linux-stable/tools/testing/selftests/bpf/test_loader.c

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selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */
#include <linux/capability.h>
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
#include <stdlib.h>
#include <test_progs.h>
#include <bpf/btf.h>
#include "autoconf_helper.h"
#include "unpriv_helpers.h"
#include "cap_helpers.h"
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
#define str_has_pfx(str, pfx) \
(strncmp(str, pfx, __builtin_constant_p(pfx) ? sizeof(pfx) - 1 : strlen(pfx)) == 0)
#define TEST_LOADER_LOG_BUF_SZ 2097152
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
#define TEST_TAG_EXPECT_FAILURE "comment:test_expect_failure"
#define TEST_TAG_EXPECT_SUCCESS "comment:test_expect_success"
#define TEST_TAG_EXPECT_MSG_PFX "comment:test_expect_msg="
#define TEST_TAG_EXPECT_FAILURE_UNPRIV "comment:test_expect_failure_unpriv"
#define TEST_TAG_EXPECT_SUCCESS_UNPRIV "comment:test_expect_success_unpriv"
#define TEST_TAG_EXPECT_MSG_PFX_UNPRIV "comment:test_expect_msg_unpriv="
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
#define TEST_TAG_LOG_LEVEL_PFX "comment:test_log_level="
#define TEST_TAG_PROG_FLAGS_PFX "comment:test_prog_flags="
#define TEST_TAG_DESCRIPTION_PFX "comment:test_description="
#define TEST_TAG_RETVAL_PFX "comment:test_retval="
#define TEST_TAG_RETVAL_PFX_UNPRIV "comment:test_retval_unpriv="
#define TEST_TAG_AUXILIARY "comment:test_auxiliary"
#define TEST_TAG_AUXILIARY_UNPRIV "comment:test_auxiliary_unpriv"
#define TEST_BTF_PATH "comment:test_btf_path="
/* Warning: duplicated in bpf_misc.h */
#define POINTER_VALUE 0xcafe4all
#define TEST_DATA_LEN 64
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
#define EFFICIENT_UNALIGNED_ACCESS 1
#else
#define EFFICIENT_UNALIGNED_ACCESS 0
#endif
static int sysctl_unpriv_disabled = -1;
enum mode {
PRIV = 1,
UNPRIV = 2
};
struct test_subspec {
char *name;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
bool expect_failure;
const char **expect_msgs;
size_t expect_msg_cnt;
int retval;
bool execute;
};
struct test_spec {
const char *prog_name;
struct test_subspec priv;
struct test_subspec unpriv;
const char *btf_custom_path;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
int log_level;
int prog_flags;
int mode_mask;
bool auxiliary;
bool valid;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
};
static int tester_init(struct test_loader *tester)
{
if (!tester->log_buf) {
tester->log_buf_sz = TEST_LOADER_LOG_BUF_SZ;
tester->log_buf = calloc(tester->log_buf_sz, 1);
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
if (!ASSERT_OK_PTR(tester->log_buf, "tester_log_buf"))
return -ENOMEM;
}
return 0;
}
void test_loader_fini(struct test_loader *tester)
{
if (!tester)
return;
free(tester->log_buf);
}
static void free_test_spec(struct test_spec *spec)
{
free(spec->priv.name);
free(spec->unpriv.name);
free(spec->priv.expect_msgs);
free(spec->unpriv.expect_msgs);
spec->priv.name = NULL;
spec->unpriv.name = NULL;
spec->priv.expect_msgs = NULL;
spec->unpriv.expect_msgs = NULL;
}
static int push_msg(const char *msg, struct test_subspec *subspec)
{
void *tmp;
tmp = realloc(subspec->expect_msgs, (1 + subspec->expect_msg_cnt) * sizeof(void *));
if (!tmp) {
ASSERT_FAIL("failed to realloc memory for messages\n");
return -ENOMEM;
}
subspec->expect_msgs = tmp;
subspec->expect_msgs[subspec->expect_msg_cnt++] = msg;
return 0;
}
static int parse_int(const char *str, int *val, const char *name)
{
char *end;
long tmp;
errno = 0;
if (str_has_pfx(str, "0x"))
tmp = strtol(str + 2, &end, 16);
else
tmp = strtol(str, &end, 10);
if (errno || end[0] != '\0') {
PRINT_FAIL("failed to parse %s from '%s'\n", name, str);
return -EINVAL;
}
*val = tmp;
return 0;
}
static int parse_retval(const char *str, int *val, const char *name)
{
struct {
char *name;
int val;
} named_values[] = {
{ "INT_MIN" , INT_MIN },
{ "POINTER_VALUE", POINTER_VALUE },
{ "TEST_DATA_LEN", TEST_DATA_LEN },
};
int i;
for (i = 0; i < ARRAY_SIZE(named_values); ++i) {
if (strcmp(str, named_values[i].name) != 0)
continue;
*val = named_values[i].val;
return 0;
}
return parse_int(str, val, name);
}
static void update_flags(int *flags, int flag, bool clear)
{
if (clear)
*flags &= ~flag;
else
*flags |= flag;
}
/* Uses btf_decl_tag attributes to describe the expected test
* behavior, see bpf_misc.h for detailed description of each attribute
* and attribute combinations.
