amcheck: Fix parent key check in gin_index_check()
The checks introduced by commit 14ffaece0fb5 did not get the parent key
checks quite right, missing some data corruption cases. In particular:
* The "rightlink" check was not working as intended, because rightlink
is a BlockNumber, and InvalidBlockNumber is 0xFFFFFFFF, so
!GinPageGetOpaque(page)->rightlink
almost always evaluates to false (except for rightlink=0). So in most
cases parenttup was left NULL, preventing any checks against parent.
* Use GinGetDownlink() to retrieve child blkno to avoid triggering
Assert, same as the core GIN code.
Issues reported by Arseniy Mukhin, along with a proposed patch. Review
by Andrey M. Borodin, cleanup and improvements by me.
Author: Arseniy Mukhin <arseniy.mukhin....@gmail.com>
Reviewed-by: Andrey M. Borodin <x4...@yandex-team.ru>
Discussion:
https://postgr.es/m/CAE7r3MJ611B9TE=yqbbncewp7-k64vws+sjk7xf6fjux77u...@mail.gmail.com
Branch
------
master
Details
-------
https://git.postgresql.org/pg/commitdiff/cdd1a431f21dbd2b7b675a9db1c24b97d713f38b
Modified Files
--------------
contrib/amcheck/t/006_verify_gin.pl | 78 +++++++++++++++++++++++++++++++++++++
contrib/amcheck/verify_gin.c | 8 ++--
2 files changed, 82 insertions(+), 4 deletions(-)
