During the split, set checksum on an empty hash index page.

On a split, we allocate a new splitpoint's worth of bucket pages wherein
we initialize the last page with zeros which is fine, but we forgot to set
the checksum for that last page.

We decided to back-patch this fix till 10 because we don't have an easy
way to test it in prior versions.  Another reason is that the hash-index
code is changed heavily in 10, so it is not advisable to push the fix
without testing it in prior versions.

Author: Amit Kapila
Reviewed-by: Yugo Nagata
Backpatch-through: 10
Discussion: https://postgr.es/m/5d03686d-727c-dbf8-0064-bf8b97ffe850@2ndquadrant.com

diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c
index 69a9c4f1feed3e2bf6f75fd04b59f63a3ef53a52..6825c14309b6235d6270da93135c29c76cee7480 100644 (file)
--- a/src/backend/access/hash/hashpage.c
+++ b/src/backend/access/hash/hashpage.c
@@ -1038,6 +1038,7 @@ _hash_alloc_buckets(Relation rel, BlockNumber firstblock, uint32 nblocks)
                                        true);
 
        RelationOpenSmgr(rel);
+       PageSetChecksumInplace(page, lastblock);
        smgrextend(rel->rd_smgr, MAIN_FORKNUM, lastblock, zerobuf.data, false);
 
        return true;