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.

1 files changed, 4 insertions, 4 deletions

diff --git a/source/passdb/lookup_sid.c b/source/passdb/lookup_sid.c
index dbc0e75e595..dd7ffa8d819 100644
--- a/source/passdb/lookup_sid.c
+++ b/source/passdb/lookup_sid.c
@@ -102,7 +102,7 @@ BOOL lookup_name(TALLOC_CTX *mem_ctx,
 			goto ok;
 	}
 
-	if (strequal(domain, unix_users_domain_name())) {
+	if (!(flags & LOOKUP_NAME_EXPLICIT) && strequal(domain, unix_users_domain_name())) {
 		if (lookup_unix_user_name(name, &sid)) {
 			type = SID_NAME_USER;
 			goto ok;
@@ -111,7 +111,7 @@ BOOL lookup_name(TALLOC_CTX *mem_ctx,
 		return False;
 	}
 
-	if (strequal(domain, unix_groups_domain_name())) {
+	if (!(flags & LOOKUP_NAME_EXPLICIT) && strequal(domain, unix_groups_domain_name())) {
 		if (lookup_unix_group_name(name, &sid)) {
 			type = SID_NAME_DOM_GRP;
 			goto ok;
@@ -262,13 +262,13 @@ BOOL lookup_name(TALLOC_CTX *mem_ctx,
 	/* 11. Ok, windows would end here. Samba has two more options:
                Unmapped users and unmapped groups */
 
-	if (lookup_unix_user_name(name, &sid)) {
+	if (!(flags & LOOKUP_NAME_EXPLICIT) && lookup_unix_user_name(name, &sid)) {
 		domain = talloc_strdup(tmp_ctx, unix_users_domain_name());
 		type = SID_NAME_USER;
 		goto ok;
 	}
 
-	if (lookup_unix_group_name(name, &sid)) {
+	if (!(flags & LOOKUP_NAME_EXPLICIT) && lookup_unix_group_name(name, &sid)) {
 		domain = talloc_strdup(tmp_ctx, unix_groups_domain_name());
 		type = SID_NAME_DOM_GRP;
 		goto ok;