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
13const int BS = 1024;
14volatile char x;
15volatile int y = 1;
16
17void 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(p: buf);
24 x = 1; // prevent tail call optimization
25 // CHECK: {{stack-overflow on address 0x.* \(pc 0x.* bp 0x.* sp 0x.* T.*\)}}
26}
27
28void LimitStackAndReexec(int argc, char **argv) {
29 struct rlimit rlim;
30 int res = getrlimit(RLIMIT_STACK, rlimits: &rlim);
31 assert(res == 0);
32 if (rlim.rlim_cur == RLIM_INFINITY) {
33 rlim.rlim_cur = 256 * 1024;
34 res = setrlimit(RLIMIT_STACK, rlimits: &rlim);
35 assert(res == 0);
36
37 execv(path: argv[0], argv: argv);
38 assert(0 && "unreachable");
39 }
40}
41
42int 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(filename: "/proc/self/maps", modes: "r");
51 char a[1000];
52 void *p = 0;
53 while (fgets(s: a, n: sizeof a, stream: f)) {
54 if (strstr(haystack: a, needle: "[stack]")) {
55 unsigned long addr;
56 if (sscanf(s: a, format: "%lx", &addr) == 1)
57 p = mmap(addr: (void *)(addr - 4 * pagesize), len: pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, fd: -1, offset: 0);
58 }
59 }
60 assert(p);
61
62 recursive_func(p: 0);
63 return 0;
64}
65

source code of compiler-rt/test/asan/TestCases/Linux/stack-overflow-sigbus.cpp