llvm-project/compiler-rt/test/msan/Linux/syscalls.cpp

// RUN: %clangxx_msan -O0 %s -o %t && %run %t 2>&1
// RUN: %clangxx_msan -O3 %s -o %t && %run %t 2>&1

#include <assert.h>
#include <errno.h>
#include <glob.h>
#include <stdio.h>
#include <string.h>

#include <linux/aio_abi.h>
#include <signal.h>
#include <sys/epoll.h>
#include <sys/ptrace.h>
#include <sys/stat.h>
#include <sys/uio.h>

#include <sanitizer/linux_syscall_hooks.h>
#include <sanitizer/msan_interface.h>

/* Test the presence of __sanitizer_syscall_ in the tool runtime, and general
   sanity of their behaviour. */

int main(int argc, char *argv[]) {
  char buf[1000] __attribute__((aligned(8)));
  const int kTen = 10;
  const int kFortyTwo = 42;
  memset(buf, 0, sizeof(buf));
  __msan_unpoison(buf, sizeof(buf));
  __sanitizer_syscall_pre_recvmsg(0, buf, 0);
  __sanitizer_syscall_pre_rt_sigpending(buf, kTen);
  __sanitizer_syscall_pre_getdents(0, buf, kTen);
  __sanitizer_syscall_pre_getdents64(0, buf, kTen);

  __msan_unpoison(buf, sizeof(buf));
  __sanitizer_syscall_post_recvmsg(0, 0, buf, 0);
  __sanitizer_syscall_post_rt_sigpending(-1, buf, kTen);
  __sanitizer_syscall_post_getdents(0, 0, buf, kTen);
  __sanitizer_syscall_post_getdents64(0, 0, buf, kTen);
  assert(__msan_test_shadow(buf, sizeof(buf)) == -1);

  __msan_unpoison(buf, sizeof(buf));
  __sanitizer_syscall_post_recvmsg(kTen, 0, buf, 0);

  // Tell the kernel that the output struct size is 10 bytes, verify that those
  // bytes are unpoisoned, and the next byte is not.
  __msan_poison(buf, kTen + 1);
  __sanitizer_syscall_post_rt_sigpending(0, buf, kTen);
  assert(__msan_test_shadow(buf, sizeof(buf)) == kTen);

  __msan_poison(buf, kTen + 1);
  __sanitizer_syscall_post_getdents(kTen, 0, buf, kTen);
  assert(__msan_test_shadow(buf, sizeof(buf)) == kTen);

  __msan_poison(buf, kTen + 1);
  __sanitizer_syscall_post_getdents64(kTen, 0, buf, kTen);
  assert(__msan_test_shadow(buf, sizeof(buf)) == kTen);

  __msan_poison(buf, sizeof(buf));
  __sanitizer_syscall_post_clock_getres(0, 0, buf);
  assert(__msan_test_shadow(buf, sizeof(buf)) == sizeof(long) * 2);

  __msan_poison(buf, sizeof(buf));
  __sanitizer_syscall_post_clock_gettime(0, 0, buf);
  assert(__msan_test_shadow(buf, sizeof(buf)) == sizeof(long) * 2);

  // Failed syscall does not write to the buffer.
  __msan_poison(buf, sizeof(buf));
  __sanitizer_syscall_post_clock_gettime(-1, 0, buf);
  assert(__msan_test_shadow(buf, sizeof(buf)) == 0);

  __msan_poison(buf, sizeof(buf));
  __sanitizer_syscall_post_read(5, 42, buf, 10);
  assert(__msan_test_shadow(buf, sizeof(buf)) == 5);

  __msan_poison(buf, sizeof(buf));
  __sanitizer_syscall_post_newfstatat(0, 5, "/path/to/file", buf, 0);
  assert(__msan_test_shadow(buf, sizeof(buf)) == sizeof(struct stat));

  __msan_poison(buf, sizeof(buf));
  int prio = 0;
  __sanitizer_syscall_post_mq_timedreceive(kFortyTwo, 5, buf, sizeof(buf), &prio, 0);
  assert(__msan_test_shadow(buf, sizeof(buf)) == kFortyTwo);
  assert(__msan_test_shadow(&prio, sizeof(prio)) == -1);

