1 /*
2  * Copyright (C) 2005 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "hw-Parcel"
18 //#define LOG_NDEBUG 0
19 
20 #include <errno.h>
21 #include <fcntl.h>
22 #include <inttypes.h>
23 #include <pthread.h>
24 #include <stdint.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <sys/mman.h>
28 #include <sys/stat.h>
29 #include <sys/types.h>
30 #include <sys/resource.h>
31 #include <unistd.h>
32 
33 #include <hwbinder/Binder.h>
34 #include <hwbinder/BpHwBinder.h>
35 #include <hwbinder/IPCThreadState.h>
36 #include <hwbinder/Parcel.h>
37 #include <hwbinder/ProcessState.h>
38 
39 #include <cutils/ashmem.h>
40 #include <utils/Log.h>
41 #include <utils/misc.h>
42 #include <utils/String8.h>
43 #include <utils/String16.h>
44 
45 #include "binder_kernel.h"
46 #include <hwbinder/Static.h>
47 #include "TextOutput.h"
48 #include "Utils.h"
49 
50 #include <atomic>
51 
52 #define LOG_REFS(...)
53 //#define LOG_REFS(...) ALOG(LOG_DEBUG, LOG_TAG, __VA_ARGS__)
54 #define LOG_ALLOC(...)
55 //#define LOG_ALLOC(...) ALOG(LOG_DEBUG, LOG_TAG, __VA_ARGS__)
56 #define LOG_BUFFER(...)
57 // #define LOG_BUFFER(...) ALOG(LOG_DEBUG, LOG_TAG, __VA_ARGS__)
58 
59 // ---------------------------------------------------------------------------
60 
61 // This macro should never be used at runtime, as a too large value
62 // of s could cause an integer overflow. Instead, you should always
63 // use the wrapper function pad_size()
64 #define PAD_SIZE_UNSAFE(s) (((s)+3)&~3)
65 
pad_size(size_t s)66 static size_t pad_size(size_t s) {
67     if (s > (std::numeric_limits<size_t>::max() - 3)) {
68         LOG_ALWAYS_FATAL("pad size too big %zu", s);
69     }
70     return PAD_SIZE_UNSAFE(s);
71 }
72 
73 // Note: must be kept in sync with android/os/StrictMode.java's PENALTY_GATHER
74 #define STRICT_MODE_PENALTY_GATHER (0x40 << 16)
75 
76 namespace android {
77 namespace hardware {
78 
79 static std::atomic<size_t> gParcelGlobalAllocCount;
80 static std::atomic<size_t> gParcelGlobalAllocSize;
81 
82 static size_t gMaxFds = 0;
83 
acquire_binder_object(const sp<ProcessState> & proc,const flat_binder_object & obj,const void * who)84 void acquire_binder_object(const sp<ProcessState>& proc,
85     const flat_binder_object& obj, const void* who)
86 {
87     switch (obj.hdr.type) {
88         case BINDER_TYPE_BINDER:
89             if (obj.binder) {
90                 LOG_REFS("Parcel %p acquiring reference on local %llu", who, obj.cookie);
91                 reinterpret_cast<IBinder*>(obj.cookie)->incStrong(who);
92             }
93             return;
94         case BINDER_TYPE_WEAK_BINDER:
95             if (obj.binder)
96                 reinterpret_cast<RefBase::weakref_type*>(obj.binder)->incWeak(who);
97             return;
98         case BINDER_TYPE_HANDLE: {
99             const sp<IBinder> b = proc->getStrongProxyForHandle(obj.handle);
100             if (b != nullptr) {
101                 LOG_REFS("Parcel %p acquiring reference on remote %p", who, b.get());
102                 b->incStrong(who);
103             }
104             return;
105         }
106         case BINDER_TYPE_WEAK_HANDLE: {
107             const wp<IBinder> b = proc->getWeakProxyForHandle(obj.handle);
108             if (b != nullptr) b.get_refs()->incWeak(who);
109             return;
110         }
111     }
112 
113     ALOGD("Invalid object type 0x%08x", obj.hdr.type);
114 }
115 
acquire_object(const sp<ProcessState> & proc,const binder_object_header & obj,const void * who)116 void acquire_object(const sp<ProcessState>& proc, const binder_object_header& obj,
