]> granicus.if.org Git - postgresql/commitdiff
Fix column-privilege leak in error-message paths
authorStephen Frost <sfrost@snowman.net>
Mon, 12 Jan 2015 22:04:11 +0000 (17:04 -0500)
committerStephen Frost <sfrost@snowman.net>
Wed, 28 Jan 2015 17:33:29 +0000 (12:33 -0500)
While building error messages to return to the user,
BuildIndexValueDescription and ri_ReportViolation would happily include
the entire key or entire row in the result returned to the user, even if
the user didn't have access to view all of the columns being included.

Instead, include only those columns which the user is providing or which
the user has select rights on.  If the user does not have any rights
to view the table or any of the columns involved then no detail is
provided and a NULL value is returned from BuildIndexValueDescription.
Note that, for key cases, the user must have access to all of the
columns for the key to be shown; a partial key will not be returned.

Back-patch all the way, as column-level privileges are now in all
supported versions.

This has been assigned CVE-2014-8161, but since the issue and the patch
have already been publicized on pgsql-hackers, there's no point in trying
to hide this commit.

src/backend/access/index/genam.c
src/backend/access/nbtree/nbtinsert.c
src/backend/commands/copy.c
src/backend/commands/trigger.c
src/backend/executor/execMain.c
src/backend/executor/execUtils.c
src/backend/utils/adt/ri_triggers.c
src/backend/utils/sort/tuplesort.c
src/test/regress/expected/privileges.out
src/test/regress/sql/privileges.sql

index c926ff4654165b90a8bd8037a9e4af51f7ce3b18..9a8e81aab70fc5c390a78e4f01ba1fa206b1e5e9 100644 (file)
 #include "miscadmin.h"
 #include "pgstat.h"
 #include "storage/bufmgr.h"
+#include "utils/acl.h"
 #include "utils/builtins.h"
 #include "utils/lsyscache.h"
 #include "utils/rel.h"
+#include "utils/syscache.h"
 #include "utils/tqual.h"
 
 
@@ -151,6 +153,11 @@ IndexScanEnd(IndexScanDesc scan)
  * form "(key_name, ...)=(key_value, ...)".  This is currently used
  * for building unique-constraint and exclusion-constraint error messages.
  *
+ * Note that if the user does not have permissions to view all of the
+ * columns involved then a NULL is returned.  Returning a partial key seems
+ * unlikely to be useful and we have no way to know which of the columns the
+ * user provided.
+ *
  * The passed-in values/nulls arrays are the "raw" input to the index AM,
  * e.g. results of FormIndexDatum --- this is not necessarily what is stored
  * in the index, but it's what the user perceives to be stored.
@@ -160,13 +167,62 @@ BuildIndexValueDescription(Relation indexRelation,
                                                   Datum *values, bool *isnull)
 {
        StringInfoData buf;
+       Form_pg_index idxrec;
+       HeapTuple       ht_idx;
        int                     natts = indexRelation->rd_rel->relnatts;
        int                     i;
+       int                     keyno;
+       Oid                     indexrelid = RelationGetRelid(indexRelation);
+       Oid                     indrelid;
+       AclResult       aclresult;
+
+       /*
+        * Check permissions- if the user does not have access to view all of the
+        * key columns then return NULL to avoid leaking data.
+        *
+        * First we need to check table-level SELECT access and then, if
+        * there is no access there, check column-level permissions.
+        */
+
+       /*
+        * Fetch the pg_index tuple by the Oid of the index
+        */
+       ht_idx = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexrelid));
+       if (!HeapTupleIsValid(ht_idx))
+               elog(ERROR, "cache lookup failed for index %u", indexrelid);
+       idxrec = (Form_pg_index) GETSTRUCT(ht_idx);
+
+       indrelid = idxrec->indrelid;
+       Assert(indexrelid == idxrec->indexrelid);
+
+       /* Table-level SELECT is enough, if the user has it */
+       aclresult = pg_class_aclcheck(indrelid, GetUserId(), ACL_SELECT);
+       if (aclresult != ACLCHECK_OK)
+       {
+               /*
+                * No table-level access, so step through the columns in the
+                * index and make sure the user has SELECT rights on all of them.
+                */
+               for (keyno = 0; keyno < idxrec->indnatts; keyno++)
+               {
+                       AttrNumber      attnum = idxrec->indkey.values[keyno];
+
+                       aclresult = pg_attribute_aclcheck(indrelid, attnum, GetUserId(),
+                                                                                         ACL_SELECT);
+
+                       if (aclresult != ACLCHECK_OK)
+                       {
+                               /* No access, so clean up and return */
+                               ReleaseSysCache(ht_idx);
+                               return NULL;
+                       }
+               }
+       }
+       ReleaseSysCache(ht_idx);
 
