1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2014 SUSE. All Rights Reserved.
4 *
5 * Started by Jan Kara <jack@suse.cz>
6 *
7 * DESCRIPTION
8 * Check that fanotify properly merges ignore mask of an inode and
9 * mountpoint.
10 *
11 * This is a regression test for:
12 *
13 * commit 8edc6e1688fc8f02c8c1f53a2ec4928cb1055f4d
14 * Author: Jan Kara <jack@suse.cz>
15 * Date: Thu Nov 13 15:19:33 2014 -0800
16 *
17 * fanotify: fix notification of groups with inode & mount marks
18 *
19 * The overlayfs test case is a regression test for:
20 *
21 * commit d989903058a83e8536cc7aadf9256a47d5c173fe
22 * Author: Amir Goldstein <amir73il@gmail.com>
23 * Date: Wed Apr 24 19:39:50 2019 +0300
24 *
25 * ovl: do not generate duplicate fsnotify events for "fake" path
26 */
27 #define _GNU_SOURCE
28 #include "config.h"
29
30 #include <stdio.h>
31 #include <sys/stat.h>
32 #include <sys/types.h>
33 #include <fcntl.h>
34 #include <errno.h>
35 #include <string.h>
36 #include <sys/mount.h>
37 #include <sys/syscall.h>
38 #include "tst_test.h"
39 #include "fanotify.h"
40
41 #if defined(HAVE_SYS_FANOTIFY_H)
42 #include <sys/fanotify.h>
43
44 #define EVENT_MAX 1024
45 /* size of the event structure, not counting name */
46 #define EVENT_SIZE (sizeof (struct fanotify_event_metadata))
47 /* reasonable guess as to size of 1024 events */
48 #define EVENT_BUF_LEN (EVENT_MAX * EVENT_SIZE)
49
50 unsigned int fanotify_prio[] = {
51 FAN_CLASS_PRE_CONTENT,
52 FAN_CLASS_CONTENT,
53 FAN_CLASS_NOTIF
54 };
55 #define FANOTIFY_PRIORITIES ARRAY_SIZE(fanotify_prio)
56
57 #define GROUPS_PER_PRIO 3
58
59 #define BUF_SIZE 256
60 static char fname[BUF_SIZE];
61 static int fd_notify[FANOTIFY_PRIORITIES][GROUPS_PER_PRIO];
62
63 static char event_buf[EVENT_BUF_LEN];
64
65 static const char mntpoint[] = OVL_BASE_MNTPOINT;
66
67 static int ovl_mounted;
68
69 static struct tcase {
70 const char *tname;
71 const char *mnt;
72 int use_overlay;
73 } tcases[] = {
74 { "Fanotify merge mount mark", mntpoint, 0 },
75 { "Fanotify merge overlayfs mount mark", OVL_MNT, 1 },
76 };
77
create_fanotify_groups(void)78 static void create_fanotify_groups(void)
79 {
80 unsigned int p, i;
81 int ret;
82
83 for (p = 0; p < FANOTIFY_PRIORITIES; p++) {
84 for (i = 0; i < GROUPS_PER_PRIO; i++) {
85 fd_notify[p][i] = SAFE_FANOTIFY_INIT(fanotify_prio[p] |
86 FAN_NONBLOCK,
87 O_RDONLY);
88
89 /* Add mount mark for each group */
90 ret = fanotify_mark(fd_notify[p][i],
91 FAN_MARK_ADD | FAN_MARK_MOUNT,
92 FAN_MODIFY,
93 AT_FDCWD, fname);
94 if (ret < 0) {
95 tst_brk(TBROK | TERRNO,
96 "fanotify_mark(%d, FAN_MARK_ADD | "
97 "FAN_MARK_MOUNT, FAN_MODIFY, AT_FDCWD,"
98 " %s) failed", fd_notify[p][i], fname);
99 }
100 /* Add ignore mark for groups with higher priority */
101 if (p == 0)
102 continue;
103 ret = fanotify_mark(fd_notify[p][i],
104 FAN_MARK_ADD |
105 FAN_MARK_IGNORED_MASK |
106 FAN_MARK_IGNORED_SURV_MODIFY,
107 FAN_MODIFY, AT_FDCWD, fname);
108 if (ret < 0) {
109 tst_brk(TBROK | TERRNO,
110 "fanotify_mark(%d, FAN_MARK_ADD | "
111 "FAN_MARK_IGNORED_MASK | "
112 "FAN_MARK_IGNORED_SURV_MODIFY, "
113 "FAN_MODIFY, AT_FDCWD, %s) failed",
114 fd_notify[p][i], fname);
115 }
116 }
117 }
118 }
119
cleanup_fanotify_groups(void)120 static void cleanup_fanotify_groups(void)
121 {
122 unsigned int i, p;
123
124 for (p = 0; p < FANOTIFY_PRIORITIES; p++) {
125 for (i = 0; i < GROUPS_PER_PRIO; i++) {
126 if (fd_notify[p][i] > 0)
127 SAFE_CLOSE(fd_notify[p][i]);
128 }
129 }
130 }
131
verify_event(int group,struct fanotify_event_metadata * event)132 static void verify_event(int group, struct fanotify_event_metadata *event)
133 {
134 if (event->mask != FAN_MODIFY) {
