76 lines · cpp
1// RUN: %clangxx_msan -std=c++11 -O0 %s -o %t && %run %t2// RUN: %clangxx_msan -std=c++11 -O0 %s -o %t -DPOSITIVE && not %run %t 2>&1 | FileCheck %s3 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 14typedef 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.19int exit_dummy()20{21#ifdef POSITIVE22 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#else27 return 0;28#endif29}30 31int 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 POSITIVE64 __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-value68#else69 __msan_unpoison(&b, sizeof(b));70 res = process_vm_writev(getpid(), iov_b, 2, iov_a, 2, 0);71 assert(res == 30);72#endif73 74 return 0;75}76