*/
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
static int parse_test_spec(struct test_loader *tester,
struct bpf_object *obj,
struct bpf_program *prog,
struct test_spec *spec)
{
const char *description = NULL;
bool has_unpriv_result = false;
bool has_unpriv_retval = false;
int func_id, i, err = 0;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
struct btf *btf;
memset(spec, 0, sizeof(*spec));
spec->prog_name = bpf_program__name(prog);
spec->prog_flags = testing_prog_flags();
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
btf = bpf_object__btf(obj);
if (!btf) {
ASSERT_FAIL("BPF object has no BTF");
return -EINVAL;
}
func_id = btf__find_by_name_kind(btf, spec->prog_name, BTF_KIND_FUNC);
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
if (func_id < 0) {
ASSERT_FAIL("failed to find FUNC BTF type for '%s'", spec->prog_name);
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
return -EINVAL;
}
for (i = 1; i < btf__type_cnt(btf); i++) {
const char *s, *val, *msg;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
const struct btf_type *t;
bool clear;
int flags;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
t = btf__type_by_id(btf, i);
if (!btf_is_decl_tag(t))
continue;
if (t->type != func_id || btf_decl_tag(t)->component_idx != -1)
continue;
s = btf__str_by_offset(btf, t->name_off);
if (str_has_pfx(s, TEST_TAG_DESCRIPTION_PFX)) {
description = s + sizeof(TEST_TAG_DESCRIPTION_PFX) - 1;
} else if (strcmp(s, TEST_TAG_EXPECT_FAILURE) == 0) {
spec->priv.expect_failure = true;
spec->mode_mask |= PRIV;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
} else if (strcmp(s, TEST_TAG_EXPECT_SUCCESS) == 0) {
spec->priv.expect_failure = false;
spec->mode_mask |= PRIV;
} else if (strcmp(s, TEST_TAG_EXPECT_FAILURE_UNPRIV) == 0) {
spec->unpriv.expect_failure = true;
spec->mode_mask |= UNPRIV;
has_unpriv_result = true;
} else if (strcmp(s, TEST_TAG_EXPECT_SUCCESS_UNPRIV) == 0) {
spec->unpriv.expect_failure = false;
spec->mode_mask |= UNPRIV;
has_unpriv_result = true;
} else if (strcmp(s, TEST_TAG_AUXILIARY) == 0) {
spec->auxiliary = true;
spec->mode_mask |= PRIV;
} else if (strcmp(s, TEST_TAG_AUXILIARY_UNPRIV) == 0) {
spec->auxiliary = true;
spec->mode_mask |= UNPRIV;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
} else if (str_has_pfx(s, TEST_TAG_EXPECT_MSG_PFX)) {
msg = s + sizeof(TEST_TAG_EXPECT_MSG_PFX) - 1;
err = push_msg(msg, &spec->priv);
if (err)
goto cleanup;
spec->mode_mask |= PRIV;
} else if (str_has_pfx(s, TEST_TAG_EXPECT_MSG_PFX_UNPRIV)) {
msg = s + sizeof(TEST_TAG_EXPECT_MSG_PFX_UNPRIV) - 1;
err = push_msg(msg, &spec->unpriv);
if (err)
goto cleanup;
spec->mode_mask |= UNPRIV;
} else if (str_has_pfx(s, TEST_TAG_RETVAL_PFX)) {
val = s + sizeof(TEST_TAG_RETVAL_PFX) - 1;
err = parse_retval(val, &spec->priv.retval, "__retval");
if (err)
goto cleanup;
spec->priv.execute = true;
spec->mode_mask |= PRIV;
} else if (str_has_pfx(s, TEST_TAG_RETVAL_PFX_UNPRIV)) {
val = s + sizeof(TEST_TAG_RETVAL_PFX_UNPRIV) - 1;
err = parse_retval(val, &spec->unpriv.retval, "__retval_unpriv");
if (err)
goto cleanup;
spec->mode_mask |= UNPRIV;
spec->unpriv.execute = true;
has_unpriv_retval = true;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
