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/*
* Check decoding of getdents and getdents64 syscalls.
*
* Copyright (c) 2015-2020 Dmitry V. Levin <ldv@strace.io>
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include <dirent.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/stat.h>
#include "kernel_dirent.h"
#include "print_fields.h"
#if VERBOSE
static const char *
str_d_type(const unsigned char d_type)
{
switch (d_type) {
case DT_DIR:
return "DT_DIR";
case DT_REG:
return "DT_REG";
default:
return "DT_UNKNOWN";
}
}
static void
print_dirent(const kernel_dirent_type *d);
#endif
static const char *errstr;
static long
k_getdents(const unsigned int fd,
const void *dirp,
const unsigned int count)
{
const kernel_ulong_t fill = (kernel_ulong_t) 0xdefaced00000000ULL;
const kernel_ulong_t bad = (kernel_ulong_t) 0xbadc0dedbadc0dedULL;
const kernel_ulong_t arg1 = fill | fd;
const kernel_ulong_t arg2 = (uintptr_t) dirp;
const kernel_ulong_t arg3 = fill | count;
const long rc = syscall(NR_getdents, arg1, arg2, arg3, bad, bad, bad);
errstr = sprintrc(rc);
return rc;
}
static void
ls(int fd, char *buf, unsigned int size)
{
long rc;
while ((rc = k_getdents(fd, buf, size))) {
if (rc < 0)
perror_msg_and_skip(STR_getdents);
printf("%s(%d, ", STR_getdents, fd);
#if VERBOSE
printf("[");
#else
unsigned long entries = 0;
#endif
kernel_dirent_type *d;
for (long i = 0; i < rc; i += d->d_reclen) {
d = (kernel_dirent_type *) &buf[i];
#if VERBOSE
if (i)
printf(", ");
print_dirent(d);
#else
++entries;
#endif
}
#if VERBOSE
printf("]");
#else
printf("%p /* %lu entries */", buf, entries);
#endif
printf(", %u) = %ld\n", size, rc);
}
#if VERBOSE
printf("%s(%d, [], %u) = 0\n", STR_getdents, fd, size);
#else
printf("%s(%d, %p /* 0 entries */, %u) = 0\n",
STR_getdents, fd, buf, size);
#endif
}
int
main(void)
{
static const char dot[] = ".";
static const char dot_dot[] = "..";
static const char dname[] = STR_getdents
#if VERBOSE
"-v"
#endif
".test.tmp.dir";
static const char fname[] =
"A\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\n"
"A\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\n"
"A\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\n"
"A\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\n"
"A\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\n"
"A\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\n"
"A\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\n"
"A\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nA\nZ";
if (mkdir(dname, 0700))
perror_msg_and_fail("mkdir: %s", dname);
if (chdir(dname))
perror_msg_and_fail("chdir: %s", dname);
int fd = creat(fname, 0600);
if (fd < 0)
perror_msg_and_fail("creat: %s", fname);
if (close(fd))
perror_msg_and_fail("close: %s", fname);
fd = open(dot, O_RDONLY | O_DIRECTORY);
if (fd < 0)
perror_msg_and_fail("open: %s", dot);
unsigned int count = 0xdeadbeefU;
k_getdents(-1U, NULL, count);
printf("%s(-1, NULL, %u) = %s\n", STR_getdents, count, errstr);
static char buf[8192];
ls(fd, buf, sizeof(buf));
if (unlink(fname))
perror_msg_and_fail("unlink: %s", fname);
if (chdir(dot_dot))
perror_msg_and_fail("chdir: %s", dot_dot);
if (rmdir(dname))
perror_msg_and_fail("rmdir: %s", dname);
puts("+++ exited with 0 +++");
return 0;
}
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