Check to ensure the number of primary key fields supplied does not

exceed the total number of non-dropped source table fields for
dblink_build_sql_*(). Addresses bug report from Rushabh Lathia.

Backpatch all the way to the 7.3 branch.

diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index 2ed84da217de452ceb1f3a8f7f8e19adb5d73299..b901c3941fec48ee3a463ef771fda1e9b7221d8f 100644 (file)
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -76,6 +76,7 @@ static void remove_res_ptr(dblink_results * results);
 static char *generate_relation_name(Oid relid);
 static char *connstr_strip_password(const char *connstr);
 static void dblink_security_check(PGconn *conn, const char *connstr);
+static int get_nondropped_natts(Oid relid);
 
 /* Global */
 List      *res_id = NIL;
@@ -1100,6 +1101,7 @@ dblink_build_sql_insert(PG_FUNCTION_ARGS)
        int16           typlen;
        bool            typbyval;
        char            typalign;
+       int                     nondropped_natts;
 
        relname_text = PG_GETARG_TEXT_P(0);
 
@@ -1123,6 +1125,14 @@ dblink_build_sql_insert(PG_FUNCTION_ARGS)
        if (pknumatts == 0)
                elog(ERROR, "dblink_build_sql_insert: number of key attributes must be > 0.");
 
+       /*
+        * ensure we don't ask for more pk attributes than we have
+        * non-dropped columns
+        */
+       nondropped_natts = get_nondropped_natts(relid);
+       if (pknumatts > nondropped_natts)
+               elog(ERROR, "number of primary key fields exceeds number of specified relation attributes");
+
        src_pkattvals_arry = PG_GETARG_ARRAYTYPE_P(3);
        tgt_pkattvals_arry = PG_GETARG_ARRAYTYPE_P(4);
 
@@ -1239,6 +1249,7 @@ dblink_build_sql_delete(PG_FUNCTION_ARGS)
        int16           typlen;
        bool            typbyval;
        char            typalign;
+       int                     nondropped_natts;
 
        relname_text = PG_GETARG_TEXT_P(0);
 
@@ -1262,6 +1273,14 @@ dblink_build_sql_delete(PG_FUNCTION_ARGS)
        if (pknumatts == 0)
                elog(ERROR, "dblink_build_sql_insert: number of key attributes must be > 0.");
 
+       /*
+        * ensure we don't ask for more pk attributes than we have
+        * non-dropped columns
+        */
+       nondropped_natts = get_nondropped_natts(relid);
+       if (pknumatts > nondropped_natts)
+               elog(ERROR, "number of primary key fields exceeds number of specified relation attributes");
+
        tgt_pkattvals_arry = PG_GETARG_ARRAYTYPE_P(3);
 
        /*
@@ -1356,6 +1375,7 @@ dblink_build_sql_update(PG_FUNCTION_ARGS)
        int16           typlen;
        bool            typbyval;
        char            typalign;
+       int                     nondropped_natts;
 
        relname_text = PG_GETARG_TEXT_P(0);
 
@@ -1379,6 +1399,14 @@ dblink_build_sql_update(PG_FUNCTION_ARGS)
        if (pknumatts == 0)
                elog(ERROR, "dblink_build_sql_insert: number of key attributes must be > 0.");
 
+       /*
+        * ensure we don't ask for more pk attributes than we have
+        * non-dropped columns
+        */
+       nondropped_natts = get_nondropped_natts(relid);
+       if (pknumatts > nondropped_natts)
+               elog(ERROR, "number of primary key fields exceeds number of specified relation attributes");
+
        src_pkattvals_arry = PG_GETARG_ARRAYTYPE_P(3);
        tgt_pkattvals_arry = PG_GETARG_ARRAYTYPE_P(4);
 
@@ -2191,3 +2219,27 @@ dblink_security_check(PGconn *conn, const char *connstr)
                        PQfinish(conn);
        }
 }
+
+static int
+get_nondropped_natts(Oid relid)
+{
+       int                     nondropped_natts = 0;
+       TupleDesc       tupdesc;
+       Relation        rel;
+       int                     natts;
+       int                     i;
+
+       rel = relation_open(relid, AccessShareLock);
+       tupdesc = rel->rd_att;
+       natts = tupdesc->natts;
+
+       for (i = 0; i < natts; i++)
+       {
+               if (tupdesc->attrs[i]->attisdropped)
+                       continue;
+               nondropped_natts++;
+       }
+
+       relation_close(rel, AccessShareLock);
+       return nondropped_natts;
+}

