Hello,
I'm currently developing a usermode input driver using uinput.
While doing this, I've found some "ugly" behaviour.
If I do getfacl from my regular user, I get:
$ getfacl /dev/uinput
getfacl: Removing leading '/' from absolute path names
# file: dev/uinput
# owner: root
# group: root
user::rw-
user:manuel:rw-
group::---
mask::rw-
other::---
So for whatever reason my user is able to launch a usermode input
driver. No root permission needed.
But in fact the driver isn't even loaded (no uinput module). But it is
loaded as soon as I try to access the device. After that, I have:
$ getfacl /dev/uinput
getfacl: Removing leading '/' from absolute path names
# file: dev/uinput
# owner: root
# group: root
user::rw-
user:manuel:rw- #effective:---
group::---
mask::---
other::---
So somehow the permission is still there, but no longer effective???
If I switch VT once (and probably switching the active session this way)
I have permission again and now my user keeps it.
What is causing this ugly behaviour? Why does a user have to have uinput
permissions at all? The (possible security) problem with this is, that
the driver (may be a simulated keyboard driver) keeps active even if the
session changes. So a software, launched in one session, affects another
session.
Thanks in advance
Manuel
