From: | Heikki Linnakangas <heikki(dot)linnakangas(at)iki(dot)fi> |
---|---|
To: | pgsql-committers(at)postgresql(dot)org |
Subject: | pgsql: Initialize padding bytes in btree_gist varbit support. |
Date: | 2014-05-13 12:32:06 |
Message-ID: | E1WkBsM-0004kP-Jg@gemulon.postgresql.org |
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Lists: | pgsql-committers |
Initialize padding bytes in btree_gist varbit support.
The code expands a varbit gist leaf key to a node key by copying the bit
data twice in a varlen datum, as both the lower and upper key. The lower key
was expanded to INTALIGN size, but the padding bytes were not initialized.
That's a problem because when the lower/upper keys are compared, the padding
bytes are used compared too, when the values are otherwise equal. That could
lead to incorrect query results.
REINDEX is advised for any btree_gist indexes on bit or bit varying data
type, to fix any garbage padding bytes on disk.
Per Valgrind, reported by Andres Freund. Backpatch to all supported
versions.
Branch
------
REL9_2_STABLE
Details
-------
http://git.postgresql.org/pg/commitdiff/0d8d0d027723d4470a9e2571c499752aa6d8df7a
Modified Files
--------------
contrib/btree_gist/btree_bit.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
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Next Message | Heikki Linnakangas | 2014-05-13 16:19:58 | pgsql: Fix harmless access to uninitialized memory. |
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