        initStringInfo(&buf);
        appendStringInfo(&buf, "(%s)=(",
-                                        pg_get_indexdef_columns(RelationGetRelid(indexRelation),
-                                                                                        true));
+                                        pg_get_indexdef_columns(indexrelid, true));
 
        for (i = 0; i < natts; i++)
        {
index 1655494f59e1f0c3cab5276eabee60ab0df76d0f..80fc1eacfc467f71ea4becf5152c965c13ef020f 100644 (file)
@@ -376,16 +376,20 @@ _bt_check_unique(Relation rel, IndexTuple itup, Relation heapRel,
                                        {
                                                Datum           values[INDEX_MAX_KEYS];
                                                bool            isnull[INDEX_MAX_KEYS];
+                                               char       *key_desc;
 
                                                index_deform_tuple(itup, RelationGetDescr(rel),
                                                                                   values, isnull);
+
+                                               key_desc = BuildIndexValueDescription(rel, values,
+                                                                                                                         isnull);
+
                                                ereport(ERROR,
                                                                (errcode(ERRCODE_UNIQUE_VIOLATION),
                                                                 errmsg("duplicate key value violates unique constraint \"%s\"",
                                                                                RelationGetRelationName(rel)),
-                                                                errdetail("Key %s already exists.",
-                                                                                  BuildIndexValueDescription(rel,
-                                                                                                                 values, isnull))));
+                                                                key_desc ? errdetail("Key %s already exists.",
+                                                                                                         key_desc) : 0));
                                        }
                                }
                                else if (all_dead)
index 0971edb96dde85693568d4d253d81210dbc5a53a..e9be0f09fb2d29913d3c3b3c5c34fee3b895bf1d 100644 (file)
@@ -1687,6 +1687,7 @@ CopyFrom(CopyState cstate)
        bool            done = false;
        bool            isnull;
        ResultRelInfo *resultRelInfo;
+       RangeTblEntry *rte;
        EState     *estate = CreateExecutorState(); /* for ExecConstraints() */
        TupleTableSlot *slot;
        bool            file_has_oids;
@@ -1807,9 +1808,16 @@ CopyFrom(CopyState cstate)
 
        ExecOpenIndices(resultRelInfo);
 
+       /* Build an RTE to make into a RangeTbl for estate */
+       rte = makeNode(RangeTblEntry);
+       rte->rtekind = RTE_RELATION;
+       rte->relid = RelationGetRelid(cstate->rel);
+       rte->requiredPerms = ACL_INSERT;
+
        estate->es_result_relations = resultRelInfo;
        estate->es_num_result_relations = 1;
        estate->es_result_relation_info = resultRelInfo;
+       estate->es_range_table = list_make1(rte);
 
        /* Set up a tuple slot too */
        slot = ExecInitExtraTupleSlot(estate);
index f88a0e0778d46f06e6bc9402ec349acab6702824..1becace82c49faaaadc0f1de4e192e9643f8fa53 100644 (file)
 int                    SessionReplicationRole = SESSION_REPLICATION_ROLE_ORIGIN;
 
 
+/*
+ * Note that this macro also exists in executor/execMain.c.  There does not
+ * appear to be any good header to put it into, given the structures that
+ * it uses, so we let them be duplicated.  Be sure to update both if one needs
+ * to be changed, however.
+ */
 #define GetModifiedColumns(relinfo, estate) \
        (rt_fetch((relinfo)->ri_RangeTableIndex, (estate)->es_range_table)->modifiedCols)
 
index 19bfcd3e5ba7237ab95215660086eb4163ba78bf..f101226fdd2f534974064aedeb903defe7bf595e 100644 (file)
@@ -85,6 +85,15 @@ static void intorel_receive(TupleTableSlot *slot, DestReceiver *self);
 static void intorel_shutdown(DestReceiver *self);
 static void intorel_destroy(DestReceiver *self);
 
