selftests/bpf: Add verifier log tests for BPF_BTF_LOAD command
Add verifier log tests for BPF_BTF_LOAD command, which are very similar, conceptually, to BPF_PROG_LOAD tests. These are two separate commands dealing with verbose verifier log, so should be both tested separately. Test that log_buf==NULL condition *does not* return -ENOSPC. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Lorenz Bauer <lmb@isovalent.com> Link: https://lore.kernel.org/bpf/20230406234205.323208-20-andrii@kernel.org
This commit is contained in:
Andrii Nakryiko
Daniel Borkmann
parent
be983f4427
commit
054b6c7866
@ -249,6 +249,190 @@ cleanup:
|
||||
test_log_buf__destroy(skel);
|
||||
}
|
||||
|
||||
static const void *btf_data;
|
||||
static u32 btf_data_sz;
|
||||
|
||||
static int load_btf(struct bpf_btf_load_opts *opts, bool expect_err)
|
||||
{
|
||||
int fd;
|
||||
|
||||
fd = bpf_btf_load(btf_data, btf_data_sz, opts);
|
||||
if (fd >= 0)
|
||||
close(fd);
|
||||
if (expect_err)
|
||||
ASSERT_LT(fd, 0, "btf_load_failure");
|
||||
else /* !expect_err */
|
||||
ASSERT_GT(fd, 0, "btf_load_success");
|
||||
return fd;
|
||||
}
|
||||
|
||||
static void verif_btf_log_subtest(bool bad_btf)
|
||||
{
|
||||
LIBBPF_OPTS(bpf_btf_load_opts, opts);
|
||||
struct btf *btf;
|
||||
struct btf_type *t;
|
||||
char *exp_log, op_name[32];
|
||||
size_t fixed_log_sz;
|
||||
__u32 log_true_sz_fixed, log_true_sz_rolling;
|
||||
int i, res;
|
||||
|
||||
/* prepare simple BTF contents */
|
||||
btf = btf__new_empty();
|
||||
if (!ASSERT_OK_PTR(btf, "btf_new_empty"))
|
||||
return;
|
||||
res = btf__add_int(btf, "whatever", 4, 0);
|
||||
if (!ASSERT_GT(res, 0, "btf_add_int_id"))
|
||||
goto cleanup;
|
||||
if (bad_btf) {
|
||||
/* btf__add_int() doesn't allow bad value of size, so we'll just
|
||||
* force-cast btf_type pointer and manually override size to invalid
|
||||
* 3 if we need to simulate failure
|
||||
*/
|
||||
t = (void *)btf__type_by_id(btf, res);
|
||||
if (!ASSERT_OK_PTR(t, "int_btf_type"))
|
||||
goto cleanup;
|
||||
t->size = 3;
|
||||
}
|
||||
|
||||
btf_data = btf__raw_data(btf, &btf_data_sz);
|
||||
if (!ASSERT_OK_PTR(btf_data, "btf_data"))
|
||||
goto cleanup;
|
||||
|
||||
load_btf(&opts, bad_btf);
|
||||
|
||||
opts.log_buf = logs.reference;
|
||||
opts.log_size = sizeof(logs.reference);
|
||||
opts.log_level = 1 | 8 /* BPF_LOG_FIXED */;
|
||||
load_btf(&opts, bad_btf);
|
||||
|
||||
fixed_log_sz = strlen(logs.reference) + 1;
|
||||
if (!ASSERT_GT(fixed_log_sz, 50, "fixed_log_sz"))
|
||||
goto cleanup;
|
||||
memset(logs.reference + fixed_log_sz, 0, sizeof(logs.reference) - fixed_log_sz);
|
||||
|
||||
/* validate BPF_LOG_FIXED truncation works as verifier log used to work */
|
||||
opts.log_buf = logs.buf;
|
||||
opts.log_level = 1 | 8; /* fixed-length log */
|
||||
opts.log_size = 25;
|
||||
res = load_btf(&opts, true);
|
||||
ASSERT_EQ(res, -ENOSPC, "half_log_fd");
|
||||
ASSERT_EQ(strlen(logs.buf), 24, "log_fixed_25");
|
||||
ASSERT_STRNEQ(logs.buf, logs.reference, 24, op_name);
|
||||
|
||||
/* validate rolling verifier log logic: try all variations of log buf
|
||||
* length to force various truncation scenarios
|
||||
*/
|
||||
opts.log_buf = logs.buf;
|
||||
opts.log_level = 1; /* rolling log */
|
||||
|
||||
/* prefill logs.buf with 'A's to detect any write beyond allowed length */
|
||||
memset(logs.filler, 'A', sizeof(logs.filler));
|
||||
logs.filler[sizeof(logs.filler) - 1] = '\0';
|
||||
memset(logs.buf, 'A', sizeof(logs.buf));
|
||||
logs.buf[sizeof(logs.buf) - 1] = '\0';
|
||||
|
||||
for (i = 1; i < fixed_log_sz; i++) {
|
||||
opts.log_size = i;
|
||||
|
||||
snprintf(op_name, sizeof(op_name), "log_roll_btf_load_%d", i);
|
||||
res = load_btf(&opts, true);
|
||||
if (!ASSERT_EQ(res, -ENOSPC, op_name))
|
||||
goto cleanup;
|
||||
|
||||
exp_log = logs.reference + fixed_log_sz - i;
|
||||
snprintf(op_name, sizeof(op_name), "log_roll_contents_%d", i);
|
||||
if (!ASSERT_STREQ(logs.buf, exp_log, op_name)) {
