mprotect system call exposed to the untrusted code.

tests/mmap/mmap_test.cc

 /*
  * Copyright (c) 2012 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <setjmp.h>
@@ skipping 251 matching lines @@
   /*
    * Note that, on Windows, NaCl's mprotect() has different code paths
    * for anonymous and file-backed mappings.  This test case only
    * covers the anonymous case.
    */
   size_t map_size = 0x20000;
   char *addr = (char *) mmap(NULL, map_size, PROT_READ | PROT_WRITE,
                              MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
   assert(addr != MAP_FAILED);
   printf("mmap done\n");
-  /*
-   * Change the protection to make the page unreadable. TODO(phosek): use
-   * the mprotect() wrapper function once mprotect() is added to the IRT.
-   */
-  int rc = NACL_SYSCALL(mprotect)(addr, map_size, PROT_NONE);
+  /* Change the protection to make the page unreadable. */
+  int rc = mprotect(addr, map_size, PROT_NONE);

[Mark Seaborn, 2012/10/14 00:47:16]

For this to work, you'll need to add an mprotect() wrapper to nacl-glibc too.

[Petr Hosek, 2012/10/14 00:53:21]

Undone.

   assert(rc == 0);
   assert_addr_is_unreadable(addr);
   assert_addr_is_unreadable(addr + 0x1000);
   assert_addr_is_unreadable(addr + 0x10000);
   /* Change the protection to make the page accessible again. */
-  rc = NACL_SYSCALL(mprotect)(addr, map_size, PROT_READ | PROT_WRITE);
+  rc = mprotect(addr, map_size, PROT_READ | PROT_WRITE);
   assert(rc == 0);
   addr[0] = '5';
   /* Change the protection to make the page read-only. */
-  rc = NACL_SYSCALL(mprotect)(addr, map_size, PROT_READ);
+  rc = mprotect(addr, map_size, PROT_READ);
   assert(rc == 0);
   assert_addr_is_unwritable(addr, '9');
   assert('5' == addr[0]);
   printf("mprotect good\n");
   /* We can still munmap() the memory. */
   rc = munmap(addr, map_size);
   assert(rc == 0);
   return true;
 }
 
@@ skipping 11 matching lines @@
    */
   size_t map_size = 0x20000;
   char *addr = (char *) mmap(NULL, map_size, PROT_READ | PROT_WRITE,
                              MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
   assert(addr != MAP_FAILED);
   printf("mmap done\n");
   /* Unmap the mapped memory region. */
   int rc = munmap(addr, map_size);
   assert(rc == 0);
   printf("munmap done\n");
-  /*
-   * Change the protection to make the page unreadable. TODO(phosek): use
-   * the mprotect() wrapper function once mprotect() is added to the IRT.
-   */
-  rc = NACL_SYSCALL(mprotect)(addr, map_size, PROT_NONE);
-  if (-EACCES == rc) {
+  /* Change the protection to make the page unreadable. */
+  rc = mprotect(addr, map_size, PROT_NONE);
+  if (-1 == rc && EACCES == errno) {
     printf("mprotect good (failed as expected)\n");
     return true;
   }
   return false;
 }
 
 
 /*
  *   Verify that the last page in a file can be mmapped when the file's
  *   size is not a multiple of the page size.
@@ skipping 108 matching lines @@
   passed = testSuite();
 
   if (passed) {
     printf("All tests PASSED\n");
     exit(0);
   } else {
     printf("One or more tests FAILED\n");
     exit(-1);
   }
 }