blob: 2281c8af6298959bdd4e9d3f12e04ccf47611701 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
|
/*
* gcc unlink_failure.c -o unlink_failure.so -shared -ldl
* LD_PRELOAD=./unlink_failure.so FAILURE_PATH=/etc/shadow ./test /etc/shadow
*/
#define _GNU_SOURCE
#include <dlfcn.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdarg.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
typedef int (*unlink_type) (const char *path);
static unlink_type next_unlink;
static const char *failure_path = NULL;
int unlink (const char *path)
{
if (NULL == next_unlink)
{
next_unlink = dlsym (RTLD_NEXT, "unlink");
assert (NULL != next_unlink);
}
if (NULL == failure_path) {
failure_path = getenv ("FAILURE_PATH");
if (NULL == failure_path) {
fputs ("No FAILURE_PATH defined\n", stderr);
}
}
if ( (NULL != path)
&& (NULL != failure_path)
&& (strcmp (path, failure_path) == 0))
{
fprintf (stderr, "unlink FAILURE %s\n", path);
errno = EBUSY;
return -1;
}
return next_unlink (path);
}
|
