Re: patch2: del/get byid

[jamal <hadi@xxxxxxxxxx>]

On Sat, 2005-30-04 at 10:12 +1000, Herbert Xu wrote:
> On Fri, Apr 29, 2005 at 08:01:21PM -0400, jamal wrote:

> > the policy_kill is?
> 
> 1) You find delpol using xfrm_policy_byid/xfrm_policy_bysel.

Which increments the refcnt

> 2) The timer kicks in and unlinks delpol from the list.

How does this happen again? One path i see is an expiry of delpol about
the same time. 

> 3) You take the list lock and continue to use delpol as if it was
>    still on the list.

I am assuming the refcount is sufficient to protect it.

> 4) You call xfrm_policy_kill on delpol again even though it's already
>    dead.

It can only be dead if ->dead is set and refcnt hits zero, no?

>  
> > > This is also getting pretty hairy for something that nobody has needed so
> > > far.  Which user-space application is going to use this index thing?
> > 
> > did you see the attachment i put with ip x tests?
> 
> Well I meant a usage other than a test suite :)

surely ip is a user space application. Correctness is also valuable
regardless of whether theres an app using it today or not.

cheers,
jamal