451 lines
14 KiB
C
451 lines
14 KiB
C
|
// SPDX-License-Identifier: GPL-2.0
|
||
|
/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
|
||
|
|
||
|
#include <test_progs.h>
|
||
|
#include <bpf/btf.h>
|
||
|
|
||
|
#include "test_log_buf.skel.h"
|
||
|
|
||
|
|
||
|
static bool check_prog_load(int prog_fd, bool expect_err, const char *tag)
|
||
|
{
|
||
|
if (expect_err) {
|
||
|
if (!ASSERT_LT(prog_fd, 0, tag)) {
|
||
|
close(prog_fd);
|
||
|
return false;
|
||
|
}
|
||
|
} else /* !expect_err */ {
|
||
|
if (!ASSERT_GT(prog_fd, 0, tag))
|
||
|
return false;
|
||
|
}
|
||
|
if (prog_fd >= 0)
|
||
|
close(prog_fd);
|
||
|
return true;
|
||
|
}
|
||
|
|
||
|
static struct {
|
||
|
/* strategically placed before others to avoid accidental modification by kernel */
|
||
|
char filler[1024];
|
||
|
char buf[1024];
|
||
|
/* strategically placed after buf[] to catch more accidental corruptions */
|
||
|
char reference[1024];
|
||
|
} logs;
|
||
|
static const struct bpf_insn *insns;
|
||
|
static size_t insn_cnt;
|
||
|
|
||
|
static int load_prog(struct bpf_prog_load_opts *opts, bool expect_load_error)
|
||
|
{
|
||
|
int prog_fd;
|
||
|
|
||
|
prog_fd = bpf_prog_load(BPF_PROG_TYPE_RAW_TRACEPOINT, "log_prog",
|
||
|
"GPL", insns, insn_cnt, opts);
|
||
|
check_prog_load(prog_fd, expect_load_error, "prog_load");
|
||
|
|
||
|
return prog_fd;
|
||
|
}
|
||
|
|
||
|
static void verif_log_subtest(const char *name, bool expect_load_error, int log_level)
|
||
|
{
|
||
|
LIBBPF_OPTS(bpf_prog_load_opts, opts);
|
||
|
char *exp_log, prog_name[16], op_name[32];
|
||
|
struct test_log_buf *skel;
|
||
|
struct bpf_program *prog;
|
||
|
size_t fixed_log_sz;
|
||
|
__u32 log_true_sz_fixed, log_true_sz_rolling;
|
||
|
int i, mode, err, prog_fd, res;
|
||
|
|
||
|
skel = test_log_buf__open();
|
||
|
if (!ASSERT_OK_PTR(skel, "skel_open"))
|
||
|
return;
|
||
|
|
||
|
bpf_object__for_each_program(prog, skel->obj) {
|
||
|
if (strcmp(bpf_program__name(prog), name) == 0)
|
||
|
bpf_program__set_autoload(prog, true);
|
||
|
else
|
||
|
bpf_program__set_autoload(prog, false);
|
||
|
}
|
||
|
|
||
|
err = test_log_buf__load(skel);
|
||
|
if (!expect_load_error && !ASSERT_OK(err, "unexpected_load_failure"))
|
||
|
goto cleanup;
|
||
|
if (expect_load_error && !ASSERT_ERR(err, "unexpected_load_success"))
|
||
|
goto cleanup;
|
||
|
|
||
|
insns = bpf_program__insns(skel->progs.good_prog);
|
||
|
insn_cnt = bpf_program__insn_cnt(skel->progs.good_prog);
|
||
|
|
||
|
opts.log_buf = logs.reference;
|
||
|
opts.log_size = sizeof(logs.reference);
|
||
|
opts.log_level = log_level | 8 /* BPF_LOG_FIXED */;
|
||
|
load_prog(&opts, expect_load_error);
|
||
|
|
||
|
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 works as verifier log used to work, that is:
|
||
|
* we get -ENOSPC and beginning of the full verifier log. This only
|
||
|
* works for log_level 2 and log_level 1 + failed program. For log
|
||
|
* level 2 we don't reset log at all. For log_level 1 + failed program
|
||
|
* we don't get to verification stats output. With log level 1
|
||
|
* for successful program final result will be just verifier stats.
|
||
|
* But if provided too short log buf, kernel will NULL-out log->ubuf
|
||
|
* and will stop emitting further log. This means we'll never see
|
||
|
* predictable verifier stats.
|
||
|
* Long story short, we do the following -ENOSPC test only for
|
||
|
* predictable combinations.