|
||||
printf("CMP:%d\nS1:'%s'\nS2:'%s'\n",
|
||||
strcmp(logs.buf, exp_log),
|
||||
logs.buf, exp_log);
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
/* check that unused portions of logs.buf are not overwritten */
|
||||
snprintf(op_name, sizeof(op_name), "log_roll_unused_tail_%d", i);
|
||||
if (!ASSERT_STREQ(logs.buf + i, logs.filler + i, op_name)) {
|
||||
printf("CMP:%d\nS1:'%s'\nS2:'%s'\n",
|
||||
strcmp(logs.buf + i, logs.filler + i),
|
||||
logs.buf + i, logs.filler + i);
|
||||
goto cleanup;
|
||||
}
|
||||
}
|
||||
|
||||
/* (FIXED) get actual log size */
|
||||
opts.log_buf = logs.buf;
|
||||
opts.log_level = 1 | 8; /* BPF_LOG_FIXED */
|
||||
opts.log_size = sizeof(logs.buf);
|
||||
opts.log_true_size = 0;
|
||||
res = load_btf(&opts, bad_btf);
|
||||
ASSERT_NEQ(res, -ENOSPC, "btf_load_res_fixed");
|
||||
|
||||
log_true_sz_fixed = opts.log_true_size;
|
||||
ASSERT_GT(log_true_sz_fixed, 0, "log_true_sz_fixed");
|
||||
|
||||
/* (FIXED, NULL) get actual log size */
|
||||
opts.log_buf = NULL;
|
||||
opts.log_level = 1 | 8; /* BPF_LOG_FIXED */
|
||||
opts.log_size = 0;
|
||||
opts.log_true_size = 0;
|
||||
res = load_btf(&opts, bad_btf);
|
||||
ASSERT_NEQ(res, -ENOSPC, "btf_load_res_fixed_null");
|
||||
ASSERT_EQ(opts.log_true_size, log_true_sz_fixed, "log_sz_fixed_null_eq");
|
||||
|
||||
/* (ROLLING) get actual log size */
|
||||
opts.log_buf = logs.buf;
|
||||
opts.log_level = 1;
|
||||
opts.log_size = sizeof(logs.buf);
|
||||
opts.log_true_size = 0;
|
||||
res = load_btf(&opts, bad_btf);
|
||||
ASSERT_NEQ(res, -ENOSPC, "btf_load_res_rolling");
|
||||
|
||||
log_true_sz_rolling = opts.log_true_size;
|
||||
ASSERT_EQ(log_true_sz_rolling, log_true_sz_fixed, "log_true_sz_eq");
|
||||
|
||||
/* (ROLLING, NULL) get actual log size */
|
||||
opts.log_buf = NULL;
|
||||
opts.log_level = 1;
|
||||
opts.log_size = 0;
|
||||
opts.log_true_size = 0;
|
||||
res = load_btf(&opts, bad_btf);
|
||||
ASSERT_NEQ(res, -ENOSPC, "btf_load_res_rolling_null");
|
||||
ASSERT_EQ(opts.log_true_size, log_true_sz_rolling, "log_true_sz_null_eq");
|
||||
|
||||
/* (FIXED) expect -ENOSPC for one byte short log */
|
||||
opts.log_buf = logs.buf;
|
||||
opts.log_level = 1 | 8; /* BPF_LOG_FIXED */
|
||||
opts.log_size = log_true_sz_fixed - 1;
|
||||
opts.log_true_size = 0;
|
||||
res = load_btf(&opts, true);
|
||||
ASSERT_EQ(res, -ENOSPC, "btf_load_res_too_short_fixed");
|
||||
|
||||
/* (FIXED) expect *not* -ENOSPC with exact log_true_size buffer */
|
||||
opts.log_buf = logs.buf;
|
||||
opts.log_level = 1 | 8; /* BPF_LOG_FIXED */
|
||||
opts.log_size = log_true_sz_fixed;
|
||||
opts.log_true_size = 0;
|
||||
res = load_btf(&opts, bad_btf);
|
||||
ASSERT_NEQ(res, -ENOSPC, "btf_load_res_just_right_fixed");
|
||||
|
||||
/* (ROLLING) expect -ENOSPC for one byte short log */
|
||||
opts.log_buf = logs.buf;
|
||||
opts.log_level = 1;
|
||||
opts.log_size = log_true_sz_rolling - 1;
|
||||
res = load_btf(&opts, true);
|
||||
ASSERT_EQ(res, -ENOSPC, "btf_load_res_too_short_rolling");
|
||||
|
||||
/* (ROLLING) expect *not* -ENOSPC with exact log_true_size buffer */
|
||||
opts.log_buf = logs.buf;
|
||||
opts.log_level = 1;
|
||||
opts.log_size = log_true_sz_rolling;
|
||||
opts.log_true_size = 0;
|
||||
res = load_btf(&opts, bad_btf);
|
||||
ASSERT_NEQ(res, -ENOSPC, "btf_load_res_just_right_rolling");
|
||||
|
||||
cleanup:
|
||||
btf__free(btf);
|
||||
}
|
||||
|
||||
void test_verifier_log(void)
|
||||
{
|
||||
if (test__start_subtest("good_prog-level1"))
|
||||
@ -259,4 +443,8 @@ void test_verifier_log(void)
|
||||
verif_log_subtest("bad_prog", true, 1);
|
||||
if (test__start_subtest("bad_prog-level2"))
|
||||
verif_log_subtest("bad_prog", true, 2);
|
||||
if (test__start_subtest("bad_btf"))
|
||||
verif_btf_log_subtest(true /* bad btf */);
|
||||
if (test__start_subtest("good_btf"))
|
||||
verif_btf_log_subtest(false /* !bad btf */);
|
||||
}
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user