Testing with permissive domains

When testing out new technologies or new setups, not having (proper) SELinux policies can be a nuisance. Not only are the number of SELinux policies that are available through the standard repositories limited, some of these policies are not even written with the same level of confinement that an administrator might expect. Or perhaps the technology to be tested is used in a completely different manner.

Without proper policies, any attempt to start such a daemon or application might or will cause permission violations. In many cases, developers or users tend to disable SELinux enforcing then so that they can continue playing with the new technology. And why not? After all, policy development is to be done after the technology is understood.

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Audit buffering and rate limiting

Be it because of SELinux experiments, or through general audit experiments, sometimes you'll get in touch with a message similar to the following:

audit: audit_backlog=321 > audit_backlog_limit=320
audit: audit_lost=44395 audit_rate_limit=0 audit_backlog_limit=320
audit: backlog limit exceeded

The message shows up when certain audit events could not be …

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CIL and attributes

I keep on struggling to remember this, so let's make a blog post out of it ;-)

When the SELinux policy is being built, recent userspace (2.4 and higher) will convert the policy into CIL language, and then build the binary policy. When the policy supports type attributes, these are …

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Have dhcpcd wait before backgrounding

Many of my systems use DHCP for obtaining IP addresses. Even though they all receive a static IP address, it allows me to have them moved over (migrations), use TFTP boot, cloning (in case of quick testing), etc. But one of the things that was making my efforts somewhat more …

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SELinux is great for enterprises (but many don't know it yet)

Large companies that handle their own IT often have internal support teams for many of the technologies that they use. Most of the time, this is for reusable components like database technologies, web application servers, operating systems, middleware components (like file transfers, messaging infrastructure, ...) and more. All components that are …

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