Обсуждение: pgsql: Catch stack overflow when recursing in transformFromClauseItem()

Catch stack overflow when recursing in transformFromClauseItem().

Most parts of the parser can expect that the stack overflow check
in transformExprRecurse() will trigger before things get desperate.
However, transformFromClauseItem() can recurse directly to self
without having analyzed any expressions, so it's possible to drive
it to a stack-overrun crash.  Add a check to prevent that.

Per bug #17583 from Egor Chindyaskin.  Back-patch to all supported
branches.

Richard Guo

Discussion: https://postgr.es/m/17583-33be55b9f981f75c@postgresql.org

Branch
------
REL_14_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/496ab1d6c8d853899595e986f04cd70c4b13dac4

Modified Files
--------------
src/backend/parser/parse_clause.c | 3 +++
1 file changed, 3 insertions(+)