Commit f460e7bd authored by Dave Marchevsky's avatar Dave Marchevsky Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add test passing MAYBE_NULL reg to bpf_refcount_acquire 



The test added in this patch exercises the logic fixed in the previous
patch in this series. Before the previous patch's changes,
bpf_refcount_acquire accepts MAYBE_NULL local kptrs; after the change
the verifier correctly rejects the such a call.

Signed-off-by: default avatarDave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20231107085639.3016113-3-davemarchevsky@fb.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 1500a5d9

tools/testing/selftests/bpf/progs/refcounted_kptr_fail.c

+19 −0
Original line number Diff line number Diff line
@@ -53,6 +53,25 @@ long rbtree_refcounted_node_ref_escapes(void *ctx) 
	return 0;

}



SEC("?tc")

__failure __msg("Possibly NULL pointer passed to trusted arg0")

long refcount_acquire_maybe_null(void *ctx)

{

	struct node_acquire *n, *m;



	n = bpf_obj_new(typeof(*n));

	/* Intentionally not testing !n

	 * it's MAYBE_NULL for refcount_acquire

	 */

	m = bpf_refcount_acquire(n);

	if (m)

		bpf_obj_drop(m);

	if (n)

		bpf_obj_drop(n);



	return 0;

}



SEC("?tc")

__failure __msg("Unreleased reference id=3 alloc_insn=9")

long rbtree_refcounted_node_ref_escapes_owning_input(void *ctx)