xref: /aosp_15_r20/external/ltp/testcases/kernel/syscalls/fanotify/fanotify04.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2013 SUSE.  All Rights Reserved.
4  *
5  * Started by Jan Kara <[email protected]>
6  */
7 
8 /*\
9  * [Description]
10  * Check various fanotify special flags.
11  */
12 
13 #define _GNU_SOURCE
14 #include "config.h"
15 
16 #include <stdio.h>
17 #include <sys/stat.h>
18 #include <sys/types.h>
19 #include <errno.h>
20 #include <string.h>
21 #include <sys/syscall.h>
22 #include "tst_test.h"
23 
24 #ifdef HAVE_SYS_FANOTIFY_H
25 #include "fanotify.h"
26 
27 /* size of the event structure, not counting name */
28 #define EVENT_SIZE  (sizeof(struct fanotify_event_metadata))
29 
30 #define BUF_SIZE 256
31 #define TST_TOTAL 9
32 
33 static char fname[BUF_SIZE];
34 static char sname[BUF_SIZE];
35 static char dir[BUF_SIZE];
36 static int fd_notify;
37 static char event_buf[EVENT_SIZE];
38 
expect_str_fail(int expect)39 static char *expect_str_fail(int expect)
40 {
41 	if (expect == 0)
42 		return "failed";
43 	return "unexpectedly succeeded";
44 }
45 
expect_str_pass(int expect)46 static char *expect_str_pass(int expect)
47 {
48 	if (expect == 0)
49 		return "succeeded";
50 	return "failed";
51 }
52 
check_mark(char * file,unsigned long long flag,char * flagstr,int expect,void (* test_event)(char *))53 static void check_mark(char *file, unsigned long long flag, char *flagstr,
54 		       int expect, void (*test_event)(char *))
55 {
56 	if (fanotify_mark(fd_notify, FAN_MARK_ADD | flag, FAN_OPEN, AT_FDCWD,
57 			  file) != expect) {
58 		tst_res(TFAIL,
59 			"fanotify_mark (%d, FAN_MARK_ADD | %s, FAN_OPEN, "
60 			"AT_FDCWD, '%s') %s", fd_notify, flagstr, file,
61 			expect_str_fail(expect));
62 	} else {
63 		tst_res(TPASS,
64 			"fanotify_mark (%d, FAN_MARK_ADD | %s, FAN_OPEN, "
65 			"AT_FDCWD, '%s') %s", fd_notify, flagstr, file,
66 			expect_str_pass(expect));
67 
68 		/* If we expected failure there's nothing to clean up */
69 		if (expect == -1)
70 			return;
71 
72 		if (test_event)
73 			test_event(file);
74 
75 		SAFE_FANOTIFY_MARK(fd_notify, FAN_MARK_REMOVE | flag,
76 				  FAN_OPEN, AT_FDCWD, file);
77 	}
78 }
79 
80 #define CHECK_MARK(file, flag, expect, func) check_mark(file, flag, #flag, expect, func)
81 
do_open(char * file,int flag)82 static void do_open(char *file, int flag)
83 {
84 	int fd;
85 
86 	fd = SAFE_OPEN(file, O_RDONLY | flag);
87 	SAFE_CLOSE(fd);
88 }
89 
open_file(char * file)90 static void open_file(char *file)
91 {
92 	do_open(file, 0);
93 }
94 
open_dir(char * file)95 static void open_dir(char *file)
96 {
97 	do_open(file, O_DIRECTORY);
98 }
99 
verify_event(int mask)100 static void verify_event(int mask)
101 {
102 	struct fanotify_event_metadata *event;
103 	struct stat st;
104 
105 	/* Read the event */
106 	SAFE_READ(0, fd_notify, event_buf, EVENT_SIZE);
107 	event = (struct fanotify_event_metadata *)&event_buf;
108 	if (event->mask != FAN_OPEN) {
109 		tst_res(TFAIL, "got unexpected event %llx",
110 			(unsigned long long)event->mask);
111 	} else if (fstat(event->fd, &st) < 0) {
112 		tst_res(TFAIL, "failed to stat event->fd (%s)",
113 			strerror(errno));
114 	} else if ((int)(st.st_mode & S_IFMT) != mask) {
