diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/read_cgroupfs_xattr.c')
-rw-r--r-- | tools/testing/selftests/bpf/progs/read_cgroupfs_xattr.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/read_cgroupfs_xattr.c b/tools/testing/selftests/bpf/progs/read_cgroupfs_xattr.c new file mode 100644 index 000000000000..855f85fc5522 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/read_cgroupfs_xattr.c @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2025 Meta Platforms, Inc. and affiliates. */ + +#include <vmlinux.h> +#include <bpf/bpf_tracing.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_core_read.h> +#include "bpf_experimental.h" + +char _license[] SEC("license") = "GPL"; + +pid_t target_pid = 0; + +char xattr_value[64]; +static const char expected_value_a[] = "bpf_selftest_value_a"; +static const char expected_value_b[] = "bpf_selftest_value_b"; +bool found_value_a; +bool found_value_b; + +SEC("lsm.s/socket_connect") +int BPF_PROG(test_socket_connect) +{ + u64 cgrp_id = bpf_get_current_cgroup_id(); + struct cgroup_subsys_state *css, *tmp; + struct bpf_dynptr value_ptr; + struct cgroup *cgrp; + + if ((bpf_get_current_pid_tgid() >> 32) != target_pid) + return 0; + + bpf_rcu_read_lock(); + cgrp = bpf_cgroup_from_id(cgrp_id); + if (!cgrp) { + bpf_rcu_read_unlock(); + return 0; + } + + css = &cgrp->self; + bpf_dynptr_from_mem(xattr_value, sizeof(xattr_value), 0, &value_ptr); + bpf_for_each(css, tmp, css, BPF_CGROUP_ITER_ANCESTORS_UP) { + int ret; + + ret = bpf_cgroup_read_xattr(tmp->cgroup, "user.bpf_test", + &value_ptr); + if (ret < 0) + continue; + + if (ret == sizeof(expected_value_a) && + !bpf_strncmp(xattr_value, sizeof(expected_value_a), expected_value_a)) + found_value_a = true; + if (ret == sizeof(expected_value_b) && + !bpf_strncmp(xattr_value, sizeof(expected_value_b), expected_value_b)) + found_value_b = true; + } + + bpf_rcu_read_unlock(); + bpf_cgroup_release(cgrp); + + return 0; +} |