Fix bogus Name assignment in CreateStatistics

Apparently, it doesn't work to use a plain cstring as a Name datum: you
may end up having random bytes because of failing to zero the bytes
after the terminating \0, as indicated by valgrind.  I introduced this
bug in 5564c11815, so backpatch this fix to REL_10_STABLE, like that
commit.

While at it, fix a slightly misleading comment, pointed out by David
Rowley.
This commit is contained in:
Alvaro Herrera 2018-03-06 13:17:13 -03:00
parent 4c831aeaa7
commit 1ffb63a2a1
2 changed files with 7 additions and 3 deletions

View File

@ -57,6 +57,7 @@ CreateStatistics(CreateStatsStmt *stmt)
int16 attnums[STATS_MAX_DIMENSIONS];
int numcols = 0;
char *namestr;
NameData stxname;
Oid statoid;
Oid namespaceId;
Oid stxowner = GetUserId();
@ -135,7 +136,8 @@ CreateStatistics(CreateStatsStmt *stmt)
* object in the same namespace as the relation, and cons up a name for it.
*/
if (stmt->defnames)
namespaceId = QualifiedNameGetCreationNamespace(stmt->defnames, &namestr);
namespaceId = QualifiedNameGetCreationNamespace(stmt->defnames,
&namestr);
else
{
namespaceId = RelationGetNamespace(rel);
@ -144,6 +146,7 @@ CreateStatistics(CreateStatsStmt *stmt)
"stat",
namespaceId);
}
namestrcpy(&stxname, namestr);
/*
* Deal with the possibility that the statistics object already exists.
@ -307,7 +310,7 @@ CreateStatistics(CreateStatsStmt *stmt)
memset(values, 0, sizeof(values));
memset(nulls, false, sizeof(nulls));
values[Anum_pg_statistic_ext_stxrelid - 1] = ObjectIdGetDatum(relid);
values[Anum_pg_statistic_ext_stxname - 1] = CStringGetDatum(namestr);
values[Anum_pg_statistic_ext_stxname - 1] = NameGetDatum(&stxname);
values[Anum_pg_statistic_ext_stxnamespace - 1] = ObjectIdGetDatum(namespaceId);
values[Anum_pg_statistic_ext_stxowner - 1] = ObjectIdGetDatum(stxowner);
values[Anum_pg_statistic_ext_stxkeys - 1] = PointerGetDatum(stxkeys);

View File

@ -2250,7 +2250,8 @@ transformIndexConstraint(Constraint *constraint, CreateStmtContext *cxt)
* transformExtendedStatistics
* Handle extended statistic objects
*
* Right now, there's nothing to do here, so we just copy the list.
* Right now, there's nothing to do here, so we just append the list to
* the existing "after" list.
*/
static void
transformExtendedStatistics(CreateStmtContext *cxt)