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
52
53
| // RUN: %clang_scudo %s -o %t
// RUN: %run %t after 2>&1 | FileCheck %s
// RUN: %run %t before 2>&1 | FileCheck %s
// Test that we hit a guard page when writing past the end of a chunk
// allocated by the Secondary allocator, or writing too far in front of it.
#include <assert.h>
#include <malloc.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
void handler(int signo, siginfo_t *info, void *uctx) {
if (info->si_code == SEGV_ACCERR) {
fprintf(stderr, "SCUDO SIGSEGV\n");
exit(0);
}
exit(1);
}
int main(int argc, char **argv)
{
// The size must be large enough to be serviced by the secondary allocator.
long page_size = sysconf(_SC_PAGESIZE);
size_t size = (1U << 17) + page_size;
struct sigaction a;
assert(argc == 2);
memset(&a, 0, sizeof(a));
a.sa_sigaction = handler;
a.sa_flags = SA_SIGINFO;
char *p = (char *)malloc(size);
assert(p);
memset(p, 'A', size); // This should not trigger anything.
// Set up the SIGSEGV handler now, as the rest should trigger an AV.
sigaction(SIGSEGV, &a, NULL);
if (!strcmp(argv[1], "after")) {
for (int i = 0; i < page_size; i++)
p[size + i] = 'A';
}
if (!strcmp(argv[1], "before")) {
for (int i = 1; i < page_size; i++)
p[-i] = 'A';
}
free(p);
return 1; // A successful test means we shouldn't reach this.
}
// CHECK: SCUDO SIGSEGV
|