117         const void *who) {
118     switch (obj.type) {
119         case BINDER_TYPE_BINDER:
120         case BINDER_TYPE_WEAK_BINDER:
121         case BINDER_TYPE_HANDLE:
122         case BINDER_TYPE_WEAK_HANDLE: {
123             const flat_binder_object& fbo = reinterpret_cast<const flat_binder_object&>(obj);
124             acquire_binder_object(proc, fbo, who);
125             break;
126         }
127     }
128 }
129 
release_object(const sp<ProcessState> & proc,const flat_binder_object & obj,const void * who)130 void release_object(const sp<ProcessState>& proc,
131     const flat_binder_object& obj, const void* who)
132 {
133     switch (obj.hdr.type) {
134         case BINDER_TYPE_BINDER:
135             if (obj.binder) {
136                 LOG_REFS("Parcel %p releasing reference on local %llu", who, obj.cookie);
137                 reinterpret_cast<IBinder*>(obj.cookie)->decStrong(who);
138             }
139             return;
140         case BINDER_TYPE_WEAK_BINDER:
141             if (obj.binder)
142                 reinterpret_cast<RefBase::weakref_type*>(obj.binder)->decWeak(who);
143             return;
144         case BINDER_TYPE_HANDLE: {
145             const sp<IBinder> b = proc->getStrongProxyForHandle(obj.handle);
146             if (b != nullptr) {
147                 LOG_REFS("Parcel %p releasing reference on remote %p", who, b.get());
148                 b->decStrong(who);
149             }
150             return;
151         }
152         case BINDER_TYPE_WEAK_HANDLE: {
153             const wp<IBinder> b = proc->getWeakProxyForHandle(obj.handle);
154             if (b != nullptr) b.get_refs()->decWeak(who);
155             return;
156         }
157         case BINDER_TYPE_FD: {
158             if (obj.cookie != 0) { // owned
159                 close(obj.handle);
160             }
161             return;
162         }
163         case BINDER_TYPE_PTR: {
164             // The relevant buffer is part of the transaction buffer and will be freed that way
165             return;
166         }
167         case BINDER_TYPE_FDA: {
168             // The enclosed file descriptors are closed in the kernel
169             return;
170         }
171     }
172 
173     ALOGE("Invalid object type 0x%08x", obj.hdr.type);
174 }
175 
finish_flatten_binder(const sp<IBinder> &,const flat_binder_object & flat,Parcel * out)176 inline static status_t finish_flatten_binder(
177     const sp<IBinder>& /*binder*/, const flat_binder_object& flat, Parcel* out)
178 {
179     return out->writeObject(flat);
180 }
181 
flatten_binder(const sp<ProcessState> &,const sp<IBinder> & binder,Parcel * out)182 status_t flatten_binder(const sp<ProcessState>& /*proc*/,
183     const sp<IBinder>& binder, Parcel* out)
184 {
185     flat_binder_object obj = {};
186 
187     if (binder != nullptr) {
188         BHwBinder *local = binder->localBinder();
189         if (!local) {
190             BpHwBinder *proxy = binder->remoteBinder();
191             if (proxy == nullptr) {
192                 ALOGE("null proxy");
193             }
194             const int32_t handle = proxy ? proxy->handle() : 0;
195             obj.hdr.type = BINDER_TYPE_HANDLE;
196             obj.flags = FLAT_BINDER_FLAG_ACCEPTS_FDS;
197             obj.binder = 0; /* Don't pass uninitialized stack data to a remote process */
198             obj.handle = handle;
199             obj.cookie = 0;
200         } else {
201             // Get policy and convert it
