linuxdebug/tools/testing/selftests/user_events/ftrace_test.c

489 lines
12 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* User Events FTrace Test Program
*
* Copyright (c) 2021 Beau Belgrave <beaub@linux.microsoft.com>
*/
#include <errno.h>
#include <linux/user_events.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <unistd.h>
#include "../kselftest_harness.h"
const char *data_file = "/sys/kernel/debug/tracing/user_events_data";
const char *status_file = "/sys/kernel/debug/tracing/user_events_status";
const char *enable_file = "/sys/kernel/debug/tracing/events/user_events/__test_event/enable";
const char *trace_file = "/sys/kernel/debug/tracing/trace";
const char *fmt_file = "/sys/kernel/debug/tracing/events/user_events/__test_event/format";
static inline int status_check(char *status_page, int status_bit)
{
return status_page[status_bit >> 3] & (1 << (status_bit & 7));
}
static int trace_bytes(void)
{
int fd = open(trace_file, O_RDONLY);
char buf[256];
int bytes = 0, got;
if (fd == -1)
return -1;
while (true) {
got = read(fd, buf, sizeof(buf));
if (got == -1)
return -1;
if (got == 0)
break;
bytes += got;
}
close(fd);
return bytes;
}
static int skip_until_empty_line(FILE *fp)
{
int c, last = 0;
while (true) {
c = getc(fp);
if (c == EOF)
break;
if (last == '\n' && c == '\n')
return 0;
last = c;
}
return -1;
}
static int get_print_fmt(char *buffer, int len)
{
FILE *fp = fopen(fmt_file, "r");
char *newline;
if (!fp)
return -1;
/* Read until empty line (Skip Common) */
if (skip_until_empty_line(fp) < 0)
goto err;
/* Read until empty line (Skip Properties) */
if (skip_until_empty_line(fp) < 0)
goto err;
/* Read in print_fmt: */
if (fgets(buffer, len, fp) == NULL)
goto err;
newline = strchr(buffer, '\n');
if (newline)
*newline = '\0';
fclose(fp);
return 0;
err:
fclose(fp);
return -1;
}
static int clear(void)
{
int fd = open(data_file, O_RDWR);
if (fd == -1)
return -1;
if (ioctl(fd, DIAG_IOCSDEL, "__test_event") == -1)
if (errno != ENOENT)
return -1;
close(fd);
return 0;
}
static int check_print_fmt(const char *event, const char *expected)
{
struct user_reg reg = {0};
char print_fmt[256];
int ret;
int fd;
/* Ensure cleared */
ret = clear();
if (ret != 0)
return ret;
fd = open(data_file, O_RDWR);
if (fd == -1)
return fd;
reg.size = sizeof(reg);
reg.name_args = (__u64)event;
/* Register should work */
ret = ioctl(fd, DIAG_IOCSREG, &reg);
close(fd);
if (ret != 0)
return ret;
/* Ensure correct print_fmt */
ret = get_print_fmt(print_fmt, sizeof(print_fmt));
if (ret != 0)
return ret;
return strcmp(print_fmt, expected);
}
FIXTURE(user) {
int status_fd;
int data_fd;
int enable_fd;
};
FIXTURE_SETUP(user) {
self->status_fd = open(status_file, O_RDONLY);
ASSERT_NE(-1, self->status_fd);
self->data_fd = open(data_file, O_RDWR);
ASSERT_NE(-1, self->data_fd);
self->enable_fd = -1;
}
FIXTURE_TEARDOWN(user) {
close(self->status_fd);
close(self->data_fd);
if (self->enable_fd != -1) {
write(self->enable_fd, "0", sizeof("0"));
close(self->enable_fd);
}
ASSERT_EQ(0, clear());
}
TEST_F(user, register_events) {
struct user_reg reg = {0};
int page_size = sysconf(_SC_PAGESIZE);
char *status_page;
reg.size = sizeof(reg);
reg.name_args = (__u64)"__test_event u32 field1; u32 field2";
status_page = mmap(NULL, page_size, PROT_READ, MAP_SHARED,
self->status_fd, 0);
/* Register should work */
ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
ASSERT_EQ(0, reg.write_index);
ASSERT_NE(0, reg.status_bit);
/* Multiple registers should result in same index */
ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
ASSERT_EQ(0, reg.write_index);
ASSERT_NE(0, reg.status_bit);
/* Ensure disabled */
self->enable_fd = open(enable_file, O_RDWR);
ASSERT_NE(-1, self->enable_fd);
