Messages in this thread | | | Date | Thu, 1 Apr 1999 22:04:50 -0500 | Subject | Re: ext3 to include capabilities? | From | tytso@mit ... |
| |
From: alan@lxorguk.ukuu.org.uk (Alan Cox) Date: Fri, 2 Apr 1999 00:02:16 +0100 (BST)
> 1. Put capabilities information in the executable header. > 2. Mark the executable setuid root. > 3. Have the kernel check for #1 if #2, and prefer #1 if present.
That confuses everyones security scripts. It makes the binary run as root on an older system, so if you downgrade you get a massive security hole
Actually, that's not the worst of the problem. If the capabilities information is in the executable header, then it can be edited by the owner of the file. This is *not* a good thing --- think of capabilities as some of the various privileges of root split into separate privileges. For example, the right to open a port below 1024, the right to bypass filesystem access control checks, etc. The ability to edit capabilities *must* be reserved to the kernel, and by putting it into the executable header, it's subject to be edited by anyone with write access to the file.
- Ted
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
| |