1 // SPDX-License-Identifier: GPL-2.0
2 #define _GNU_SOURCE
3 #include <test_progs.h>
4 #include <sys/stat.h>
5 #include <linux/sched.h>
6 #include <sys/syscall.h>
7
8 #define MAX_PATH_LEN 128
9 #define MAX_FILES 7
10
11 #include "test_d_path.skel.h"
12 #include "test_d_path_check_rdonly_mem.skel.h"
13 #include "test_d_path_check_types.skel.h"
14
15 static int duration;
16
17 static struct {
18 __u32 cnt;
19 char paths[MAX_FILES][MAX_PATH_LEN];
20 } src;
21
set_pathname(int fd,pid_t pid)22 static int set_pathname(int fd, pid_t pid)
23 {
24 char buf[MAX_PATH_LEN];
25
26 snprintf(buf, MAX_PATH_LEN, "/proc/%d/fd/%d", pid, fd);
27 return readlink(buf, src.paths[src.cnt++], MAX_PATH_LEN);
28 }
29
trigger_fstat_events(pid_t pid)30 static int trigger_fstat_events(pid_t pid)
31 {
32 int sockfd = -1, procfd = -1, devfd = -1;
33 int localfd = -1, indicatorfd = -1;
34 int pipefd[2] = { -1, -1 };
35 struct stat fileStat;
36 int ret = -1;
37
38 /* unmountable pseudo-filesystems */
39 if (CHECK(pipe(pipefd) < 0, "trigger", "pipe failed\n"))
40 return ret;
41 /* unmountable pseudo-filesystems */
42 sockfd = socket(AF_INET, SOCK_STREAM, 0);
43 if (CHECK(sockfd < 0, "trigger", "socket failed\n"))
44 goto out_close;
45 /* mountable pseudo-filesystems */
46 procfd = open("/proc/self/comm", O_RDONLY);
47 if (CHECK(procfd < 0, "trigger", "open /proc/self/comm failed\n"))
48 goto out_close;
49 devfd = open("/dev/urandom", O_RDONLY);
50 if (CHECK(devfd < 0, "trigger", "open /dev/urandom failed\n"))
51 goto out_close;
52 localfd = open("/tmp/d_path_loadgen.txt", O_CREAT | O_RDONLY, 0644);
53 if (CHECK(localfd < 0, "trigger", "open /tmp/d_path_loadgen.txt failed\n"))
54 goto out_close;
55 /* bpf_d_path will return path with (deleted) */
56 remove("/tmp/d_path_loadgen.txt");
57 indicatorfd = open("/tmp/", O_PATH);
58 if (CHECK(indicatorfd < 0, "trigger", "open /tmp/ failed\n"))
59 goto out_close;
60
61 ret = set_pathname(pipefd[0], pid);
62 if (CHECK(ret < 0, "trigger", "set_pathname failed for pipe[0]\n"))
63 goto out_close;
64 ret = set_pathname(pipefd[1], pid);
65 if (CHECK(ret < 0, "trigger", "set_pathname failed for pipe[1]\n"))
66 goto out_close;
67 ret = set_pathname(sockfd, pid);
68 if (CHECK(ret < 0, "trigger", "set_pathname failed for socket\n"))
69 goto out_close;
70 ret = set_pathname(procfd, pid);
71 if (CHECK(ret < 0, "trigger", "set_pathname failed for proc\n"))
72 goto out_close;
73 ret = set_pathname(devfd, pid);
74 if (CHECK(ret < 0, "trigger", "set_pathname failed for dev\n"))
75 goto out_close;
76 ret = set_pathname(localfd, pid);
77 if (CHECK(ret < 0, "trigger", "set_pathname failed for file\n"))
78 goto out_close;
79 ret = set_pathname(indicatorfd, pid);
80 if (CHECK(ret < 0, "trigger", "set_pathname failed for dir\n"))
81 goto out_close;
82
83 /* triggers vfs_getattr */
84 fstat(pipefd[0], &fileStat);
85 fstat(pipefd[1], &fileStat);
86 fstat(sockfd, &fileStat);
87 fstat(procfd, &fileStat);
