarhei Vishniakou's avatar Siarhei Vishniakou
Browse files

Initialize PointerCoords in input tests 

The struct PointerCoords in VelocityTracker_test is created on the
stack, but never initialized. Later, the coords are used to add an x and
y value to the MotionEvent.

The field "bits" in the struct is therefore initialized to whatever was
previously occupying that stack address.
It is possible that stack contained some non-zero data. This would cause
enough of the bits of the 'bits' variable to be set, but without any of
them being X or Y. As a result, when a new X or Y value is assigned, it
does not fit into the bits (there's a 30-axes limit), and therefore
remains at zero.

Later, when velocity is computed, the coordinates evaluate to zero, and
therefore, zero velocity is produced. The test fails, because a non-zero
velocity is expected.

After an audit of the entire Android codebase for usage of
PointerCoords, found another potential issue in InputClassifier_test.
Likely the code was copied over from VelocityTracker_test. Add a fix for
that as well.

Bug: 126536349
Test: atest -it -a libinput_tests, but only executed after building and
flashing asanified libinput and libinput_tests onto device.

Change-Id: Id8b870b6201d7489284bf9fc646750770bb9321a
parent c086504b

libs/input/tests/VelocityTracker_test.cpp

+1 −0
Original line number Diff line number Diff line
@@ -90,6 +90,7 @@ MotionEvent* createSimpleMotionEvent(const Position* positions, size_t numSample 


    MotionEvent* event = new MotionEvent();

    PointerCoords coords;

    coords.clear();

    constexpr size_t pointerCount = 1;

    PointerProperties properties[pointerCount];

services/inputflinger/tests/InputClassifier_test.cpp

+9 −9
Original line number Diff line number Diff line
@@ -29,20 +29,20 @@ namespace android { 


static NotifyMotionArgs generateBasicMotionArgs() {

    // Create a basic motion event for testing

    constexpr size_t pointerCount = 1;

    PointerProperties properties[pointerCount];

    properties[0].id = 0;

    properties[0].toolType = AMOTION_EVENT_TOOL_TYPE_FINGER;



    PointerCoords coords[pointerCount];

    coords[0].setAxisValue(AMOTION_EVENT_AXIS_X, 1);

    coords[0].setAxisValue(AMOTION_EVENT_AXIS_Y, 1);

    PointerProperties properties;

    properties.id = 0;

    properties.toolType = AMOTION_EVENT_TOOL_TYPE_FINGER;



    PointerCoords coords;

    coords.clear();

    coords.setAxisValue(AMOTION_EVENT_AXIS_X, 1);

    coords.setAxisValue(AMOTION_EVENT_AXIS_Y, 1);

    static constexpr nsecs_t downTime = 2;

    NotifyMotionArgs motionArgs(1/*sequenceNum*/, downTime/*eventTime*/, 3/*deviceId*/,

            AINPUT_SOURCE_ANY, ADISPLAY_ID_DEFAULT, 4/*policyFlags*/, AMOTION_EVENT_ACTION_DOWN,

            0/*actionButton*/, 0/*flags*/, AMETA_NONE, 0/*buttonState*/, MotionClassification::NONE,

            AMOTION_EVENT_EDGE_FLAG_NONE, 5/*deviceTimestamp*/,

            0/*pointerCount*/, properties, coords, 0/*xPrecision*/, 0/*yPrecision*/,

            1/*pointerCount*/, &properties, &coords, 0/*xPrecision*/, 0/*yPrecision*/,

            downTime, {}/*videoFrames*/);

    return motionArgs;

}