From 928bca1a30d7e05cc3857a99e27aa8ed08ed2fac Mon Sep 17 00:00:00 2001 From: Noah Misch Date: Mon, 26 Feb 2018 07:39:44 -0800 Subject: Empty search_path in Autovacuum and non-psql/pgbench clients. This makes the client programs behave as documented regardless of the connect-time search_path and regardless of user-created objects. Today, a malicious user with CREATE permission on a search_path schema can take control of certain of these clients' queries and invoke arbitrary SQL functions under the client identity, often a superuser. This is exploitable in the default configuration, where all users have CREATE privilege on schema "public". This changes behavior of user-defined code stored in the database, like pg_index.indexprs and pg_extension_config_dump(). If they reach code bearing unqualified names, "does not exist" or "no schema has been selected to create in" errors might appear. Users may fix such errors by schema-qualifying affected names. After upgrading, consider watching server logs for these errors. The --table arguments of src/bin/scripts clients have been lax; for example, "vacuumdb -Zt pg_am\;CHECKPOINT" performed a checkpoint. That now fails, but for now, "vacuumdb -Zt 'pg_am(amname);CHECKPOINT'" still performs a checkpoint. Back-patch to 9.3 (all supported versions). Reviewed by Tom Lane, though this fix strategy was not his first choice. Reported by Arseniy Sharoglazov. Security: CVE-2018-1058 --- src/bin/pg_dump/dumputils.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) (limited to 'src/bin/pg_dump/dumputils.c') diff --git a/src/bin/pg_dump/dumputils.c b/src/bin/pg_dump/dumputils.c index fdf9d47b644..8eb9e0c9926 100644 --- a/src/bin/pg_dump/dumputils.c +++ b/src/bin/pg_dump/dumputils.c @@ -1376,8 +1376,9 @@ processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern, } /* - * Now decide what we need to emit. Note there will be a leading "^(" in - * the patterns in any case. + * Now decide what we need to emit. We may run under a hostile + * search_path, so qualify EVERY name. Note there will be a leading "^(" + * in the patterns in any case. */ if (namebuf.len > 2) { @@ -1390,15 +1391,18 @@ processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern, WHEREAND(); if (altnamevar) { - appendPQExpBuffer(buf, "(%s ~ ", namevar); + appendPQExpBuffer(buf, + "(%s OPERATOR(pg_catalog.~) ", namevar); appendStringLiteralConn(buf, namebuf.data, conn); - appendPQExpBuffer(buf, "\n OR %s ~ ", altnamevar); + appendPQExpBuffer(buf, + "\n OR %s OPERATOR(pg_catalog.~) ", + altnamevar); appendStringLiteralConn(buf, namebuf.data, conn); appendPQExpBufferStr(buf, ")\n"); } else { - appendPQExpBuffer(buf, "%s ~ ", namevar); + appendPQExpBuffer(buf, "%s OPERATOR(pg_catalog.~) ", namevar); appendStringLiteralConn(buf, namebuf.data, conn); appendPQExpBufferChar(buf, '\n'); } @@ -1414,7 +1418,7 @@ processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern, if (strcmp(schemabuf.data, "^(.*)$") != 0 && schemavar) { WHEREAND(); - appendPQExpBuffer(buf, "%s ~ ", schemavar); + appendPQExpBuffer(buf, "%s OPERATOR(pg_catalog.~) ", schemavar); appendStringLiteralConn(buf, schemabuf.data, conn); appendPQExpBufferChar(buf, '\n'); } -- cgit v1.2.3