Posts by admin

Alert: Bash Code Injection Vulnerability

- by admin

This is really serious: Red Hat Product Security has been made aware of a vulnerability affecting all versions of the Bash package shipped with Red Hat Enterprise Linux. Since many of Red Hat's products run on a base installation of Red Hat Enteprise Linux, there is a risk of other products being impacted by this vulnerability as well.

The same issue found in Debian 6 & 7...

In order to test if your version of Bash is vulnerable to this issue, run the following command:

$ env x='() { :;}; echo vulnerable'  bash -c "echo this is a test"

If the output of the above command looks as follows:

vulnerable<br />
this is a test

you are using a vulnerable version of Bash. The patch used to fix this issue ensures that no code is allowed after the end of a Bash function. Thus, if you run the above example with the patched version of Bash, you should get an output similar to:

$ env x='() { :;}; echo vulnerable'  bash -c "echo this is a test"<br />
bash: warning: x: ignoring function definition attempt<br />
bash: error importing function definition for `x'<br />
this is a test

So, UPDATE ASAP! yum update; apt-get upgrade - just do it regularry - every day, just as having coffee :-)

Can Bender bend an iPhone6 Plus?

- by admin

YES! He can. Even not Bender but you - just look how to do it.

According to experts, though, it probably shouldn't be surprising. As Jeremy Irons, a Design Engineer at Creative Engineering explained:

From an engineering standpoint, the iPhone is an amazingly small and delicately constructed device. The only thing really contributing to the structural integrity of the iPhone 6 Plus is the thin aluminum frame that covers the back and reaches around the sides. There is also another very thin piece of steel behind the glass, but we are not working with much as far as bending strength.

iOS 7 Functions Compatibility Matrix

- by admin

iOS 7, the latest version of Apple's mobile operating system, is now available for download. The update can be installed on any compatible iPhone, iPad, or iPod touch by visiting your device's settings menu, choosing "general," and then selecting the software update option. iOS 7 can also be installed with the help of the newly-released iTunes 11.1 on Windows and OS X. (You'll want to download that anyway, as it's required to sync music, videos, and other content to your device.)

The most immediate and striking change in Apple's latest OS is the all-new user interface designed under the eye of Jony Ive. iOS has been given a comprehensive visual makeover intended to make the overall user experience "simpler, more useful, and more enjoyable." But changes aren't just skin deep; iOS 7 introduces new features like iTunes Radio, AirDrop sharing, Control Center, and improved card-style multitasking.

Note that not all of Apple's latest features are available across all iOS hardware. If you're running the new software on anything older than an iPhone 5 or iPad 4, you stand to lose out on some functionality. Please find below those differences matrix.

New file in Mac OS X Finder

- by admin

Sometimes we need to create a file from Finder directly. And this is strange that Finder allows easily to create a folder but not a file! Although Linux and Windows file browsers have this option. So, let's enhance Finder!

First start Automator (Launchpad / Other / Automator). In the chooser that appears next, select Service.

At the top of the Automator main window, set the "Service Receives Selected" drop-down to "files or folders". Then select Library / Utilities in the left tree menu. Next drag (or just double click) "Run AppleScript" into the main working area (mid-right). Here you will get "Run AppleScript" box. Paste the following AppleScript into this code box, then click the hammer icon to compile the code:
on run {input, parameters}
tell application "Finder"
set currentPath to insertion location as text
set x to POSIX path of currentPath
end tell
return x
end run

Next double click on "Set Value of a Variable" (also in the LIbrary / Utilities section). Click the "Variable" drop-down and create a new variable. Let's call it currentFolder.

Select Library / Text in the left tree menu. Next drag (or just double click) "New Text File" into the main working area (mid-right). Here you will get "New Text File" box.

Drag the variable you just created (currentFolder) from the Variable panel at the bottom of the Automator window to the "Where" selector of the "New Text File" action. Change "Encoding" to "Unicode (UTF-8)". Click the New Text File's "Options" button (at the bottom of the box) and select "Show this action when the workflow runs". This will allow you to specify the names of new files.

Save the service with "File / Save ..." top menu and give it a name (For example "New File"). To test it, in the Finder go to the folder where you want to create a new file. Control-click on an existing file within that folder and select "New File" from the "Services" submenu. A dialog should appear requesting a filename. Enter one then click "Continue"; your new file should appear.

This obviously creates a text or RTF empty file (file with .txt or .rtf extension). You can change the extension to whatever you need as the last step.

SQL Joins Diagram

- by admin

For those who love SQL :-)

Source: Data Visualisation

MySQL innodb_buffer_pool_size optimal value

- by admin

innodb_buffer_pool_size is a quite important MySQL configuration parameter which can dramatically increase your DB productivity. The larger you set this value, the less disk I/O is needed to access data in tables. Just today I have got one of a heavy SQL query time changed from 15.5 to 1.2 seconds by changing innodb_buffer_pool_size from 23M to 320M! On a dedicated database server, you may set this to up to 80% of the machine physical memory size. Of course, you need to be careful with memory consumption, especially for a non-dedicated server.

To get optimal value of innodb_buffer_pool_size for your DB you may run this SQL:
SELECT CEILING(Total_InnoDB_Bytes*1.6/POWER(1024,3)) RIBPS
FROM (SELECT SUM(data_length+index_length) Total_InnoDB_Bytes
FROM information_schema.tables WHERE engine='InnoDB') A;

It would return optimal size calculated as sum of DB stored data and indexes multiple by 1.6. But it does not know anything about you physical memory! Thus set innodb_buffer_pool_size not more than 15% of RAM size. To test how much memory your new configured MySQL would maximum consume, use this mysqltuner Perl script. You can also use this script for optimizing of your MySQL DB other settings.

The last but not the least: innodb_buffer_pool_size has to be put in mysqld section of you MySQL configuration file (/etc/my.conf in RHEL):

HTTP Error 400: Size of a request header field exceeds server limit

- by admin

I have got an error generated by Apache while configuring Plexcel (PHP Active Directory module):
Error 400: Your browser sent a request that this server could not understand.
Size of a request header field exceeds server limit.

The solution was an easy one: to increase allowed request field size in Apache configuration (/etc/httpd/conf/httpd.conf for RHEL):
LimitRequestFieldSize 16380

Just for information: the default value for LimitRequestFieldSize is equal to 8190.

If you cannot change server settings just try to clean up your browser cookies and limit the size of cookies stored in your browser. It may prevent your browser to send too big request.


Google Chrome Spell Check - crazy message after update

- by admin

I have updated Google Chrome on Red Hat Linux. And to my surprise after restarting Google Chrome I got this:

Google crazy hint







"bettar spell chek" - o la la!

The first idea: maybe there is a problem with my Linux box? But trying Chrome update on Mac and Windows I have got the same results!

I guess they did it on purpose. Just imagine how many Chrome new downloads would be soon!


NetBeans 7.3: Cannot execute Google Chrome

- by admin

I have got today an error in NetBeans 7.3 while starting a HTML5 application in Google Chrome:
Cannot execute /opt/google/chrome/chrome.
Check external browser configuration.

The solution was simple: just change Chrome in Tools / Options / General / Web Browser to

Voilà :-)


How to check DNS cache status in Mac OS X

- by admin

As a follow-up to How to Flush DNS Cache in Mac OS X I have received a question:

how do I know if it worked? In other words, is there a way to check if the DNS cache is cleared?

To see the DNS cache status you may run
sudo killall -INFO mDNSResponder

Thus the SIGINFO signal will dump a snapshot summary of the DNS internal state to

Voilà :-)


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