+/*
+ * Note that this macro also exists in commands/trigger.c.  There does not
+ * appear to be any good header to put it into, given the structures that
+ * it uses, so we let them be duplicated.  Be sure to update both if one needs
+ * to be changed, however.
+ */
+#define GetModifiedColumns(relinfo, estate) \
+       (rt_fetch((relinfo)->ri_RangeTableIndex, (estate)->es_range_table)->modifiedCols)
+
 /* end of local decls */
 
 
index 734ce5d7dfefd0ea0d5722b823591bf71173e478..bdd7b1cdefd3122f70b2d75c602733e1bdcb1f60 100644 (file)
@@ -1299,15 +1299,19 @@ retry:
                                        (errcode(ERRCODE_EXCLUSION_VIOLATION),
                                         errmsg("could not create exclusion constraint \"%s\"",
                                                        RelationGetRelationName(index)),
-                                        errdetail("Key %s conflicts with key %s.",
-                                                          error_new, error_existing)));
+                                        error_new && error_existing ?
+                                               errdetail("Key %s conflicts with key %s.",
+                                                                 error_new, error_existing) :
+                                               errdetail("Key conflicts exist.")));
                else
                        ereport(ERROR,
                                        (errcode(ERRCODE_EXCLUSION_VIOLATION),
                                         errmsg("conflicting key value violates exclusion constraint \"%s\"",
                                                        RelationGetRelationName(index)),
-                                        errdetail("Key %s conflicts with existing key %s.",
-                                                          error_new, error_existing)));
+                                        error_new && error_existing ?
+                                               errdetail("Key %s conflicts with existing key %s.",
+                                                                 error_new, error_existing) :
+                                               errdetail("Key conflicts with existing key.")));
        }
 
        index_endscan(index_scan);
index 8affb0c6903c001473bd12594fd72717ccc1aab6..2d420f41ea429230352c36a4699b44d710617d58 100644 (file)
@@ -3414,6 +3414,9 @@ ri_ReportViolation(RI_QueryKey *qkey, const char *constrname,
        bool            onfk;
        int                     idx,
                                key_idx;
+       Oid                     rel_oid;
+       AclResult       aclresult;
+       bool            has_perm = true;
 
        if (spi_err)
                ereport(ERROR,
@@ -3432,12 +3435,14 @@ ri_ReportViolation(RI_QueryKey *qkey, const char *constrname,
        if (onfk)
        {
                key_idx = RI_KEYPAIR_FK_IDX;
+               rel_oid = fk_rel->rd_id;
                if (tupdesc == NULL)
                        tupdesc = fk_rel->rd_att;
        }
        else
        {
                key_idx = RI_KEYPAIR_PK_IDX;
+               rel_oid = pk_rel->rd_id;
                if (tupdesc == NULL)
                        tupdesc = pk_rel->rd_att;
        }
@@ -3457,45 +3462,81 @@ ri_ReportViolation(RI_QueryKey *qkey, const char *constrname,
                                                   RelationGetRelationName(pk_rel))));
        }
 
-       /* Get printable versions of the keys involved */
-       initStringInfo(&key_names);
-       initStringInfo(&key_values);
-       for (idx = 0; idx < qkey->nkeypairs; idx++)
+       /*
+        * Check permissions- if the user does not have access to view the data in
+        * any of the key columns then we don't include the errdetail() below.
+        *
+        * Check table-level permissions first and, failing that, column-level
+        * privileges.
+        */
+       aclresult = pg_class_aclcheck(rel_oid, GetUserId(), ACL_SELECT);
+       if (aclresult != ACLCHECK_OK)
        {
-               int                     fnum = qkey->keypair[idx][key_idx];
-               char       *name,
-                                  *val;
-
-               name = SPI_fname(tupdesc, fnum);
-               val = SPI_getvalue(violator, tupdesc, fnum);
-               if (!val)
-                       val = "null";
+               /* Try for column-level permissions */
+               for (idx = 0; idx < qkey->nkeypairs; idx++)
+               {
+                       aclresult = pg_attribute_aclcheck(rel_oid, qkey->keypair[idx][key_idx],
+                                                                                         GetUserId(),
+                                                                                         ACL_SELECT);
+                       /* No access to the key */
+                       if (aclresult != ACLCHECK_OK)
+                       {
+                               has_perm = false;
+                               break;
+                       }
+               }
+       }
 
