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| // RUN: %clangxx_msan -std=c++11 -O0 %s -o %t && %run %t
// RUN: %clangxx_msan -std=c++11 -O0 %s -o %t -DPOSITIVE && not %run %t 2>&1 | FileCheck %s
#include <assert.h>
#include <dlfcn.h>
#include <sanitizer/msan_interface.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <unistd.h>
#include <errno.h>
typedef ssize_t (*process_vm_readwritev_fn)(pid_t, const iovec *, unsigned long,
const iovec *, unsigned long,
unsigned long);
// Exit with success, emulating the expected output.
int exit_dummy()
{
#ifdef POSITIVE
printf("process_vm_readv not found or not implemented!\n");
printf(
"WARNING: MemorySanitizer: use-of-uninitialized-value (not really)\n");
return 1;
#else
return 0;
#endif
}
int main(void) {
// This requires glibc 2.15.
process_vm_readwritev_fn libc_process_vm_readv =
(process_vm_readwritev_fn)dlsym(RTLD_NEXT, "process_vm_readv");
if (!libc_process_vm_readv)
return exit_dummy();
process_vm_readwritev_fn process_vm_readv =
(process_vm_readwritev_fn)dlsym(RTLD_DEFAULT, "process_vm_readv");
process_vm_readwritev_fn process_vm_writev =
(process_vm_readwritev_fn)dlsym(RTLD_DEFAULT, "process_vm_writev");
char a[100];
memset(a, 0xab, 100);
char b[100];
iovec iov_a[] = {{(void *)a, 20}, (void *)(a + 50), 10};
iovec iov_b[] = {{(void *)(b + 10), 10}, (void *)(b + 30), 20};
__msan_poison(&b, sizeof(b));
ssize_t res = process_vm_readv(getpid(), iov_b, 2, iov_a, 2, 0);
if (errno == ENOSYS) // Function not implemented
return exit_dummy();
assert(res == 30);
__msan_check_mem_is_initialized(b + 10, 10);
__msan_check_mem_is_initialized(b + 30, 20);
assert(__msan_test_shadow(b + 9, 1) == 0);
assert(__msan_test_shadow(b + 20, 1) == 0);
assert(__msan_test_shadow(b + 29, 1) == 0);
assert(__msan_test_shadow(b + 50, 1) == 0);
#ifdef POSITIVE
__msan_unpoison(&b, sizeof(b));
__msan_poison(b + 32, 1);
res = process_vm_writev(getpid(), iov_b, 2, iov_a, 2, 0);
// CHECK: WARNING: MemorySanitizer: use-of-uninitialized-value
#else
__msan_unpoison(&b, sizeof(b));
res = process_vm_writev(getpid(), iov_b, 2, iov_a, 2, 0);
assert(res == 30);
#endif
return 0;
}
|