syscalls/msgget04: Add test for /proc/sys/kernel/msg_next_id

Signed-off-by: Yang Xu <[email protected]>
Reviewed-by: Cyril Hrubis <[email protected]>

Author: xuyang0410

runtest/syscalls

@@ -810,6 +810,7 @@ msgctl12 msgctl12
 msgget01 msgget01
 msgget02 msgget02
 msgget03 msgget03
+msgget04 msgget04
 
 msgrcv01 msgrcv01
 msgrcv02 msgrcv02

runtest/syscalls-ipc

@@ -12,6 +12,7 @@ msgctl12 msgctl12
 msgget01 msgget01
 msgget02 msgget02
 msgget03 msgget03
+msgget04 msgget04
 
 msgrcv01 msgrcv01
 msgrcv02 msgrcv02

testcases/kernel/syscalls/ipc/msgget/.gitignore

@@ -1,3 +1,4 @@
 /msgget01
 /msgget02
 /msgget03
+/msgget04

testcases/kernel/syscalls/ipc/msgget/msgget04.c

@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2020 FUJITSU LIMITED. All rights reserved.
+ * Author: Yang Xu <[email protected]>
+ *
+ * It is a basic test about msg_next_id.
+ * msg_next_id specifies desired id for next allocated IPC message. By default
+ * they are equal to -1, which means generic allocation logic. Possible values
+ * to set are in range {0..INT_MAX}.
+ * Toggle with non-default value will be set back to -1 by kernel after
+ * successful IPC object allocation.
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/ipc.h>
+#include <sys/msg.h>
+#include "tst_test.h"
+#include "tst_safe_sysv_ipc.h"
+#include "libnewipc.h"
+
+#define NEXT_ID_PATH "/proc/sys/kernel/msg_next_id"
+static int queue_id, pid;
+static key_t msgkey;
+
+static void verify_msgget(void)
+{
+	SAFE_FILE_PRINTF(NEXT_ID_PATH, "%d", pid);
+
+	queue_id = SAFE_MSGGET(msgkey, IPC_CREAT | MSG_RW);
+	if (queue_id == pid)
+		tst_res(TPASS, "msg_next_id succeeded, queue id %d", pid);
+	else
+		tst_res(TFAIL, "msg_next_id failed, expected id %d, but got %d", pid, queue_id);
+
+	TST_ASSERT_INT(NEXT_ID_PATH, -1);
+	SAFE_MSGCTL(queue_id, IPC_RMID, NULL);
+	pid++;
+}
+
+static void setup(void)
+{
+	msgkey = GETIPCKEY();
+	pid = getpid();
+}
+
+static void cleanup(void)
+{
+	if (queue_id != -1)
+		SAFE_MSGCTL(queue_id, IPC_RMID, NULL);
+}
+
+static struct tst_test test = {
+	.setup = setup,
+	.cleanup = cleanup,
+	.test_all = verify_msgget,
+	.needs_kconfigs = (const char *[]) {
+		"CONFIG_CHECKPOINT_RESTORE=y",
+		NULL
+	},
+	.needs_root = 1,
+};