88 fstat(devfd, &fileStat);
89 fstat(localfd, &fileStat);
90 fstat(indicatorfd, &fileStat);
91
92 out_close:
93 /* triggers filp_close */
94 close(pipefd[0]);
95 close(pipefd[1]);
96 close(sockfd);
97 close(procfd);
98 close(devfd);
99 close(localfd);
100 close(indicatorfd);
101 return ret;
102 }
103
test_d_path_basic(void)104 static void test_d_path_basic(void)
105 {
106 struct test_d_path__bss *bss;
107 struct test_d_path *skel;
108 int err;
109
110 skel = test_d_path__open_and_load();
111 if (CHECK(!skel, "setup", "d_path skeleton failed\n"))
112 goto cleanup;
113
114 err = test_d_path__attach(skel);
115 if (CHECK(err, "setup", "attach failed: %d\n", err))
116 goto cleanup;
117
118 bss = skel->bss;
119 bss->my_pid = getpid();
120
121 err = trigger_fstat_events(bss->my_pid);
122 if (err < 0)
123 goto cleanup;
124
125 if (CHECK(!bss->called_stat,
126 "stat",
127 "trampoline for security_inode_getattr was not called\n"))
128 goto cleanup;
129
130 if (CHECK(!bss->called_close,
131 "close",
132 "trampoline for filp_close was not called\n"))
133 goto cleanup;
134
135 for (int i = 0; i < MAX_FILES; i++) {
136 CHECK(strncmp(src.paths[i], bss->paths_stat[i], MAX_PATH_LEN),
137 "check",
138 "failed to get stat path[%d]: %s vs %s\n",
139 i, src.paths[i], bss->paths_stat[i]);
140 CHECK(strncmp(src.paths[i], bss->paths_close[i], MAX_PATH_LEN),
141 "check",
142 "failed to get close path[%d]: %s vs %s\n",
143 i, src.paths[i], bss->paths_close[i]);
144 /* The d_path helper returns size plus NUL char, hence + 1 */
145 CHECK(bss->rets_stat[i] != strlen(bss->paths_stat[i]) + 1,
146 "check",
147 "failed to match stat return [%d]: %d vs %zd [%s]\n",
148 i, bss->rets_stat[i], strlen(bss->paths_stat[i]) + 1,
149 bss->paths_stat[i]);
150 CHECK(bss->rets_close[i] != strlen(bss->paths_stat[i]) + 1,
151 "check",
152 "failed to match stat return [%d]: %d vs %zd [%s]\n",
153 i, bss->rets_close[i], strlen(bss->paths_close[i]) + 1,
154 bss->paths_stat[i]);
155 }
156
157 cleanup:
158 test_d_path__destroy(skel);
159 }
160
test_d_path_check_rdonly_mem(void)161 static void test_d_path_check_rdonly_mem(void)
162 {
163 struct test_d_path_check_rdonly_mem *skel;
164
165 skel = test_d_path_check_rdonly_mem__open_and_load();
166 CHECK(skel, "skel_open", "unexpected_load_overwriting_rdonly_mem");
167
168 test_d_path_check_rdonly_mem__destroy(skel);
169 }
170
test_d_path_check_types(void)171 static void test_d_path_check_types(void)
172 {
173 struct test_d_path_check_types *skel;
174
175 skel = test_d_path_check_types__open_and_load();
176 CHECK(skel, "skel_open", "unexpected_load_passing_wrong_type");
177
178 test_d_path_check_types__destroy(skel);
179 }
180
test_d_path(void)181 void test_d_path(void)
182 {
183 if (test__start_subtest("basic"))
184 test_d_path_basic();
185
186 if (test__start_subtest("check_rdonly_mem"))
187 test_d_path_check_rdonly_mem();
188
189 if (test__start_subtest("check_alloc_mem"))
190 test_d_path_check_types();
191 }
192