diff --git a/contrib/dblink/expected/dblink.out b/contrib/dblink/expected/dblink.out
index ed3a87cfa0eeb4cee3d19c362ed79a592b90c8cf..326fc9f40d4d7dd2e134e3bf442036ffa9aed8f4 100644 (file)
--- a/contrib/dblink/expected/dblink.out
+++ b/contrib/dblink/expected/dblink.out
@@ -44,6 +44,9 @@ SELECT dblink_build_sql_insert('foo','1 2',2,'{"0", "a"}','{"99", "xyz"}');
  INSERT INTO foo(f1,f2,f3) VALUES('99','xyz','{a0,b0,c0}')
 (1 row)
 
+-- too many pk fields, should fail
+SELECT dblink_build_sql_insert('foo','1 2 3 4',4,'{"0", "a", "{a0,b0,c0}"}','{"99", "xyz", "{za0,zb0,zc0}"}');
+ERROR:  number of primary key fields exceeds number of specified relation attributes
 -- build an update statement based on a local tuple,
 -- replacing the primary key values with new ones
 SELECT dblink_build_sql_update('foo','1 2',2,'{"0", "a"}','{"99", "xyz"}');
@@ -52,6 +55,9 @@ SELECT dblink_build_sql_update('foo','1 2',2,'{"0", "a"}','{"99", "xyz"}');
  UPDATE foo SET f1 = '99', f2 = 'xyz', f3 = '{a0,b0,c0}' WHERE f1 = '99' AND f2 = 'xyz'
 (1 row)
 
+-- too many pk fields, should fail
+SELECT dblink_build_sql_update('foo','1 2 3 4',4,'{"0", "a", "{a0,b0,c0}"}','{"99", "xyz", "{za0,zb0,zc0}"}');
+ERROR:  number of primary key fields exceeds number of specified relation attributes
 -- build a delete statement based on a local tuple,
 SELECT dblink_build_sql_delete('foo','1 2',2,'{"0", "a"}');
            dblink_build_sql_delete           
@@ -59,6 +65,9 @@ SELECT dblink_build_sql_delete('foo','1 2',2,'{"0", "a"}');
  DELETE FROM foo WHERE f1 = '0' AND f2 = 'a'
 (1 row)
 
+-- too many pk fields, should fail
+SELECT dblink_build_sql_delete('foo','1 2 3 4',4,'{"0", "a", "{a0,b0,c0}"}');
+ERROR:  number of primary key fields exceeds number of specified relation attributes
 -- retest using a quoted and schema qualified table
 CREATE SCHEMA "MySchema";
 CREATE TABLE "MySchema"."Foo"(f1 int, f2 text, f3 text[], primary key (f1,f2));

diff --git a/contrib/dblink/sql/dblink.sql b/contrib/dblink/sql/dblink.sql
index 4d534e50c1cf79219fdf3a6fc9e8de29a9365b61..454e1dab11a6c446d8ed3fcb1ed59379b7960e16 100644 (file)
--- a/contrib/dblink/sql/dblink.sql
+++ b/contrib/dblink/sql/dblink.sql
@@ -36,13 +36,19 @@ FROM dblink_get_pkey('foo');
 -- build an insert statement based on a local tuple,
 -- replacing the primary key values with new ones
 SELECT dblink_build_sql_insert('foo','1 2',2,'{"0", "a"}','{"99", "xyz"}');
+-- too many pk fields, should fail
+SELECT dblink_build_sql_insert('foo','1 2 3 4',4,'{"0", "a", "{a0,b0,c0}"}','{"99", "xyz", "{za0,zb0,zc0}"}');
 
 -- build an update statement based on a local tuple,
 -- replacing the primary key values with new ones
 SELECT dblink_build_sql_update('foo','1 2',2,'{"0", "a"}','{"99", "xyz"}');
+-- too many pk fields, should fail
+SELECT dblink_build_sql_update('foo','1 2 3 4',4,'{"0", "a", "{a0,b0,c0}"}','{"99", "xyz", "{za0,zb0,zc0}"}');
 
 -- build a delete statement based on a local tuple,
 SELECT dblink_build_sql_delete('foo','1 2',2,'{"0", "a"}');
+-- too many pk fields, should fail
+SELECT dblink_build_sql_delete('foo','1 2 3 4',4,'{"0", "a", "{a0,b0,c0}"}');
 
 -- retest using a quoted and schema qualified table
 CREATE SCHEMA "MySchema";