} else if (str_has_pfx(s, TEST_TAG_LOG_LEVEL_PFX)) {
val = s + sizeof(TEST_TAG_LOG_LEVEL_PFX) - 1;
err = parse_int(val, &spec->log_level, "test log level");
if (err)
goto cleanup;
} else if (str_has_pfx(s, TEST_TAG_PROG_FLAGS_PFX)) {
val = s + sizeof(TEST_TAG_PROG_FLAGS_PFX) - 1;
clear = val[0] == '!';
if (clear)
val++;
if (strcmp(val, "BPF_F_STRICT_ALIGNMENT") == 0) {
update_flags(&spec->prog_flags, BPF_F_STRICT_ALIGNMENT, clear);
} else if (strcmp(val, "BPF_F_ANY_ALIGNMENT") == 0) {
update_flags(&spec->prog_flags, BPF_F_ANY_ALIGNMENT, clear);
} else if (strcmp(val, "BPF_F_TEST_RND_HI32") == 0) {
update_flags(&spec->prog_flags, BPF_F_TEST_RND_HI32, clear);
} else if (strcmp(val, "BPF_F_TEST_STATE_FREQ") == 0) {
update_flags(&spec->prog_flags, BPF_F_TEST_STATE_FREQ, clear);
} else if (strcmp(val, "BPF_F_SLEEPABLE") == 0) {
update_flags(&spec->prog_flags, BPF_F_SLEEPABLE, clear);
} else if (strcmp(val, "BPF_F_XDP_HAS_FRAGS") == 0) {
update_flags(&spec->prog_flags, BPF_F_XDP_HAS_FRAGS, clear);
} else if (strcmp(val, "BPF_F_TEST_REG_INVARIANTS") == 0) {
update_flags(&spec->prog_flags, BPF_F_TEST_REG_INVARIANTS, clear);
} else /* assume numeric value */ {
err = parse_int(val, &flags, "test prog flags");
if (err)
goto cleanup;
update_flags(&spec->prog_flags, flags, clear);
}
} else if (str_has_pfx(s, TEST_BTF_PATH)) {
spec->btf_custom_path = s + sizeof(TEST_BTF_PATH) - 1;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
}
}
if (spec->mode_mask == 0)
spec->mode_mask = PRIV;
if (!description)
description = spec->prog_name;
if (spec->mode_mask & PRIV) {
spec->priv.name = strdup(description);
if (!spec->priv.name) {
PRINT_FAIL("failed to allocate memory for priv.name\n");
err = -ENOMEM;
goto cleanup;
}
}
if (spec->mode_mask & UNPRIV) {
int descr_len = strlen(description);
const char *suffix = " @unpriv";
char *name;
name = malloc(descr_len + strlen(suffix) + 1);
if (!name) {
PRINT_FAIL("failed to allocate memory for unpriv.name\n");
err = -ENOMEM;
goto cleanup;
}
strcpy(name, description);
strcpy(&name[descr_len], suffix);
spec->unpriv.name = name;
}
if (spec->mode_mask & (PRIV | UNPRIV)) {
if (!has_unpriv_result)
spec->unpriv.expect_failure = spec->priv.expect_failure;
if (!has_unpriv_retval) {
spec->unpriv.retval = spec->priv.retval;
spec->unpriv.execute = spec->priv.execute;
}
if (!spec->unpriv.expect_msgs) {
size_t sz = spec->priv.expect_msg_cnt * sizeof(void *);
spec->unpriv.expect_msgs = malloc(sz);
if (!spec->unpriv.expect_msgs) {
PRINT_FAIL("failed to allocate memory for unpriv.expect_msgs\n");
err = -ENOMEM;
goto cleanup;
}
memcpy(spec->unpriv.expect_msgs, spec->priv.expect_msgs, sz);
spec->unpriv.expect_msg_cnt = spec->priv.expect_msg_cnt;
}
}
spec->valid = true;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
return 0;
cleanup:
free_test_spec(spec);
return err;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
}
static void prepare_case(struct test_loader *tester,
struct test_spec *spec,
struct bpf_object *obj,
struct bpf_program *prog)
{
int min_log_level = 0, prog_flags;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
if (env.verbosity > VERBOSE_NONE)
min_log_level = 1;
if (env.verbosity > VERBOSE_VERY)
min_log_level = 2;
bpf_program__set_log_buf(prog, tester->log_buf, tester->log_buf_sz);
