postgres.git / summary / log / commit / refs
commit c2f78e5e02e72e7f74f549fa07a435b1264ba308
Author: Robert Haas <rhaas@postgresql.org>
Date: Thu Dec 22 18:54:40 2016 +0000
Fix broken error check in _hash_doinsert.
You can't just cast a HashMetaPage to a Page, because the meta page
data is stored after the page header, not at offset 0. Fortunately,
this didn't break anything because it happens to find hashm_bsize
at the offset at which it expects to find pd_pagesize_version, and
the values are close enough to the same that this works out.
Still, it's a bug, so back-patch to all supported versions.
Mithun Cy, revised a bit by me.
src/backend/access/hash/hashinsert.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/src/backend/access/hash/hashinsert.c b/src/backend/access/hash/hashinsert.c
index 05e9808b8ad..fea18d86b2f 100644
--- a/src/backend/access/hash/hashinsert.c
+++ b/src/backend/access/hash/hashinsert.c
@@ -34,6 +34,7 @@ _hash_doinsert(Relation rel, IndexTuple itup)
BlockNumber blkno;
BlockNumber oldblkno = InvalidBlockNumber;
bool retry = false;
+ Page metapage;
Page page;
HashPageOpaque pageopaque;
Size itemsz;
@@ -53,7 +54,8 @@ _hash_doinsert(Relation rel, IndexTuple itup)
/* Read the metapage */
metabuf = _hash_getbuf(rel, HASH_METAPAGE, HASH_READ, LH_META_PAGE);
- metap = HashPageGetMeta(BufferGetPage(metabuf));
+ metapage = BufferGetPage(metabuf);
+ metap = HashPageGetMeta(metapage);
/*
* Check whether the item can fit on a hash page at all. (Eventually, we
@@ -62,11 +64,11 @@ _hash_doinsert(Relation rel, IndexTuple itup)
*
* XXX this is useless code if we are only storing hash keys.
*/
- if (itemsz > HashMaxItemSize((Page) metap))
+ if (itemsz > HashMaxItemSize(metapage))
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("index row size %zu exceeds hash maximum %zu",
- itemsz, HashMaxItemSize((Page) metap)),
+ itemsz, HashMaxItemSize(metapage)),
errhint("Values larger than a buffer page cannot be indexed.")));
/*
[parent: 76943f54a743]