1 // Test ASan detection of stack-overflow condition when Linux sends SIGBUS.
2
3 // RUN: %clangxx_asan -O0 %s -o %t && %env_asan_opts=use_sigaltstack=1 not %run %t 2>&1 | FileCheck %s
4
5 #include <assert.h>
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <string.h>
9 #include <unistd.h>
10 #include <sys/mman.h>
11 #include <sys/resource.h>
12
13 const int BS = 1024;
14 volatile char x;
15 volatile int y = 1;
16
recursive_func(char * p)17 void recursive_func(char *p) {
18 char buf[BS];
19 buf[rand() % BS] = 1;
20 buf[rand() % BS] = 2;
21 x = buf[rand() % BS];
22 if (y)
23 recursive_func(buf);
24 x = 1; // prevent tail call optimization
25 // CHECK: {{stack-overflow on address 0x.* \(pc 0x.* bp 0x.* sp 0x.* T.*\)}}
26 }
27
LimitStackAndReexec(int argc,char ** argv)28 void LimitStackAndReexec(int argc, char **argv) {
29 struct rlimit rlim;
30 int res = getrlimit(RLIMIT_STACK, &rlim);
31 assert(res == 0);
32 if (rlim.rlim_cur == RLIM_INFINITY) {
33 rlim.rlim_cur = 256 * 1024;
34 res = setrlimit(RLIMIT_STACK, &rlim);
35 assert(res == 0);
36
37 execv(argv[0], argv);
38 assert(0 && "unreachable");
39 }
40 }
41
main(int argc,char ** argv)42 int main(int argc, char **argv) {
43 LimitStackAndReexec(argc, argv);
44
45 // Map some memory just before the start of the current stack vma.
46 // When the stack grows down and crashes into it, Linux can send
47 // SIGBUS instead of SIGSEGV. See:
48 // http://lkml.iu.edu/hypermail/linux/kernel/1008.1/02299.html
49 const long pagesize = sysconf(_SC_PAGESIZE);
50 FILE *f = fopen("/proc/self/maps", "r");
51 char a[1000];
52 void *p = 0;
53 while (fgets(a, sizeof a, f)) {
54 if (strstr(a, "[stack]")) {
55 unsigned long addr;
56 if (sscanf(a, "%lx", &addr) == 1)
57 p = mmap((void *)(addr - 4 * pagesize), pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
58 }
59 }
60 assert(p);
61
62 recursive_func(0);
63 return 0;
64 }
65