[Samba] Samba-LDAP with 100%CPU with connections in CLOSE_WAIT

[Jeremy Allison]

On Mon, Sep 19, 2022 at 05:20:04PM +0200, Steffen via samba wrote:
>Hi,
>
>since some time we are facing a small problem:
>
>
>We are using samba (4.15.9-15) as AD-DC. As clients we have some NetAPP-FAS running which doing the auth. via LDAP. On NetApp timeouts for LDAP are set to 3sec per default.
>
>Some queries seem to need more time to answer so the client tries to close the connection but the (samba-)server-part leaves the socket open in CLOSE_WAIT.
>
>In some of such cases the corresponding process (ldap-worker) runs forever(?) with 100% cpu. A strace shows the ldap-worker pushing some info (the answer?)  to the socket. If one let it go the server slows down gradually while more and more connections stay in CLOSE_WAIT.

Can you post an strace, followed by a stack backtrace
from gdb of an ldap-worker process in such a state.

That would help debug - thanks !