On Tue, 07 Dec 2021 07:29:41 +0100,
Kees Cook wrote:
>
> The mixart_timer_notify structure was larger than could be represented
> by the mixart_msg_data array storage. Adjust the size to as large as
> possible to fix the warning seen with -Warray-bounds builds:
>
> sound/pci/mixart/mixart_core.c: In function 'snd_mixart_threaded_irq':
> sound/pci/mixart/mixart_core.c:447:50: error: array subscript 'struct mixart_timer_notify[0]' is partly outside array bounds of 'u32[128]' {aka 'unsigned int[128]'} [-Werror=array-bounds]
> 447 | for(i=0; i<notify->stream_count; i++) {
> | ^~
> sound/pci/mixart/mixart_core.c:328:12: note: while referencing 'mixart_msg_data'
> 328 | static u32 mixart_msg_data[MSG_DEFAULT_SIZE / 4];
> | ^~~~~~~~~~~~~~~
>
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Thanks, applied now.
> @@ -444,6 +442,7 @@ irqreturn_t snd_mixart_threaded_irq(int irq, void *dev_id)
> struct mixart_timer_notify *notify;
> notify = (struct mixart_timer_notify *)mixart_msg_data;
>
> + BUILD_BUG_ON(sizeof(notify) > sizeof(mixart_msg_data));
> for(i=0; i<notify->stream_count; i++) {
>
> u32 buffer_id = notify->streams[i].buffer_id;
I guess we should add the array boundary check of
notify->stream_count, instead of fully relying on the hardware reply,
too. Will submit the additional check.
Takashi
