Bug #53371: COM_FIELD_LIST can be abused to bypass table level grants.

This is the 5.1 merge and extension of the fix.
The server was happily accepting paths in table name in all places a table
name is accepted (e.g. a SELECT). This allowed all users that have some 
privilege over some database to read all tables in all databases in all
mysql server instances that the server file system has access to.
Fixed by :
1. making sure no path elements are allowed in quoted table name when
constructing the path (note that the path symbols are still valid in table names
when they're properly escaped by the server).
2. checking the #mysql50# prefixed names the same way they're checked for
path elements in mysql-5.0.

1 files changed, 16 insertions, 0 deletions

diff --git a/mysql-test/r/grant.result b/mysql-test/r/grant.result
index 92beccd2a9e..6831ef6183d 100644
--- a/mysql-test/r/grant.result
+++ b/mysql-test/r/grant.result
@@ -1413,3 +1413,19 @@ DROP USER 'user1';
 DROP USER 'user1'@'localhost';
 DROP USER 'user2';
 DROP DATABASE db1;
+CREATE DATABASE db1;
+CREATE DATABASE db2;
+GRANT SELECT ON db1.* to 'testbug'@localhost;
+USE db2;
+CREATE TABLE t1 (a INT);
+USE test;
+SELECT * FROM `../db2/tb2`;
+ERROR 42S02: Table 'db1.../db2/tb2' doesn't exist
+SELECT * FROM `../db2`.tb2;
+ERROR 42000: SELECT command denied to user 'testbug'@'localhost' for table 'tb2'
+SELECT * FROM `#mysql50#/../db2/tb2`;
+ERROR 42S02: Table 'db1.#mysql50#/../db2/tb2' doesn't exist
+DROP USER 'testbug'@localhost;
+DROP TABLE db2.t1;
+DROP DATABASE db1;
+DROP DATABASE db2;