blob: a10b021cedc035e3f669d9eea0d25c91a698b4c5 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
|
// Copyright 2013 The Chromium 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 "mojo/system/memory.h"
#include <limits>
#include "base/logging.h"
namespace mojo {
namespace system {
// TODO(vtl): Can I make this use the non-templatized function without a
// performance hit?
template <size_t size>
bool VerifyUserPointerForSize(const void* pointer, size_t count) {
if (count > std::numeric_limits<size_t>::max() / size)
return false;
// TODO(vtl): If running in kernel mode, do a full verification. For now, just
// check that it's non-null if |size| is nonzero. (A faster user mode
// implementation is also possible if this check is skipped.)
return count == 0 || !!pointer;
}
bool MOJO_SYSTEM_IMPL_EXPORT VerifyUserPointerForSize(const void* pointer,
size_t size,
size_t count) {
if (count > std::numeric_limits<size_t>::max() / size)
return false;
// TODO(vtl): If running in kernel mode, do a full verification. For now, just
// check that it's non-null if |size| is nonzero. (A faster user mode
// implementation is also possible if this check is skipped.)
return count == 0 || !!pointer;
}
// Explicitly instantiate the sizes we need. Add instantiations as needed.
template MOJO_SYSTEM_IMPL_EXPORT bool VerifyUserPointerForSize<1>(
const void*, size_t);
template MOJO_SYSTEM_IMPL_EXPORT bool VerifyUserPointerForSize<4>(
const void*, size_t);
template MOJO_SYSTEM_IMPL_EXPORT bool VerifyUserPointerForSize<8>(
const void*, size_t);
} // namespace system
} // namespace mojo
|
