[debian-mysql] Bug#527623: mysql-server-5.0: 38_scripts__mysqld_safe.sh__signals.dpatch is inherently broken

[Mario Limonciello]

Package: mysql-server-5.0
Version: 5.0.81-1
Severity: important

Currently 38_scripts__mysqld_safe.sh__signals.dpatch adds features to mysqld_safe to attempt to support traps for mysqld_safe.

Unfortunately, it's implementation is not proper.  Here's the scenario that actually happens:

1) essentially, "mysqld & wait" is running
So mysqld is running in the background, and the bash script is blocked by
the wait command.
2) the trap comes in and causes wait to exit a status higher than 128 (look at bash manpage)
3) the refresh is issued to mysqld via mysqldadmin
3) the bash script continues and runs kill -9 mysqld as it thinks that mysqld is hung now

Any applications that had open connections at this time will have those connections severed causing unexpected behaviors on
the system


-- System Information:
Debian Release: 5.0
  APT prefers jaunty-updates
  APT policy: (500, 'jaunty-updates'), (500, 'jaunty-security'), (500, 'jaunty-proposed'), (500, 'jaunty-backports'), (500, 'jaunty')
Architecture: i386 (i686)

Kernel: Linux 2.6.28-11-generic (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash