1// SPDX-License-Identifier: GPL-2.0
2// Copyright (C) 2020 ARM Limited
3
4#define _GNU_SOURCE
5
6#include <errno.h>
7#include <pthread.h>
8#include <stdint.h>
9#include <stdio.h>
10#include <stdlib.h>
11#include <time.h>
12#include <unistd.h>
13#include <sys/auxv.h>
14#include <sys/mman.h>
15#include <sys/prctl.h>
16#include <sys/types.h>
17#include <sys/wait.h>
18
19#include "kselftest.h"
20#include "mte_common_util.h"
21
22#include "mte_def.h"
23
24#define NUM_ITERATIONS		1024
25#define MAX_THREADS		5
26#define THREAD_ITERATIONS	1000
27
28void *execute_thread(void *x)
29{
30	pid_t pid = *((pid_t *)x);
31	pid_t tid = gettid();
32	uint64_t prctl_tag_mask;
33	uint64_t prctl_set;
34	uint64_t prctl_get;
35	uint64_t prctl_tcf;
36
37	srand(time(NULL) ^ (pid << 16) ^ (tid << 16));
38
39	prctl_tag_mask = rand() & 0xffff;
40
41	if (prctl_tag_mask % 2)
42		prctl_tcf = PR_MTE_TCF_SYNC;
43	else
44		prctl_tcf = PR_MTE_TCF_ASYNC;
45
46	prctl_set = PR_TAGGED_ADDR_ENABLE | prctl_tcf | (prctl_tag_mask << PR_MTE_TAG_SHIFT);
47
48	for (int j = 0; j < THREAD_ITERATIONS; j++) {
49		if (prctl(PR_SET_TAGGED_ADDR_CTRL, prctl_set, 0, 0, 0)) {
50			perror("prctl() failed");
51			goto fail;
52		}
53
54		prctl_get = prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0);
55
56		if (prctl_set != prctl_get) {
57			ksft_print_msg("Error: prctl_set: 0x%lx != prctl_get: 0x%lx\n",
58						prctl_set, prctl_get);
59			goto fail;
60		}
61	}
62
63	return (void *)KSFT_PASS;
64
65fail:
66	return (void *)KSFT_FAIL;
67}
68
69int execute_test(pid_t pid)
70{
71	pthread_t thread_id[MAX_THREADS];
72	int thread_data[MAX_THREADS];
73
74	for (int i = 0; i < MAX_THREADS; i++)
75		pthread_create(&thread_id[i], NULL,
76			       execute_thread, (void *)&pid);
77
78	for (int i = 0; i < MAX_THREADS; i++)
79		pthread_join(thread_id[i], (void *)&thread_data[i]);
80
81	for (int i = 0; i < MAX_THREADS; i++)
82		if (thread_data[i] == KSFT_FAIL)
83			return KSFT_FAIL;
84
85	return KSFT_PASS;
86}
87
88int mte_gcr_fork_test(void)
89{
90	pid_t pid;
91	int results[NUM_ITERATIONS];
92	pid_t cpid;
93	int res;
94
95	for (int i = 0; i < NUM_ITERATIONS; i++) {
96		pid = fork();
97
98		if (pid < 0)
99			return KSFT_FAIL;
100
101		if (pid == 0) {
102			cpid = getpid();
103
104			res = execute_test(cpid);
105
106			exit(res);
107		}
108	}
109
110	for (int i = 0; i < NUM_ITERATIONS; i++) {
111		wait(&res);
112
113		if (WIFEXITED(res))
114			results[i] = WEXITSTATUS(res);
115		else
116			--i;
117	}
118
119	for (int i = 0; i < NUM_ITERATIONS; i++)
120		if (results[i] == KSFT_FAIL)
121			return KSFT_FAIL;
122
123	return KSFT_PASS;
124}
125
126int main(int argc, char *argv[])
127{
128	int err;
129
130	err = mte_default_setup();
131	if (err)
132		return err;
133
134	ksft_set_plan(1);
135
136	evaluate_test(mte_gcr_fork_test(),
137		"Verify that GCR_EL1 is set correctly on context switch\n");
138
139	mte_restore_setup();
140	ksft_print_cnts();
141
142	return ksft_get_fail_cnt() == 0 ? KSFT_PASS : KSFT_FAIL;
143}
144