selftests/bpf: add a test for device cgroup controller

2017-11-05T14:26:51Z

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 Acked-by: Alexei Starovoitov Acked-by: Tejun Heo Cc: Daniel Borkmann Signed-off-by: David S. Miller

kernel/tools/testing/selftests/bpf/dev_cgroup.c, branch linux-4.16.y

selftests/bpf: add a test for device cgroup controller