Why do I get contradicting Ubuntu versions?

Solution 1:

Let's break-down your issue into two parts:

1. Your current Ubuntu version from the output of /etc/apt/sources.list

2. Your current Ubuntu version from the output of everything else.

Now, to the explanation:

1. From Ubuntu.

   The only lines that gets upgraded in that file are the lines that starts with deb, deb-src, #deb or #deb-src because

   Ubuntu uses apt for package management. Apt stores a list of repositories or software channels in the file.

   If there are any other lines in the file that are uncommented and doesn't start with deb, etc. then the command sudo apt-get update will produce errors.

   But the main part relevant to you is that the file doesn't get updated as a whole but the lines in them that are stated above. So, the file is basically the same one as the time when you installed Ubuntu and to make it more clear you installed Ubuntu 12.04.1 LTS to start with and upgraded your way to 12.04.5 LTS.

2. Now, for the second part,

   From lsb-release --help:

   -v, --version      show LSB modules this system supports
   -u, --upstream     show upstream LSB data
   -i, --id           show distributor ID
   -d, --description  show description of this distribution
   -r, --release      show release number of this distribution
   -c, --codename     show code name of this distribution
   -a, --all          show all of the above information
   

   i.e., the command lsb_release -a gives you the exact information as to what your current version of Ubuntu is.

Also about your other question regarding kernels, the latest kernel that is available for Precise is 3.13.*. So, everything's fine with your Ubuntu. But on another note if you want to install the more latest kernels on your current version then you might want to follow this YouTube.

EDIT: As Pilot6 pointed out and from Ubuntu Wiki in 12.04.x Ubuntu Kernel Support section:

It seems that 12.04.5 has kernel version 3.13.*.

Solution 2:

You are using Ubuntu 12.04.5. It is updated 12.04 release.

But HWE Stack including kernels and X.org is not updated automatically.

I see no problems or bugs that can be reported.