syscalls/fanotify: Verify that inode ignore masks are properly reflected

Verify that when inode has an ignore mask set, it is properly reflected
when notifying a mountpoint. The test verifies fix "fanotify: Fix notification
of groups with inode & mount marks" in the Linux kernel.

Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/testcases/kernel/syscalls/fanotify/fanotify06.c b/testcases/kernel/syscalls/fanotify/fanotify06.c
new file mode 100644
index 0000000..8dcd68a
--- /dev/null
+++ b/testcases/kernel/syscalls/fanotify/fanotify06.c
@@ -0,0 +1,267 @@
+/*
+ * Copyright (c) 2014 SUSE.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like.  Any license provided herein, whether implied or
+ * otherwise, applies only to this software file.  Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Started by Jan Kara <jack@suse.cz>
+ *
+ * DESCRIPTION
+ *     Check that fanotify properly merges ignore mask of an inode and
+ *     mountpoint.
+ */
+#include "config.h"
+
+#include <stdio.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/syscall.h>
+#include "test.h"
+#include "usctest.h"
+#include "linux_syscall_numbers.h"
+#include "fanotify.h"
+#include "safe_macros.h"
+
+char *TCID = "fanotify06";
+
+#if defined(HAVE_SYS_FANOTIFY_H)
+#include <sys/fanotify.h>
+
+#define EVENT_MAX 1024
+/* size of the event structure, not counting name */
+#define EVENT_SIZE  (sizeof (struct fanotify_event_metadata))
+/* reasonable guess as to size of 1024 events */
+#define EVENT_BUF_LEN        (EVENT_MAX * EVENT_SIZE)
+
+static void setup(void);
+static void cleanup(void);
+
+unsigned int fanotify_prio[] = {
+	FAN_CLASS_PRE_CONTENT,
+	FAN_CLASS_CONTENT,
+	FAN_CLASS_NOTIF
+};
+#define FANOTIFY_PRIORITIES ARRAY_SIZE(fanotify_prio)
+
+#define GROUPS_PER_PRIO 3
+
+int TST_TOTAL = GROUPS_PER_PRIO * FANOTIFY_PRIORITIES;
+
+#define BUF_SIZE 256
+static char fname[BUF_SIZE];
+static int fd;
+static int fd_notify[FANOTIFY_PRIORITIES][GROUPS_PER_PRIO];
+
+static char event_buf[EVENT_BUF_LEN];
+
+static void create_fanotify_groups(void)
+{
+	unsigned int p, i;
+	int ret;
+
+	for (p = 0; p < FANOTIFY_PRIORITIES; p++) {
+		for (i = 0; i < GROUPS_PER_PRIO; i++) {
+			fd_notify[p][i] = fanotify_init(fanotify_prio[p] |
+							FAN_NONBLOCK,
+							O_RDONLY);
+			if (fd_notify[p][i] < 0) {
+				if (errno == ENOSYS) {
+					tst_brkm(TCONF, cleanup,
+						 "fanotify is not configured in"
+						 " this kernel.");
+				} else {
+					tst_brkm(TBROK | TERRNO, cleanup,
+						 "fanotify_init failed");
+				}
+			}
+			/* Add mount mark for each group */
+			ret = fanotify_mark(fd_notify[p][i],
+					    FAN_MARK_ADD | FAN_MARK_MOUNT,
+					    FAN_MODIFY,
+					    AT_FDCWD, ".");
+			if (ret < 0) {
+				tst_brkm(TBROK | TERRNO, cleanup,
+					 "fanotify_mark(%d, FAN_MARK_ADD | "
+					 "FAN_MARK_MOUNT, FAN_MODIFY, AT_FDCWD,"
+					 " '.') failed", fd_notify[p][i]);
+			}
+			/* Add ignore mark for groups with higher priority */
+			if (p == 0)
+				continue;
+			ret = fanotify_mark(fd_notify[p][i],
+					    FAN_MARK_ADD |
+					    FAN_MARK_IGNORED_MASK |
+					    FAN_MARK_IGNORED_SURV_MODIFY,
+					    FAN_MODIFY, AT_FDCWD, fname);
+			if (ret < 0) {
+				tst_brkm(TBROK | TERRNO, cleanup,
+					 "fanotify_mark(%d, FAN_MARK_ADD | "
+					 "FAN_MARK_IGNORED_MASK | "
+					 "FAN_MARK_IGNORED_SURV_MODIFY, "
+					 "FAN_MODIFY, AT_FDCWD, %s) failed",
+					 fd_notify[p][i], fname);
+			}
+		}
+	}
+}
+
+static void cleanup_fanotify_groups(void)
+{
+	unsigned int i, p;
+