-               if (idx > 0)
+       if (has_perm)
+       {
+               /* Get printable versions of the keys involved */
+               initStringInfo(&key_names);
+               initStringInfo(&key_values);
+               for (idx = 0; idx < qkey->nkeypairs; idx++)
                {
-                       appendStringInfoString(&key_names, ", ");
-                       appendStringInfoString(&key_values, ", ");
+                       int                     fnum = qkey->keypair[idx][key_idx];
+                       char       *name,
+                                          *val;
+
+                       name = SPI_fname(tupdesc, fnum);
+                       val = SPI_getvalue(violator, tupdesc, fnum);
+                       if (!val)
+                               val = "null";
+
+                       if (idx > 0)
+                       {
+                               appendStringInfoString(&key_names, ", ");
+                               appendStringInfoString(&key_values, ", ");
+                       }
+                       appendStringInfoString(&key_names, name);
+                       appendStringInfoString(&key_values, val);
                }
-               appendStringInfoString(&key_names, name);
-               appendStringInfoString(&key_values, val);
        }
 
        if (onfk)
                ereport(ERROR,
                                (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
                                 errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
-                                               RelationGetRelationName(fk_rel), constrname),
-                                errdetail("Key (%s)=(%s) is not present in table \"%s\".",
-                                                  key_names.data, key_values.data,
-                                                  RelationGetRelationName(pk_rel))));
+                                               RelationGetRelationName(fk_rel),
+                                               constrname),
+                                has_perm ?
+                                        errdetail("Key (%s)=(%s) is not present in table \"%s\".",
+                                                          key_names.data, key_values.data,
+                                                          RelationGetRelationName(pk_rel)) :
+                                        errdetail("Key is not present in table \"%s\".",
+                                                          RelationGetRelationName(pk_rel))));
        else
                ereport(ERROR,
                                (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
                                 errmsg("update or delete on table \"%s\" violates foreign key constraint \"%s\" on table \"%s\"",
                                                RelationGetRelationName(pk_rel),
-                                               constrname, RelationGetRelationName(fk_rel)),
+                                               constrname,
+                                               RelationGetRelationName(fk_rel)),
+                                has_perm ?
                        errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
                                          key_names.data, key_values.data,
+                                         RelationGetRelationName(fk_rel)) :
+                                       errdetail("Key is still referenced from table \"%s\".",
                                          RelationGetRelationName(fk_rel))));
 }
 
index 9301f5a5a9a77a022e9145f449efe8fac6a9219e..4900796e4058cc42178b3bb4553c6b518c09d9c4 100644 (file)
@@ -2799,15 +2799,18 @@ comparetup_index_btree(const SortTuple *a, const SortTuple *b,
        {
                Datum           values[INDEX_MAX_KEYS];
                bool            isnull[INDEX_MAX_KEYS];
+               char       *key_desc;
 
                index_deform_tuple(tuple1, tupDes, values, isnull);
+
+               key_desc = BuildIndexValueDescription(state->indexRel, values, isnull);
+
                ereport(ERROR,
                                (errcode(ERRCODE_UNIQUE_VIOLATION),
                                 errmsg("could not create unique index \"%s\"",
                                                RelationGetRelationName(state->indexRel)),
-                                errdetail("Key %s is duplicated.",
-                                                  BuildIndexValueDescription(state->indexRel,
-                                                                                                         values, isnull))));
+                                key_desc ? errdetail("Key %s is duplicated.", key_desc) :
+                                                       errdetail("Duplicate keys exist.")));
        }
 
        /*
index b3e913de35498d6951bd124bc727d0ba7902675f..dfeb5bde12b856810e2df5cebd47b029add1cd22 100644 (file)
@@ -362,6 +362,34 @@ SELECT atest6 FROM atest6; -- ok
 (0 rows)
 
