1 /*
2 * Copyright (c) 2024 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28 #include <arm_acle.h>
29 #include <fcntl.h>
30 #include <mach/mach.h>
31 #include <mach/mach_vm.h>
32 #include <libproc.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <sys/mman.h>
36 #include <unistd.h>
37
38 #include "arm_mte_utilities.h"
39
40 static void
assert_posix_success(int ret,char * msg)41 assert_posix_success(int ret, char *msg)
42 {
43 if (ret == -1) {
44 fprintf(stderr, "error in process being debugged: %s\n", msg);
45 exit(1);
46 }
47 }
48
49 /*
50 * This program is used by the mte_debugger_untagged_copyio test in
51 * arm_mte_unentitled.c. In this setup, the test is the "debugger" and this code
52 * is the "program being debugged".
53 */
54 int
main(int argc,char * argv[])55 main(int argc, char *argv[])
56 {
57 if (argc != 2) {
58 fprintf(stderr, "usage: arm_mte_debugger_helper shm_name\n");
59 fprintf(stderr, "this is intended to be called from test code\n");
60 exit(1);
61 }
62 int ret;
63 struct proc_bsdinfo bsd_info;
64 ret = proc_pidinfo(getpid(), PROC_PIDTBSDINFO, 0, &bsd_info, sizeof(bsd_info));
65 if (ret != sizeof(bsd_info)) {
66 fprintf(stderr, "PROC_PIDTBSDINFO");
67 exit(1);
68 }
69 if (!(bsd_info.pbi_flags & PROC_FLAG_SEC_ENABLED)) {
70 fprintf(stderr, "arm_mte_debugger_helper launched without MTE enabled");
71 exit(1);
72 }
73
74 char *shm_name = argv[1];
75 int fd = shm_open(shm_name, O_RDWR);
76 assert_posix_success(fd, "shm_open");
77
78 vm_address_t *shm = mmap(NULL, sizeof(vm_address_t), PROT_READ | PROT_WRITE,
79 MAP_SHARED, fd, 0);
80 if ((void*) shm == MAP_FAILED) {
81 fprintf(stderr, "mmap");
82 exit(1);
83 }
84
85 /* the test will tell us how much memory to allocate via the shared memory */
86 const vm_size_t ALLOC_SIZE = (mach_vm_size_t) *shm;
87
88 /* allocate some tagged memory */
89 vm_address_t addr = 0;
90 kern_return_t kr = vm_allocate(mach_task_self(), &addr, ALLOC_SIZE,
91 VM_FLAGS_ANYWHERE | VM_FLAGS_MTE);
92 if (kr != KERN_SUCCESS) {
93 fprintf(stderr, "vm_allocate");
94 exit(1);
95 }
96
97 /* write some tags and data */
98 uint64_t mask = __arm_mte_exclude_tag((void*) addr, 0);
99 uint8_t *tagged_ptr = __arm_mte_create_random_tag((void*) addr, mask);
100 for (vm_size_t i = 0; i < ALLOC_SIZE; i += MTE_GRANULE_SIZE) {
101 __arm_mte_set_tag(tagged_ptr + i);
102 }
103 memset(tagged_ptr, 'A', ALLOC_SIZE);
104
105 /* send the tagged memory's address back to the "debugger" so it can remap it */
106 *shm = addr;
107 msync((void*) shm, sizeof(vm_address_t), MS_SYNC | MS_INVALIDATE);
108
109 ret = close(fd);
110 assert_posix_success(ret, "close");
111
112 /* when the parent process dies, the child will be given to launchd (pid=1) */
113 while (getppid() != 1) {
114 /* we need to keep the process alive so the memory doesn't go away */
115 sleep(1);
116 }
117 }
118