202             int policy = local->getMinSchedulingPolicy();
203             int priority = local->getMinSchedulingPriority();
204 
205             obj.flags = priority & FLAT_BINDER_FLAG_PRIORITY_MASK;
206             obj.flags |= FLAT_BINDER_FLAG_ACCEPTS_FDS | FLAT_BINDER_FLAG_INHERIT_RT;
207             obj.flags |= (policy & 3) << FLAT_BINDER_FLAG_SCHED_POLICY_SHIFT;
208             if (local->isRequestingSid()) {
209                 obj.flags |= FLAT_BINDER_FLAG_TXN_SECURITY_CTX;
210             }
211             obj.hdr.type = BINDER_TYPE_BINDER;
212             obj.binder = reinterpret_cast<uintptr_t>(local->getWeakRefs());
213             obj.cookie = reinterpret_cast<uintptr_t>(local);
214         }
215     } else {
216         obj.hdr.type = BINDER_TYPE_BINDER;
217         obj.binder = 0;
218         obj.cookie = 0;
219     }
220 
221     return finish_flatten_binder(binder, obj, out);
222 }
223 
finish_unflatten_binder(BpHwBinder *,const flat_binder_object &,const Parcel &)224 inline static status_t finish_unflatten_binder(
225     BpHwBinder* /*proxy*/, const flat_binder_object& /*flat*/,
226     const Parcel& /*in*/)
227 {
228     return NO_ERROR;
229 }
230 
unflatten_binder(const sp<ProcessState> & proc,const Parcel & in,sp<IBinder> * out)231 status_t unflatten_binder(const sp<ProcessState>& proc,
232     const Parcel& in, sp<IBinder>* out)
233 {
234     const flat_binder_object* flat = in.readObject<flat_binder_object>();
235 
236     if (flat) {
237         switch (flat->hdr.type) {
238             case BINDER_TYPE_BINDER:
239                 *out = reinterpret_cast<IBinder*>(flat->cookie);
240                 return finish_unflatten_binder(nullptr, *flat, in);
241             case BINDER_TYPE_HANDLE:
242                 *out = proc->getStrongProxyForHandle(flat->handle);
243                 return finish_unflatten_binder(
244                     static_cast<BpHwBinder*>(out->get()), *flat, in);
245         }
246     }
247     return BAD_TYPE;
248 }
249 
250 // ---------------------------------------------------------------------------
251 
Parcel()252 Parcel::Parcel()
253 {
254     LOG_ALLOC("Parcel %p: constructing", this);
255     initState();
256 }
257 
~Parcel()258 Parcel::~Parcel()
259 {
260     freeDataNoInit();
261     LOG_ALLOC("Parcel %p: destroyed", this);
262 }
263 
getGlobalAllocSize()264 size_t Parcel::getGlobalAllocSize() {
265     return gParcelGlobalAllocSize.load();
266 }
267 
getGlobalAllocCount()268 size_t Parcel::getGlobalAllocCount() {
269     return gParcelGlobalAllocCount.load();
270 }
271 
data() const272 const uint8_t* Parcel::data() const
273 {
274     return mData;
275 }
276 
dataSize() const277 size_t Parcel::dataSize() const
278 {
279     return (mDataSize > mDataPos ? mDataSize : mDataPos);
280 }
281 
dataAvail() const282 size_t Parcel::dataAvail() const
283 {
284     size_t result = dataSize() - dataPosition();
285     if (result > INT32_MAX) {
286         LOG_ALWAYS_FATAL("result too big: %zu", result);
287     }
288     return result;
289 }
290 
dataPosition() const291 size_t Parcel::dataPosition() const
292 {
293     return mDataPos;
294 }
295 
dataCapacity() const296 size_t Parcel::dataCapacity() const
297 {
298     return mDataCapacity;
299 }
300 
setDataSize(size_t size)301 status_t Parcel::setDataSize(size_t size)
302 {
303     if (size > INT32_MAX) {
304         // don't accept size_t values which may have come from an
305         // inadvertent conversion from a negative int.