|
||
|
*/
|
||
|
if (log_level >= 2 || expect_load_error) {
|
||
|
opts.log_buf = logs.buf;
|
||
|
opts.log_level = log_level | 8; /* fixed-length log */
|
||
|
opts.log_size = 25;
|
||
|
|
||
|
prog_fd = bpf_prog_load(BPF_PROG_TYPE_RAW_TRACEPOINT, "log_fixed25",
|
||
|
"GPL", insns, insn_cnt, &opts);
|
||
|
if (!ASSERT_EQ(prog_fd, -ENOSPC, "unexpected_log_fixed_prog_load_result")) {
|
||
|
if (prog_fd >= 0)
|
||
|
close(prog_fd);
|
||
|
goto cleanup;
|
||
|
}
|
||
|
if (!ASSERT_EQ(strlen(logs.buf), 24, "log_fixed_25"))
|
||
|
goto cleanup;
|
||
|
if (!ASSERT_STRNEQ(logs.buf, logs.reference, 24, "log_fixed_contents_25"))
|
||
|
goto cleanup;
|
||
|
}
|
||
|
|
||
|
/* validate rolling verifier log logic: try all variations of log buf
|
||
|
* length to force various truncation scenarios
|
||
|
*/
|
||
|
opts.log_buf = logs.buf;
|
||
|
|
||
|
/* rotating mode, then fixed mode */
|
||
|
for (mode = 1; mode >= 0; mode--) {
|
||
|
/* 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;
|
||
|
opts.log_level = log_level | (mode ? 0 : 8 /* BPF_LOG_FIXED */);
|
||
|
|
||
|
snprintf(prog_name, sizeof(prog_name),
|
||
|
"log_%s_%d", mode ? "roll" : "fixed", i);
|
||
|
prog_fd = bpf_prog_load(BPF_PROG_TYPE_RAW_TRACEPOINT, prog_name,
|
||
|
"GPL", insns, insn_cnt, &opts);
|
||
|
|
||
|
snprintf(op_name, sizeof(op_name),
|
||
|
"log_%s_prog_load_%d", mode ? "roll" : "fixed", i);
|
||
|
if (!ASSERT_EQ(prog_fd, -ENOSPC, op_name)) {
|
||
|
if (prog_fd >= 0)
|
||
|
close(prog_fd);
|
||
|
goto cleanup;
|
||
|
}
|
||
|
|
||
|
snprintf(op_name, sizeof(op_name),
|
||
|
"log_%s_strlen_%d", mode ? "roll" : "fixed", i);
|
||
|
ASSERT_EQ(strlen(logs.buf), i - 1, op_name);
|
||
|
|
||
|
if (mode)
|
||
|
exp_log = logs.reference + fixed_log_sz - i;
|
||
|
else
|
||
|
exp_log = logs.reference;
|
||
|
|
||
|
snprintf(op_name, sizeof(op_name),
|
||
|
"log_%s_contents_%d", mode ? "roll" : "fixed", i);
|
||
|
if (!ASSERT_STRNEQ(logs.buf, exp_log, i - 1, op_name)) {
|
||
|
printf("CMP:%d\nS1:'%s'\nS2:'%s'\n",
|
||
|
strncmp(logs.buf, exp_log, i - 1),
|
||
|
logs.buf, exp_log);
|
||
|
goto cleanup;
|
||
|
}
|
||
|
|
||
|
/* check that unused portions of logs.buf is not overwritten */
|
||
|
snprintf(op_name, sizeof(op_name),
|
||
|
"log_%s_unused_%d", mode ? "roll" : "fixed", 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 = log_level | 8; /* BPF_LOG_FIXED */
|
||
|
opts.log_size = sizeof(logs.buf);
|
||
|
opts.log_true_size = 0;
|
||
|
res = load_prog(&opts, expect_load_error);
|
||
|
ASSERT_NEQ(res, -ENOSPC, "prog_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 = log_level | 8; /* BPF_LOG_FIXED */
|
||
|
opts.log_size = 0;
|
||
|
opts.log_true_size = 0;
|
||
|
res = load_prog(&opts, expect_load_error);
|
||
|
ASSERT_NEQ(res, -ENOSPC, "prog_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 = log_level;
|
||
|
opts.log_size = sizeof(logs.buf);
|
||
|
opts.log_true_size = 0;
|
||
|
res = load_prog(&opts, expect_load_error);
|
||
|
ASSERT_NEQ(res, -ENOSPC, "prog_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 = log_level;
|
||
|
opts.log_size = 0;
|
||
|
opts.log_true_size = 0;
|
||
|
res = load_prog(&opts, expect_load_error);
|
||
|
ASSERT_NEQ(res, -ENOSPC, "prog_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 = log_level | 8; /* BPF_LOG_FIXED */
|
||
|
opts.log_size = log_true_sz_fixed - 1;
|
||
|
opts.log_true_size = 0;
|
||
|
res = load_prog(&opts, true /* should fail */);
|
||
|
ASSERT_EQ(res, -ENOSPC, "prog_load_res_too_short_fixed");
|
||
|
|
||
|
/* (FIXED) expect *not* -ENOSPC with exact log_true_size buffer */
|
||
|
opts.log_buf = logs.buf;
|
||
|
opts.log_level = log_level | 8; /* BPF_LOG_FIXED */
|
||
|
opts.log_size = log_true_sz_fixed;
|
||
|
opts.log_true_size = 0;
|
||
|
res = load_prog(&opts, expect_load_error);
|
||
|
ASSERT_NEQ(res, -ENOSPC, "prog_load_res_just_right_fixed");
|
||
|
|
||
|
/* (ROLLING) expect -ENOSPC for one byte short log */
|
||
|
opts.log_buf = logs.buf;
|
||
|
opts.log_level = log_level;
|
||
|
opts.log_size = log_true_sz_rolling - 1;
|
||
|
res = load_prog(&opts, true /* should fail */);
|
||
|
ASSERT_EQ(res, -ENOSPC, "prog_load_res_too_short_rolling");
|
||
|
|
||
|
/* (ROLLING) expect *not* -ENOSPC with exact log_true_size buffer */
|
||
|
opts.log_buf = logs.buf;
|
||
|
opts.log_level = log_level;
|
||
|
opts.log_size = log_true_sz_rolling;
|
||
|
opts.log_true_size = 0;
|
||
|
res = load_prog(&opts, expect_load_error);
|
||
|
ASSERT_NEQ(res, -ENOSPC, "prog_load_res_just_right_rolling");
|
||
|
|
||
|
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"))
|
||
|
verif_log_subtest("good_prog", false, 1);
|
||
|
if (test__start_subtest("good_prog-level2"))
|
||
|
verif_log_subtest("good_prog", false, 2);
|
||
|
if (test__start_subtest("bad_prog-level1"))
|
||
|
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 */);
|
||
|
}
|