115 		tst_res(TFAIL, "event->fd points to object of different type "
116 			"(%o != %o)", st.st_mode & S_IFMT, mask);
117 	} else {
118 		tst_res(TPASS, "event generated properly for type %o", mask);
119 	}
120 	if (event->fd != FAN_NOFD)
121 		SAFE_CLOSE(event->fd);
122 }
123 
do_open_test(char * file,int flag,int mask)124 static void do_open_test(char *file, int flag, int mask)
125 {
126 	do_open(file, flag);
127 
128 	verify_event(mask);
129 }
130 
test_open_file(char * file)131 static void test_open_file(char *file)
132 {
133 	do_open_test(file, 0, S_IFREG);
134 }
135 
verify_no_event(void)136 static void verify_no_event(void)
137 {
138 	int ret;
139 
140 	ret = read(fd_notify, event_buf, EVENT_SIZE);
141 	if (ret != -1) {
142 		struct fanotify_event_metadata *event;
143 
144 		event = (struct fanotify_event_metadata *)&event_buf;
145 		tst_res(TFAIL, "seen unexpected event (mask %llx)",
146 			(unsigned long long)event->mask);
147 		/* Cleanup fd from the event */
148 		if (event->fd != FAN_NOFD)
149 			SAFE_CLOSE(event->fd);
150 	} else if (errno != EAGAIN) {
151 		tst_res(TFAIL | TERRNO, "read(%d, buf, %zu) failed", fd_notify,
152 			EVENT_SIZE);
153 	} else {
154 		tst_res(TPASS, "No event as expected");
155 	}
156 }
157 
test_open_symlink(char * file)158 static void test_open_symlink(char *file)
159 {
160 	/* Since mark is on a symlink, no event should be generated by opening a file */
161 	do_open(file, 0);
162 	verify_no_event();
163 }
164 
test01(void)165 static void test01(void)
166 {
167 	/* Check ONLYDIR on a directory */
168 	CHECK_MARK(".", FAN_MARK_ONLYDIR, 0, NULL);
169 
170 	/* Check ONLYDIR without a directory */
171 	CHECK_MARK(fname, FAN_MARK_ONLYDIR, -1, NULL);
172 
173 	/* Check DONT_FOLLOW for a symlink */
174 	CHECK_MARK(sname, FAN_MARK_DONT_FOLLOW, 0, test_open_symlink);
175 
176 	/* Check without DONT_FOLLOW for a symlink */
177 	CHECK_MARK(sname, 0, 0, test_open_file);
178 
179 	/* Verify FAN_MARK_FLUSH destroys all inode marks */
180 	SAFE_FANOTIFY_MARK(fd_notify, FAN_MARK_ADD, FAN_OPEN, AT_FDCWD, fname);
181 	SAFE_FANOTIFY_MARK(fd_notify, FAN_MARK_ADD, FAN_OPEN | FAN_ONDIR,
182 			   AT_FDCWD, dir);
183 	open_file(fname);
184 	verify_event(S_IFREG);
185 	open_dir(dir);
186 	verify_event(S_IFDIR);
187 	SAFE_FANOTIFY_MARK(fd_notify, FAN_MARK_FLUSH, 0, AT_FDCWD, ".");
188 
189 	open_dir(dir);
190 	verify_no_event();
191 }
192 
setup(void)193 static void setup(void)
194 {
195 	int fd;
196 
197 	sprintf(fname, "fname_%d", getpid());
198 	fd = SAFE_OPEN(fname, O_RDWR | O_CREAT, 0644);
199 	SAFE_CLOSE(fd);
200 
201 	sprintf(sname, "symlink_%d", getpid());
202 	SAFE_SYMLINK(fname, sname);
203 
204 	sprintf(dir, "dir_%d", getpid());
205 	SAFE_MKDIR(dir, 0755);
206 
207 	fd_notify = SAFE_FANOTIFY_INIT(FAN_CLASS_NOTIF | FAN_NONBLOCK,
208 					O_RDONLY);
209 }
210 
cleanup(void)211 static void cleanup(void)
212 {
213 	if (fd_notify > 0)
214 		SAFE_CLOSE(fd_notify);
215 }
216 
217 static struct tst_test test = {
218 	.test_all = test01,
219 	.setup = setup,
220 	.cleanup = cleanup,
221 	.needs_tmpdir = 1,
222 	.needs_root = 1
223 };
224 
225 #else
226 	TST_TEST_TCONF("system doesn't have required fanotify support");
227 #endif
228