Bug #83913 symbolic-link / have_symlink is not dynamic and the names are inconsistent

• Submitted: 21 Nov 2016 22:11
• Modified: 24 Nov 2016 8:01
• Reporter: Simon Mudd (OCA)
• Status: Verified
• Category: MySQL Server: Options
• Severity: S4 (Feature request)
• Version: 5.6.33,5.7.15
• OS: Any
• CPU Architecture: Any
• Tags: have_symlink, symbolic-links

[21 Nov 2016 22:11] Simon Mudd

Description:
https://dev.mysql.com/doc/refman/5.7/en/security-against-attack.html says to disable symbolic links yet the setting is not dynamic meaning you have to restart mysqld to change the setting. This is intrusive.

myuser@myhost [(none)]> set global have_symlink = 1;
ERROR 1238 (HY000): Variable 'have_symlink' is a read only variable

The configuration settings are also somewhat confusing.

SHOW VARIABLES SHOWS or similar shows:

myuser@myserver [(none)]> select @@have_symlink, @@version;
+----------------+------------+
| @@have_symlink | @@version  |
+----------------+------------+
| DISABLED       | 5.6.33-log |
+----------------+------------+
1 row in set (0.00 sec)

yet the configuration name in /etc/my.cnf shows:

[myuser@myhost ~]$ grep sym /etc/my.cnf
symbolic-links=0

This is somewhat confusing.

How to repeat:
See instructions.

Try to change the value and see what happens.

Suggested fix:

1. Please make this configuration setting dynamic.
2. Please use the same configuration variable in SHOW GLOBAL VARIABLES compared to /etc/my.cnf.

[24 Nov 2016 8:01] MySQL Verification Team

Hello Simon,

Thank you for the feature request and feedback!

Thanks,
Umesh