What are the advantages for updating so often?
Here is a list why packages (so including the kernel) got updated: https://www.ubuntuupdates.org/
- Version: 3.5.0-22.34 2013-01-08 23:19:18 UTC
- Version: 3.5.0-22.33 2013-01-02 23:08:48 UTC
- Version: 3.5.0-21.32 2012-12-11 21:08:43 UTC
- Version: 3.5.0-20.31 2012-12-05 15:08:46 UTC
- Version: 3.5.0-19.30 2012-11-13 19:08:30 UTC
All include a long list of fixes so the best answer to me seems: those kernel bug fixers have been doing a lot of work so there have been more moments to offer a kernel upgrade.
It might have something to do with the kenelversion 3.5.0. This was a big update so it will include a bit more bugs where some might be easy to fix.
The main reason is to provide fixes to security flaws that get discovered, fix stability bugs, and provide updated hardware support.
Some notes about kernel updates:
Because the running kernel is kept loaded in memory, it possible to keep working indefinitely without rebooting after a kernel update. This will continue running the old kernel. Of course, you will then remain vulnerable to any security issues fixed in the update until you reboot. If you are just using a low-security workstation and you're in the middle of something, that risk may be acceptable. Consider reading the changelog for the update to see whether it contains security fixes for flaws that may affect you.
Ksplice is a kernel extension that allows the running kernel to be updated in memory, without rebooting. This is useful for servers for which downtime (disruptions when rebooting) is costly.
Frequent updates may not always be an advantage but as far as security goes, it is. If some kind of weakness is found in the kernel it could potentially be used to compromise the system until it is fixed. So it's best if as little time as possible passes from the discovery of a security hole until it's been fixed. There's really no reason to wait and leave an open security hole while there's a perfectly good fix available.
It's good to always have the latest kernel. Even if there's no security problem, an update might fix a bug or improve stability. And of course, new features are nice.
All code has bugs. So does linux kernel code. Kernel updates fix kernel bugs early, before there is a zero-day exploit.
If you update, you are a moving target for an attacker. If you update on time, you move faster than any anyone can point. This makes you more or less safe from viruses and trojans.