1 files changed, 158 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/cgroup_read_xattr.c b/tools/testing/selftests/bpf/progs/cgroup_read_xattr.c
new file mode 100644
index 000000000000..092db1d0435e
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/cgroup_read_xattr.c
@@ -0,0 +1,158 @@
+// 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"
+#include "bpf_misc.h"
+
+char _license[] SEC("license") = "GPL";
+
+char value[16];
+
+static __always_inline void read_xattr(struct cgroup *cgroup)
+{
+	struct bpf_dynptr value_ptr;
+
+	bpf_dynptr_from_mem(value, sizeof(value), 0, &value_ptr);
+	bpf_cgroup_read_xattr(cgroup, "user.bpf_test",
+			      &value_ptr);
+}
+
+SEC("lsm.s/socket_connect")
+__success
+int BPF_PROG(trusted_cgroup_ptr_sleepable)
+{
+	u64 cgrp_id = bpf_get_current_cgroup_id();
+	struct cgroup *cgrp;
+
+	cgrp = bpf_cgroup_from_id(cgrp_id);
+	if (!cgrp)
+		return 0;
+
+	read_xattr(cgrp);
+	bpf_cgroup_release(cgrp);
+	return 0;
+}
+
+SEC("lsm/socket_connect")
+__success
+int BPF_PROG(trusted_cgroup_ptr_non_sleepable)
+{
+	u64 cgrp_id = bpf_get_current_cgroup_id();
+	struct cgroup *cgrp;
+
+	cgrp = bpf_cgroup_from_id(cgrp_id);
+	if (!cgrp)
+		return 0;
+
+	read_xattr(cgrp);
+	bpf_cgroup_release(cgrp);
+	return 0;
+}
+
+SEC("lsm/socket_connect")
+__success
+int BPF_PROG(use_css_iter_non_sleepable)
+{
+	u64 cgrp_id = bpf_get_current_cgroup_id();
+	struct cgroup_subsys_state *css;
+	struct cgroup *cgrp;
+
+	cgrp = bpf_cgroup_from_id(cgrp_id);
+	if (!cgrp)
+		return 0;
+
+	bpf_for_each(css, css, &cgrp->self, BPF_CGROUP_ITER_ANCESTORS_UP)
+		read_xattr(css->cgroup);
+
+	bpf_cgroup_release(cgrp);
+	return 0;
+}
+
+SEC("lsm.s/socket_connect")
+__failure __msg("expected an RCU CS")
+int BPF_PROG(use_css_iter_sleepable_missing_rcu_lock)
+{
+	u64 cgrp_id = bpf_get_current_cgroup_id();
+	struct cgroup_subsys_state *css;
+	struct cgroup *cgrp;
+
+	cgrp = bpf_cgroup_from_id(cgrp_id);
+	if (!cgrp)
+		return 0;
+
+	bpf_for_each(css, css, &cgrp->self, BPF_CGROUP_ITER_ANCESTORS_UP)
+		read_xattr(css->cgroup);
+
+	bpf_cgroup_release(cgrp);
+	return 0;
+}
+
+SEC("lsm.s/socket_connect")
+__success
+int BPF_PROG(use_css_iter_sleepable_with_rcu_lock)
+{
+	u64 cgrp_id = bpf_get_current_cgroup_id();
+	struct cgroup_subsys_state *css;
+	struct cgroup *cgrp;
+
+	bpf_rcu_read_lock();
+	cgrp = bpf_cgroup_from_id(cgrp_id);
+	if (!cgrp)
+		goto out;
+
+	bpf_for_each(css, css, &cgrp->self, BPF_CGROUP_ITER_ANCESTORS_UP)
+		read_xattr(css->cgroup);
+
+	bpf_cgroup_release(cgrp);
+out:
+	bpf_rcu_read_unlock();
+	return 0;
+}
+
+SEC("lsm/socket_connect")
+__success
+int BPF_PROG(use_bpf_cgroup_ancestor)
+{
+	u64 cgrp_id = bpf_get_current_cgroup_id();
+	struct cgroup *cgrp, *ancestor;
+
+	cgrp = bpf_cgroup_from_id(cgrp_id);
+	if (!cgrp)
+		return 0;
+
+	ancestor = bpf_cgroup_ancestor(cgrp, 1);
+	if (!ancestor)
+		goto out;
+
+	read_xattr(cgrp);
+	bpf_cgroup_release(ancestor);
+out:
+	bpf_cgroup_release(cgrp);
+	return 0;
+}
+
+SEC("cgroup/sendmsg4")
+__success
+int BPF_PROG(cgroup_skb)
+{
+	u64 cgrp_id = bpf_get_current_cgroup_id();
+	struct cgroup *cgrp, *ancestor;
+
+	cgrp = bpf_cgroup_from_id(cgrp_id);
+	if (!cgrp)
+		return 0;
+
+	ancestor = bpf_cgroup_ancestor(cgrp, 1);
+	if (!ancestor)
+		goto out;
+
+	read_xattr(cgrp);
+	bpf_cgroup_release(ancestor);
+out:
+	bpf_cgroup_release(cgrp);
+	return 0;
+}