void tsc210x_set_transform(uWireSlave *chip,
                MouseTransformInfo *info)
{
    TSC210xState *s = (TSC210xState *) chip->opaque;
#if 0
    int64_t ltr[8];

    ltr[0] = (int64_t) info->a[1] * info->y;
    ltr[1] = (int64_t) info->a[4] * info->x;
    ltr[2] = (int64_t) info->a[1] * info->a[3] -
            (int64_t) info->a[4] * info->a[0];
    ltr[3] = (int64_t) info->a[2] * info->a[4] -
            (int64_t) info->a[5] * info->a[1];
    ltr[4] = (int64_t) info->a[0] * info->y;
    ltr[5] = (int64_t) info->a[3] * info->x;
    ltr[6] = (int64_t) info->a[4] * info->a[0] -
            (int64_t) info->a[1] * info->a[3];
    ltr[7] = (int64_t) info->a[2] * info->a[3] -
            (int64_t) info->a[5] * info->a[0];

    /* Avoid integer overflow */
    s->tr[0] = ltr[0] >> 11;
    s->tr[1] = ltr[1] >> 11;
    s->tr[2] = muldiv64(ltr[2], 1, info->a[6]);
    s->tr[3] = muldiv64(ltr[3], 1 << 4, ltr[2]);
    s->tr[4] = ltr[4] >> 11;
    s->tr[5] = ltr[5] >> 11;
    s->tr[6] = muldiv64(ltr[6], 1, info->a[6]);
    s->tr[7] = muldiv64(ltr[7], 1 << 4, ltr[6]);
#else

    /* This version assumes touchscreen X & Y axis are parallel or
     * perpendicular to LCD's  X & Y axis in some way.  */
    if (abs(info->a[0]) > abs(info->a[1])) {
        s->tr[0] = 0;
        s->tr[1] = -info->a[6] * info->x;
        s->tr[2] = info->a[0];
        s->tr[3] = -info->a[2] / info->a[0];
        s->tr[4] = info->a[6] * info->y;
        s->tr[5] = 0;
        s->tr[6] = info->a[4];
        s->tr[7] = -info->a[5] / info->a[4];
    } else {
        s->tr[0] = info->a[6] * info->y;
        s->tr[1] = 0;
        s->tr[2] = info->a[1];
        s->tr[3] = -info->a[2] / info->a[1];
        s->tr[4] = 0;
        s->tr[5] = -info->a[6] * info->x;
        s->tr[6] = info->a[3];
        s->tr[7] = -info->a[5] / info->a[3];
    }

    s->tr[0] >>= 11;
    s->tr[1] >>= 11;
    s->tr[3] <<= 4;
    s->tr[4] >>= 11;
    s->tr[5] >>= 11;
    s->tr[7] <<= 4;
#endif
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.