request_key: Add negative tests for request_key

Add negative tests for request_key(), when errno is EFAULT or EPERM

Signed-off-by: Ma Xinjian <[email protected]>
Reviewed-by: Petr Vorel <[email protected]>
Reviewed-by: Cyril Hrubis <[email protected]>

runtest/syscalls

@@ -1210,6 +1210,7 @@ request_key02 request_key02
 request_key03 request_key03
 request_key04 request_key04
 request_key05 request_key05
+request_key06 request_key06
 
 rmdir01 rmdir01
 rmdir02 rmdir02

testcases/kernel/syscalls/request_key/.gitignore

@@ -3,3 +3,4 @@
 /request_key03
 /request_key04
 /request_key05
+/request_key06

testcases/kernel/syscalls/request_key/request_key06.c

@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2024 FUJITSU LIMITED. All Rights Reserved.
+ * Author: Ma Xinjian <[email protected]>
+ */
+
+/*\
+ * [Description]
+ *
+ * Verify that request_key(2) fails with
+ *
+ * - EFAULT when type points outside the process's accessible address space
+ * - EFAULT when description points outside the process's accessible address space
+ * - EFAULT when callout_info points outside the process's accessible address space
+ * - EPERM when type argument started with a period '.'
+ */
+
+#include "tst_test.h"
+#include "lapi/keyctl.h"
+
+static struct test_case_t {
+	char *type;
+	char *description;
+	char *callout_info;
+	key_serial_t dest_keyring;
+	int expected_errno;
+	char *desc;
+} tcases[] = {
+	{(char *)(-1), "description", NULL, KEY_SPEC_PROCESS_KEYRING, EFAULT,
+		"type points outside the process's accessible address space"},
+	{"type", (char *)(-1), NULL, KEY_SPEC_PROCESS_KEYRING, EFAULT,
+		"description points outside the process's accessible address space"},
+	{"type", "description", (char *)(-1), KEY_SPEC_PROCESS_KEYRING, EFAULT,
+		"callout_info points outside the process's accessible address space"},
+	{".type", "description", NULL, KEY_SPEC_PROCESS_KEYRING, EPERM,
+		"type argument started with a period '.'"},
+};
+
+static void verify_request_key(unsigned int i)
+{
+	struct test_case_t *tc = &tcases[i];
+
+	TST_EXP_FAIL2(request_key(tc->type, tc->description, tc->callout_info,
+		tc->dest_keyring),
+		tc->expected_errno,
+		"%s", tc->desc);
+}
+
+static struct tst_test test = {
+	.tcnt = ARRAY_SIZE(tcases),
+	.test = verify_request_key,
+};