Am I going mad or does TDB allow multiple writers to update the freelist?

Richard Sharpe realrichardsharpe at
Tue Jan 20 22:43:14 GMT 2009

On 1/20/09, Volker Lendecke <Volker.Lendecke at> wrote:
> On Tue, Jan 20, 2009 at 02:29:25PM -0800, Richard Sharpe wrote:
>  > OK, now I understand, I think. I assumed that the tdb control
>  > structure was part of the mmaped memory and that they were both
>  > looking at the same memory.
>  >
>  > Hmmm, have to look harder for the tdb freelist corruption I have found, then.
> You're certain that none of the smbds on that box has ever
>  crashed? This might leave the tdb also in a corrupt state.

winbindd_idmap.tdb ...

I dont think so, but will check, I need to check into that. There is
one report of a loop in the freelist, and I have an example of a
corruption in the freelist that looks really weird.

The next pointer for the penultimate entry on the free list points 536
bytes beyond the start of the unallocated area and what should be the
last entry on the free list.

It has the feel of multiple processes messing with the freelist at the
same time.

Richard Sharpe

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