1// SPDX-License-Identifier: GPL-2.0
  2
  3/*
  4 * Copyright (C) 2020 Google LLC.
  5 */
  6
  7#include <test_progs.h>
  8#include <sys/mman.h>
  9#include <sys/wait.h>
 10#include <unistd.h>
 11#include <malloc.h>
 12#include <stdlib.h>
 13
 14#include "lsm.skel.h"
 15
 16char *CMD_ARGS[] = {"true", NULL};
 17
 18#define GET_PAGE_ADDR(ADDR, PAGE_SIZE)					\
 19	(char *)(((unsigned long) (ADDR + PAGE_SIZE)) & ~(PAGE_SIZE-1))
 20
 21int stack_mprotect(void)
 22{
 23	void *buf;
 24	long sz;
 25	int ret;
 26
 27	sz = sysconf(_SC_PAGESIZE);
 28	if (sz < 0)
 29		return sz;
 30
 31	buf = alloca(sz * 3);
 32	ret = mprotect(GET_PAGE_ADDR(buf, sz), sz,
 33		       PROT_READ | PROT_WRITE | PROT_EXEC);
 34	return ret;
 35}
 36
 37int exec_cmd(int *monitored_pid)
 38{
 39	int child_pid, child_status;
 40
 41	child_pid = fork();
 42	if (child_pid == 0) {
 43		*monitored_pid = getpid();
 44		execvp(CMD_ARGS[0], CMD_ARGS);
 45		return -EINVAL;
 46	} else if (child_pid > 0) {
 47		waitpid(child_pid, &child_status, 0);
 48		return child_status;
 49	}
 50
 51	return -EINVAL;
 52}
 53
 54static int test_lsm(struct lsm *skel)
 55{
 56	struct bpf_link *link;
 57	int buf = 1234;
 58	int err;
 59
 60	err = lsm__attach(skel);
 61	if (!ASSERT_OK(err, "attach"))
 62		return err;
 63
 64	/* Check that already linked program can't be attached again. */
 65	link = bpf_program__attach(skel->progs.test_int_hook);
 66	if (!ASSERT_ERR_PTR(link, "attach_link"))
 67		return -1;
 68
 69	err = exec_cmd(&skel->bss->monitored_pid);
 70	if (!ASSERT_OK(err, "exec_cmd"))
 71		return err;
 72
 73	ASSERT_EQ(skel->bss->bprm_count, 1, "bprm_count");
 
 74
 75	skel->bss->monitored_pid = getpid();
 76
 77	err = stack_mprotect();
 78	if (!ASSERT_EQ(errno, EPERM, "stack_mprotect"))
 79		return err;
 80
 81	ASSERT_EQ(skel->bss->mprotect_count, 1, "mprotect_count");
 82
 83	syscall(__NR_setdomainname, &buf, -2L);
 84	syscall(__NR_setdomainname, 0, -3L);
 85	syscall(__NR_setdomainname, ~0L, -4L);
 86
 87	ASSERT_EQ(skel->bss->copy_test, 3, "copy_test");
 88
 89	lsm__detach(skel);
 90
 91	skel->bss->copy_test = 0;
 92	skel->bss->bprm_count = 0;
 93	skel->bss->mprotect_count = 0;
 94	return 0;
 95}
 96
 97void test_test_lsm(void)
 98{
 99	struct lsm *skel = NULL;
100	int err;
101
102	skel = lsm__open_and_load();
103	if (!ASSERT_OK_PTR(skel, "lsm_skel_load"))
104		goto close_prog;
105
106	err = test_lsm(skel);
107	if (!ASSERT_OK(err, "test_lsm_first_attach"))
108		goto close_prog;
109
110	err = test_lsm(skel);
111	ASSERT_OK(err, "test_lsm_second_attach");
112
113close_prog:
114	lsm__destroy(skel);
115}

 1// SPDX-License-Identifier: GPL-2.0
 2
 3/*
 4 * Copyright (C) 2020 Google LLC.
 5 */
 6
 7#include <test_progs.h>
 8#include <sys/mman.h>
 9#include <sys/wait.h>
10#include <unistd.h>
11#include <malloc.h>
12#include <stdlib.h>
13
14#include "lsm.skel.h"
15
16char *CMD_ARGS[] = {"true", NULL};
17
18#define GET_PAGE_ADDR(ADDR, PAGE_SIZE)					\
19	(char *)(((unsigned long) (ADDR + PAGE_SIZE)) & ~(PAGE_SIZE-1))
20
21int stack_mprotect(void)
22{
23	void *buf;
24	long sz;
25	int ret;
26
27	sz = sysconf(_SC_PAGESIZE);
28	if (sz < 0)
29		return sz;
30
31	buf = alloca(sz * 3);
32	ret = mprotect(GET_PAGE_ADDR(buf, sz), sz,
33		       PROT_READ | PROT_WRITE | PROT_EXEC);
34	return ret;
35}
36
37int exec_cmd(int *monitored_pid)
38{
39	int child_pid, child_status;
40
41	child_pid = fork();
42	if (child_pid == 0) {
43		*monitored_pid = getpid();
44		execvp(CMD_ARGS[0], CMD_ARGS);
45		return -EINVAL;
46	} else if (child_pid > 0) {
47		waitpid(child_pid, &child_status, 0);
48		return child_status;
49	}
50
51	return -EINVAL;
52}
53
54void test_test_lsm(void)
55{
56	struct lsm *skel = NULL;
57	int err, duration = 0;
 
58
59	skel = lsm__open_and_load();
60	if (CHECK(!skel, "skel_load", "lsm skeleton failed\n"))
61		goto close_prog;
62
63	err = lsm__attach(skel);
64	if (CHECK(err, "attach", "lsm attach failed: %d\n", err))
65		goto close_prog;
 
66
67	err = exec_cmd(&skel->bss->monitored_pid);
68	if (CHECK(err < 0, "exec_cmd", "err %d errno %d\n", err, errno))
69		goto close_prog;
70
71	CHECK(skel->bss->bprm_count != 1, "bprm_count", "bprm_count = %d\n",
72	      skel->bss->bprm_count);
73
74	skel->bss->monitored_pid = getpid();
75
76	err = stack_mprotect();
77	if (CHECK(errno != EPERM, "stack_mprotect", "want err=EPERM, got %d\n",
78		  errno))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
79		goto close_prog;
80
81	CHECK(skel->bss->mprotect_count != 1, "mprotect_count",
82	      "mprotect_count = %d\n", skel->bss->mprotect_count);
83
84close_prog:
85	lsm__destroy(skel);
86}