Re: Office 2007 MSI Crash - Null dereference @ MsiViewExecute

[Mike Kaplinskiy]

On Sun, May 3, 2009 at 10:36 PM, James Hawkins <truiken(a)gmail.com> wrote:
> On Sun, May 3, 2009 at 1:52 PM, Mike Kaplinskiy
> <mike.kaplinskiy(a)gmail.com> wrote:
> > On Thu, Apr 30, 2009 at 1:08 PM, James Hawkins <truiken(a)gmail.com> wrote:
> > > On Thu, Apr 30, 2009 at 4:03 AM, Austin English <austinenglish(a)gmail.com> wrote:
> > > > On Tue, Apr 28, 2009 at 9:27 PM, Mike Kaplinskiy
> > > > <mike.kaplinskiy(a)gmail.com> wrote:
> > > > > I was looking at the trace of the crash from bug 17600, and it looks like
> > > > > a custom action is calling MsiViewExecute with a null hRec.
> > > > >
> > > > > I (sadly) don't know much about the wine MSI architecture, but the
> > > > > msiobj_lock on line 484 should fail since rec will never be fetched
> > > > > (null). I think the intention was to make it query->hdr (as it is
> > > > > released later).
> > > >
> > > > A testcase for it would show if you're right or wrong ;-).
> > >
> > > Not really.  If you grep through the msi tests, you'll see that we
> > > call MsiViewExecute with NULL hRec all over the place.  That doesn't
> > > mean there isn't a bug, just saying.
> > >
> > > --
> > > James Hawkins
> >
> > So I got a little time to look into this, and was completely blown
> > away. Apparently doing
> >
> > TRACE("dereferencing 0?=%p\n", (void *) &(((MSIRECORD *) NULL)->hdr));
> >
> > works, since nothing ever gets dereferenced. I will post a patch for
> > this small nit.
> >
> > On a slightly different note, I have traced the problem in office 2007
> > to the patch by James, and in particular to INSERT_execute. The row
> > index gets set to 0 if the primary key is null (which is what office
> > install is doing), but if the insert is temporary TABLE_insert assumes
> > that row >= tv->table->row_count, and subtracts from the row index,
> > putting us in the negatives (or high positives due to uint).
> >
> > I have a patch for this, but I don't know how to make a testcase (all
> > I know is office installs), so would anyone mind pointing me to
> > somewhere that explains msi temporary inserts?
> >
> > And should I post the patch up on wine-patches to get it critiqued?
> > (sorry, first time)
>
> I'll take a look at your patch.  No offense intended, but it's
> probably not correct.  The problem is a beast and deeply rooted in the
> way we store temporary rows in the DB.  I have a huge test patch for
> it, and I had a fix, but my linux HD got fragged (bummer).
>
> --
> James Hawkins

(Sorry, forgot to forward to the list)

Thanks James. I'm not gonna post it on the patches list quiet yet
then. I checked that the msi tests pass with the patch as well.

Mike.