From: Alexei Starovoitov <ast@xxxxxxxxxx>
Adjust cgroup kfunc test to dereference RCU protected cgroup pointer
as PTR_TRUSTED and pass into KF_TRUSTED_ARGS kfunc.
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
.../testing/selftests/bpf/progs/cgrp_kfunc_success.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c b/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c
index 42e13aebdd62..030aff700084 100644
--- a/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c
+++ b/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c
@@ -61,7 +61,7 @@ int BPF_PROG(test_cgrp_acquire_leave_in_map, struct cgroup *cgrp, const char *pa
SEC("tp_btf/cgroup_mkdir")
int BPF_PROG(test_cgrp_xchg_release, struct cgroup *cgrp, const char *path)
{
- struct cgroup *kptr;
+ struct cgroup *kptr, *cg;
struct __cgrps_kfunc_map_value *v;
long status;
@@ -80,6 +80,16 @@ int BPF_PROG(test_cgrp_xchg_release, struct cgroup *cgrp, const char *path)
return 0;
}
+ kptr = v->cgrp;
+ if (!kptr) {
+ err = 4;
+ return 0;
+ }
+
+ cg = bpf_cgroup_ancestor(kptr, 1);
+ if (cg) /* verifier only check */
+ bpf_cgroup_release(cg);
+
kptr = bpf_kptr_xchg(&v->cgrp, NULL);
if (!kptr) {
err = 3;
--
2.39.2
