From 838bd4ac9aa35bdf43bf0199fa8eef9d3a004611 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 2 Mar 2023 20:14:44 -0800 Subject: selftests/bpf: Add a test case for kptr_rcu. Tweak existing map_kptr test to check kptr_rcu. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: David Vernet Link: https://lore.kernel.org/bpf/20230303041446.3630-5-alexei.starovoitov@gmail.com --- tools/testing/selftests/bpf/progs/map_kptr.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'tools') diff --git a/tools/testing/selftests/bpf/progs/map_kptr.c b/tools/testing/selftests/bpf/progs/map_kptr.c index 3fe7cde4cbfd..3903d30217b8 100644 --- a/tools/testing/selftests/bpf/progs/map_kptr.c +++ b/tools/testing/selftests/bpf/progs/map_kptr.c @@ -118,6 +118,7 @@ extern struct prog_test_ref_kfunc *bpf_kfunc_call_test_acquire(unsigned long *sp extern struct prog_test_ref_kfunc * bpf_kfunc_call_test_kptr_get(struct prog_test_ref_kfunc **p, int a, int b) __ksym; extern void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym; +void bpf_kfunc_call_test_ref(struct prog_test_ref_kfunc *p) __ksym; #define WRITE_ONCE(x, val) ((*(volatile typeof(x) *) &(x)) = (val)) @@ -147,12 +148,23 @@ static void test_kptr_ref(struct map_value *v) WRITE_ONCE(v->unref_ptr, p); if (!p) return; + /* + * p is rcu_ptr_prog_test_ref_kfunc, + * because bpf prog is non-sleepable and runs in RCU CS. + * p can be passed to kfunc that requires KF_RCU. + */ + bpf_kfunc_call_test_ref(p); if (p->a + p->b > 100) return; /* store NULL */ p = bpf_kptr_xchg(&v->ref_ptr, NULL); if (!p) return; + /* + * p is trusted_ptr_prog_test_ref_kfunc. + * p can be passed to kfunc that requires KF_RCU. + */ + bpf_kfunc_call_test_ref(p); if (p->a + p->b > 100) { bpf_kfunc_call_test_release(p); return; -- cgit v1.2.3