read_vsyscall.c

 1// SPDX-License-Identifier: GPL-2.0
 2/* Copyright (C) 2024. Huawei Technologies Co., Ltd */
 3#include "test_progs.h"
 4#include "read_vsyscall.skel.h"
 5
 6#if defined(__x86_64__)
 7/* For VSYSCALL_ADDR */
 8#include <asm/vsyscall.h>
 9#else
10/* To prevent build failure on non-x86 arch */
11#define VSYSCALL_ADDR 0UL
12#endif
13
14struct read_ret_desc {
15	const char *name;
16	int ret;
17} all_read[] = {
18	{ .name = "probe_read_kernel", .ret = -ERANGE },
19	{ .name = "probe_read_kernel_str", .ret = -ERANGE },
20	{ .name = "probe_read", .ret = -ERANGE },
21	{ .name = "probe_read_str", .ret = -ERANGE },
22	{ .name = "probe_read_user", .ret = -EFAULT },
23	{ .name = "probe_read_user_str", .ret = -EFAULT },
24	{ .name = "copy_from_user", .ret = -EFAULT },
25	{ .name = "copy_from_user_task", .ret = -EFAULT },
26	{ .name = "copy_from_user_str", .ret = -EFAULT },
27	{ .name = "copy_from_user_task_str", .ret = -EFAULT },
28};
29
30void test_read_vsyscall(void)
31{
32	struct read_vsyscall *skel;
33	unsigned int i;
34	int err;
35
36#if !defined(__x86_64__)
37	test__skip();
38	return;
39#endif
40	skel = read_vsyscall__open_and_load();
41	if (!ASSERT_OK_PTR(skel, "read_vsyscall open_load"))
42		return;
43
44	skel->bss->target_pid = getpid();
45	err = read_vsyscall__attach(skel);
46	if (!ASSERT_EQ(err, 0, "read_vsyscall attach"))
47		goto out;
48
49	/* userspace may don't have vsyscall page due to LEGACY_VSYSCALL_NONE,
50	 * but it doesn't affect the returned error codes.
51	 */
52	skel->bss->user_ptr = (void *)VSYSCALL_ADDR;
53	usleep(1);
54
55	for (i = 0; i < ARRAY_SIZE(all_read); i++)
56		ASSERT_EQ(skel->bss->read_ret[i], all_read[i].ret, all_read[i].name);
57out:
58	read_vsyscall__destroy(skel);
59}