On Mon, May 28, 2018 at 07:03:05AM -0300, Mauro Carvalho Chehab wrote:
> I can't see how brx can be NULL. At the sequence of ifs:
>
> if (pipe->num_inputs > 2)
> brx = &vsp1->bru->entity;
> else if (pipe->brx && !drm_pipe->force_brx_release)
> brx = pipe->brx;
> else if (!vsp1->bru->entity.pipe)
> brx = &vsp1->bru->entity;
> else
> brx = &vsp1->brs->entity;
>
>
> The usage of brx = &(something) will always return a non NULL
> value[1].
That's not right. It can be NULL if it's &foo->first_struct_member
and ->entity is the first struct member. If it weren't the first struct
member then Smatch would say that brx was non-NULL.
> [1] It might be doing a NULL deref - with seems to be your concern
> when you're talking about the case where vsp1->brs is NULL - but
> that's not what Smatch is complaining here.
If vsp1->bru were NULL, it wouldn't be a NULL dereference because it's
not dereferencing it; it's just taking the address. On the path where
we do:
else if (!vsp1->bru->entity.pipe)
brx = &vsp1->bru->entity;
Then Smatch sees that vsp1->bru is dereferenced and marks "brx" as
non-NULL.
regards,
dan carpenter
