getcpu: Add testcase for EFAULT

Add a testcase with the arguments point to an invalid address.

Link: https://lore.kernel.org/ltp/[email protected]/
Reviewed-by: Petr Vorel <[email protected]>
Signed-off-by: Ma Xinjian <[email protected]>

runtest/syscalls

@@ -448,6 +448,7 @@ futimesat01 futimesat01
 getcontext01 getcontext01
 
 getcpu01 getcpu01
+getcpu02 getcpu02
 
 getcwd01 getcwd01
 getcwd02 getcwd02

testcases/kernel/syscalls/getcpu/.gitignore

@@ -1 +1,2 @@
 /getcpu01
+/getcpu02

testcases/kernel/syscalls/getcpu/getcpu02.c

@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2024 FUJITSU LIMITED. All Rights Reserved.
+ * Copyright (c) Linux Test Project, 2024
+ * Author: Ma Xinjian <[email protected]>
+ */
+
+/*\
+ * [Description]
+ *
+ * Verify that getcpu(2) fails with EFAULT if cpu_id or node_id points outside
+ * the calling process address space.
+ */
+
+#define _GNU_SOURCE
+
+#include "tst_test.h"
+#include "lapi/sched.h"
+
+static unsigned int cpu_id, node_id;
+
+static struct tcase {
+	unsigned int *cpu_id;
+	unsigned int *node_id;
+	char *desc;
+} tcases[] = {
+	{NULL, &node_id, "cpu_id"},
+	{&cpu_id, NULL, "node_id"},
+};
+
+static void check_getcpu(unsigned int n)
+{
+	struct tcase *tc = &tcases[n];
+	int status;
+	pid_t pid;
+
+	tst_res(TINFO, "Test %s outside process address space", tc->desc);
+
+	if (!tc->cpu_id)
+		tc->cpu_id = tst_get_bad_addr(NULL);
+
+	if (!tc->node_id)
+		tc->node_id = tst_get_bad_addr(NULL);
+
+	pid = SAFE_FORK();
+	if (!pid) {
+		TST_EXP_FAIL(getcpu(tc->cpu_id, tc->node_id), EFAULT);
+
+		exit(0);
+	}
+
+	SAFE_WAITPID(pid, &status, 0);
+
+	if (WIFSIGNALED(status) && WTERMSIG(status) == SIGSEGV) {
+		tst_res(TPASS, "getcpu() caused SIGSEGV");
+		return;
+	}
+
+	if (WIFEXITED(status) && WEXITSTATUS(status) == 0)
+		return;
+
+	tst_res(TFAIL, "child %s", tst_strstatus(status));
+}
+
+static struct tst_test test = {
+	.test = check_getcpu,
+	.tcnt = ARRAY_SIZE(tcases),
+	.forks_child = 1,
+};