+	for (p = 0; p < FANOTIFY_PRIORITIES; p++) {
+		for (i = 0; i < GROUPS_PER_PRIO; i++) {
+			if (fd_notify[p][i] && fd_notify[p][i] != -1) {
+				if (close(fd_notify[p][i]) == -1)
+					tst_resm(TWARN, "close(%d) failed",
+						 fd_notify[p][i]);
+				fd_notify[p][i] = 0;
+			}
+		}
+	}
+}
+
+static void verify_event(int group, struct fanotify_event_metadata *event)
+{
+	if (event->mask != FAN_MODIFY) {
+		tst_resm(TFAIL, "group %d get event: mask %llx (expected %llx) "
+			 "pid=%u fd=%u", group, (unsigned long long)event->mask,
+			 (unsigned long long)FAN_MODIFY,
+			 (unsigned)event->pid, event->fd);
+	} else if (event->pid != getpid()) {
+		tst_resm(TFAIL, "group %d get event: mask %llx pid=%u "
+			 "(expected %u) fd=%u", group,
+			 (unsigned long long)event->mask, (unsigned)event->pid,
+			 (unsigned)getpid(), event->fd);
+	} else {
+		tst_resm(TPASS, "group %d get event: mask %llx pid=%u fd=%u",
+			 group, (unsigned long long)event->mask,
+			 (unsigned)event->pid, event->fd);
+	}
+}
+
+int main(int ac, char **av)
+{
+	int lc;
+	const char *msg;
+
+	if ((msg = parse_opts(ac, av, NULL, NULL)) != NULL)
+		tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg);
+
+	setup();
+
+	for (lc = 0; TEST_LOOPING(lc); lc++) {
+		int ret;
+		unsigned int p, i;
+		struct fanotify_event_metadata *event;
+
+		create_fanotify_groups();
+
+		/*
+		 * generate sequence of events
+		 */
+		fd = SAFE_OPEN(cleanup, fname, O_RDWR);
+		SAFE_WRITE(cleanup, 1, fd, fname, strlen(fname));
+		SAFE_CLOSE(cleanup, fd);
+
+		/* First verify all groups without ignore mask got the event */
+		for (i = 0; i < GROUPS_PER_PRIO; i++) {
+			ret = read(fd_notify[0][i], event_buf, EVENT_BUF_LEN);
+			if (ret < 0) {
+				if (errno == EAGAIN) {
+					tst_resm(TFAIL, "group %d did not get "
+						 "event", i);
+				}
+				tst_brkm(TBROK | TERRNO, cleanup,
+					 "reading fanotify events failed");
+			}
+			if (ret < (int)FAN_EVENT_METADATA_LEN) {
+				tst_brkm(TBROK, cleanup,
+					 "short read when reading fanotify "
+					 "events (%d < %d)", ret,
+					 (int)EVENT_BUF_LEN);
+			}
+			event = (struct fanotify_event_metadata *)event_buf;
+			if (ret > (int)event->event_len) {
+				tst_resm(TFAIL, "group %d got more than one "
+					 "event (%d > %d)", i, ret,
+					 event->event_len);
+			} else
+				verify_event(i, event);
+			close(event->fd);
+		}
+		for (p = 1; p < FANOTIFY_PRIORITIES; p++) {
+			for (i = 0; i < GROUPS_PER_PRIO; i++) {
+				ret = read(fd_notify[p][i], event_buf, EVENT_BUF_LEN);
+				if (ret > 0) {
+					tst_resm(TFAIL, "group %d got event",
+						 p*GROUPS_PER_PRIO + i);
+				} else if (ret == 0) {
+					tst_brkm(TBROK, cleanup, "zero length "
+						 "read from fanotify fd");
+				} else if (errno != EAGAIN) {
+					tst_brkm(TBROK | TERRNO, cleanup,
+						 "reading fanotify events failed");
+				} else {
+					tst_resm(TPASS, "group %d got no event",
+						 p*GROUPS_PER_PRIO + i);
+				}
+			}
+		}
+		cleanup_fanotify_groups();
+	}
+
+	cleanup();
+	tst_exit();
+}
+
+static void setup(void)
+{
+	tst_sig(NOFORK, DEF_HANDLER, cleanup);
+
+	TEST_PAUSE;
+
+	tst_tmpdir();
+
+	sprintf(fname, "tfile_%d", getpid());
+	fd = SAFE_OPEN(cleanup, fname, O_RDWR | O_CREAT, 0700);
+	SAFE_WRITE(cleanup, 1, fd, fname, 1);
+
+	/* close the file we have open */
+	SAFE_CLOSE(cleanup, fd);
+}
+
+static void cleanup(void)
+{
+	cleanup_fanotify_groups();
+	TEST_CLEANUP;
+	tst_rmdir();
+}
+
+#else
+
+int main(void)
+{
+	tst_brkm(TCONF, NULL, "system doesn't have required fanotify support");
+}
+
+#endif