1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) International Business Machines Corp., 2001
4 * 07/2001 Ported by John George
5 * 04/2002 wjhuie sigset cleanups
6 * 08/2007 Ricardo Salveti de Araujo <[email protected]>
7 * Copyright (c) Linux Test Project, 2002-2023
8 */
9
10 /*\
11 * [Description]
12 *
13 * Check the return value, and errnos of write(2)
14 *
15 * - when the file descriptor is invalid - EBADF
16 * - when the buf parameter is invalid - EFAULT
17 * - on an attempt to write to a pipe that is not open for reading - EPIPE
18 */
19
20 #include <sys/types.h>
21 #include <sys/stat.h>
22 #include <fcntl.h>
23 #include <errno.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <sys/wait.h>
27 #include <sys/mman.h>
28 #include "tst_test.h"
29
30 static int fd;
31 static int inv_fd = -1;
32 static char b[32];
33 static char *buf = b;
34 static char *bad_addr;
35 static int pipefd[2];
36
37 static struct tcase {
38 int *fd;
39 char **buf;
40 size_t size;
41 int exp_errno;
42 } tcases[] = {
43 {&inv_fd, &buf, sizeof(buf), EBADF},
44 {&fd, &bad_addr, sizeof(buf), EFAULT},
45 {&pipefd[1], &buf, sizeof(buf), EPIPE},
46 };
47
48 static volatile int sigpipe_cnt;
49
sighandler(int sig)50 static void sighandler(int sig)
51 {
52 if (sig == SIGPIPE)
53 sigpipe_cnt++;
54 }
55
verify_write(unsigned int i)56 static void verify_write(unsigned int i)
57 {
58 struct tcase *tc = &tcases[i];
59
60 sigpipe_cnt = 0;
61
62 TST_EXP_FAIL2(write(*tc->fd, *tc->buf, tc->size), tc->exp_errno);
63 if (TST_RET != -1)
64 return;
65
66 if (tc->exp_errno == EPIPE && sigpipe_cnt != 1)
67 tst_res(TFAIL, "sigpipe_cnt = %i", sigpipe_cnt);
68 }
69
setup(void)70 static void setup(void)
71 {
72 fd = SAFE_OPEN("write_test", O_RDWR | O_CREAT, 0644);
73
74 bad_addr = SAFE_MMAP(0, 1, PROT_NONE,
75 MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
76
77 SAFE_PIPE(pipefd);
78 SAFE_CLOSE(pipefd[0]);
79
80 SAFE_SIGNAL(SIGPIPE, sighandler);
81 }
82
cleanup(void)83 static void cleanup(void)
84 {
85 if (fd > 0)
86 SAFE_CLOSE(fd);
87
88 SAFE_MUNMAP(bad_addr, 1);
89 }
90
91 static struct tst_test test = {
92 .needs_tmpdir = 1,
93 .setup = setup,
94 .cleanup = cleanup,
95 .test = verify_write,
96 .tcnt = ARRAY_SIZE(tcases),
97 };
98