syscalls/ipc: msgctl06: Add a test for MSG_STAT_ANY

Validate the content of the msginfo structure and the return value.

The return value is highest used index to a kernel table, so we call
msgctl() with MSG_STAT_ANY which shouldn't fail if the value is correct.

We also parse /proc/sysvipc/msg and check that the information is
consistent with the content of msginfo structure.

It refers to shmctl04.

Signed-off-by: Feiyu Zhu <zhufy.jy@cn.fujitsu.com>
Reviewed-by: Cyril Hrubis <chrubis@suse.cz>

runtest/syscalls

@@ -800,6 +800,7 @@ msgctl02 msgctl02
 msgctl03 msgctl03
 msgctl04 msgctl04
 msgctl05 msgctl05
+msgctl06 msgctl06
 msgstress01 msgstress01
 msgstress02 msgstress02
 msgstress03 msgstress03

runtest/syscalls-ipc

@@ -3,6 +3,7 @@ msgctl02 msgctl02
 msgctl03 msgctl03
 msgctl04 msgctl04
 msgctl05 msgctl05
+msgctl06 msgctl06
 msgstress01 msgstress01
 msgstress02 msgstress02
 msgstress03 msgstress03

testcases/kernel/syscalls/ipc/msgctl/.gitignore

@@ -3,4 +3,5 @@
 /msgctl03
 /msgctl04
 /msgctl05
+/msgctl06
 /msgctl12

testcases/kernel/syscalls/ipc/msgctl/msgctl06.c

@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2020 FUJITSU LIMITED. All rights reserved.
+ * Author: Feiyu Zhu <zhufy.jy@cn.fujitsu.com>
+ */
+/*\
+ * [DESCRIPTION]
+ *
+ * Call msgctl() with MSG_INFO flag and check that:
+ *
+ * * The returned index points to a valid MSG by calling MSG_STAT_ANY
+ * * Also count that valid indexes < returned max index sums up to used_ids
+ * * And the data are consistent with /proc/sysvipc/msg
+ *
+ * There is a possible race between the call to the msgctl() and read from the
+ * proc file so this test cannot be run in parallel with any IPC testcases that
+ * adds or removes MSG queues.
+ *
+ * Note what we create a MSG segment in the test setup and send msg to make sure
+ * that there is at least one during the testrun.
+ *
+ * Also note that for MSG_INFO the members of the msginfo structure have
+ * completely different meaning than their names seems to suggest.
+\*/
+
+#include <stdio.h>
+#include <pwd.h>
+#include "tst_test.h"
+#include "tst_safe_sysv_ipc.h"
+#include "libnewipc.h"
+#include "lapi/msg.h"
+
+static int msg_id = -1;
+static struct passwd *ltpuser;
+static uid_t nobody_uid, root_uid;
+
+static struct tcases {
+	uid_t *uid;
+	char *desc;
+} tests[] = {
+	{&nobody_uid, "with nobody user"},
+	{&root_uid, "with root user"}
+};
+
+static void parse_proc_sysvipc(struct msginfo *info)
+{
+	FILE *f = fopen("/proc/sysvipc/msg", "r");
+	int queue_cnt = 0;
+	int msg_cnt = 0;
+	int msg_bytes = 0;
+
+	/* Eat header */
+	for (;;) {
+		int c = fgetc(f);
+
+		if (c == '\n' || c == EOF)
+			break;
+	}
+
+	int cbytes, msgs;
+
+	/*
+	 * Sum queue and byte for all elements listed, which should equal
+	 * the data returned in the msginfo structure.
+	 */
+	while (fscanf(f, "%*i %*i %*i %i %i %*i %*i %*i %*i %*i %*i %*i %*i %*i",
+	              &cbytes, &msgs) > 0){
+		queue_cnt++;
+		msg_cnt += msgs;
+		msg_bytes += cbytes;
+	}
+
+	if (info->msgpool != queue_cnt) {
+		tst_res(TFAIL, "msgpool = %i, expected %i",
+			info->msgpool, queue_cnt);
+	} else {
+		tst_res(TPASS, "queue_cnt = %i", queue_cnt);
+	}
+
+	if (info->msgmap != msg_cnt) {
+		tst_res(TFAIL, "msgmap = %i, expected %i",
+			info->msgpool, msg_cnt);
+	} else {
+		tst_res(TPASS, "msg_cnt = %i", msg_cnt);
+	}
+
+	if (info->msgtql != msg_bytes) {
+		tst_res(TFAIL, "msgtql = %i, expected %i",
+			info->msgtql, msg_bytes);
+	} else {
+		tst_res(TPASS, "msg_bytes = %i", msg_bytes);
+	}
+
+	fclose(f);
+}
+
+static void verify_msgctl(unsigned int n)
+{
+	struct tcases *tc = &tests[n];
+	int i, msgid, cnt = 0;
+	struct msqid_ds buf;
+	struct msginfo info;
+
+	tst_res(TINFO, "Test MSG_STAT_ANY %s", tc->desc);
+
+	SAFE_SETEUID(*tc->uid);
+
+	TEST(msgctl(0, MSG_INFO, (struct msqid_ds *)&info));
+
+	if (TST_RET == -1) {
+		tst_res(TFAIL | TTERRNO, "msgctl(0, MSG_INFO, ...)");
+		return;
+	}
+
+	msgid = msgctl(TST_RET, MSG_STAT_ANY, &buf);
+
+	if (msgid == -1) {
+		tst_res(TFAIL | TTERRNO, "MSG_INFO haven't returned a valid index");
+	} else {
+		tst_res(TPASS, "MSG_INFO returned valid index %li to msgid %i",
+			TST_RET, msgid);
+	}
+
+	for (i = 0; i <= TST_RET; i++) {
+		if (msgctl(i, MSG_STAT_ANY, &buf) != -1)
+			cnt++;
+	}
+
+	if (cnt == info.msgpool) {
+		tst_res(TPASS, "Counted used = %i", cnt);
+	} else {
+		tst_res(TFAIL, "Counted used = %i, msgpool = %i",
+			cnt, info.msgpool);
+	}
+
+	parse_proc_sysvipc(&info);
+}
+
+static void setup(void)
+{
+	ltpuser = SAFE_GETPWNAM("nobody");
+	nobody_uid = ltpuser->pw_uid;
+	root_uid = 0;
+
+	msg_id = SAFE_MSGGET(IPC_PRIVATE, IPC_CREAT | MSG_RW);
+	SAFE_MSGSND(msg_id, "abcd", 4, 0);
+}
+
+static void cleanup(void)
+{
+	if (msg_id >= 0)
+		SAFE_MSGCTL(msg_id, IPC_RMID, NULL);
+}
+
+static struct tst_test test = {
+	.setup = setup,
+	.cleanup = cleanup,
+	.test = verify_msgctl,
+	.tcnt = ARRAY_SIZE(tests),
+	.needs_root = 1,
+};