135 tst_res(TFAIL, "group %d got event: mask %llx (expected %llx) "
136 "pid=%u fd=%d", group, (unsigned long long)event->mask,
137 (unsigned long long)FAN_MODIFY,
138 (unsigned)event->pid, event->fd);
139 } else if (event->pid != getpid()) {
140 tst_res(TFAIL, "group %d got event: mask %llx pid=%u "
141 "(expected %u) fd=%d", group,
142 (unsigned long long)event->mask, (unsigned)event->pid,
143 (unsigned)getpid(), event->fd);
144 } else {
145 tst_res(TPASS, "group %d got event: mask %llx pid=%u fd=%d",
146 group, (unsigned long long)event->mask,
147 (unsigned)event->pid, event->fd);
148 }
149 }
150
151 /* Close all file descriptors of read events */
close_events_fd(struct fanotify_event_metadata * event,int buflen)152 static void close_events_fd(struct fanotify_event_metadata *event, int buflen)
153 {
154 while (buflen >= (int)FAN_EVENT_METADATA_LEN) {
155 if (event->fd != FAN_NOFD)
156 SAFE_CLOSE(event->fd);
157 buflen -= (int)FAN_EVENT_METADATA_LEN;
158 event++;
159 }
160 }
161
test_fanotify(unsigned int n)162 void test_fanotify(unsigned int n)
163 {
164 int ret;
165 unsigned int p, i;
166 struct fanotify_event_metadata *event;
167 struct tcase *tc = &tcases[n];
168
169 tst_res(TINFO, "Test #%d: %s", n, tc->tname);
170
171 if (tc->use_overlay && !ovl_mounted) {
172 tst_res(TCONF,
173 "overlayfs is not configured in this kernel.");
174 return;
175 }
176
177 sprintf(fname, "%s/tfile_%d", tc->mnt, getpid());
178 SAFE_TOUCH(fname, 0644, NULL);
179
180 create_fanotify_groups();
181
182 /*
183 * generate sequence of events
184 */
185 SAFE_FILE_PRINTF(fname, "1");
186
187 /* First verify all groups without ignore mask got the event */
188 for (i = 0; i < GROUPS_PER_PRIO; i++) {
189 ret = read(fd_notify[0][i], event_buf, EVENT_BUF_LEN);
190 if (ret < 0) {
191 if (errno == EAGAIN) {
192 tst_res(TFAIL, "group %d did not get "
193 "event", i);
194 }
195 tst_brk(TBROK | TERRNO,
196 "reading fanotify events failed");
197 }
198 if (ret < (int)FAN_EVENT_METADATA_LEN) {
199 tst_brk(TBROK,
200 "short read when reading fanotify "
201 "events (%d < %d)", ret,
202 (int)EVENT_BUF_LEN);
203 }
204 event = (struct fanotify_event_metadata *)event_buf;
205 if (ret > (int)event->event_len) {
206 tst_res(TFAIL, "group %d got more than one "
207 "event (%d > %d)", i, ret,
208 event->event_len);
209 } else {
210 verify_event(i, event);
211 }
212 close_events_fd(event, ret);
213 }
214
215 for (p = 1; p < FANOTIFY_PRIORITIES; p++) {
216 for (i = 0; i < GROUPS_PER_PRIO; i++) {
217 ret = read(fd_notify[p][i], event_buf, EVENT_BUF_LEN);
218 if (ret > 0) {
219 tst_res(TFAIL, "group %d got event",
220 p*GROUPS_PER_PRIO + i);
221 close_events_fd((void *)event_buf, ret);
222 } else if (ret == 0) {
223 tst_brk(TBROK, "zero length "
224 "read from fanotify fd");
225 } else if (errno != EAGAIN) {
226 tst_brk(TBROK | TERRNO,
227 "reading fanotify events failed");
228 } else {
229 tst_res(TPASS, "group %d got no event",
230 p*GROUPS_PER_PRIO + i);
231 }
232 }
233 }
234 cleanup_fanotify_groups();
235 }
236
setup(void)237 static void setup(void)
238 {
239 ovl_mounted = TST_MOUNT_OVERLAY();
240 }
241
cleanup(void)242 static void cleanup(void)
243 {
244 cleanup_fanotify_groups();
245
246 if (ovl_mounted)
247 SAFE_UMOUNT(OVL_MNT);
248 }
249
250 static struct tst_test test = {
251 .test = test_fanotify,
252 .tcnt = ARRAY_SIZE(tcases),
253 .setup = setup,
254 .cleanup = cleanup,
255 .needs_root = 1,
256 .mount_device = 1,
257 .mntpoint = mntpoint,
258 .tags = (const struct tst_tag[]) {
259 {"linux-git", "8edc6e1688fc"},
260 {"linux-git", "d989903058a8"},
261 {}
262 }
263 };
264
265 #else
266 TST_TEST_TCONF("system doesn't have required fanotify support");
267 #endif
268