Re: [PATCH bpf-next v5 2/2] selftests/bpf: Test case for lacking CFI stub functions.

[Martin KaFai Lau <martin.lau@linux.dev>]

On 2/21/24 6:11 PM, thinker.li@gmail.com wrote:
> +static struct bpf_test_no_cfi_ops __bpf_test_no_cfi_ops = {
> +	.fn_1 = bpf_test_no_cfi_ops__fn_1,
> +	.fn_2 = bpf_test_no_cfi_ops__fn_2,
> +};
> +
> +static struct bpf_struct_ops bpf_bpf_test_no_cif_ops = {

nit. I shortened this to test_no_cif_ops.

> +	.verifier_ops = &dummy_verifier_ops,
> +	.init = dummy_init,
> +	.init_member = dummy_init_member,
> +	.reg = dummy_reg,
> +	.unreg = dummy_unreg,
> +	.name = "bpf_test_no_cfi_ops",
> +	.owner = THIS_MODULE,
> +};
> +
> +static int bpf_test_no_cfi_init(void)
> +{
> +	int ret;
> +
> +	ret = register_bpf_struct_ops(&bpf_bpf_test_no_cif_ops,
> +				      bpf_test_no_cfi_ops);
> +	if (!ret)
> +		return -EINVAL;
> +
> +	bpf_bpf_test_no_cif_ops.cfi_stubs = &__bpf_test_no_cfi_ops;
> +	ret = register_bpf_struct_ops(&bpf_bpf_test_no_cif_ops,
> +				      bpf_test_no_cfi_ops);
> +	return ret;
> +}
> +
> +static void bpf_test_no_cfi_exit(void)
> +{
> +}
> +
> +module_init(bpf_test_no_cfi_init);
> +module_exit(bpf_test_no_cfi_exit);
> +
> +MODULE_AUTHOR("Kuifeng Lee");
> +MODULE_DESCRIPTION("BPF no cfi_stubs test module");
> +MODULE_LICENSE("Dual BSD/GPL");
> +
> diff --git a/tools/testing/selftests/bpf/prog_tests/test_struct_ops_no_cfi.c b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_no_cfi.c
> new file mode 100644
> index 000000000000..f16d4dcccacf
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_no_cfi.c
> @@ -0,0 +1,38 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
> +#include <test_progs.h>
> +#include <testing_helpers.h>
> +
> +static void load_bpf_test_no_cfi(void)
> +{
> +	int fd;
> +	int err;
> +
> +	fd = open("bpf_test_no_cfi.ko", O_RDONLY);
> +	if (!ASSERT_GT(fd, 0, "open")) {
> +		close(fd);

Removed close(fd) here. Also fixed the above ASSERT_GT test. Applied.

The patchwork has picked up the submitter name as "Thinker Lee". I fixed that up 
this time for the cover letter (the merge commit). Not sure where it came from 
and could be due to the nameless sender "from" in the email.

Please write the full name when sending out patch, e.g. "git send-email 
--from="Kui-Feng Lee <thinker.li@gmail.com>" ..."



> +		return;
> +	}
> +
> +	/* The module will try to register a struct_ops type without
> +	 *  cfi_stubs and with cfi_stubs.
> +	 *
> +	 * The one without cfi_stub should fail. The module will be loaded
> +	 * successfully only if the result of the registration is as
> +	 * expected, or it fails.
> +	 */
> +	err = finit_module(fd, "", 0);
> +	close(fd);
> +	if (!ASSERT_OK(err, "finit_module"))
> +		return;
> +
> +	err = delete_module("bpf_test_no_cfi", 0);
> +	ASSERT_OK(err, "delete_module");
> +}
> +