 COPY atest6 TO stdout; -- ok
+-- check error reporting with column privs
+SET SESSION AUTHORIZATION regressuser1;
+CREATE TABLE t1 (c1 int, c2 int, c3 int check (c3 < 5), primary key (c1, c2));
+NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "t1_pkey" for table "t1"
+GRANT SELECT (c1) ON t1 TO regressuser2;
+GRANT INSERT (c1, c2, c3) ON t1 TO regressuser2;
+GRANT UPDATE (c1, c2, c3) ON t1 TO regressuser2;
+-- seed data
+INSERT INTO t1 VALUES (1, 1, 1);
+INSERT INTO t1 VALUES (1, 2, 1);
+INSERT INTO t1 VALUES (2, 1, 2);
+INSERT INTO t1 VALUES (2, 2, 2);
+INSERT INTO t1 VALUES (3, 1, 3);
+SET SESSION AUTHORIZATION regressuser2;
+INSERT INTO t1 (c1, c2) VALUES (1, 1); -- fail, but row not shown
+ERROR:  duplicate key value violates unique constraint "t1_pkey"
+UPDATE t1 SET c2 = 1; -- fail, but row not shown
+ERROR:  duplicate key value violates unique constraint "t1_pkey"
+INSERT INTO t1 (c1, c2) VALUES (null, null); -- fail, but see columns being inserted
+ERROR:  null value in column "c1" violates not-null constraint
+INSERT INTO t1 (c3) VALUES (null); -- fail, but see columns being inserted or have SELECT
+ERROR:  null value in column "c1" violates not-null constraint
+INSERT INTO t1 (c1) VALUES (5); -- fail, but see columns being inserted or have SELECT
+ERROR:  null value in column "c2" violates not-null constraint
+UPDATE t1 SET c3 = 10; -- fail, but see columns with SELECT rights, or being modified
+ERROR:  new row for relation "t1" violates check constraint "t1_c3_check"
+SET SESSION AUTHORIZATION regressuser1;
+DROP TABLE t1;
 -- test column-level privileges when involved with DELETE
 SET SESSION AUTHORIZATION regressuser1;
 ALTER TABLE atest6 ADD COLUMN three integer;
index cc9d85779027a95697a20e00b084bb177397981f..f3cc04bd1d378c45fba9cfecfb408ff18d668b80 100644 (file)
@@ -238,6 +238,31 @@ UPDATE atest5 SET one = 1; -- fail
 SELECT atest6 FROM atest6; -- ok
 COPY atest6 TO stdout; -- ok
 
+-- check error reporting with column privs
+SET SESSION AUTHORIZATION regressuser1;
+CREATE TABLE t1 (c1 int, c2 int, c3 int check (c3 < 5), primary key (c1, c2));
+GRANT SELECT (c1) ON t1 TO regressuser2;
+GRANT INSERT (c1, c2, c3) ON t1 TO regressuser2;
+GRANT UPDATE (c1, c2, c3) ON t1 TO regressuser2;
+
+-- seed data
+INSERT INTO t1 VALUES (1, 1, 1);
+INSERT INTO t1 VALUES (1, 2, 1);
+INSERT INTO t1 VALUES (2, 1, 2);
+INSERT INTO t1 VALUES (2, 2, 2);
+INSERT INTO t1 VALUES (3, 1, 3);
+
+SET SESSION AUTHORIZATION regressuser2;
+INSERT INTO t1 (c1, c2) VALUES (1, 1); -- fail, but row not shown
+UPDATE t1 SET c2 = 1; -- fail, but row not shown
+INSERT INTO t1 (c1, c2) VALUES (null, null); -- fail, but see columns being inserted
+INSERT INTO t1 (c3) VALUES (null); -- fail, but see columns being inserted or have SELECT
+INSERT INTO t1 (c1) VALUES (5); -- fail, but see columns being inserted or have SELECT
+UPDATE t1 SET c3 = 10; -- fail, but see columns with SELECT rights, or being modified
+
+SET SESSION AUTHORIZATION regressuser1;
+DROP TABLE t1;
+
 -- test column-level privileges when involved with DELETE
 SET SESSION AUTHORIZATION regressuser1;
 ALTER TABLE atest6 ADD COLUMN three integer;