306         return BAD_VALUE;
307     }
308 
309     status_t err;
310     err = continueWrite(size);
311     if (err == NO_ERROR) {
312         mDataSize = size;
313         ALOGV("setDataSize Setting data size of %p to %zu", this, mDataSize);
314     }
315     return err;
316 }
317 
setDataPosition(size_t pos) const318 void Parcel::setDataPosition(size_t pos) const
319 {
320     if (pos > INT32_MAX) {
321         // don't accept size_t values which may have come from an
322         // inadvertent conversion from a negative int.
323         LOG_ALWAYS_FATAL("pos too big: %zu", pos);
324     }
325 
326     mDataPos = pos;
327     mNextObjectHint = 0;
328 }
329 
setDataCapacity(size_t size)330 status_t Parcel::setDataCapacity(size_t size)
331 {
332     if (size > INT32_MAX) {
333         // don't accept size_t values which may have come from an
334         // inadvertent conversion from a negative int.
335         return BAD_VALUE;
336     }
337 
338     if (size > mDataCapacity) return continueWrite(size);
339     return NO_ERROR;
340 }
341 
markSensitive() const342 void Parcel::markSensitive() const
343 {
344     mDeallocZero = true;
345 }
346 
347 // Write RPC headers.  (previously just the interface token)
writeInterfaceToken(const char * interface)348 status_t Parcel::writeInterfaceToken(const char* interface)
349 {
350     // currently the interface identification token is just its name as a string
351     return writeCString(interface);
352 }
353 
enforceInterface(const char * interface) const354 bool Parcel::enforceInterface(const char* interface) const
355 {
356     const char* str = readCString();
357     if (str != nullptr && strcmp(str, interface) == 0) {
358         return true;
359     } else {
360         ALOGW("**** enforceInterface() expected '%s' but read '%s'",
361                 interface, (str ? str : "<empty string>"));
362         return false;
363     }
364 }
365 
objects() const366 const binder_size_t* Parcel::objects() const
367 {
368     return mObjects;
369 }
370 
objectsCount() const371 size_t Parcel::objectsCount() const
372 {
373     return mObjectsSize;
374 }
375 
errorCheck() const376 status_t Parcel::errorCheck() const
377 {
378     return mError;
379 }
380 
setError(status_t err)381 void Parcel::setError(status_t err)
382 {
383     mError = err;
384 }
385 
finishWrite(size_t len)386 status_t Parcel::finishWrite(size_t len)
387 {
388     if (len > INT32_MAX) {
389         // don't accept size_t values which may have come from an
390         // inadvertent conversion from a negative int.
391         return BAD_VALUE;
392     }
393 
394     //printf("Finish write of %d\n", len);
395     mDataPos += len;
396     ALOGV("finishWrite Setting data pos of %p to %zu", this, mDataPos);
397     if (mDataPos > mDataSize) {
398         mDataSize = mDataPos;
399         ALOGV("finishWrite Setting data size of %p to %zu", this, mDataSize);
400     }
401     //printf("New pos=%d, size=%d\n", mDataPos, mDataSize);
402     return NO_ERROR;
403 }
404 
writeUnpadded(const void * data,size_t len)405 status_t Parcel::writeUnpadded(const void* data, size_t len)
406 {
407     if (len > INT32_MAX) {
408         // don't accept size_t values which may have come from an
409         // inadvertent conversion from a negative int.
410         return BAD_VALUE;
411     }
412 
413     size_t end = mDataPos + len;
414     if (end < mDataPos) {
415         // integer overflow
416         return BAD_VALUE;
417     }
418 
419     if (end <= mDataCapacity) {
420 restart_write:
421         memcpy(mData+mDataPos, data, len);
422         return finishWrite(len);
423     }
424 
425     status_t err = growData(len);
426     if (err == NO_ERROR) goto restart_write;
427     return err;
428 }
429 
write(const void * data,size_t len)430 status_t Parcel::write(const void* data, size_t len)
431 {
432     if (len > INT32_MAX) {
433         // don't accept size_t values which may have come from an
434         // inadvertent conversion from a negative int.
