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From b96c60f55789527b1f9232ddae03e5c7566bf578 Mon Sep 17 00:00:00 2001
From: Sumit Bose <sbose@redhat.com>
Date: Fri, 4 May 2018 17:00:55 +0200
Subject: [PATCH] NSS: nss_clear_netgroup_hash_table() do not free data
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nss_clear_netgroup_hash_table() is called during the clearEnumCache SBUS
request, which is e.g. used during 'sss_cache -E', to remove netgroup
data cached in the memory of the NSS responder.

Currently nss_clear_netgroup_hash_table() calls
'sss_ptr_hash_delete_all(nss_ctx->netgrent, true);' which not only
removes all entries in the 'netgerent' hash table but frees them as
well.

The second step is not needed because nss_setnetgrent_set_timeout()
takes care that the data is freed after a timeout. Additionally freeing
the data in nss_clear_netgroup_hash_table() can even do harm when the
request is received by the NSS responder while waiting for the backend
to acquire the netgroup data. Because if the backend is done the NSS
responder tries do use enum_ctx which might have been freed in the
meantime.

Because of this nss_clear_netgroup_hash_table() should only remove the
data from the hash table but not free it.

Related to https://pagure.io/SSSD/sssd/issue/3731

Reviewed-by: Pavel Březina <pbrezina@redhat.com>
(cherry picked from commit b13cc2d1413a0d5bbe36e06e5ffd87dbf5c0cb9f)
---
 src/responder/nss/nsssrv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/responder/nss/nsssrv.c b/src/responder/nss/nsssrv.c
index 171c2a5ca..004e6c1a1 100644
--- a/src/responder/nss/nsssrv.c
+++ b/src/responder/nss/nsssrv.c
@@ -142,7 +142,7 @@ static int nss_clear_netgroup_hash_table(struct sbus_request *dbus_req, void *da
 
     DEBUG(SSSDBG_TRACE_FUNC, "Invalidating netgroup hash table\n");
 
-    sss_ptr_hash_delete_all(nss_ctx->netgrent, true);
+    sss_ptr_hash_delete_all(nss_ctx->netgrent, false);
 
     return sbus_request_return_and_finish(dbus_req, DBUS_TYPE_INVALID);
 }
-- 
2.17.0