// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2020 ARM Limited
#include <fcntl.h>
#include <sched.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <linux/auxvec.h>
#include <sys/auxv.h>
#include <sys/mman.h>
#include <sys/prctl.h>
#include <asm/hwcap.h>
#include "kselftest.h"
#include "mte_common_util.h"
#include "mte_def.h"
#define INIT_BUFFER_SIZE 256
struct mte_fault_cxt cur_mte_cxt;
static unsigned int mte_cur_mode;
static unsigned int mte_cur_pstate_tco;
void mte_default_handler(int signum, siginfo_t *si, void *uc)
{
unsigned long addr = (unsigned long)si->si_addr;
if (signum == SIGSEGV) {
#ifdef DEBUG
ksft_print_msg("INFO: SIGSEGV signal at pc=%lx, fault addr=%lx, si_code=%lx\n",
((ucontext_t *)uc)->uc_mcontext.pc, addr, si->si_code);
#endif
if (si->si_code == SEGV_MTEAERR) {
if (cur_mte_cxt.trig_si_code == si->si_code)
cur_mte_cxt.fault_valid = true;
else
ksft_print_msg("Got unexpected SEGV_MTEAERR at pc=$lx, fault addr=%lx\n",
((ucontext_t *)uc)->uc_mcontext.pc,
addr);
return;
}
/* Compare the context for precise error */
else if (si->si_code == SEGV_MTESERR) {
if (cur_mte_cxt.trig_si_code == si->si_code &&
((cur_mte_cxt.trig_range >= 0 &&
addr >= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) &&
addr <= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)) ||
(cur_mte_cxt.trig_range < 0 &&
addr <= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) &&
addr >= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)))) {
cur_mte_cxt.fault_valid = true;
/* Adjust the pc by 4 */
((ucontext_t *)uc)->uc_mcontext.pc += 4;
} else {
ksft_print_msg("Invalid MTE synchronous exception caught!\n");
exit(1);
}
} else {
ksft_print_msg("Unknown SIGSEGV exception caught!\n");
exit(1);
}
} else if (signum == SIGBUS) {
ksft_print_msg("INFO: SIGBUS signal at pc=%lx, fault addr=%lx, si_code=%lx\n",
((ucontext_t *)uc)->uc_mcontext.pc, addr, si->si_code);
if ((cur_mte_cxt.trig_range >= 0 &&
addr >= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) &&
addr <= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)) ||
(cur_mte_cxt.trig_range < 0 &&
addr <= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) &&
addr >= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range))) {
cur_mte_cxt.fault_valid = true;
/* Adjust the pc by 4 */
((ucontext_t *)uc)->uc_mcontext.pc += 4;
}
}
}
void mte_register_signal(int signal, void (*handler)(int, siginfo_t *, void *))
{
struct sigaction sa;
sa.sa_sigaction = handler;
sa.sa_flags = SA_SIGINFO;
sigemptyset(&sa.sa_mask);
sigaction(signal, &sa, NULL);
}
void mte_wait_after_trig(void)
{
sched_yield();
}
void *mte_insert_tags(void *ptr, size_t size)
{
void *tag_ptr;
int align_size;
if (!ptr || (unsigned long)(ptr) & MT_ALIGN_GRANULE) {
ksft_print_msg("FAIL: Addr=%lx: invalid\n", ptr);
return NULL;
}
align_size = MT_ALIGN_UP(size);
tag_ptr = mte_insert_random_tag(ptr);
mte_set_tag_address_range(tag_ptr, align_size);
return tag_ptr;
}
void mte_clear_tags(void *ptr, size_t size)
{
if (!ptr || (unsigned long)(ptr) & MT_ALIGN_GRANULE) {
ksft_print_msg("FAIL: Addr=%lx: invalid\n", ptr);
return;
}
size = MT_ALIGN_UP(size);