435         return BAD_VALUE;
436     }
437 
438     void* const d = writeInplace(len);
439     if (d) {
440         memcpy(d, data, len);
441         return NO_ERROR;
442     }
443     return mError;
444 }
445 
writeInplace(size_t len)446 void* Parcel::writeInplace(size_t len)
447 {
448     if (len > INT32_MAX) {
449         // don't accept size_t values which may have come from an
450         // inadvertent conversion from a negative int.
451         return nullptr;
452     }
453 
454     const size_t padded = pad_size(len);
455 
456     // validate for integer overflow
457     if (mDataPos+padded < mDataPos) {
458         return nullptr;
459     }
460 
461     if ((mDataPos+padded) <= mDataCapacity) {
462 restart_write:
463         //printf("Writing %ld bytes, padded to %ld\n", len, padded);
464         uint8_t* const data = mData+mDataPos;
465 
466         // Need to pad at end?
467         if (padded != len) {
468 #if BYTE_ORDER == BIG_ENDIAN
469             static const uint32_t mask[4] = {
470                 0x00000000, 0xffffff00, 0xffff0000, 0xff000000
471             };
472 #endif
473 #if BYTE_ORDER == LITTLE_ENDIAN
474             static const uint32_t mask[4] = {
475                 0x00000000, 0x00ffffff, 0x0000ffff, 0x000000ff
476             };
477 #endif
478             //printf("Applying pad mask: %p to %p\n", (void*)mask[padded-len],
479             //    *reinterpret_cast<void**>(data+padded-4));
480             *reinterpret_cast<uint32_t*>(data+padded-4) &= mask[padded-len];
481         }
482 
483         finishWrite(padded);
484         return data;
485     }
486 
487     status_t err = growData(padded);
488     if (err == NO_ERROR) goto restart_write;
489     return nullptr;
490 }
491 
writeInt8(int8_t val)492 status_t Parcel::writeInt8(int8_t val)
493 {
494     return write(&val, sizeof(val));
495 }
496 
writeUint8(uint8_t val)497 status_t Parcel::writeUint8(uint8_t val)
498 {
499     return write(&val, sizeof(val));
500 }
501 
writeInt16(int16_t val)502 status_t Parcel::writeInt16(int16_t val)
503 {
504     return write(&val, sizeof(val));
505 }
506 
writeUint16(uint16_t val)507 status_t Parcel::writeUint16(uint16_t val)
508 {
509     return write(&val, sizeof(val));
510 }
511 
writeInt32(int32_t val)512 status_t Parcel::writeInt32(int32_t val)
513 {
514     return writeAligned(val);
515 }
516 
writeUint32(uint32_t val)517 status_t Parcel::writeUint32(uint32_t val)
518 {
519     return writeAligned(val);
520 }
521 
writeBool(bool val)522 status_t Parcel::writeBool(bool val)
523 {
524     return writeInt8(int8_t(val));
525 }
writeInt64(int64_t val)526 status_t Parcel::writeInt64(int64_t val)
527 {
528     return writeAligned(val);
529 }
530 
writeUint64(uint64_t val)531 status_t Parcel::writeUint64(uint64_t val)
532 {
533     return writeAligned(val);
534 }
535 
writePointer(uintptr_t val)536 status_t Parcel::writePointer(uintptr_t val)
537 {
538     return writeAligned<binder_uintptr_t>(val);
539 }
540 
writeFloat(float val)541 status_t Parcel::writeFloat(float val)
542 {
543     return writeAligned(val);
544 }
545 
546 #if defined(__mips__) && defined(__mips_hard_float)
547 
writeDouble(double val)548 status_t Parcel::writeDouble(double val)
549 {
550     union {
551         double d;
552         unsigned long long ll;
553     } u;
554     u.d = val;
555     return writeAligned(u.ll);
556 }
557 
558 #else
559 
writeDouble(double val)560 status_t Parcel::writeDouble(double val)
561 {
562     return writeAligned(val);
563 }
564 
565 #endif
566 
writeCString(const char * str)567 status_t Parcel::writeCString(const char* str)
568 {
569     return write(str, strlen(str)+1);
570 }
