// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2016 Google, Inc.
*
* Original Code by Pavel Labath <[email protected]>
*
* Code modified by Pratyush Anand <[email protected]>
* for testing different byte select for each access size.
*/
#define _GNU_SOURCE
#include <asm/ptrace.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/ptrace.h>
#include <sys/param.h>
#include <sys/uio.h>
#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <elf.h>
#include <errno.h>
#include <signal.h>
#include "../kselftest.h"
static volatile uint8_t var[96] __attribute__((__aligned__(32)));
static void child(int size, int wr)
{
volatile uint8_t *addr = &var[32 + wr];
if (ptrace(PTRACE_TRACEME, 0, NULL, NULL) != 0) {
ksft_print_msg(
"ptrace(PTRACE_TRACEME) failed: %s\n",
strerror(errno));
_exit(1);
}
if (raise(SIGSTOP) != 0) {
ksft_print_msg(
"raise(SIGSTOP) failed: %s\n", strerror(errno));
_exit(1);
}
if ((uintptr_t) addr % size) {
ksft_print_msg(
"Wrong address write for the given size: %s\n",
strerror(errno));
_exit(1);
}
switch (size) {
case 1:
*addr = 47;
break;
case 2:
*(uint16_t *)addr = 47;
break;
case 4:
*(uint32_t *)addr = 47;
break;
case 8:
*(uint64_t *)addr = 47;
break;
case 16:
__asm__ volatile ("stp x29, x30, %0" : "=m" (addr[0]));
break;
case 32:
__asm__ volatile ("stp q29, q30, %0" : "=m" (addr[0]));
break;
}
_exit(0);
}
static bool set_watchpoint(pid_t pid, int size, int wp)
{
const volatile uint8_t *addr = &var[32 + wp];
const int offset = (uintptr_t)addr % 8;
const unsigned int byte_mask = ((1 << size) - 1) << offset;
const unsigned int type = 2; /* Write */
const unsigned int enable = 1;
const unsigned int control = byte_mask << 5 | type << 3 | enable;
struct user_hwdebug_state dreg_state;
struct iovec iov;
memset(&dreg_state, 0, sizeof(dreg_state));
dreg_state.dbg_regs[0].addr = (uintptr_t)(addr - offset);
dreg_state.dbg_regs[0].ctrl = control;
iov.iov_base = &dreg_state;
iov.iov_len = offsetof(struct user_hwdebug_state, dbg_regs) +
sizeof(dreg_state.dbg_regs[0]);
if (ptrace(PTRACE_SETREGSET, pid, NT_ARM_HW_WATCH, &iov) == 0)
return true;
if (errno == EIO)
ksft_print_msg(
"ptrace(PTRACE_SETREGSET, NT_ARM_HW_WATCH) not supported on this hardware: %s\n",
strerror(errno));
ksft_print_msg(
"ptrace(PTRACE_SETREGSET, NT_ARM_HW_WATCH) failed: %s\n",
strerror(errno));
return false;
}
static bool run_test(int wr_size, int wp_size, int wr, int wp)
{
int status;
siginfo_t siginfo;
pid_t pid = fork();
pid_t wpid;
if (pid < 0) {
ksft_test_result_fail(
"fork() failed: %s\n", strerror(errno));
return false;
}
if (pid == 0)
child(wr_size, wr);
wpid = waitpid(pid, &status, __WALL);
if (wpid != pid) {
ksft_print_msg(
"waitpid() failed: %s\n", strerror(errno));
return false;
}
if (!WIFSTOPPED(status)) {
ksft_print_msg(
"child did not stop: %s\n", strerror(errno));
return false;
}
if (WSTOPSIG(status) != SIGSTOP) {
ksft_print_msg("child did not stop with SIGSTOP\n");
return false;
}
if (!set_watchpoint(pid, wp_size, wp))
return false;
if (ptrace(PTRACE_CONT, pid, NULL, NULL) < 0) {
ksft_print_msg(
"ptrace(PTRACE_CONT) failed: %s\n",
strerror(errno));
return false;
}
alarm(3);
wpid = waitpid(pid, &status, __WALL);
if (wpid != pid) {
ksft_print_msg(
"waitpid() failed: %s\n", strerror(errno));
return false;
}
alarm(0);
if (WIFEXITED(status)) {
ksft_print_msg("child exited prematurely\n");
return false;
}
if (!WIFSTOPPED(status)) {
ksft_print_msg("child did not stop\n");
return false;
}
if (WSTOPSIG(status) != SIGTRAP) {
ksft_print_msg("child did not stop with SIGTRAP\n");
return false;
}
if (ptrace(PTRACE_GETSIGINFO, pid, NULL, &siginfo) != 0) {
ksft_print_msg(
"ptrace(PTRACE_GETSIGINFO): %s\n",
strerror(errno));
return false;
}
if (siginfo.si_code != TRAP_HWBKPT) {
ksft_print_msg(
"Unexpected si_code %d\n", siginfo.si_code);
return false;
}
kill(pid, SIGKILL);
wpid = waitpid(pid, &status, 0);
if (wpid != pid) {
ksft_print_msg(
"waitpid() failed: %s\n", strerror(errno));
return false;
}
return true;
}
static void sigalrm(int sig)
{
}
int main(int argc, char **argv)
{
int opt;
bool succeeded = true;
struct sigaction act;
int wr, wp, size;
bool result;
ksft_print_header();
ksft_set_plan(213);
act.sa_handler = sigalrm;
sigemptyset(&act.sa_mask);
act.sa_flags = 0;
sigaction(SIGALRM, &act, NULL);
for (size = 1; size <= 32; size = size*2) {
for (wr = 0; wr <= 32; wr = wr + size) {
for (wp = wr - size; wp <= wr + size; wp = wp + size) {
result = run_test(size, MIN(size, 8), wr, wp);
if ((result && wr == wp) ||
(!result && wr != wp))
ksft_test_result_pass(
"Test size = %d write offset = %d watchpoint offset = %d\n",
size, wr, wp);
else {
ksft_test_result_fail(
"Test size = %d write offset = %d watchpoint offset = %d\n",
size, wr, wp);
succeeded = false;
}
}
}
}
for (size = 1; size <= 32; size = size*2) {
if (run_test(size, 8, -size, -8))
ksft_test_result_pass(
"Test size = %d write offset = %d watchpoint offset = -8\n",
size, -size);
else {
ksft_test_result_fail(
"Test size = %d write offset = %d watchpoint offset = -8\n",
size, -size);
succeeded = false;
}
}
if (succeeded)
ksft_exit_pass();
else
ksft_exit_fail();
}
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