ptr = (void *)MT_CLEAR_TAG((unsigned long)ptr);
mte_clear_tag_address_range(ptr, size);
}
static void *__mte_allocate_memory_range(size_t size, int mem_type, int mapping,
size_t range_before, size_t range_after,
bool tags, int fd)
{
void *ptr;
int prot_flag, map_flag;
size_t entire_size = size + range_before + range_after;
switch (mem_type) {
case USE_MALLOC:
return malloc(entire_size) + range_before;
case USE_MMAP:
case USE_MPROTECT:
break;
default:
ksft_print_msg("FAIL: Invalid allocate request\n");
return NULL;
}
prot_flag = PROT_READ | PROT_WRITE;
if (mem_type == USE_MMAP)
prot_flag |= PROT_MTE;
map_flag = mapping;
if (fd == -1)
map_flag = MAP_ANONYMOUS | map_flag;
if (!(mapping & MAP_SHARED))
map_flag |= MAP_PRIVATE;
ptr = mmap(NULL, entire_size, prot_flag, map_flag, fd, 0);
if (ptr == MAP_FAILED) {
ksft_print_msg("FAIL: mmap allocation\n");
return NULL;
}
if (mem_type == USE_MPROTECT) {
if (mprotect(ptr, entire_size, prot_flag | PROT_MTE)) {
munmap(ptr, size);
ksft_print_msg("FAIL: mprotect PROT_MTE property\n");
return NULL;
}
}
if (tags)
ptr = mte_insert_tags(ptr + range_before, size);
return ptr;
}
void *mte_allocate_memory_tag_range(size_t size, int mem_type, int mapping,
size_t range_before, size_t range_after)
{
return __mte_allocate_memory_range(size, mem_type, mapping, range_before,
range_after, true, -1);
}
void *mte_allocate_memory(size_t size, int mem_type, int mapping, bool tags)
{
return __mte_allocate_memory_range(size, mem_type, mapping, 0, 0, tags, -1);
}
void *mte_allocate_file_memory(size_t size, int mem_type, int mapping, bool tags, int fd)
{
int index;
char buffer[INIT_BUFFER_SIZE];
if (mem_type != USE_MPROTECT && mem_type != USE_MMAP) {
ksft_print_msg("FAIL: Invalid mmap file request\n");
return NULL;
}
/* Initialize the file for mappable size */
lseek(fd, 0, SEEK_SET);
for (index = INIT_BUFFER_SIZE; index < size; index += INIT_BUFFER_SIZE) {
if (write(fd, buffer, INIT_BUFFER_SIZE) != INIT_BUFFER_SIZE) {
perror("initialising buffer");
return NULL;
}
}
index -= INIT_BUFFER_SIZE;
if (write(fd, buffer, size - index) != size - index) {
perror("initialising buffer");
return NULL;
}
return __mte_allocate_memory_range(size, mem_type, mapping, 0, 0, tags, fd);
}
void *mte_allocate_file_memory_tag_range(size_t size, int mem_type, int mapping,
size_t range_before, size_t range_after, int fd)
{
int index;
char buffer[INIT_BUFFER_SIZE];
int map_size = size + range_before + range_after;
if (mem_type != USE_MPROTECT && mem_type != USE_MMAP) {
ksft_print_msg("FAIL: Invalid mmap file request\n");
return NULL;
}
/* Initialize the file for mappable size */
lseek(fd, 0, SEEK_SET);
for (index = INIT_BUFFER_SIZE; index < map_size; index += INIT_BUFFER_SIZE)
if (write(fd, buffer, INIT_BUFFER_SIZE) != INIT_BUFFER_SIZE) {
perror("initialising buffer");
return NULL;
}
index -= INIT_BUFFER_SIZE;
if (write(fd, buffer, map_size - index) != map_size - index) {
perror("initialising buffer");
return NULL;
}
return __mte_allocate_memory_range(size, mem_type, mapping, range_before,
range_after, true, fd);
}
static void __mte_free_memory_range(void *ptr, size_t size, int mem_type,
