Re: [PATCH] hw/display/xenfb: Replace unreachable code by abort()

[Bernhard Beschow <shentey@xxxxxxxxx>]

Am 13. Oktober 2025 11:10:45 UTC schrieb Markus Armbruster <armbru@xxxxxxxxxx>:
>Ping?
>
>Markus Armbruster <armbru@xxxxxxxxxx> writes:
>
>> xenfb_mouse_event() has a switch statement whose controlling
>> expression move->axis is an enum InputAxis.  The enum values are
>> INPUT_AXIS_X and INPUT_AXIS_Y, encoded as 0 and 1.  The switch has a
>> case for both axes.  In addition, it has an unreachable default label.
>> This convinces Coverity that move->axis can be greater than 1.  It
>> duly reports a buffer overrun when it is used to subscript an array
>> with two elements.
>>
>> Replace the unreachable code by abort().
>>
>> Resolves: Coverity CID 1613906
>> Signed-off-by: Markus Armbruster <armbru@xxxxxxxxxx>
>> ---
>>  hw/display/xenfb.c | 3 +--
>>  1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
>> index 22822fecea..5e6c691779 100644
>> --- a/hw/display/xenfb.c
>> +++ b/hw/display/xenfb.c
>> @@ -283,8 +283,7 @@ static void xenfb_mouse_event(DeviceState *dev, 
>> QemuConsole *src,
>>                  scale = surface_height(surface) - 1;
>>                  break;
>>              default:
>> -                scale = 0x8000;
>> -                break;
>> +                abort();

Don't we prefer g_assert_not_reached() these days, for more expressiveness?

Best regards,
Bernhard

>>              }
>>              xenfb->axis[move->axis] = move->value * scale / 0x7fff;
>>          }
>
>