/* Make sure we set at least minimal log level, unless test requires
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
* even higher level already. Make sure to preserve independent log
* level 4 (verifier stats), though.
*/
if ((spec->log_level & 3) < min_log_level)
bpf_program__set_log_level(prog, (spec->log_level & 4) | min_log_level);
else
bpf_program__set_log_level(prog, spec->log_level);
prog_flags = bpf_program__flags(prog);
bpf_program__set_flags(prog, prog_flags | spec->prog_flags);
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
tester->log_buf[0] = '\0';
tester->next_match_pos = 0;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
}
static void emit_verifier_log(const char *log_buf, bool force)
{
if (!force && env.verbosity == VERBOSE_NONE)
return;
fprintf(stdout, "VERIFIER LOG:\n=============\n%s=============\n", log_buf);
}
static void validate_case(struct test_loader *tester,
struct test_subspec *subspec,
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
struct bpf_object *obj,
struct bpf_program *prog,
int load_err)
{
int i, j;
for (i = 0; i < subspec->expect_msg_cnt; i++) {
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
char *match;
const char *expect_msg;
expect_msg = subspec->expect_msgs[i];
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
match = strstr(tester->log_buf + tester->next_match_pos, expect_msg);
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
if (!ASSERT_OK_PTR(match, "expect_msg")) {
/* if we are in verbose mode, we've already emitted log */
if (env.verbosity == VERBOSE_NONE)
emit_verifier_log(tester->log_buf, true /*force*/);
for (j = 0; j < i; j++)
fprintf(stderr,
"MATCHED MSG: '%s'\n", subspec->expect_msgs[j]);
fprintf(stderr, "EXPECTED MSG: '%s'\n", expect_msg);
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
return;
}
tester->next_match_pos = match - tester->log_buf + strlen(expect_msg);
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
}
}
struct cap_state {
__u64 old_caps;
bool initialized;
};
static int drop_capabilities(struct cap_state *caps)
{
const __u64 caps_to_drop = (1ULL << CAP_SYS_ADMIN | 1ULL << CAP_NET_ADMIN |
1ULL << CAP_PERFMON | 1ULL << CAP_BPF);
int err;
err = cap_disable_effective(caps_to_drop, &caps->old_caps);
if (err) {
PRINT_FAIL("failed to drop capabilities: %i, %s\n", err, strerror(err));
return err;
}
caps->initialized = true;
return 0;
}
static int restore_capabilities(struct cap_state *caps)
{
int err;
if (!caps->initialized)
return 0;
err = cap_enable_effective(caps->old_caps, NULL);
if (err)
PRINT_FAIL("failed to restore capabilities: %i, %s\n", err, strerror(err));
caps->initialized = false;
return err;
}
static bool can_execute_unpriv(struct test_loader *tester, struct test_spec *spec)
{
if (sysctl_unpriv_disabled < 0)
sysctl_unpriv_disabled = get_unpriv_disabled() ? 1 : 0;
if (sysctl_unpriv_disabled)
return false;
if ((spec->prog_flags & BPF_F_ANY_ALIGNMENT) && !EFFICIENT_UNALIGNED_ACCESS)
return false;
return true;
}
static bool is_unpriv_capable_map(struct bpf_map *map)
{
enum bpf_map_type type;
__u32 flags;
type = bpf_map__type(map);
switch (type) {
case BPF_MAP_TYPE_HASH:
case BPF_MAP_TYPE_PERCPU_HASH:
case BPF_MAP_TYPE_HASH_OF_MAPS:
flags = bpf_map__map_flags(map);
