1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) Wipro Technologies Ltd, 2002.  All Rights Reserved.
4 * Author: Saji Kumar.V.R <saji.kumar@wipro.com>
5 *
6 * Tests basic error handling of the capget syscall.
7 * 1) capget() fails with errno set to EFAULT if an invalid address
8 * is given for header.
9 * 2) capget() fails with errno set to EFAULT if an invalid address
10 * is given for data
11 * 3) capget() fails with errno set to EINVAL if an invalid value
12 * is given for header->version
13 * 4) capget() fails with errno set to EINVAL if header->pid < 0
14 * 5) capget() fails with errno set to ESRCH if the process with
15 *  pid, header->pid does not exist.
16 */
17
18#include <sys/types.h>
19#include "tst_test.h"
20#include "lapi/syscalls.h"
21#include <linux/capability.h>
22
23static pid_t unused_pid;
24static struct __user_cap_header_struct *header;
25static struct __user_cap_data_struct *data, *bad_data;
26
27static struct tcase {
28	int version;
29	int pid;
30	int exp_err;
31	int flag;
32	char *message;
33} tcases[] = {
34	{0x20080522, 0, EFAULT, 1, "bad address header"},
35	{0x20080522, 0, EFAULT, 2, "bad address data"},
36	{0, 0, EINVAL, 0, "bad version"},
37	{0x20080522, -1, EINVAL, 0, "bad pid"},
38	{0x20080522, 1, ESRCH, 0, "unused pid"},
39};
40
41static void verify_capget(unsigned int n)
42{
43	struct tcase *tc = &tcases[n];
44
45	header->version = tc->version;
46	if (tc->pid == 1)
47		header->pid = unused_pid;
48	else
49		header->pid = tc->pid;
50
51	/*
52	 * header must not be NULL. data may be NULL only when the user is
53	 * trying to determine the preferred capability version format
54	 * supported by the kernel. So use tst_get_bad_addr() to get
55	 * this error.
56	 */
57	TST_EXP_FAIL(tst_syscall(__NR_capget, tc->flag - 1 ? header : NULL,
58	                         tc->flag - 2 ? data : bad_data),
59		     tc->exp_err, "capget() with %s", tc->message);
60
61	/*
62	 * When an unsupported version value is specified, it will
63	 * return the kernel preferred value of _LINUX_CAPABILITY_VERSION_?.
64	 * Since linux 2.6.26, version 3 is default. We use it.
65	 */
66	if (header->version != 0x20080522)
67		tst_res(TFAIL, "kernel doesn't return preferred linux"
68			" capability version when using bad version");
69}
70
71static void setup(void)
72{
73	unused_pid = tst_get_unused_pid();
74	bad_data = tst_get_bad_addr(NULL);
75}
76
77static struct tst_test test = {
78	.setup = setup,
79	.tcnt = ARRAY_SIZE(tcases),
80	.test = verify_capget,
81	.bufs = (struct tst_buffers []) {
82		{&header, .size = sizeof(*header)},
83		{&data, .size = 2 * sizeof(*data)},
84		{&bad_data, .size = 2 * sizeof(*data)},
85		{},
86	}
87};
88