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
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
|
//===-- fuchsia.cpp ---------------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "platform.h"
#if SCUDO_FUCHSIA
#include "common.h"
#include "mutex.h"
#include "string_utils.h"
#error #include <lib/sync/mutex.h> // for sync_mutex_t
#include <stdlib.h> // for getenv()
#error #include <zircon/compiler.h>
#error #include <zircon/process.h>
#error #include <zircon/sanitizer.h>
#error #include <zircon/status.h>
#error #include <zircon/syscalls.h>
namespace scudo {
uptr getPageSize() { return _zx_system_get_page_size(); }
void NORETURN die() { __builtin_trap(); }
// We zero-initialize the Extra parameter of map(), make sure this is consistent
// with ZX_HANDLE_INVALID.
static_assert(ZX_HANDLE_INVALID == 0, "");
static void NORETURN dieOnError(zx_status_t Status, const char *FnName,
uptr Size) {
char Error[128];
formatString(Error, sizeof(Error),
"SCUDO ERROR: %s failed with size %zuKB (%s)", FnName,
Size >> 10, zx_status_get_string(Status));
outputRaw(Error);
die();
}
static void *allocateVmar(uptr Size, MapPlatformData *Data, bool AllowNoMem) {
// Only scenario so far.
DCHECK(Data);
DCHECK_EQ(Data->Vmar, ZX_HANDLE_INVALID);
const zx_status_t Status = _zx_vmar_allocate(
_zx_vmar_root_self(),
ZX_VM_CAN_MAP_READ | ZX_VM_CAN_MAP_WRITE | ZX_VM_CAN_MAP_SPECIFIC, 0,
Size, &Data->Vmar, &Data->VmarBase);
if (UNLIKELY(Status != ZX_OK)) {
if (Status != ZX_ERR_NO_MEMORY || !AllowNoMem)
dieOnError(Status, "zx_vmar_allocate", Size);
return nullptr;
}
return reinterpret_cast<void *>(Data->VmarBase);
}
void *map(void *Addr, uptr Size, const char *Name, uptr Flags,
MapPlatformData *Data) {
DCHECK_EQ(Size % getPageSizeCached(), 0);
const bool AllowNoMem = !!(Flags & MAP_ALLOWNOMEM);
// For MAP_NOACCESS, just allocate a Vmar and return.
if (Flags & MAP_NOACCESS)
return allocateVmar(Size, Data, AllowNoMem);
const zx_handle_t Vmar = (Data && Data->Vmar != ZX_HANDLE_INVALID)
? Data->Vmar
: _zx_vmar_root_self();
zx_status_t Status;
zx_handle_t Vmo;
uint64_t VmoSize = 0;
if (Data && Data->Vmo != ZX_HANDLE_INVALID) {
// If a Vmo was specified, it's a resize operation.
CHECK(Addr);
DCHECK(Flags & MAP_RESIZABLE);
Vmo = Data->Vmo;
VmoSize = Data->VmoSize;
Status = _zx_vmo_set_size(Vmo, VmoSize + Size);
if (Status != ZX_OK) {
if (Status != ZX_ERR_NO_MEMORY || !AllowNoMem)
dieOnError(Status, "zx_vmo_set_size", VmoSize + Size);
return nullptr;
}
} else {
// Otherwise, create a Vmo and set its name.
Status = _zx_vmo_create(Size, ZX_VMO_RESIZABLE, &Vmo);
if (UNLIKELY(Status != ZX_OK)) {
if (Status != ZX_ERR_NO_MEMORY || !AllowNoMem)
dieOnError(Status, "zx_vmo_create", Size);
return nullptr;
}
_zx_object_set_property(Vmo, ZX_PROP_NAME, Name, strlen(Name));
}
uintptr_t P;
zx_vm_option_t MapFlags =
ZX_VM_PERM_READ | ZX_VM_PERM_WRITE | ZX_VM_ALLOW_FAULTS;
if (Addr)
DCHECK(Data);
const uint64_t Offset =
Addr ? reinterpret_cast<uintptr_t>(Addr) - Data->VmarBase : 0;
if (Offset)
MapFlags |= ZX_VM_SPECIFIC;
Status = _zx_vmar_map(Vmar, MapFlags, Offset, Vmo, VmoSize, Size, &P);
if (UNLIKELY(Status != ZX_OK)) {
if (Status != ZX_ERR_NO_MEMORY || !AllowNoMem)
dieOnError(Status, "zx_vmar_map", Size);
return nullptr;
}
if (Flags & MAP_PRECOMMIT) {
Status = _zx_vmar_op_range(Vmar, ZX_VMAR_OP_COMMIT, P, Size,
/*buffer=*/nullptr, /*buffer_size=*/0);
}
// No need to track the Vmo if we don't intend on resizing it. Close it.
