Thread: [COMMITTERS] pgsql: Fix crash when columns have been added to the end of a view.
[COMMITTERS] pgsql: Fix crash when columns have been added to the end of a view.
From
Tom Lane
Date:
Fix crash when columns have been added to the end of a view. expandRTE() supposed that an RTE_SUBQUERY subquery must have exactly as many non-junk tlist items as the RTE has column aliases for it. This was true at the time the code was written, and is still true so far as parse analysis is concerned --- but when the function is used during planning, the subquery might have appeared through insertion of a view that now has more columns than it did when the outer query was parsed. This results in a core dump if, for instance, we have to expand a whole-row Var that references the subquery. To avoid crashing, we can either stop expanding the RTE when we run out of aliases, or invent new aliases for the added columns. While the latter might be more useful, the former is consistent with what expandRTE() does for composite-returning functions in the RTE_FUNCTION case, so it seems like we'd better do it that way. Per bug #14876 from Samuel Horwitz. This has been busted since commit ff1ea2173 allowed views to acquire more columns, so back-patch to all supported branches. Discussion: https://postgr.es/m/20171026184035.1471.82810@wrigleys.postgresql.org Branch ------ REL9_3_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/9d15b8b36a9185f9990309770f480900310c75d4 Modified Files -------------- src/backend/parser/parse_relation.c | 12 ++++- src/test/regress/expected/alter_table.out | 85 +++++++++++++++++++++++++++++++ src/test/regress/sql/alter_table.sql | 20 ++++++++ 3 files changed, 116 insertions(+), 1 deletion(-) -- Sent via pgsql-committers mailing list (pgsql-committers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-committers