1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
8 #include "base/logging.h"
9 #include "components/nacl/loader/nonsfi/irt_interfaces.h"
10 #include "components/nacl/loader/nonsfi/irt_util.h"
11 #include "native_client/src/trusted/service_runtime/include/machine/_types.h"
12 #include "native_client/src/trusted/service_runtime/include/sys/mman.h"
18 int NaClProtToProt(int nacl_prot) {
20 if ((nacl_prot & NACL_ABI_PROT_MASK) == NACL_ABI_PROT_NONE)
23 if (nacl_prot & NACL_ABI_PROT_READ)
25 if (nacl_prot & NACL_ABI_PROT_WRITE)
27 if (nacl_prot & NACL_ABI_PROT_EXEC)
32 int NaClFlagsToFlags(int nacl_flags) {
35 if (nacl_flags & NACL_ABI_MAP_SHARED)
37 if (nacl_flags & NACL_ABI_MAP_PRIVATE)
39 if (nacl_flags & NACL_ABI_MAP_FIXED)
42 // Note: NACL_ABI_MAP_ANON is an alias of NACL_ABI_MAP_ANONYMOUS.
43 if (nacl_flags & NACL_ABI_MAP_ANONYMOUS)
44 flags |= MAP_ANONYMOUS;
48 int IrtMMap(void** addr, size_t len, int prot, int flags,
49 int fd, nacl_abi_off_t off) {
50 const int host_prot = NaClProtToProt(prot);
51 // On Chrome OS, mmap can fail if PROT_EXEC is set in |host_prot|,
52 // but mprotect will allow changing the permissions later.
53 // This is because Chrome OS mounts writable filesystems with "noexec".
55 *addr, len, host_prot & ~PROT_EXEC, NaClFlagsToFlags(flags), fd, off);
56 if (result == MAP_FAILED)
58 if (host_prot & PROT_EXEC) {
59 if (mprotect(result, len, host_prot) != 0) {
60 // This aborts here because it cannot easily undo the mmap() call.
61 LOG_ERRNO(FATAL) << "IrtMMap: mprotect to turn on PROT_EXEC failed.";
69 int IrtMUnmap(void* addr, size_t len) {
70 return CheckError(munmap(addr, len));
73 int IrtMProtect(void* addr, size_t len, int prot) {
74 return CheckError(mprotect(addr, len, NaClProtToProt(prot)));
79 // For mmap, the argument types should be nacl_abi_off_t rather than off_t.
80 // However, the definition of nacl_irt_memory uses the host type off_t, so here
81 // we need to cast it.
82 const nacl_irt_memory kIrtMemory = {
83 reinterpret_cast<int(*)(void**, size_t, int, int, int, off_t)>(IrtMMap),