ASSERT_NE(-1, write(self->enable_fd, "0", sizeof("0")))
/* MMAP should work and be zero'd */
ASSERT_NE(MAP_FAILED, status_page);
ASSERT_NE(NULL, status_page);
ASSERT_EQ(0, status_check(status_page, reg.status_bit));
/* Enable event and ensure bits updated in status */
ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1")))
ASSERT_NE(0, status_check(status_page, reg.status_bit));
/* Disable event and ensure bits updated in status */
ASSERT_NE(-1, write(self->enable_fd, "0", sizeof("0")))
ASSERT_EQ(0, status_check(status_page, reg.status_bit));
/* File still open should return -EBUSY for delete */
ASSERT_EQ(-1, ioctl(self->data_fd, DIAG_IOCSDEL, "__test_event"));
ASSERT_EQ(EBUSY, errno);
/* Delete should work only after close */
close(self->data_fd);
self->data_fd = open(data_file, O_RDWR);
ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSDEL, "__test_event"));
/* Unmap should work */
ASSERT_EQ(0, munmap(status_page, page_size));
}
TEST_F(user, write_events) {
struct user_reg reg = {0};
struct iovec io[3];
__u32 field1, field2;
int before = 0, after = 0;
int page_size = sysconf(_SC_PAGESIZE);
char *status_page;
reg.size = sizeof(reg);
reg.name_args = (__u64)"__test_event u32 field1; u32 field2";
field1 = 1;
field2 = 2;
io[0].iov_base = &reg.write_index;
io[0].iov_len = sizeof(reg.write_index);
io[1].iov_base = &field1;
io[1].iov_len = sizeof(field1);
io[2].iov_base = &field2;
io[2].iov_len = sizeof(field2);
status_page = mmap(NULL, page_size, PROT_READ, MAP_SHARED,
self->status_fd, 0);
/* Register should work */
ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
ASSERT_EQ(0, reg.write_index);
ASSERT_NE(0, reg.status_bit);
/* MMAP should work and be zero'd */
ASSERT_NE(MAP_FAILED, status_page);
ASSERT_NE(NULL, status_page);
ASSERT_EQ(0, status_check(status_page, reg.status_bit));
/* Write should fail on invalid slot with ENOENT */
io[0].iov_base = &field2;
io[0].iov_len = sizeof(field2);
ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
ASSERT_EQ(ENOENT, errno);
io[0].iov_base = &reg.write_index;
io[0].iov_len = sizeof(reg.write_index);
/* Enable event */
self->enable_fd = open(enable_file, O_RDWR);
ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1")))
/* Event should now be enabled */
ASSERT_NE(0, status_check(status_page, reg.status_bit));
/* Write should make it out to ftrace buffers */
before = trace_bytes();
ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 3));
after = trace_bytes();
ASSERT_GT(after, before);
/* Negative index should fail with EINVAL */
reg.write_index = -1;
ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
ASSERT_EQ(EINVAL, errno);
}
TEST_F(user, write_fault) {
struct user_reg reg = {0};
struct iovec io[2];
int l = sizeof(__u64);
void *anon;
reg.size = sizeof(reg);
reg.name_args = (__u64)"__test_event u64 anon";
anon = mmap(NULL, l, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
ASSERT_NE(MAP_FAILED, anon);
io[0].iov_base = &reg.write_index;
io[0].iov_len = sizeof(reg.write_index);
io[1].iov_base = anon;
io[1].iov_len = l;
/* Register should work */
ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
ASSERT_EQ(0, reg.write_index);
ASSERT_NE(0, reg.status_bit);
/* Write should work normally */
ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 2));
/* Faulted data should zero fill and work */
ASSERT_EQ(0, madvise(anon, l, MADV_DONTNEED));
ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 2));
ASSERT_EQ(0, munmap(anon, l));
}
TEST_F(user, write_validator) {
struct user_reg reg = {0};
struct iovec io[3];
int loc, bytes;
char data[8];
int before = 0, after = 0;
int page_size = sysconf(_SC_PAGESIZE);
char *status_page;
status_page = mmap(NULL, page_size, PROT_READ, MAP_SHARED,
self->status_fd, 0);
reg.size = sizeof(reg);
