1 // RUN: %clangxx_msan -std=c++11 -O0 %s -o %t && %run %t 2 // RUN: %clangxx_msan -std=c++11 -O0 %s -o %t -DPOSITIVE && not %run %t |& FileCheck %s 3 4 #include <assert.h> 5 #include <dlfcn.h> 6 #include <sanitizer/msan_interface.h> 7 #include <stdio.h> 8 #include <string.h> 9 #include <sys/types.h> 10 #include <sys/uio.h> 11 #include <unistd.h> 12 #include <errno.h> 13 14 typedef ssize_t (*process_vm_readwritev_fn)(pid_t, const iovec *, unsigned long, 15 const iovec *, unsigned long, 16 unsigned long); 17 18 // Exit with success, emulating the expected output. 19 int exit_dummy() 20 { 21 #ifdef POSITIVE 22 printf("process_vm_readv not found or not implemented!\n"); 23 printf( 24 "WARNING: MemorySanitizer: use-of-uninitialized-value (not really)\n"); 25 return 1; 26 #else 27 return 0; 28 #endif 29 } 30 31 int main(void) { 32 // This requires glibc 2.15. 33 process_vm_readwritev_fn libc_process_vm_readv = 34 (process_vm_readwritev_fn)dlsym(RTLD_NEXT, "process_vm_readv"); 35 if (!libc_process_vm_readv) 36 return exit_dummy(); 37 38 process_vm_readwritev_fn process_vm_readv = 39 (process_vm_readwritev_fn)dlsym(RTLD_DEFAULT, "process_vm_readv"); 40 process_vm_readwritev_fn process_vm_writev = 41 (process_vm_readwritev_fn)dlsym(RTLD_DEFAULT, "process_vm_writev"); 42 43 char a[100]; 44 memset(a, 0xab, 100); 45 46 char b[100]; 47 iovec iov_a[] = {{(void *)a, 20}, (void *)(a + 50), 10}; 48 iovec iov_b[] = {{(void *)(b + 10), 10}, (void *)(b + 30), 20}; 49 50 __msan_poison(&b, sizeof(b)); 51 ssize_t res = process_vm_readv(getpid(), iov_b, 2, iov_a, 2, 0); 52 if (errno == ENOSYS) // Function not implemented 53 return exit_dummy(); 54 55 assert(res == 30); 56 __msan_check_mem_is_initialized(b + 10, 10); 57 __msan_check_mem_is_initialized(b + 30, 20); 58 assert(__msan_test_shadow(b + 9, 1) == 0); 59 assert(__msan_test_shadow(b + 20, 1) == 0); 60 assert(__msan_test_shadow(b + 29, 1) == 0); 61 assert(__msan_test_shadow(b + 50, 1) == 0); 62 63 #ifdef POSITIVE 64 __msan_unpoison(&b, sizeof(b)); 65 __msan_poison(b + 32, 1); 66 res = process_vm_writev(getpid(), iov_b, 2, iov_a, 2, 0); 67 // CHECK: WARNING: MemorySanitizer: use-of-uninitialized-value 68 #else 69 __msan_unpoison(&b, sizeof(b)); 70 res = process_vm_writev(getpid(), iov_b, 2, iov_a, 2, 0); 71 assert(res == 30); 72 #endif 73 74 return 0; 75 } 76
