1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) 2014 SUSE. All Rights Reserved.
4 *
5 * Started by Jan Kara <[email protected]>
6 */
7
8 /*\
9 * [Description]
10 * Check that fanotify properly merges ignore mask of an inode and mountpoint.
11 */
12
13 /*
14 * This is a regression test for:
15 *
16 * commit 8edc6e1688fc8f02c8c1f53a2ec4928cb1055f4d
17 * Author: Jan Kara <[email protected]>
18 * Date: Thu Nov 13 15:19:33 2014 -0800
19 *
20 * fanotify: fix notification of groups with inode & mount marks
21 *
22 * The overlayfs test case is a regression test for:
23 *
24 * commit d989903058a83e8536cc7aadf9256a47d5c173fe
25 * Author: Amir Goldstein <[email protected]>
26 * Date: Wed Apr 24 19:39:50 2019 +0300
27 *
28 * ovl: do not generate duplicate fsnotify events for "fake" path
29 */
30
31 #define _GNU_SOURCE
32 #include "config.h"
33
34 #include <stdio.h>
35 #include <sys/stat.h>
36 #include <sys/types.h>
37 #include <errno.h>
38 #include <string.h>
39 #include <sys/mount.h>
40 #include <sys/syscall.h>
41 #include "tst_test.h"
42
43 #ifdef HAVE_SYS_FANOTIFY_H
44 #include "fanotify.h"
45
46 #define EVENT_MAX 1024
47 /* size of the event structure, not counting name */
48 #define EVENT_SIZE (sizeof(struct fanotify_event_metadata))
49 /* reasonable guess as to size of 1024 events */
50 #define EVENT_BUF_LEN (EVENT_MAX * EVENT_SIZE)
51
52 static unsigned int fanotify_prio[] = {
53 FAN_CLASS_PRE_CONTENT,
54 FAN_CLASS_CONTENT,
55 FAN_CLASS_NOTIF
56 };
57 #define FANOTIFY_PRIORITIES ARRAY_SIZE(fanotify_prio)
58
59 #define GROUPS_PER_PRIO 3
60
61 #define BUF_SIZE 256
62 static char fname[BUF_SIZE];
63 static int fd_notify[FANOTIFY_PRIORITIES][GROUPS_PER_PRIO];
64
65 static char event_buf[EVENT_BUF_LEN];
66
67 static const char mntpoint[] = OVL_BASE_MNTPOINT;
68
69 static int ovl_mounted;
70
71 static struct tcase {
72 const char *tname;
73 const char *mnt;
74 int use_overlay;
75 } tcases[] = {
76 { "Fanotify merge mount mark", mntpoint, 0 },
77 { "Fanotify merge overlayfs mount mark", OVL_MNT, 1 },
78 };
79
create_fanotify_groups(void)80 static void create_fanotify_groups(void)
81 {
82 unsigned int p, i;
83
84 for (p = 0; p < FANOTIFY_PRIORITIES; p++) {
85 for (i = 0; i < GROUPS_PER_PRIO; i++) {
86 fd_notify[p][i] = SAFE_FANOTIFY_INIT(fanotify_prio[p] |
87 FAN_NONBLOCK,
88 O_RDONLY);
89
90 /* Add mount mark for each group */
91 SAFE_FANOTIFY_MARK(fd_notify[p][i],
92 FAN_MARK_ADD | FAN_MARK_MOUNT,
93 FAN_MODIFY,
94 AT_FDCWD, fname);
95
96 /* Add ignore mark for groups with higher priority */
97 if (p == 0)
98 continue;
99
100 SAFE_FANOTIFY_MARK(fd_notify[p][i],
101 FAN_MARK_ADD |
102 FAN_MARK_IGNORED_MASK |
103 FAN_MARK_IGNORED_SURV_MODIFY,
104 FAN_MODIFY, AT_FDCWD, fname);
105 }
106 }
107 }
108
cleanup_fanotify_groups(void)109 static void cleanup_fanotify_groups(void)
110 {
111 unsigned int i, p;
112
113 for (p = 0; p < FANOTIFY_PRIORITIES; p++) {
114 for (i = 0; i < GROUPS_PER_PRIO; i++) {
115 if (fd_notify[p][i] > 0)
116 SAFE_CLOSE(fd_notify[p][i]);
117 }
118 }
119 }
120
verify_event(int group,struct fanotify_event_metadata * event)121 static void verify_event(int group, struct fanotify_event_metadata *event)
122 {
123 if (event->mask != FAN_MODIFY) {
124 tst_res(TFAIL, "group %d got event: mask %llx (expected %llx) "
125 "pid=%u fd=%d", group, (unsigned long long)event->mask,
126 (unsigned long long)FAN_MODIFY,
127 (unsigned int)event->pid, event->fd);
128 } else if (event->pid != getpid()) {
