From 360769233cc9c921e90ae387d167ea3cd3cbb04c Mon Sep 17 00:00:00 2001 From: Yafang Shao Date: Sat, 11 Nov 2023 09:00:34 +0000 Subject: [PATCH] selftests/bpf: Add selftests for cgroup1 hierarchy Add selftests for cgroup1 hierarchy. The result as follows, $ tools/testing/selftests/bpf/test_progs --name=cgroup1_hierarchy #36/1 cgroup1_hierarchy/test_cgroup1_hierarchy:OK #36/2 cgroup1_hierarchy/test_root_cgid:OK #36/3 cgroup1_hierarchy/test_invalid_level:OK #36/4 cgroup1_hierarchy/test_invalid_cgid:OK #36/5 cgroup1_hierarchy/test_invalid_hid:OK #36/6 cgroup1_hierarchy/test_invalid_cgrp_name:OK #36/7 cgroup1_hierarchy/test_invalid_cgrp_name2:OK #36/8 cgroup1_hierarchy/test_sleepable_prog:OK #36 cgroup1_hierarchy:OK Summary: 1/8 PASSED, 0 SKIPPED, 0 FAILED Besides, I also did some stress test similar to the patch #2 in this series, as follows (with CONFIG_PROVE_RCU_LIST enabled): - Continuously mounting and unmounting named cgroups in some tasks, for example: cgrp_name=$1 while true do mount -t cgroup -o none,name=$cgrp_name none /$cgrp_name umount /$cgrp_name done - Continuously run this selftest concurrently, while true; do ./test_progs --name=cgroup1_hierarchy; done They can ran successfully without any RCU warnings in dmesg. Signed-off-by: Yafang Shao Link: https://lore.kernel.org/r/20231111090034.4248-7-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov --- .../bpf/prog_tests/cgroup1_hierarchy.c | 158 ++++++++++++++++++ .../bpf/progs/test_cgroup1_hierarchy.c | 71 ++++++++ 2 files changed, 229 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/cgroup1_hierarchy.c create mode 100644 tools/testing/selftests/bpf/progs/test_cgroup1_hierarchy.c diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup1_hierarchy.c b/tools/testing/selftests/bpf/prog_tests/cgroup1_hierarchy.c new file mode 100644 index 00000000000000..74d6d7546f40fa --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/cgroup1_hierarchy.c @@ -0,0 +1,158 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2023 Yafang Shao */ + +#include +#include +#include +#include "cgroup_helpers.h" +#include "test_cgroup1_hierarchy.skel.h" + +static void bpf_cgroup1(struct test_cgroup1_hierarchy *skel) +{ + struct bpf_link *lsm_link, *fentry_link; + int err; + + /* Attach LSM prog first */ + lsm_link = bpf_program__attach_lsm(skel->progs.lsm_run); + if (!ASSERT_OK_PTR(lsm_link, "lsm_attach")) + return; + + /* LSM prog will be triggered when attaching fentry */ + fentry_link = bpf_program__attach_trace(skel->progs.fentry_run); + ASSERT_NULL(fentry_link, "fentry_attach_fail"); + + err = bpf_link__destroy(lsm_link); + ASSERT_OK(err, "destroy_lsm"); +} + +static void bpf_cgroup1_sleepable(struct test_cgroup1_hierarchy *skel) +{ + struct bpf_link *lsm_link, *fentry_link; + int err; + + /* Attach LSM prog first */ + lsm_link = bpf_program__attach_lsm(skel->progs.lsm_s_run); + if (!ASSERT_OK_PTR(lsm_link, "lsm_attach")) + return; + + /* LSM prog will be triggered when attaching fentry */ + fentry_link = bpf_program__attach_trace(skel->progs.fentry_run); + ASSERT_NULL(fentry_link, "fentry_attach_fail"); + + err = bpf_link__destroy(lsm_link); + ASSERT_OK(err, "destroy_lsm"); +} + +static void bpf_cgroup1_invalid_id(struct test_cgroup1_hierarchy *skel) +{ + struct bpf_link *lsm_link, *fentry_link; + int err; + + /* Attach LSM prog first */ + lsm_link = bpf_program__attach_lsm(skel->progs.lsm_run); + if (!ASSERT_OK_PTR(lsm_link, "lsm_attach")) + return; + + /* LSM prog will be triggered when attaching fentry */ + fentry_link = bpf_program__attach_trace(skel->progs.fentry_run); + if (!ASSERT_OK_PTR(fentry_link, "fentry_attach_success")) + goto cleanup; + + err = bpf_link__destroy(fentry_link); + ASSERT_OK(err, "destroy_lsm"); + +cleanup: + err = bpf_link__destroy(lsm_link); + ASSERT_OK(err, "destroy_fentry"); +} + +void test_cgroup1_hierarchy(void) +{ + struct test_cgroup1_hierarchy *skel; + __u64 current_cgid; + int hid, err; + + skel = test_cgroup1_hierarchy__open(); + if (!ASSERT_OK_PTR(skel, "open")) + return; + + skel->bss->target_pid = getpid(); + + err = bpf_program__set_attach_target(skel->progs.fentry_run, 0, "bpf_fentry_test1"); + if (!ASSERT_OK(err, "fentry_set_target")) + goto destroy; + + err = test_cgroup1_hierarchy__load(skel); + if (!ASSERT_OK(err, "load")) + goto destroy; + + /* Setup cgroup1 hierarchy */ + err = setup_classid_environment(); + if (!ASSERT_OK(err, "setup_classid_environment")) + goto destroy; + + err = join_classid(); + if (!ASSERT_OK(err, "join_cgroup1")) + goto cleanup; + + current_cgid = get_classid_cgroup_id(); + if (!ASSERT_GE(current_cgid, 0, "cgroup1 id")) + goto cleanup; + + hid = get_cgroup1_hierarchy_id("net_cls"); + if (!ASSERT_GE(hid, 0, "cgroup1 id")) + goto cleanup; + skel->bss->target_hid = hid; + + if (test__start_subtest("test_cgroup1_hierarchy")) { + skel->bss->target_ancestor_cgid = current_cgid; + bpf_cgroup1(skel); + } + + if (test__start_subtest("test_root_cgid")) { + skel->bss->target_ancestor_cgid = 1; + skel->bss->target_ancestor_level = 0; + bpf_cgroup1(skel); + } + + if (test__start_subtest("test_invalid_level")) { + skel->bss->target_ancestor_cgid = 1; + skel->bss->target_ancestor_level = 1; + bpf_cgroup1_invalid_id(skel); + } + + if (test__start_subtest("test_invalid_cgid")) { + skel->bss->target_ancestor_cgid = 0; + bpf_cgroup1_invalid_id(skel); + } + + if (test__start_subtest("test_invalid_hid")) { + skel->bss->target_ancestor_cgid = 1; + skel->bss->target_ancestor_level = 0; + skel->bss->target_hid = -1; + bpf_cgroup1_invalid_id(skel); + } + + if (test__start_subtest("test_invalid_cgrp_name")) { + skel->bss->target_hid = get_cgroup1_hierarchy_id("net_cl"); + skel->bss->target_ancestor_cgid = current_cgid; + bpf_cgroup1_invalid_id(skel); + } + + if (test__start_subtest("test_invalid_cgrp_name2")) { + skel->bss->target_hid = get_cgroup1_hierarchy_id("net_cls,"); + skel->bss->target_ancestor_cgid = current_cgid; + bpf_cgroup1_invalid_id(skel); + } + + if (test__start_subtest("test_sleepable_prog")) { + skel->bss->target_hid = hid; + skel->bss->target_ancestor_cgid = current_cgid; + bpf_cgroup1_sleepable(skel); + } + +cleanup: + cleanup_classid_environment(); +destroy: + test_cgroup1_hierarchy__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_cgroup1_hierarchy.c b/tools/testing/selftests/bpf/progs/test_cgroup1_hierarchy.c new file mode 100644 index 00000000000000..44628865fe1d48 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_cgroup1_hierarchy.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2023 Yafang Shao */ + +#include "vmlinux.h" +#include +#include +#include + +__u32 target_ancestor_level; +__u64 target_ancestor_cgid; +int target_pid, target_hid; + +struct cgroup *bpf_task_get_cgroup1(struct task_struct *task, int hierarchy_id) __ksym; +struct cgroup *bpf_cgroup_ancestor(struct cgroup *cgrp, int level) __ksym; +void bpf_cgroup_release(struct cgroup *cgrp) __ksym; + +static int bpf_link_create_verify(int cmd) +{ + struct cgroup *cgrp, *ancestor; + struct task_struct *task; + int ret = 0; + + if (cmd != BPF_LINK_CREATE) + return 0; + + task = bpf_get_current_task_btf(); + + /* Then it can run in parallel with others */ + if (task->pid != target_pid) + return 0; + + cgrp = bpf_task_get_cgroup1(task, target_hid); + if (!cgrp) + return 0; + + /* Refuse it if its cgid or its ancestor's cgid is the target cgid */ + if (cgrp->kn->id == target_ancestor_cgid) + ret = -1; + + ancestor = bpf_cgroup_ancestor(cgrp, target_ancestor_level); + if (!ancestor) + goto out; + + if (ancestor->kn->id == target_ancestor_cgid) + ret = -1; + bpf_cgroup_release(ancestor); + +out: + bpf_cgroup_release(cgrp); + return ret; +} + +SEC("lsm/bpf") +int BPF_PROG(lsm_run, int cmd, union bpf_attr *attr, unsigned int size) +{ + return bpf_link_create_verify(cmd); +} + +SEC("lsm.s/bpf") +int BPF_PROG(lsm_s_run, int cmd, union bpf_attr *attr, unsigned int size) +{ + return bpf_link_create_verify(cmd); +} + +SEC("fentry") +int BPF_PROG(fentry_run) +{ + return 0; +} + +char _license[] SEC("license") = "GPL";