writeString16(const std::unique_ptr<String16> & str)571 status_t Parcel::writeString16(const std::unique_ptr<String16>& str)
572 {
573     if (!str) {
574         return writeInt32(-1);
575     }
576 
577     return writeString16(*str);
578 }
579 
writeString16(const String16 & str)580 status_t Parcel::writeString16(const String16& str)
581 {
582     return writeString16(str.c_str(), str.size());
583 }
584 
writeString16(const char16_t * str,size_t len)585 status_t Parcel::writeString16(const char16_t* str, size_t len)
586 {
587     if (str == nullptr) return writeInt32(-1);
588 
589     status_t err = writeInt32(len);
590     if (err == NO_ERROR) {
591         len *= sizeof(char16_t);
592         uint8_t* data = (uint8_t*)writeInplace(len+sizeof(char16_t));
593         if (data) {
594             memcpy(data, str, len);
595             *reinterpret_cast<char16_t*>(data+len) = 0;
596             return NO_ERROR;
597         }
598         err = mError;
599     }
600     return err;
601 }
writeStrongBinder(const sp<IBinder> & val)602 status_t Parcel::writeStrongBinder(const sp<IBinder>& val)
603 {
604     return flatten_binder(ProcessState::self(), val, this);
605 }
606 
607 template <typename T>
writeObject(const T & val)608 status_t Parcel::writeObject(const T& val)
609 {
610     const bool enoughData = (mDataPos+sizeof(val)) <= mDataCapacity;
611     const bool enoughObjects = mObjectsSize < mObjectsCapacity;
612     if (enoughData && enoughObjects) {
613 restart_write:
614         *reinterpret_cast<T*>(mData+mDataPos) = val;
615 
616         const binder_object_header* hdr = reinterpret_cast<binder_object_header*>(mData+mDataPos);
617         switch (hdr->type) {
618             case BINDER_TYPE_BINDER:
619             case BINDER_TYPE_WEAK_BINDER:
620             case BINDER_TYPE_HANDLE:
621             case BINDER_TYPE_WEAK_HANDLE: {
622                 const flat_binder_object *fbo = reinterpret_cast<const flat_binder_object*>(hdr);
623                 if (fbo->binder != 0) {
624                     mObjects[mObjectsSize++] = mDataPos;
625                     acquire_binder_object(ProcessState::self(), *fbo, this);
626                 }
627                 break;
628             }
629             case BINDER_TYPE_FD: {
630                 // remember if it's a file descriptor
631                 if (!mAllowFds) {
632                     // fail before modifying our object index
633                     return FDS_NOT_ALLOWED;
634                 }
635                 mHasFds = mFdsKnown = true;
636                 mObjects[mObjectsSize++] = mDataPos;
637                 break;
638             }
639             case BINDER_TYPE_FDA:
640                 mObjects[mObjectsSize++] = mDataPos;
641                 break;
642             case BINDER_TYPE_PTR: {
643                 const binder_buffer_object *buffer_obj = reinterpret_cast<
644                     const binder_buffer_object*>(hdr);
645                 if ((void *)buffer_obj->buffer != nullptr) {
646                     mObjects[mObjectsSize++] = mDataPos;
647                 }
648                 break;
649             }
650             default: {
651                 ALOGE("writeObject: unknown type %d", hdr->type);
652                 break;
653             }
654         }
655         return finishWrite(sizeof(val));
656     }
657 
658     if (!enoughData) {
659         const status_t err = growData(sizeof(val));
660         if (err != NO_ERROR) return err;
661     }
662     if (!enoughObjects) {
663         if (mObjectsSize > SIZE_MAX - 2) return NO_MEMORY; // overflow
664         if (mObjectsSize + 2 > SIZE_MAX / 3) return NO_MEMORY; // overflow
665         size_t newSize = ((mObjectsSize+2)*3)/2;