if (Flags & MAP_RESIZABLE) {
DCHECK(Data);
if (Data->Vmo == ZX_HANDLE_INVALID)
Data->Vmo = Vmo;
else
DCHECK_EQ(Data->Vmo, Vmo);
} else {
CHECK_EQ(_zx_handle_close(Vmo), ZX_OK);
}
if (UNLIKELY(Status != ZX_OK)) {
if (Status != ZX_ERR_NO_MEMORY || !AllowNoMem)
dieOnError(Status, "zx_vmar_op_range", Size);
return nullptr;
}
if (Data)
Data->VmoSize += Size;
return reinterpret_cast<void *>(P);
}
void unmap(void *Addr, uptr Size, uptr Flags, MapPlatformData *Data) {
if (Flags & UNMAP_ALL) {
DCHECK_NE(Data, nullptr);
const zx_handle_t Vmar = Data->Vmar;
DCHECK_NE(Vmar, _zx_vmar_root_self());
// Destroying the vmar effectively unmaps the whole mapping.
CHECK_EQ(_zx_vmar_destroy(Vmar), ZX_OK);
CHECK_EQ(_zx_handle_close(Vmar), ZX_OK);
} else {
const zx_handle_t Vmar = (Data && Data->Vmar != ZX_HANDLE_INVALID)
? Data->Vmar
: _zx_vmar_root_self();
const zx_status_t Status =
_zx_vmar_unmap(Vmar, reinterpret_cast<uintptr_t>(Addr), Size);
if (UNLIKELY(Status != ZX_OK))
dieOnError(Status, "zx_vmar_unmap", Size);
}
if (Data) {
if (Data->Vmo != ZX_HANDLE_INVALID)
CHECK_EQ(_zx_handle_close(Data->Vmo), ZX_OK);
memset(Data, 0, sizeof(*Data));
}
}
void setMemoryPermission(UNUSED uptr Addr, UNUSED uptr Size, UNUSED uptr Flags,
UNUSED MapPlatformData *Data) {
const zx_vm_option_t Prot =
(Flags & MAP_NOACCESS) ? 0 : (ZX_VM_PERM_READ | ZX_VM_PERM_WRITE);
DCHECK(Data);
DCHECK_NE(Data->Vmar, ZX_HANDLE_INVALID);
const zx_status_t Status = _zx_vmar_protect(Data->Vmar, Prot, Addr, Size);
if (Status != ZX_OK)
dieOnError(Status, "zx_vmar_protect", Size);
}
void releasePagesToOS(UNUSED uptr BaseAddress, uptr Offset, uptr Size,
MapPlatformData *Data) {
// TODO: DCHECK the BaseAddress is consistent with the data in
// MapPlatformData.
DCHECK(Data);
DCHECK_NE(Data->Vmar, ZX_HANDLE_INVALID);
DCHECK_NE(Data->Vmo, ZX_HANDLE_INVALID);
const zx_status_t Status =
_zx_vmo_op_range(Data->Vmo, ZX_VMO_OP_DECOMMIT, Offset, Size, NULL, 0);
CHECK_EQ(Status, ZX_OK);
}
const char *getEnv(const char *Name) { return getenv(Name); }
// Note: we need to flag these methods with __TA_NO_THREAD_SAFETY_ANALYSIS
// because the Fuchsia implementation of sync_mutex_t has clang thread safety
// annotations. Were we to apply proper capability annotations to the top level
// HybridMutex class itself, they would not be needed. As it stands, the
// thread analysis thinks that we are locking the mutex and accidentally leaving
// it locked on the way out.
bool HybridMutex::tryLock() __TA_NO_THREAD_SAFETY_ANALYSIS {
// Size and alignment must be compatible between both types.
return sync_mutex_trylock(&M) == ZX_OK;
}
void HybridMutex::lockSlow() __TA_NO_THREAD_SAFETY_ANALYSIS {
sync_mutex_lock(&M);
}
void HybridMutex::unlock() __TA_NO_THREAD_SAFETY_ANALYSIS {
sync_mutex_unlock(&M);
}
void HybridMutex::assertHeldImpl() __TA_NO_THREAD_SAFETY_ANALYSIS {}
u64 getMonotonicTime() { return _zx_clock_get_monotonic(); }
u64 getMonotonicTimeFast() { return _zx_clock_get_monotonic(); }
u32 getNumberOfCPUs() { return _zx_system_get_num_cpus(); }
u32 getThreadID() { return 0; }
bool getRandom(void *Buffer, uptr Length, UNUSED bool Blocking) {
static_assert(MaxRandomLength <= ZX_CPRNG_DRAW_MAX_LEN, "");
if (UNLIKELY(!Buffer || !Length || Length > MaxRandomLength))
return false;
_zx_cprng_draw(Buffer, Length);
return true;
}
void outputRaw(const char *Buffer) {
__sanitizer_log_write(Buffer, strlen(Buffer));
}
void setAbortMessage(const char *Message) {}
} // namespace scudo
#endif // SCUDO_FUCHSIA
|
