## E.231. Release 8.1.20

Release date: 2010-03-15

This release contains a variety of fixes from 8.1.19. For information about new features in the 8.1 major release, see Section E.251.

### E.231.1. Migration to Version 8.1.20

A dump/restore is not required for those running 8.1.X. However, if you are upgrading from a version earlier than 8.1.18, see Section E.233.

### E.231.2. Changes

- Add new configuration parameter `ssl_renegotiation_limit` to control how often we do session key renegotiation for an SSL connection (Magnus)

  This can be set to zero to disable renegotiation completely, which may be required if a broken SSL library is used. In particular, some vendors are shipping stopgap patches for CVE-2009-3555 that cause renegotiation attempts to fail.

- Fix possible crashes when trying to recover from a failure in subtransaction start (Tom)

- Fix server memory leak associated with use of savepoints and a client encoding different from server's encoding (Tom)

- Make `substring()` for `bit` types treat any negative length as meaning “all the rest of the string” (Tom)

  The previous coding treated only -1 that way, and would produce an invalid result value for other negative values, possibly leading to a crash (CVE-2010-0442).

- Fix integer-to-bit-string conversions to handle the first fractional byte correctly when the output bit width is wider than the given integer by something other than a multiple of 8 bits (Tom)

- Fix some cases of pathologically slow regular expression matching (Tom)

- Fix the `STOP WAL LOCATION` entry in backup history files to report the next WAL segment's name when the end location is exactly at a segment boundary (Itagaki Takahiro)

- Fix some more cases of temporary-file leakage (Heikki)

  This corrects a problem introduced in the previous minor release. One case that failed is when a plpgsql function returning set is called within another function's exception handler.

- When reading `pg_hba.conf` and related files, do not treat `@something` as a file inclusion request if the `@` appears inside quote marks; also, never treat `@` by itself as a file inclusion request (Tom)

  This prevents erratic behavior if a role or database name starts with `@`. If you need to include a file whose path name contains spaces, you can still do so, but you must write `@"/path to/file"` rather than putting the quotes around the whole construct.

- Prevent infinite loop on some platforms if a directory is named as an inclusion target in `pg_hba.conf` and related files (Tom)

- Fix psql's `numericlocale` option to not format strings it shouldn't in latex and troff output formats (Heikki)

- Fix plpgsql failure in one case where a composite column is set to NULL (Tom)

- Add `volatile` markings in PL/Python to avoid possible compiler-specific misbehavior (Zdenek Kotala)

- Ensure PL/Tcl initializes the Tcl interpreter fully (Tom)

  The only known symptom of this oversight is that the Tcl `clock` command misbehaves if using Tcl 8.5 or later.

- Prevent crash in `contrib/dblink` when too many key columns are specified to a `dblink_build_sql_*` function (Rushabh Lathia, Joe Conway)

- Fix assorted crashes in `contrib/xml2` caused by sloppy memory management (Tom)

- Update time zone data files to tzdata release 2010e for DST law changes in Bangladesh, Chile, Fiji, Mexico, Paraguay, Samoa.