r23244: Fix loop with nscd and NSS recusive calls.

> Here's the problem I hit:
>
> getgrnam("foo") -> nscd -> NSS -> winbindd ->
>   winbindd_passdb.c:nam_to_sid() -> lookup_global_sam_name() ->
>   getgrnam("foo") -> nscd -> ....
>
> This is in the SAMBA_3_0 specifically but in theory could happen
> SAMBA_3_0_25 (or 26) for an unknown group.
>
> The attached patch passes down enough state for the
> name_to_sid() call to be able to determine the originating
> winbindd cmd that came into the parent.  So we can avoid
> making more NSS calls if the original call came in trough NSS
> so we don't deadlock ?  But you should still service
> lookupname() calls which are needed for example when
> doing the token access checks for a "valid groups" from
> smb.conf.
>
> I've got this in testing now.  The problem has shown up with the
> DsProvider on OS X and with nscd on SOlaris and Linux.
(This used to be commit bcc8a3290aaa0d2620e9d391ffbbf65541f6d742)

1 files changed, 2 insertions, 0 deletions

diff --git a/source3/nsswitch/winbindd_nss.h b/source3/nsswitch/winbindd_nss.h
index 96c4b1161c..746b98bf79 100644
--- a/source3/nsswitch/winbindd_nss.h
+++ b/source3/nsswitch/winbindd_nss.h
@@ -230,6 +230,8 @@ typedef struct winbindd_gr {
 struct winbindd_request {
 	uint32 length;
 	enum winbindd_cmd cmd;   /* Winbindd command to execute */
+	enum winbindd_cmd original_cmd;   /* Original Winbindd command
+					     issued to parent process */
 	pid_t pid;               /* pid of calling process */
 	uint32 flags;            /* flags relavant to a given request */
 	fstring domain_name;	/* name of domain for which the request applies */