reg.name_args = (__u64)"__test_event __rel_loc char[] data";
/* Register should work */
ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
ASSERT_EQ(0, reg.write_index);
ASSERT_NE(0, reg.status_bit);
/* MMAP should work and be zero'd */
ASSERT_NE(MAP_FAILED, status_page);
ASSERT_NE(NULL, status_page);
ASSERT_EQ(0, status_check(status_page, reg.status_bit));
io[0].iov_base = &reg.write_index;
io[0].iov_len = sizeof(reg.write_index);
io[1].iov_base = &loc;
io[1].iov_len = sizeof(loc);
io[2].iov_base = data;
bytes = snprintf(data, sizeof(data), "Test") + 1;
io[2].iov_len = bytes;
/* Undersized write should fail */
ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 1));
ASSERT_EQ(EINVAL, errno);
/* Enable event */
self->enable_fd = open(enable_file, O_RDWR);
ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1")))
/* Event should now be enabled */
ASSERT_NE(0, status_check(status_page, reg.status_bit));
/* Full in-bounds write should work */
before = trace_bytes();
loc = DYN_LOC(0, bytes);
ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 3));
after = trace_bytes();
ASSERT_GT(after, before);
/* Out of bounds write should fault (offset way out) */
loc = DYN_LOC(1024, bytes);
ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
ASSERT_EQ(EFAULT, errno);
/* Out of bounds write should fault (offset 1 byte out) */
loc = DYN_LOC(1, bytes);
ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
ASSERT_EQ(EFAULT, errno);
/* Out of bounds write should fault (size way out) */
loc = DYN_LOC(0, bytes + 1024);
ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
ASSERT_EQ(EFAULT, errno);
/* Out of bounds write should fault (size 1 byte out) */
loc = DYN_LOC(0, bytes + 1);
ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
ASSERT_EQ(EFAULT, errno);
/* Non-Null should fault */
memset(data, 'A', sizeof(data));
loc = DYN_LOC(0, bytes);
ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
ASSERT_EQ(EFAULT, errno);
}
TEST_F(user, print_fmt) {
int ret;
ret = check_print_fmt("__test_event __rel_loc char[] data",
"print fmt: \"data=%s\", __get_rel_str(data)");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event __data_loc char[] data",
"print fmt: \"data=%s\", __get_str(data)");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event s64 data",
"print fmt: \"data=%lld\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event u64 data",
"print fmt: \"data=%llu\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event s32 data",
"print fmt: \"data=%d\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event u32 data",
"print fmt: \"data=%u\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event int data",
"print fmt: \"data=%d\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event unsigned int data",
"print fmt: \"data=%u\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event s16 data",
"print fmt: \"data=%d\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event u16 data",
"print fmt: \"data=%u\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event short data",
"print fmt: \"data=%d\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event unsigned short data",
"print fmt: \"data=%u\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event s8 data",
"print fmt: \"data=%d\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event u8 data",
"print fmt: \"data=%u\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event char data",
"print fmt: \"data=%d\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event unsigned char data",
"print fmt: \"data=%u\", REC->data");
ASSERT_EQ(0, ret);
ret = check_print_fmt("__test_event char[4] data",
"print fmt: \"data=%s\", REC->data");
ASSERT_EQ(0, ret);
}
int main(int argc, char **argv)
{
return test_harness_run(argc, argv);
}