SYSTEM WARNING: 'date_default_timezone_get(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone.' in '/usr/share/mantis/www/core.php' line 264

0002644: synchronization issues in endian.core.notification module - MantisBT

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Project

Category

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Date Submitted

Last Update

0002644

Endian Firewall

Other Scripts

public

2010-01-28 14:28

2010-09-21 18:33

Reporter

peter-endian

Assigned To

Priority

normal

Severity

minor

Reproducibility

random

Status

confirmed

Resolution

open

Platform

OS Version

Product Version

Target Version

future

Fixed in Version

Summary

0002644: synchronization issues in endian.core.notification module

Description

StatusFileMutex.__init__() removes the mutex file if it does already exist
StatusFile.close() removes the mutex file after releasing the lock.

what if another process (B) acquired a lock on the mutex file held by process A? That process stored already the filehandle and blocks until A releases. When process C removes the file, before acquire(), C can create a new file which is not more blocked by A. The file blocked by A is removed from the filesystem, but the filedescriptor is still open and A can write to it.

When A closes that filedescriptor, process B will be able to open it and continue operations on it. But that is not more the same file as we see in the filesystem.

In that case 2 processes with the same lockfile are running but only 1 lockfile is visible in filesystem.

That's no mutex

Issue History
Date Modified	Username	Field	Change
2010-01-28 14:28	peter-endian	New Issue
2010-09-21 18:33	peter-endian	Status	new => confirmed

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