Re: [PATCH] tools/xenstored: Don't crash xenstored when Live-Update is cancelled

[Juergen Gross <jgross@xxxxxxxx>]

On 22.06.21 10:53, Julien Grall wrote:
> Hi Juergen,
>
> On 22/06/2021 10:46, Juergen Gross wrote:
> > On 17.06.21 19:38, Julien Grall wrote:
> > > From: Julien GralL <jgrall@xxxxxxxxxx>
> > >
> > > As Live-Update is asynchronous, it is possible to receive a request to
> > > cancel it (either on the same connection or from a different one).
> > >
> > > Currently, this will crash xenstored because do_lu_start() assumes
> > > lu_status will be valid. This is not the case when Live-Update has been
> > > cancelled. This will result to dereference a NULL pointer and
> > > crash Xenstored.
> > Umm, you introduced that bug in "[PATCH 03/10] tools/xenstore: Don't
> > assume conn->in points to the LU request".
> No. I did reproduced this one without my series. If there are in-flight 
> transaction this will crash in lu_check_lu_allowed() otherwise, it will 
> crash when calling lu_dump_state().
Oh, right, I missed the indirection via delay_request().

Sorry.


Juergen

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