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| // Test ASan detection of stack-overflow condition when Linux sends SIGBUS.
// RUN: %clangxx_asan -O0 %s -o %t && %env_asan_opts=use_sigaltstack=1 not %run %t 2>&1 | FileCheck %s
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/resource.h>
const int BS = 1024;
volatile char x;
volatile int y = 1;
void recursive_func(char *p) {
char buf[BS];
buf[rand() % BS] = 1;
buf[rand() % BS] = 2;
x = buf[rand() % BS];
if (y)
recursive_func(buf);
x = 1; // prevent tail call optimization
// CHECK: {{stack-overflow on address 0x.* \(pc 0x.* bp 0x.* sp 0x.* T.*\)}}
}
void LimitStackAndReexec(int argc, char **argv) {
struct rlimit rlim;
int res = getrlimit(RLIMIT_STACK, &rlim);
assert(res == 0);
if (rlim.rlim_cur == RLIM_INFINITY) {
rlim.rlim_cur = 256 * 1024;
res = setrlimit(RLIMIT_STACK, &rlim);
assert(res == 0);
execv(argv[0], argv);
assert(0 && "unreachable");
}
}
int main(int argc, char **argv) {
LimitStackAndReexec(argc, argv);
// Map some memory just before the start of the current stack vma.
// When the stack grows down and crashes into it, Linux can send
// SIGBUS instead of SIGSEGV. See:
// http://lkml.iu.edu/hypermail/linux/kernel/1008.1/02299.html
const long pagesize = sysconf(_SC_PAGESIZE);
FILE *f = fopen("/proc/self/maps", "r");
char a[1000];
void *p = 0;
while (fgets(a, sizeof a, f)) {
if (strstr(a, "[stack]")) {
unsigned long addr;
if (sscanf(a, "%lx", &addr) == 1)
p = mmap((void *)(addr - 4 * pagesize), pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
}
}
assert(p);
recursive_func(0);
return 0;
}
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