pyOpenSSL and invalid certificates

I was trying to import some X509v3 certificates that were created with pyOpenSSL to a MikroTik router (RouterOS 6.1) but they were always being imported with an invalid validity period (not before 1970 and not after 1970). Eventually I found out that this is because pyOpenSSL stores the validity field in an invalid format. Here’s …

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Quick fix for X.org screensaver bypass

This vulnerability is quite annoying if you’re locking your desktop in work or anywhere else. In short, one is able to kill xorg’s xscreensaver’s lock by just pressing alt-ctrl-* or alt-ctrl-/ (both * and / need to be from the keypad). A workaround that was posted suggests to modify files in the system. If you …

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fix for radeon + opensource driver + kde effects = crash

The problem Kwin crashes when enabling opengl effects. It doesn’t crash immediately but it crashes after specific actions so it is 100% reproducible. For example when exiting from desktop-grid effect. The situation I’m using: Radeon 4870 graphics card (RV770) Kernel 3.1.5 (but seems irrelevant) Open source ATI driver with KMS using Gallium Xorg 1.11.2.902 (but …

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Big nfs_inode_cache

The story Boxes with various kernel versions have weird free memory problems. After examining the memory usage it seems that processes don’t add up to the actual memory that is being used. Taking a look at /proc/meminfo we see something like this: Notice that Slab is about 7.5GB, almost the whole memory (8GB) (!). Slab …

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php foreach by reference

Here’s an interesting “feature” (bug?) for php. Recent PHP versions support this syntax for foreach: foreach ($myarray as &$v) $v[‘koko’]=’lala’; This allows easy changes to the actual table by using references and not acting on a copy. – but – If you do this: $myarray=array(array(‘a’=>1), array(‘a’=>2), array(‘a’=>3)); foreach ($myarray as &$v) $v[‘b’]=1; foreach ($myarray as …

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