666         if (newSize > SIZE_MAX / sizeof(binder_size_t)) return NO_MEMORY; // overflow
667         binder_size_t* objects = (binder_size_t*)realloc(mObjects, newSize*sizeof(binder_size_t));
668         if (objects == nullptr) return NO_MEMORY;
669         mObjects = objects;
670         mObjectsCapacity = newSize;
671     }
672 
673     goto restart_write;
674 }
675 
676 template status_t Parcel::writeObject<flat_binder_object>(const flat_binder_object& val);
677 template status_t Parcel::writeObject<binder_fd_object>(const binder_fd_object& val);
678 template status_t Parcel::writeObject<binder_buffer_object>(const binder_buffer_object& val);
679 template status_t Parcel::writeObject<binder_fd_array_object>(const binder_fd_array_object& val);
680 
validateBufferChild(size_t child_buffer_handle,size_t child_offset) const681 bool Parcel::validateBufferChild(size_t child_buffer_handle,
682                                  size_t child_offset) const {
683     if (child_buffer_handle >= mObjectsSize)
684         return false;
685     binder_buffer_object *child = reinterpret_cast<binder_buffer_object*>
686             (mData + mObjects[child_buffer_handle]);
687     if (child->hdr.type != BINDER_TYPE_PTR || child_offset > child->length) {
688         // Parent object not a buffer, or not large enough
689         LOG_BUFFER("writeEmbeddedReference found weird child. "
690                    "child_offset = %zu, child->length = %zu",
691                    child_offset, (size_t)child->length);
692         return false;
693     }
694     return true;
695 }
696 
validateBufferParent(size_t parent_buffer_handle,size_t parent_offset) const697 bool Parcel::validateBufferParent(size_t parent_buffer_handle,
698                                   size_t parent_offset) const {
699     if (parent_buffer_handle >= mObjectsSize)
700         return false;
701     binder_buffer_object *parent = reinterpret_cast<binder_buffer_object*>
702             (mData + mObjects[parent_buffer_handle]);
703     if (parent->hdr.type != BINDER_TYPE_PTR ||
704             sizeof(binder_uintptr_t) > parent->length ||
705             parent_offset > parent->length - sizeof(binder_uintptr_t)) {
706         // Parent object not a buffer, or not large enough
707         return false;
708     }
709     return true;
710 }
writeEmbeddedBuffer(const void * buffer,size_t length,size_t * handle,size_t parent_buffer_handle,size_t parent_offset)711 status_t Parcel::writeEmbeddedBuffer(
712         const void *buffer, size_t length, size_t *handle,
713         size_t parent_buffer_handle, size_t parent_offset) {
714     LOG_BUFFER("writeEmbeddedBuffer(%p, %zu, parent = (%zu, %zu)) -> %zu",
715         buffer, length, parent_buffer_handle,
716          parent_offset, mObjectsSize);
717     if(!validateBufferParent(parent_buffer_handle, parent_offset))
718         return BAD_VALUE;
719     binder_buffer_object obj = {
720         .hdr = { .type = BINDER_TYPE_PTR },
721         .flags = BINDER_BUFFER_FLAG_HAS_PARENT,
722         .buffer = reinterpret_cast<binder_uintptr_t>(buffer),
723         .length = length,
724         .parent = parent_buffer_handle,
725         .parent_offset = parent_offset,
726     };
727     if (handle != nullptr) {
728         // We use an index into mObjects as a handle
729         *handle = mObjectsSize;
730     }
731     return writeObject(obj);
732 }
733 
writeBuffer(const void * buffer,size_t length,size_t * handle)734 status_t Parcel::writeBuffer(const void *buffer, size_t length, size_t *handle)
735 {
736     LOG_BUFFER("writeBuffer(%p, %zu) -> %zu",
737         buffer, length, mObjectsSize);
738     binder_buffer_object obj {