return !(flags & BPF_F_ZERO_SEED);
case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE:
case BPF_MAP_TYPE_ARRAY:
case BPF_MAP_TYPE_RINGBUF:
case BPF_MAP_TYPE_PROG_ARRAY:
case BPF_MAP_TYPE_CGROUP_ARRAY:
case BPF_MAP_TYPE_PERCPU_ARRAY:
case BPF_MAP_TYPE_USER_RINGBUF:
case BPF_MAP_TYPE_ARRAY_OF_MAPS:
case BPF_MAP_TYPE_CGROUP_STORAGE:
case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
return true;
default:
return false;
}
}
static int do_prog_test_run(int fd_prog, int *retval, bool empty_opts)
{
__u8 tmp_out[TEST_DATA_LEN << 2] = {};
__u8 tmp_in[TEST_DATA_LEN] = {};
int err, saved_errno;
LIBBPF_OPTS(bpf_test_run_opts, topts,
.data_in = tmp_in,
.data_size_in = sizeof(tmp_in),
.data_out = tmp_out,
.data_size_out = sizeof(tmp_out),
.repeat = 1,
);
if (empty_opts) {
memset(&topts, 0, sizeof(struct bpf_test_run_opts));
topts.sz = sizeof(struct bpf_test_run_opts);
}
err = bpf_prog_test_run_opts(fd_prog, &topts);
saved_errno = errno;
if (err) {
PRINT_FAIL("FAIL: Unexpected bpf_prog_test_run error: %d (%s) ",
saved_errno, strerror(saved_errno));
return err;
}
ASSERT_OK(0, "bpf_prog_test_run");
*retval = topts.retval;
return 0;
}
static bool should_do_test_run(struct test_spec *spec, struct test_subspec *subspec)
{
if (!subspec->execute)
return false;
if (subspec->expect_failure)
return false;
if ((spec->prog_flags & BPF_F_ANY_ALIGNMENT) && !EFFICIENT_UNALIGNED_ACCESS) {
if (env.verbosity != VERBOSE_NONE)
printf("alignment prevents execution\n");
return false;
}
return true;
}
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
/* this function is forced noinline and has short generic name to look better
* in test_progs output (in case of a failure)
*/
static noinline
void run_subtest(struct test_loader *tester,
struct bpf_object_open_opts *open_opts,
const void *obj_bytes,
size_t obj_byte_cnt,
struct test_spec *specs,
struct test_spec *spec,
bool unpriv)
{
struct test_subspec *subspec = unpriv ? &spec->unpriv : &spec->priv;
struct bpf_program *tprog = NULL, *tprog_iter;
struct test_spec *spec_iter;
struct cap_state caps = {};
struct bpf_object *tobj;
struct bpf_map *map;
int retval, err, i;
bool should_load;
if (!test__start_subtest(subspec->name))
return;
if (unpriv) {
if (!can_execute_unpriv(tester, spec)) {
test__skip();
test__end_subtest();
return;
}
if (drop_capabilities(&caps)) {
test__end_subtest();
return;
}
}
/* Implicitly reset to NULL if next test case doesn't specify */
open_opts->btf_custom_path = spec->btf_custom_path;
tobj = bpf_object__open_mem(obj_bytes, obj_byte_cnt, open_opts);
if (!ASSERT_OK_PTR(tobj, "obj_open_mem")) /* shouldn't happen */
goto subtest_cleanup;
i = 0;
bpf_object__for_each_program(tprog_iter, tobj) {
spec_iter = &specs[i++];
should_load = false;
if (spec_iter->valid) {
if (strcmp(bpf_program__name(tprog_iter), spec->prog_name) == 0) {
tprog = tprog_iter;
should_load = true;
}
if (spec_iter->auxiliary &&
spec_iter->mode_mask & (unpriv ? UNPRIV : PRIV))
should_load = true;
}
bpf_program__set_autoload(tprog_iter, should_load);
}
prepare_case(tester, spec, tobj, tprog);
/* By default bpf_object__load() automatically creates all
* maps declared in the skeleton. Some map types are only
* allowed in priv mode. Disable autoload for such maps in
* unpriv mode.
