Re: KEYS: trusted: Use common error handling code in trusted_update()

From: SF Markus Elfring
Date: Sat Nov 11 2017 - 04:38:40 EST


> Safe means that cleanup code should appear once in a cascade at the end
> of the function, to minimize the chance that anything will be overlooked.

I find that the control flow of this function implementation does not fit
to the mentioned ideal so far.


> Moving the ret assignments to the end of the function and adding the
> backward jumps doesn't make the code more understandable.

Is this structure required if you would like to achieve something
in the shown software design direction?


> On the other hand, moving the kzalloc of new_p to the end of the function
> could be helpful,

Why do you think that the movement of this function call can finally work
in the concrete software situation?


> because it reduces the chance that new error handling code,
> if any turns out to be needed, will forget this operation.

Your expectation can be nice.


> By why not just follow standard practice and free the structures in a
> cascade in the inverse of the order in which they are allocated at the end
> of the function?

This is still happening here partly, isn't it?


> There can be a descriptive label for each thing that needs to be freed.

Which identifiers would you find more appropriate in comparison to
my suggestion?

* e_inval
* e_nomem
* free_data
* free_payload

Regards,
Markus