  __msan_poison(buf, sizeof(buf));
  __sanitizer_syscall_post_ptrace(0, PTRACE_PEEKUSER, kFortyTwo, 0xABCD, buf);
  assert(__msan_test_shadow(buf, sizeof(buf)) == sizeof(void *));

  __msan_poison(buf, sizeof(buf));
  struct iocb iocb[3];
  struct iocb *iocbp[3] = { &iocb[0], &iocb[1], &iocb[2] };
  memset(iocb, 0, sizeof(iocb));
  iocb[0].aio_lio_opcode = IOCB_CMD_PREAD;
  iocb[0].aio_buf = (__u64)buf;
  iocb[0].aio_nbytes = 10;
  iocb[1].aio_lio_opcode = IOCB_CMD_PREAD;
  iocb[1].aio_buf = (__u64)(&buf[20]);
  iocb[1].aio_nbytes = 15;
  struct iovec vec[2] = { {&buf[40], 3}, {&buf[50], 20} };
  iocb[2].aio_lio_opcode = IOCB_CMD_PREADV;
  iocb[2].aio_buf = (__u64)(&vec);
  iocb[2].aio_nbytes = 2;
  __sanitizer_syscall_pre_io_submit(0, 3, &iocbp);
  assert(__msan_test_shadow(buf, sizeof(buf)) == 10);
  assert(__msan_test_shadow(buf + 20, sizeof(buf) - 20) == 15);
  assert(__msan_test_shadow(buf + 40, sizeof(buf) - 40) == 3);
  assert(__msan_test_shadow(buf + 50, sizeof(buf) - 50) == 20);

  __msan_poison(buf, sizeof(buf));
  char *p = buf;
  __msan_poison(&p, sizeof(p));
  __sanitizer_syscall_post_io_setup(0, 1, &p);
  assert(__msan_test_shadow(&p, sizeof(p)) == -1);
  assert(__msan_test_shadow(buf, sizeof(buf)) >= 32);

  __msan_poison(buf, sizeof(buf));
  __sanitizer_syscall_post_pipe(0, (int *)buf);
  assert(__msan_test_shadow(buf, sizeof(buf)) == 2 * sizeof(int));

  __msan_poison(buf, sizeof(buf));
  __sanitizer_syscall_post_pipe2(0, (int *)buf, 0);
  assert(__msan_test_shadow(buf, sizeof(buf)) == 2 * sizeof(int));

  __msan_poison(buf, sizeof(buf));
  __sanitizer_syscall_post_socketpair(0, 0, 0, 0, (int *)buf);
  assert(__msan_test_shadow(buf, sizeof(buf)) == 2 * sizeof(int));

  __msan_poison(buf, sizeof(buf));
  __sanitizer_syscall_post_sigaltstack(0, nullptr, (stack_t *)buf);
  assert(__msan_test_shadow(buf, sizeof(buf)) == sizeof(stack_t));

  __msan_poison(buf, sizeof(buf));
  long max_events = sizeof(buf) / sizeof(epoll_event);
  __sanitizer_syscall_pre_epoll_wait(0, buf, max_events, 0);
  __sanitizer_syscall_post_epoll_wait(max_events, 0, buf, max_events, 0);
  assert(__msan_test_shadow(buf, sizeof(buf)) == max_events * sizeof(epoll_event));

  __msan_poison(buf, sizeof(buf));
  sigset_t sigset = {};
  __sanitizer_syscall_pre_epoll_pwait(0, buf, max_events, 0, &sigset, sizeof(sigset));
  __sanitizer_syscall_post_epoll_pwait(max_events, 0, buf, max_events, 0, &sigset, sizeof(sigset));
  assert(__msan_test_shadow(buf, sizeof(buf)) == max_events * sizeof(epoll_event));

  __msan_poison(buf, sizeof(buf));
  sigset = {};
  timespec timespec = {};
  __sanitizer_syscall_pre_epoll_pwait2(0, buf, max_events, &timespec,
                                       &sigset, sizeof(sigset));
  __sanitizer_syscall_post_epoll_pwait2(max_events, 0, buf, max_events,
                                        &timespec, &sigset, sizeof(sigset));
  assert(__msan_test_shadow(buf, sizeof(buf)) == max_events * sizeof(epoll_event));

  return 0;
}