*/
bpf_object__for_each_map(map, tobj)
bpf_map__set_autocreate(map, !unpriv || is_unpriv_capable_map(map));
err = bpf_object__load(tobj);
if (subspec->expect_failure) {
if (!ASSERT_ERR(err, "unexpected_load_success")) {
emit_verifier_log(tester->log_buf, false /*force*/);
goto tobj_cleanup;
}
} else {
if (!ASSERT_OK(err, "unexpected_load_failure")) {
emit_verifier_log(tester->log_buf, true /*force*/);
goto tobj_cleanup;
}
}
emit_verifier_log(tester->log_buf, false /*force*/);
validate_case(tester, subspec, tobj, tprog, err);
if (should_do_test_run(spec, subspec)) {
/* For some reason test_verifier executes programs
* with all capabilities restored. Do the same here.
*/
selftests/bpf: fix __retval() being always ignored Florian Westphal found a bug in and suggested a fix for test_loader.c processing of __retval tag. Because of this bug the function test_loader.c:do_prog_test_run() never executed and all __retval test tags were ignored. If this bug is fixed a number of test cases from progs/verifier_array_access.c fail with retval not matching the expected value. This test was recently converted to use test_loader.c and inline assembly in [1]. When doing the conversion I missed the important detail of test_verifier.c operation: when it creates fixup_map_array_ro, fixup_map_array_wo and fixup_map_array_small it populates these maps with a dummy record. Disabling the __retval checks for the affected verifier_array_access in this commit to avoid false-postivies in any potential bisects. The issue is addressed in the next patch. I verified that the __retval tags are now respected by changing expected return values for all tests annotated with __retval, and checking that these tests started to fail. [1] https://lore.kernel.org/bpf/20230325025524.144043-1-eddyz87@gmail.com/ Fixes: 19a8e06f5f91 ("selftests/bpf: Tests execution support for test_loader.c") Reported-by: Florian Westphal <fw@strlen.de> Link: https://lore.kernel.org/bpf/f4c4aee644425842ee6aa8edf1da68f0a8260e7c.camel@gmail.com/T/ Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20230420232317.2181776-3-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-20 23:23:15 +00:00
if (restore_capabilities(&caps))
goto tobj_cleanup;
if (tester->pre_execution_cb) {
err = tester->pre_execution_cb(tobj);
if (err) {
PRINT_FAIL("pre_execution_cb failed: %d\n", err);
goto tobj_cleanup;
}
}
do_prog_test_run(bpf_program__fd(tprog), &retval,
bpf_program__type(tprog) == BPF_PROG_TYPE_SYSCALL ? true : false);
if (retval != subspec->retval && subspec->retval != POINTER_VALUE) {
PRINT_FAIL("Unexpected retval: %d != %d\n", retval, subspec->retval);
goto tobj_cleanup;
}
}
tobj_cleanup:
bpf_object__close(tobj);
subtest_cleanup:
test__end_subtest();
restore_capabilities(&caps);
}
static void process_subtest(struct test_loader *tester,
const char *skel_name,
skel_elf_bytes_fn elf_bytes_factory)
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
{
LIBBPF_OPTS(bpf_object_open_opts, open_opts, .object_name = skel_name);
struct test_spec *specs = NULL;
struct bpf_object *obj = NULL;
struct bpf_program *prog;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
const void *obj_bytes;
int err, i, nr_progs;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
size_t obj_byte_cnt;
if (tester_init(tester) < 0)
return; /* failed to initialize tester */
obj_bytes = elf_bytes_factory(&obj_byte_cnt);
obj = bpf_object__open_mem(obj_bytes, obj_byte_cnt, &open_opts);
if (!ASSERT_OK_PTR(obj, "obj_open_mem"))
return;
nr_progs = 0;
bpf_object__for_each_program(prog, obj)
++nr_progs;
specs = calloc(nr_progs, sizeof(struct test_spec));
if (!ASSERT_OK_PTR(specs, "specs_alloc"))
return;
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
i = 0;
bpf_object__for_each_program(prog, obj) {
/* ignore tests for which we can't derive test specification */
err = parse_test_spec(tester, obj, prog, &specs[i++]);
if (err)
PRINT_FAIL("Can't parse test spec for program '%s'\n",
