Ticket #47649 - Server hangs in cos_cache when adding a user entry

Bug description: cos_dn_defs_cb reads cosDefinition and sets up the cos
Definition part of cos cache.  In the function, when processing
cosAttribute, cosTargetTree and cosTemlpateDn are missing, it sets the
parent dn of the cos definition dn.  This parent setting is needed only
when the 2 attributes are completely missing from the cos definition.
But if the attributes are located below cosAttribute (see the Example
cos definition), in addition to "cn=cosTemplates,ou=people,dc=example,
dc=com", the parent of "cn=generatePostalCode,ou=People,dc=example,dc=com"
is added to the cos cache as cosTemplateDn.
  Example cos definition:
    dn: cn=generatePostalCode,ou=People,dc=example,dc=com
    description: generate postalCode attr based on location
    objectClass: top
    objectClass: ldapsubentry
    objectClass: cossuperdefinition
    objectClass: cosClassicDefinition
    cosAttribute: postalCode
    costemplatedn: cn=cosTemplates,ou=people,dc=example,dc=com
    cosSpecifier: l
    cn: generatePostalCode
The mistakenly added cosTemplatedDn makes adding an entry under ou=People
notify recreating the cos cache.  The notification needs to be outside of
backend transaction since it causes a deadlock with the cos_cache_wait_
on_change thread which cannot read the DB due to the transaction but holds
the lock that the notifier thread is waiting for.

Fix description: The parent of the cos definition dn is set to the
cosTargetTree and the cosTemlpateDn, only when the attributes are
completely missing.

https://fedorahosted.org/389/ticket/47649

Reviewed by [email protected] (Thank you, Rich!!)

ldap/servers/plugins/cos/cos_cache.c

@@ -727,7 +727,8 @@ struct dn_defs_info {
  * if a particular attempt to add a definition fails: info.ret gets set to
  * zero only if we succed to add a def.
 */
-static int 	cos_dn_defs_cb (Slapi_Entry* e, void *callback_data)
+static int 
+cos_dn_defs_cb (Slapi_Entry* e, void *callback_data)
 {
 	struct dn_defs_info *info;
 	cosAttrValue **pSneakyVal = 0;
@@ -877,31 +878,10 @@ static int 	cos_dn_defs_cb (Slapi_Entry* e, void *callback_data)
 					                      dnVals[valIndex]->bv_val);
 				}
 
-				if(!pCosTargetTree)
-				{
-					/* get the parent of the definition */
-					char *orig = slapi_dn_parent(pDn->val);
-					Slapi_DN *psdn = slapi_sdn_new_dn_byval(orig);
-					char *parent = (char *)slapi_sdn_get_dn(psdn);
-					if (!parent) {
-						parent = (char *)slapi_sdn_get_udn(psdn);
-						LDAPDebug(LDAP_DEBUG_ANY, 
-						  "cos_cache_build_definition_list: "
-						  "failed to normalize parent dn %s. "
-						  "Adding the pre normalized dn.\n", 
-						  parent, 0, 0);
-					}
-					cos_cache_add_attrval(&pCosTargetTree, parent);
-					if (!pCosTemplateDn) {
-						cos_cache_add_attrval(&pCosTemplateDn, parent);
-					}
-					slapi_sdn_free(&psdn);
-				}
-				
 				slapi_vattrspi_regattr((vattr_sp_handle *)vattr_handle,
 				                        dnVals[valIndex]->bv_val, NULL, NULL);
 			} /* if(attrType is cosAttribute) */
-										
+
 			/*
 			 * Add the attributetype to the appropriate
 			 * list.
@@ -913,6 +893,47 @@ static int 	cos_dn_defs_cb (Slapi_Entry* e, void *callback_data)
 		ber_bvecfree( dnVals );
 		dnVals = NULL;
 	} while(!slapi_entry_next_attr(e, dnAttr, &dnAttr));
+
+	if (pCosAttribute && (!pCosTargetTree || !pCosTemplateDn)) {
+		/* get the parent of the definition */
+		char *orig = slapi_dn_parent(pDn->val);
+		char *parent = NULL;
+		if (orig) {
+			parent = slapi_create_dn_string("%s", orig);
+			if (!parent) {
+				parent = orig;
+				LDAPDebug1Arg(LDAP_DEBUG_ANY, 
+				              "cos_dn_defs_cb: "
+				              "failed to normalize parent dn %s. "
+				              "Adding the pre normalized dn.\n", 
+				              parent);
+			}
+			if (!pCosTargetTree) {
+				cos_cache_add_attrval(&pCosTargetTree, parent);
+			}
+			if (!pCosTemplateDn) {
+				cos_cache_add_attrval(&pCosTemplateDn, parent);
+			}
+			if (parent != orig) {
+				slapi_ch_free_string(&parent);
+			}
+			slapi_ch_free_string(&orig);
+		} else {
+			LDAPDebug1Arg(LDAP_DEBUG_ANY, 
+			              "cos_dn_defs_cb: "
+			              "failed to get parent dn of cos definition %s.\n",
+			              pDn->val);
+			if (!pCosTemplateDn) {
+				if (!pCosTargetTree) {
+					LDAPDebug0Args(LDAP_DEBUG_ANY, "cosTargetTree and cosTemplateDn are not set.\n");
+				} else {
+					LDAPDebug0Args(LDAP_DEBUG_ANY, "cosTemplateDn is not set.\n");
+				}
+			} else if (!pCosTargetTree) {
+				LDAPDebug0Args(LDAP_DEBUG_ANY, "cosTargetTree is not set.\n");
+			}
+		}
+	}
 	
 	/*
 	determine the type of class of service scheme 
@@ -951,9 +972,7 @@ static int 	cos_dn_defs_cb (Slapi_Entry* e, void *callback_data)
 	*/
 	
 	/* these must exist */
-	if(		pDn &&
-		pObjectclass && 
-		
+	if(pDn && pObjectclass && 
 		(
 		(cosType == COSTYPE_CLASSIC &&
 		pCosTemplateDn && 
@@ -3582,14 +3601,9 @@ static int cos_cache_entry_is_cos_related( Slapi_Entry *e) {
 			{
 				pObj = (char*)slapi_value_get_string(val);
 
-				/*
-				 * objectclasses are ascii--maybe strcasecmp() is faster than
-				 * slapi_utf8casecmp()
-				*/
-				if(	!strcasecmp(pObj, "cosdefinition") ||
-					!strcasecmp(pObj, "cossuperdefinition") ||
-					!strcasecmp(pObj, "costemplate")
-					)
+				if(!strcasecmp(pObj, "cosdefinition") ||
+				   !strcasecmp(pObj, "cossuperdefinition") ||
+				   !strcasecmp(pObj, "costemplate"))
 				{
 					rc = 1;
 				}