size_t range_before, size_t range_after, bool tags)
{
switch (mem_type) {
case USE_MALLOC:
free(ptr - range_before);
break;
case USE_MMAP:
case USE_MPROTECT:
if (tags)
mte_clear_tags(ptr, size);
munmap(ptr - range_before, size + range_before + range_after);
break;
default:
ksft_print_msg("FAIL: Invalid free request\n");
break;
}
}
void mte_free_memory_tag_range(void *ptr, size_t size, int mem_type,
size_t range_before, size_t range_after)
{
__mte_free_memory_range(ptr, size, mem_type, range_before, range_after, true);
}
void mte_free_memory(void *ptr, size_t size, int mem_type, bool tags)
{
__mte_free_memory_range(ptr, size, mem_type, 0, 0, tags);
}
void mte_initialize_current_context(int mode, uintptr_t ptr, ssize_t range)
{
cur_mte_cxt.fault_valid = false;
cur_mte_cxt.trig_addr = ptr;
cur_mte_cxt.trig_range = range;
if (mode == MTE_SYNC_ERR)
cur_mte_cxt.trig_si_code = SEGV_MTESERR;
else if (mode == MTE_ASYNC_ERR)
cur_mte_cxt.trig_si_code = SEGV_MTEAERR;
else
cur_mte_cxt.trig_si_code = 0;
}
int mte_switch_mode(int mte_option, unsigned long incl_mask)
{
unsigned long en = 0;
switch (mte_option) {
case MTE_NONE_ERR:
case MTE_SYNC_ERR:
case MTE_ASYNC_ERR:
break;
default:
ksft_print_msg("FAIL: Invalid MTE option %x\n", mte_option);
return -EINVAL;
}
if (incl_mask & ~MT_INCLUDE_TAG_MASK) {
ksft_print_msg("FAIL: Invalid incl_mask %lx\n", incl_mask);
return -EINVAL;
}
en = PR_TAGGED_ADDR_ENABLE;
switch (mte_option) {
case MTE_SYNC_ERR:
en |= PR_MTE_TCF_SYNC;
break;
case MTE_ASYNC_ERR:
en |= PR_MTE_TCF_ASYNC;
break;
case MTE_NONE_ERR:
en |= PR_MTE_TCF_NONE;
break;
}
en |= (incl_mask << PR_MTE_TAG_SHIFT);
/* Enable address tagging ABI, mte error reporting mode and tag inclusion mask. */
if (prctl(PR_SET_TAGGED_ADDR_CTRL, en, 0, 0, 0) != 0) {
ksft_print_msg("FAIL:prctl PR_SET_TAGGED_ADDR_CTRL for mte mode\n");
return -EINVAL;
}
return 0;
}
int mte_default_setup(void)
{
unsigned long hwcaps2 = getauxval(AT_HWCAP2);
unsigned long en = 0;
int ret;
if (!(hwcaps2 & HWCAP2_MTE)) {
ksft_print_msg("SKIP: MTE features unavailable\n");
return KSFT_SKIP;
}
/* Get current mte mode */
ret = prctl(PR_GET_TAGGED_ADDR_CTRL, en, 0, 0, 0);
if (ret < 0) {
ksft_print_msg("FAIL:prctl PR_GET_TAGGED_ADDR_CTRL with error =%d\n", ret);
return KSFT_FAIL;
}
if (ret & PR_MTE_TCF_SYNC)
mte_cur_mode = MTE_SYNC_ERR;
else if (ret & PR_MTE_TCF_ASYNC)
mte_cur_mode = MTE_ASYNC_ERR;
else if (ret & PR_MTE_TCF_NONE)
mte_cur_mode = MTE_NONE_ERR;
mte_cur_pstate_tco = mte_get_pstate_tco();
/* Disable PSTATE.TCO */
mte_disable_pstate_tco();
return 0;
}
void mte_restore_setup(void)
{
mte_switch_mode(mte_cur_mode, MTE_ALLOW_NON_ZERO_TAG);
if (mte_cur_pstate_tco == MT_PSTATE_TCO_EN)
mte_enable_pstate_tco();
else if (mte_cur_pstate_tco == MT_PSTATE_TCO_DIS)
mte_disable_pstate_tco();
}
int create_temp_file(void)
{
int fd;
char filename[] = "/dev/shm/tmp_XXXXXX";
/* Create a file in the tmpfs filesystem */
fd = mkstemp(&filename[0]);
if (fd == -1) {
perror(filename);
ksft_print_msg("FAIL: Unable to open temporary file\n");
return 0;
}
unlink(&filename[0]);
return fd;
}
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