bpf: Fix tests for local_storage

The {inode,sk}_storage_result checking if the correct value was retrieved
was being clobbered unconditionally by the return value of the
bpf_{inode,sk}_storage_delete call.

Also, consistently use the newly added BPF_LOCAL_STORAGE_GET_F_CREATE
flag.

Fixes: cd324d7a ("bpf: Add selftests for local_storage")
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-7-kpsingh@chromium.org

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

@@ -58,20 +58,22 @@ int BPF_PROG(unlink_hook, struct inode *dir, struct dentry *victim)
 {
 	__u32 pid = bpf_get_current_pid_tgid() >> 32;
 	struct dummy_storage *storage;
+	int err;
 
 	if (pid != monitored_pid)
 		return 0;
 
 	storage = bpf_inode_storage_get(&inode_storage_map, victim->d_inode, 0,
-				     BPF_SK_STORAGE_GET_F_CREATE);
+					BPF_LOCAL_STORAGE_GET_F_CREATE);
 	if (!storage)
 		return 0;
 
-	if (storage->value == DUMMY_STORAGE_VALUE)
+	if (storage->value != DUMMY_STORAGE_VALUE)
 		inode_storage_result = -1;
 
-	inode_storage_result =
-		bpf_inode_storage_delete(&inode_storage_map, victim->d_inode);
+	err = bpf_inode_storage_delete(&inode_storage_map, victim->d_inode);
+	if (!err)
+		inode_storage_result = err;
 
 	return 0;
 }
@@ -82,19 +84,23 @@ int BPF_PROG(socket_bind, struct socket *sock, struct sockaddr *address,
 {
 	__u32 pid = bpf_get_current_pid_tgid() >> 32;
 	struct dummy_storage *storage;
+	int err;
 
 	if (pid != monitored_pid)
 		return 0;
 
 	storage = bpf_sk_storage_get(&sk_storage_map, sock->sk, 0,
-				     BPF_SK_STORAGE_GET_F_CREATE);
+				     BPF_LOCAL_STORAGE_GET_F_CREATE);
 	if (!storage)
 		return 0;
 
-	if (storage->value == DUMMY_STORAGE_VALUE)
+	if (storage->value != DUMMY_STORAGE_VALUE)
 		sk_storage_result = -1;
 
-	sk_storage_result = bpf_sk_storage_delete(&sk_storage_map, sock->sk);
+	err = bpf_sk_storage_delete(&sk_storage_map, sock->sk);
+	if (!err)
+		sk_storage_result = err;
+
 	return 0;
 }
 
@@ -109,7 +115,7 @@ int BPF_PROG(socket_post_create, struct socket *sock, int family, int type,
 		return 0;
 
 	storage = bpf_sk_storage_get(&sk_storage_map, sock->sk, 0,
-				     BPF_SK_STORAGE_GET_F_CREATE);
+				     BPF_LOCAL_STORAGE_GET_F_CREATE);
 	if (!storage)
 		return 0;