129 tst_res(TFAIL, "group %d got event: mask %llx pid=%u "
130 "(expected %u) fd=%d", group,
131 (unsigned long long)event->mask, (unsigned int)event->pid,
132 (unsigned int)getpid(), event->fd);
133 } else {
134 tst_res(TPASS, "group %d got event: mask %llx pid=%u fd=%d",
135 group, (unsigned long long)event->mask,
136 (unsigned int)event->pid, event->fd);
137 }
138 }
139
140 /* Close all file descriptors of read events */
close_events_fd(struct fanotify_event_metadata * event,int buflen)141 static void close_events_fd(struct fanotify_event_metadata *event, int buflen)
142 {
143 while (buflen >= (int)FAN_EVENT_METADATA_LEN) {
144 if (event->fd != FAN_NOFD)
145 SAFE_CLOSE(event->fd);
146 buflen -= (int)FAN_EVENT_METADATA_LEN;
147 event++;
148 }
149 }
150
test_fanotify(unsigned int n)151 static void test_fanotify(unsigned int n)
152 {
153 int ret;
154 unsigned int p, i;
155 struct fanotify_event_metadata *event;
156 struct tcase *tc = &tcases[n];
157
158 tst_res(TINFO, "Test #%d: %s", n, tc->tname);
159
160 if (tc->use_overlay && !ovl_mounted) {
161 tst_res(TCONF, "overlayfs is not configured in this kernel");
162 return;
163 }
164
165 sprintf(fname, "%s/tfile_%d", tc->mnt, getpid());
166 SAFE_TOUCH(fname, 0644, NULL);
167
168 create_fanotify_groups();
169
170 /*
171 * generate sequence of events
172 */
173 SAFE_FILE_PRINTF(fname, "1");
174
175 /* First verify all groups without ignore mask got the event */
176 for (i = 0; i < GROUPS_PER_PRIO; i++) {
177 ret = read(fd_notify[0][i], event_buf, EVENT_BUF_LEN);
178 if (ret < 0) {
179 if (errno == EAGAIN) {
180 tst_res(TFAIL, "group %d did not get "
181 "event", i);
182 }
183 tst_brk(TBROK | TERRNO,
184 "reading fanotify events failed");
185 }
186 if (ret < (int)FAN_EVENT_METADATA_LEN) {
187 tst_brk(TBROK,
188 "short read when reading fanotify "
189 "events (%d < %d)", ret,
190 (int)EVENT_BUF_LEN);
191 }
192 event = (struct fanotify_event_metadata *)event_buf;
193 if (ret > (int)event->event_len) {
194 tst_res(TFAIL, "group %d got more than one "
195 "event (%d > %d)", i, ret,
196 event->event_len);
197 } else {
198 verify_event(i, event);
199 }
200 close_events_fd(event, ret);
201 }
202
203 for (p = 1; p < FANOTIFY_PRIORITIES; p++) {
204 for (i = 0; i < GROUPS_PER_PRIO; i++) {
205 ret = read(fd_notify[p][i], event_buf, EVENT_BUF_LEN);
206 if (ret > 0) {
207 tst_res(TFAIL, "group %d got event",
208 p*GROUPS_PER_PRIO + i);
209 close_events_fd((void *)event_buf, ret);
210 } else if (ret == 0) {
211 tst_brk(TBROK, "zero length "
212 "read from fanotify fd");
213 } else if (errno != EAGAIN) {
214 tst_brk(TBROK | TERRNO,
215 "reading fanotify events failed");
216 } else {
217 tst_res(TPASS, "group %d got no event",
218 p*GROUPS_PER_PRIO + i);
219 }
220 }
221 }
222 cleanup_fanotify_groups();
223 }
224
setup(void)225 static void setup(void)
226 {
227 ovl_mounted = TST_MOUNT_OVERLAY();
228 }
229
cleanup(void)230 static void cleanup(void)
231 {
232 cleanup_fanotify_groups();
233
234 if (ovl_mounted)
235 SAFE_UMOUNT(OVL_MNT);
236 }
237
238 static struct tst_test test = {
239 .test = test_fanotify,
240 .tcnt = ARRAY_SIZE(tcases),
241 .setup = setup,
242 .cleanup = cleanup,
243 .needs_root = 1,
244 .mount_device = 1,
245 .mntpoint = mntpoint,
246 .tags = (const struct tst_tag[]) {
247 {"linux-git", "8edc6e1688fc"},
248 {"linux-git", "d989903058a8"},
249 {}
250 }
251 };
252
253 #else
254 TST_TEST_TCONF("system doesn't have required fanotify support");
255 #endif
256