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
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
// RUN: %clang_esan_wset -O0 %s -o %t 2>&1
// RUN: %run %t 2>&1 | FileCheck %s
// Stucks at init and no clone feature equivalent.
// UNSUPPORTED: freebsd
#include <assert.h>
#include <setjmp.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
sigjmp_buf mark;
static void SignalHandler(int Sig) {
if (Sig == SIGSEGV) {
fprintf(stderr, "Handling SIGSEGV for signal\n");
siglongjmp(mark, 1);
}
exit(1);
}
static void SigactionHandler(int Sig, siginfo_t *Info, void *Ctx) {
if (Sig == SIGSEGV) {
fprintf(stderr, "Handling SIGSEGV for sigaction\n");
siglongjmp(mark, 1);
}
exit(1);
}
int main(int argc, char **argv) {
__sighandler_t Prior = signal(SIGSEGV, SignalHandler);
assert(Prior == SIG_DFL);
if (sigsetjmp(mark, 1) == 0)
*((volatile int *)(ssize_t)argc) = 42; // Raise SIGSEGV
fprintf(stderr, "Past longjmp for signal\n");
Prior = signal(SIGSEGV, SIG_DFL);
assert(Prior == SignalHandler);
struct sigaction SigAct;
SigAct.sa_sigaction = SigactionHandler;
int Res = sigfillset(&SigAct.sa_mask);
assert(Res == 0);
SigAct.sa_flags = SA_SIGINFO;
Res = sigaction(SIGSEGV, &SigAct, NULL);
assert(Res == 0);
if (sigsetjmp(mark, 1) == 0)
*((volatile int *)(ssize_t)argc) = 42; // Raise SIGSEGV
fprintf(stderr, "Past longjmp for sigaction\n");
Res = sigaction(SIGSEGV, NULL, &SigAct);
assert(Res == 0);
assert(SigAct.sa_sigaction == SigactionHandler);
// Test blocking SIGSEGV and raising a shadow fault.
sigset_t Set;
sigemptyset(&Set);
sigaddset(&Set, SIGSEGV);
Res = sigprocmask(SIG_BLOCK, &Set, NULL);
// Make a large enough mapping that its start point will be before any
// prior library-region shadow access.
char *buf = (char *)mmap(0, 640*1024, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
buf[0] = 4;
munmap(buf, 640*1024);
fprintf(stderr, "Past blocked-SIGSEGV shadow fault\n");
return 0;
}
// CHECK: Handling SIGSEGV for signal
// CHECK-NEXT: Past longjmp for signal
// CHECK-NEXT: Handling SIGSEGV for sigaction
// CHECK-NEXT: Past longjmp for sigaction
// CHECK-NEXT: Past blocked-SIGSEGV shadow fault
// CHECK: {{.*}} EfficiencySanitizer: the total working set size: {{[0-9]+}} Bytes ({{[0-9][0-9]}} cache lines)
|