bpf_program__name(prog));
}
i = 0;
bpf_object__for_each_program(prog, obj) {
struct test_spec *spec = &specs[i++];
if (!spec->valid || spec->auxiliary)
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
continue;
if (spec->mode_mask & PRIV)
run_subtest(tester, &open_opts, obj_bytes, obj_byte_cnt,
specs, spec, false);
if (spec->mode_mask & UNPRIV)
run_subtest(tester, &open_opts, obj_bytes, obj_byte_cnt,
specs, spec, true);
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
}
for (i = 0; i < nr_progs; ++i)
free_test_spec(&specs[i]);
free(specs);
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
bpf_object__close(obj);
}
void test_loader__run_subtests(struct test_loader *tester,
const char *skel_name,
skel_elf_bytes_fn elf_bytes_factory)
{
/* see comment in run_subtest() for why we do this function nesting */
process_subtest(tester, skel_name, elf_bytes_factory);
selftests/bpf: add generic BPF program tester-loader It's become a common pattern to have a collection of small BPF programs in one BPF object file, each representing one test case. On user-space side of such tests we maintain a table of program names and expected failure or success, along with optional expected verifier log message. This works, but each set of tests reimplement this mundane code over and over again, which is a waste of time for anyone trying to add a new set of tests. Furthermore, it's quite error prone as it's way too easy to miss some entries in these manually maintained test tables (as evidences by dynptr_fail tests, in which ringbuf_release_uninit_dynptr subtest was accidentally missed; this is fixed in next patch). So this patch implements generic test_loader, which accepts skeleton name and handles the rest of details: opens and loads BPF object file, making sure each program is tested in isolation. Optionally each test case can specify expected BPF verifier log message. In case of failure, tester makes sure to report verifier log, but it also reports verifier log in verbose mode unconditionally. Now, the interesting deviation from existing custom implementations is the use of btf_decl_tag attribute to specify expected-to-fail vs expected-to-succeed markers and, optionally, expected log message directly next to BPF program source code, eliminating the need to manually create and update table of tests. We define few macros wrapping btf_decl_tag with a convention that all values of btf_decl_tag start with "comment:" prefix, and then utilizing a very simple "just_some_text_tag" or "some_key_name=<value>" pattern to define things like expected success/failure, expected verifier message, extra verifier log level (if necessary). This approach is demonstrated by next patch in which two existing sets of failure tests are converted. Tester supports both expected-to-fail and expected-to-succeed programs, though this patch set didn't convert any existing expected-to-succeed programs yet, as existing tests couple BPF program loading with their further execution through attach or test_prog_run. One way to allow testing scenarios like this would be ability to specify custom callback, executed for each successfully loaded BPF program. This is left for follow up patches, after some more analysis of existing test cases. This test_loader is, hopefully, a start of a test_verifier-like runner, but integrated into test_progs infrastructure. It will allow much better "user experience" of defining low-level verification tests that can take advantage of all the libbpf-provided nicety features on BPF side: global variables, declarative maps, etc. All while having a choice of defining it in C or as BPF assembly (through __attribute__((naked)) functions and using embedded asm), depending on what makes most sense in each particular case. This will be explored in follow up patches as well. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20221207201648.2990661-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 20:16:47 +00:00
}