selftests/bpf: add a test for device cgroup controller

Add a test for device cgroup controller.

The test loads a simple bpf program which logs all
device access attempts using trace_printk() and forbids
all operations except operations with /dev/zero and
/dev/urandom.

Then the test creates and joins a test cgroup, and attaches
the bpf program to it.

Then it tries to perform some simple device operations
and checks the result:

  create /dev/null (should fail)
  create /dev/zero (should pass)
  copy data from /dev/urandom to /dev/zero (should pass)
  copy data from /dev/urandom to /dev/full (should fail)
  copy data from /dev/random to /dev/zero (should fail)

Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Alexei Starovoitov <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

0 files changed, 0 insertions, 0 deletions