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//===-- asan_rtl.cc ------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of AddressSanitizer, an address sanity checker.
//
// Regression test for
// http://code.google.com/p/address-sanitizer/issues/detail?id=19
// Bug description:
// 1. application dlopens foo.so
// 2. asan registers all globals from foo.so
// 3. application dlcloses foo.so
// 4. application mmaps some memory to the location where foo.so was before
// 5. application starts using this mmaped memory, but asan still thinks there
// are globals.
// 6. BOOM
//===----------------------------------------------------------------------===//
#include <assert.h>
#include <dlfcn.h>
#include <stdio.h>
#include <string.h>
#include <sys/mman.h>
#include <string>
using std::string;
static const int kPageSize = 4096;
typedef int *(fun_t)();
int main(int argc, char *argv[]) {
string path = string(argv[0]) + "-so.so";
printf("opening %s ... \n", path.c_str());
void *lib = dlopen(path.c_str(), RTLD_NOW);
if (!lib) {
printf("error in dlopen(): %s\n", dlerror());
return 1;
}
fun_t *get = (fun_t*)dlsym(lib, "get_address_of_static_var");
if (!get) {
printf("failed dlsym\n");
return 1;
}
int *addr = get();
assert(((size_t)addr % 32) == 0); // should be 32-byte aligned.
printf("addr: %p\n", addr);
addr[0] = 1; // make sure we can write there.
// Now dlclose the shared library.
printf("attempting to dlclose\n");
if (dlclose(lib)) {
printf("failed to dlclose\n");
return 1;
}
// Now, the page where 'addr' is unmapped. Map it.
size_t page_beg = ((size_t)addr) & ~(kPageSize - 1);
void *res = mmap((void*)(page_beg), kPageSize,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE, 0, 0);
if (res == (char*)-1L) {
printf("failed to mmap\n");
return 1;
}
addr[1] = 2; // BOOM (if the bug is not fixed).
printf("PASS\n");
return 0;
}
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