[Samba] Missing Files/Missing Folders from an NFS Share

[Jeremy Allison]

On Mon, Feb 27, 2023 at 08:01:40PM +0100, Conor Armstrong wrote:
>   I think it has a lot to do with telldir on an NFS share returning a cookie
>   that is supposed to be unique rather than an actual offset. Problem is,
>   that cookie is stored as a 31bit hash which can then end up as a negative
>   signed offset in Samba which is not handled correctly. The cookies are not
>   necessarily consecutive as you move through a directory.  

We only store the returned cookie as a 'long' from telldir(), and then use
it to get to the same position again via seekdir(). There isn't any
interpretation of the actual value inside Samba other than 3 'magic'
values we use #defined here:

/* "Special" directory offsets. */
#define END_OF_DIRECTORY_OFFSET ((long)-1)
#define START_OF_DIRECTORY_OFFSET ((long)0)
#define DOT_DOT_DIRECTORY_OFFSET ((long)0x80000000)

So long as telldir() doesn't return any of these,
we should work fine. We don't expect the cookies
to be consecutive or in any order for that matter.

So I would take issue with your statement:

"can then end up as a negative signed offset in Samba which is not handled correctly"

:-).