1// Regression test for
2// http://code.google.com/p/address-sanitizer/issues/detail?id=19
3// Bug description:
4// 1. application dlopens foo.so
5// 2. asan registers all globals from foo.so
6// 3. application dlcloses foo.so
7// 4. application mmaps some memory to the location where foo.so was before
8// 5. application starts using this mmaped memory, but asan still thinks there
9// are globals.
10// 6. BOOM
11
12// This subtle test assumes that after a foo.so is dlclose-d
13// we can mmap the region of memory that was occupied by the library.
14// This test works on x86 and Darwin, but not confirmed working anywhere else.
15// REQUIRES: x86-target-arch || darwin
16
17// RUN: %clangxx_asan -O0 -DSHARED_LIB %s -fPIC -shared -o %t-so.so
18// RUN: %clangxx_asan -O0 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s
19// RUN: %clangxx_asan -O1 -DSHARED_LIB %s -fPIC -shared -o %t-so.so
20// RUN: %clangxx_asan -O1 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s
21// RUN: %clangxx_asan -O2 -DSHARED_LIB %s -fPIC -shared -o %t-so.so
22// RUN: %clangxx_asan -O2 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s
23// RUN: %clangxx_asan -O3 -DSHARED_LIB %s -fPIC -shared -o %t-so.so
24// RUN: %clangxx_asan -O3 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s
25
26// XFAIL: i386-netbsd
27
28#if !defined(SHARED_LIB)
29#include <assert.h>
30#include <dlfcn.h>
31#include <stdio.h>
32#include <string.h>
33#include <sys/mman.h>
34#include <unistd.h>
35
36#include <string>
37
38#if defined(__FreeBSD__)
39// The MAP_NORESERVE define has been removed in FreeBSD 11.x, and even before
40// that, it was never implemented. So just define it to zero.
41#undef MAP_NORESERVE
42#define MAP_NORESERVE 0
43#endif
44
45using std::string;
46
47typedef int *(fun_t)();
48
49int main(int argc, char *argv[]) {
50 string path = string(argv[0]) + "-so.so";
51 size_t PageSize = sysconf(_SC_PAGESIZE);
52 printf(format: "opening %s ... \n", path.c_str());
53 void *lib = dlopen(file: path.c_str(), RTLD_NOW);
54 if (!lib) {
55 printf(format: "error in dlopen(): %s\n", dlerror());
56 return 1;
57 }
58 fun_t *get = (fun_t*)dlsym(handle: lib, name: "get_address_of_static_var");
59 if (!get) {
60 printf(format: "failed dlsym\n");
61 return 1;
62 }
63 int *addr = get();
64 assert(((size_t)addr % 32) == 0); // should be 32-byte aligned.
65 printf(format: "addr: %p\n", addr);
66 addr[0] = 1; // make sure we can write there.
67
68 // Now dlclose the shared library.
69 printf(format: "attempting to dlclose\n");
70 if (dlclose(handle: lib)) {
71 printf(format: "failed to dlclose\n");
72 return 1;
73 }
74 // Now, the page where 'addr' is unmapped. Map it.
75 size_t page_beg = ((size_t)addr) & ~(PageSize - 1);
76 void *res = mmap(addr: (void*)(page_beg), len: PageSize,
77 PROT_READ | PROT_WRITE,
78 MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE, fd: -1, offset: 0);
79 if (res == (char*)-1L) {
80 printf(format: "failed to mmap\n");
81 return 1;
82 }
83 addr[1] = 2; // BOOM (if the bug is not fixed).
84 printf(format: "PASS\n");
85 // CHECK: PASS
86 return 0;
87}
88#else // SHARED_LIB
89#include <stdio.h>
90
91static int pad1;
92static int static_var;
93static int pad2;
94
95extern "C"
96int *get_address_of_static_var() {
97 return &static_var;
98}
99
100__attribute__((constructor))
101void at_dlopen() {
102 printf("%s: I am being dlopened\n", __FILE__);
103}
104__attribute__((destructor))
105void at_dlclose() {
106 printf("%s: I am being dlclosed\n", __FILE__);
107}
108#endif // SHARED_LIB
109

source code of compiler-rt/test/asan/TestCases/Posix/dlclose-test.cpp