This adds test to enforce same check for the return code for the extended prog as it is enforced for the target program. It asserts failure for a return code, which is permitted without the patch in this series, while it is restricted after the application of this patch. Signed-off-by: Udip Pant <udippant@xxxxxx> --- .../selftests/bpf/prog_tests/fexit_bpf2bpf.c | 40 +++++++++++++++++++ .../bpf/progs/freplace_connect_v4_prog.c | 19 +++++++++ 2 files changed, 59 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/freplace_connect_v4_prog.c diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c index 7c7168963d52..d295ca9bbf96 100644 --- a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c +++ b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c @@ -142,10 +142,50 @@ static void test_func_replace_verify(void) prog_name, false); } +static void test_func_replace_return_code(void) +{ + /* + * standalone test that asserts failure to load freplace prog + * because of invalid return code. + */ + struct bpf_object *obj = NULL, *pkt_obj; + int err, pkt_fd; + __u32 duration = 0; + const char *target_obj_file = "./connect4_prog.o"; + const char *obj_file = "./freplace_connect_v4_prog.o"; + + err = bpf_prog_load(target_obj_file, BPF_PROG_TYPE_UNSPEC, + &pkt_obj, &pkt_fd); + /* the target prog should load fine */ + if (CHECK(err, "tgt_prog_load", "file %s err %d errno %d\n", + target_obj_file, err, errno)) + return; + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts, + .attach_prog_fd = pkt_fd, + ); + + obj = bpf_object__open_file(obj_file, &opts); + if (CHECK(IS_ERR_OR_NULL(obj), "obj_open", + "failed to open %s: %ld\n", obj_file, + PTR_ERR(obj))) + goto close_prog; + + /* It should fail to load the program */ + err = bpf_object__load(obj); + if (CHECK(!err, "bpf_obj_load should fail", "err %d\n", err)) + goto close_prog; + +close_prog: + if (!IS_ERR_OR_NULL(obj)) + bpf_object__close(obj); + bpf_object__close(pkt_obj); +} + void test_fexit_bpf2bpf(void) { test_target_no_callees(); test_target_yes_callees(); test_func_replace(); test_func_replace_verify(); + test_func_replace_return_code(); } diff --git a/tools/testing/selftests/bpf/progs/freplace_connect_v4_prog.c b/tools/testing/selftests/bpf/progs/freplace_connect_v4_prog.c new file mode 100644 index 000000000000..544e5ac90461 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/freplace_connect_v4_prog.c @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2020 Facebook + +#include <linux/stddef.h> +#include <linux/ipv6.h> +#include <linux/bpf.h> +#include <linux/in.h> +#include <sys/socket.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_endian.h> + +SEC("freplace/connect_v4_prog") +int new_connect_v4_prog(struct bpf_sock_addr *ctx) +{ + // return value thats in invalid range + return 255; +} + +char _license[] SEC("license") = "GPL"; -- 2.24.1