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

selftests/bpf: fix test_dev_cgroup

2018-01-23T17:42:12Z

The test incorrectly doing mkdir /mnt/cgroup-test-work-dirtest-bpf-based-device-cgroup instead of mkdir /mnt/cgroup-test-work-dir/test-bpf-based-device-cgroup somehow such mkdir succeeds and new directory appears: /mnt/cgroup-test-work-dir/cgroup-test-work-dirtest-bpf-based-device-cgroup Later cleanup via nftw("/mnt/cgroup-test-work-dir", ...); doesn't walk this directory. "rmdir /mnt/cgroup-test-work-dir" succeeds, but bpf program and dangling cgroup stays in memory. That's a separate issue on a cgroup side. For now fix the test. Fixes: 37f1ba0909df ("selftests/bpf: add a test for device cgroup controller") Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann

tools/bpf: adjust rlimit RLIMIT_MEMLOCK for test_dev_cgroup

2017-12-21T03:15:54Z

The default rlimit RLIMIT_MEMLOCK is 64KB. In certain cases, e.g. in a test machine mimicking our production system, this test may fail due to unable to charge the required memory for prog load: $ ./test_dev_cgroup libbpf: load bpf program failed: Operation not permitted libbpf: failed to load program 'cgroup/dev' libbpf: failed to load object './dev_cgroup.o' Failed to load DEV_CGROUP program ... Changing the default rlimit RLIMIT_MEMLOCK to unlimited makes the test pass. This patch also fixed a problem where when bpf_prog_load fails, cleanup_cgroup_environment() should not be called since setup_cgroup_environment() has not been invoked. Otherwise, the following confusing message will appear: ... (/home/yhs/local/linux/tools/testing/selftests/bpf/cgroup_helpers.c:95: errno: No such file or directory) Opening Cgroup Procs: /mnt/cgroup.procs ... Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov

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