Re: [PATCH v2, 2/2] media: mediatek: vcodec: make sure pointer isn't NULL before used

From: Irui Wang (王瑞)
Date: Tue Apr 11 2023 - 03:38:39 EST


Dear Yunfei,

Thanks for your reviewing.

On Tue, 2023-04-11 at 07:22 +0000, Yunfei Dong (董云飞) wrote:
> Hi Irui,
>
> On Tue, 2023-04-11 at 13:54 +0800, Irui Wang wrote:
> > CERT-C Expression check:
> > Dereferencing buf, which is known to be NULL, check buf is not NULL
> > before used.
> >
>
> Whether 'dereferencing buf' is one kind of CERT-C Expression check?
> You can re-write commit message and subject.
>
> CERT-C Expression check (Dereferencing buf):
no, 'buf' is the used variable name, this coverity is 'Dereference null
return value(NULL RETURNS)' .
> Making sure the pointer is not NULL before to be used.
>
> Best Regards,
> Yunfei Dong

Thanks
Best Regards
> > Signed-off-by: Irui Wang <irui.wang@xxxxxxxxxxxx>
> > ---
> > drivers/media/platform/mediatek/vcodec/mtk_vcodec_enc.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git
> > a/drivers/media/platform/mediatek/vcodec/mtk_vcodec_enc.c
> > b/drivers/media/platform/mediatek/vcodec/mtk_vcodec_enc.c
> > index d65800a3b89d..db65e77bd373 100644
> > --- a/drivers/media/platform/mediatek/vcodec/mtk_vcodec_enc.c
> > +++ b/drivers/media/platform/mediatek/vcodec/mtk_vcodec_enc.c
> > @@ -943,7 +943,7 @@ static int vb2ops_venc_start_streaming(struct
> > vb2_queue *q, unsigned int count)
> > * FIXME: This check is not needed as only active
> > buffers
> > * can be marked as done.
> > */
> > - if (buf->state == VB2_BUF_STATE_ACTIVE) {
> > + if (buf && buf->state == VB2_BUF_STATE_ACTIVE) {
> > mtk_v4l2_debug(0, "[%d] id=%d, type=%d, %d ->
> > VB2_BUF_STATE_QUEUED",
> > ctx->id, i, q->type,
> > (int)buf->state);