7.4.27.
an allegedly immutable index function. It was previously recognized that we had to prevent such a function from executing SET/RESET ROLE/SESSION AUTHORIZATION, or it could trivially obtain the privileges of the session user. However, since there is in general no privilege checking for changes of session-local state, it is also possible for such a function to change settings in a way that might subvert later operations in the same session. Examples include changing search_path to cause an unexpected function to be called, or replacing an existing prepared statement with another one that will execute a function of the attacker's choosing. The present patch secures VACUUM, ANALYZE, and CREATE INDEX/REINDEX against these threats, which are the same places previously deemed to need protection against the SET ROLE issue. GUC changes are still allowed, since there are many useful cases for that, but we prevent security problems by forcing a rollback of any GUC change after completing the operation. Other cases are handled by throwing an error if any change is attempted; these include temp table creation, closing a cursor, and creating or deleting a prepared statement. (In 7.4, the infrastructure to roll back GUC changes doesn't exist, so we settle for rejecting changes of "search_path" in these contexts.) Original report and patch by Gurjeet Singh, additional analysis by Tom Lane. Security: CVE-2009-4136
attacks where an attacker would put <attack>\0<propername> in the field and trick the validation code that the certificate was for <attack>. This is a very low risk attack since it reuqires the attacker to trick the CA into issuing a certificate with an incorrect field, and the common PostgreSQL deployments are with private CAs, and not external ones. Also, default mode in 8.4 does not do any name validation, and is thus also not vulnerable - but the higher security modes are. Backpatch all the way. Even though versions 8.3.x and before didn't have certificate name validation support, they still exposed this field for the user to perform the validation in the application code, and there is no way to detect this problem through that API. Security: CVE-2009-4034
Antarctica, Argentina, Bangladesh, Fiji, Novokuznetsk, Pakistan, Palestine, Samoa, Syria. Also historical corrections for Hong Kong.
in a subtransaction stays open even if the subtransaction is aborted, so any temporary files related to it must stay alive as well. With the patch, we use ResourceOwners to track open temporary files and don't automatically close them at subtransaction end (though in the normal case temporary files are registered with the subtransaction resource owner and will therefore be closed). At end of top transaction, we still check that there's no temporary files marked as close-at-end-of-transaction open, but that's now just a debugging cross-check as the resource owner cleanup should've closed them already.
This avoids a useless connection retry and complaint in the postmaster log when receiving a connection from 8.5 or later libpq. Backpatch in all supported branches, but of course *not* HEAD.
we have to tell Perl it can release its compiled copy of the function text. Noted by Alexey Klyukin. Back-patch to 8.2 --- the problem exists further back, but this patch won't work without modification, and it's probably not worth the trouble.
be part of multixacts, so allocate a slot for each prepared transaction in the "oldest member" array in multixact.c. On PREPARE TRANSACTION, transfer the oldest member value from the current backends slot to the prepared xact slot. Also save and recover the value from the 2pc state file. The symptom of the bug was that after a transaction prepared, a shared lock still held by the prepared transaction was sometimes ignored by other transactions. Fix back to 8.1, where both 2PC and multixact were introduced.