Commit 28972b6fc ("Add support for importing statistics from remote
servers.") stored the names of local/remote columns for a foreign table
into the buffers of NAMEDATALEN bytes in this structure, without
accounting for the possibility that the remote column name in particular
could be longer than NAMEDATALEN - 1. If it was longer than that, this
would leave it unterminated/truncated in the buffer, invoking undefined
behavior when match_attrmap() processes it, which assumes that it's
fully-contained/terminated in the buffer.
To fix, replace the buffers with char pointers, pstrdup the local/remote
column names, and store the results into the pointers. This commit also
adds a function to clean up the nested data structure.
Per Coverity and Tom Lane.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Author: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Etsuro Fujita <etsuro.fujita@gmail.com>
Discussion: https://postgr.es/m/342868.1776017700%40sss.pgh.pa.us
The PostgreSQL contrib tree
---------------------------
This subtree contains porting tools, analysis utilities, and plug-in
features that are not part of the core PostgreSQL system, mainly
because they address a limited audience or are too experimental to be
part of the main source tree. This does not preclude their
usefulness.
User documentation for each module appears in the main SGML
documentation.
When building from the source distribution, these modules are not
built automatically, unless you build the "world" target. You can
also build and install them all by running "make all" and "make
install" in this directory; or to build and install just one selected
module, do the same in that module's subdirectory.
Some directories supply new user-defined functions, operators, or
types. To make use of one of these modules, after you have installed
the code you need to register the new SQL objects in the database
system by executing a CREATE EXTENSION command. In a fresh database,
you can simply do
CREATE EXTENSION module_name;
See the PostgreSQL documentation for more information about this
procedure.