739         .hdr = { .type = BINDER_TYPE_PTR },
740         .flags = 0,
741         .buffer = reinterpret_cast<binder_uintptr_t>(buffer),
742         .length = length,
743     };
744     if (handle != nullptr) {
745         // We use an index into mObjects as a handle
746         *handle = mObjectsSize;
747     }
748     return writeObject(obj);
749 }
750 
clearCache() const751 void Parcel::clearCache() const {
752     LOG_BUFFER("clearing cache.");
753     mBufCachePos = 0;
754     mBufCache.clear();
755 }
756 
updateCache() const757 void Parcel::updateCache() const {
758     if(mBufCachePos == mObjectsSize)
759         return;
760     LOG_BUFFER("updating cache from %zu to %zu", mBufCachePos, mObjectsSize);
761     for(size_t i = mBufCachePos; i < mObjectsSize; i++) {
762         binder_size_t dataPos = mObjects[i];
763         binder_buffer_object *obj =
764             reinterpret_cast<binder_buffer_object*>(mData+dataPos);
765         if(obj->hdr.type != BINDER_TYPE_PTR)
766             continue;
767         BufferInfo ifo;
768         ifo.index = i;
769         ifo.buffer = obj->buffer;
770         ifo.bufend = obj->buffer + obj->length;
771         mBufCache.push_back(ifo);
772     }
773     mBufCachePos = mObjectsSize;
774 }
775 
776 /* O(n) (n=#buffers) to find a buffer that contains the given addr */
findBuffer(const void * ptr,size_t length,bool * found,size_t * handle,size_t * offset) const777 status_t Parcel::findBuffer(const void *ptr, size_t length, bool *found,
778                         size_t *handle, size_t *offset) const {
779     if(found == nullptr)
780         return UNKNOWN_ERROR;
781     updateCache();
782     binder_uintptr_t ptrVal = reinterpret_cast<binder_uintptr_t>(ptr);
783     // true if the pointer is in some buffer, but the length is too big
784     // so that ptr + length doesn't fit into the buffer.
785     bool suspectRejectBadPointer = false;
786     LOG_BUFFER("findBuffer examining %zu objects.", mObjectsSize);
787     for(auto entry = mBufCache.rbegin(); entry != mBufCache.rend(); ++entry ) {
788         if(entry->buffer <= ptrVal && ptrVal < entry->bufend) {
789             // might have found it.
790             if(ptrVal + length <= entry->bufend) {
791                 *found = true;
792                 if(handle != nullptr) *handle = entry->index;
793                 if(offset != nullptr) *offset = ptrVal - entry->buffer;
794                 LOG_BUFFER("    findBuffer has a match at %zu!", entry->index);
795                 return OK;
796             } else {
797                 suspectRejectBadPointer = true;
798             }
799         }
800     }
801     LOG_BUFFER("findBuffer did not find for ptr = %p.", ptr);
802     *found = false;
803     return suspectRejectBadPointer ? BAD_VALUE : OK;
804 }
805 
806 /* findBuffer with the assumption that ptr = .buffer (so it points to top
807  * of the buffer, aka offset 0).
808  *  */
quickFindBuffer(const void * ptr,size_t * handle) const809 status_t Parcel::quickFindBuffer(const void *ptr, size_t *handle) const {
810     updateCache();
811     binder_uintptr_t ptrVal = reinterpret_cast<binder_uintptr_t>(ptr);
812     LOG_BUFFER("quickFindBuffer examining %zu objects.", mObjectsSize);
813     for(auto entry = mBufCache.rbegin(); entry != mBufCache.rend(); ++entry ) {
814         if(entry->buffer == ptrVal) {
815             if(handle != nullptr) *handle = entry->index;
816             return OK;
817         }
818     }
819     LOG_BUFFER("quickFindBuffer did not find for ptr = %p.", ptr);
820     return NO_INIT;
821 }
822 
writeNativeHandleNoDup(const native_handle_t * handle,bool embedded,size_t parent_buffer_handle,size_t parent_offset)823 status_t Parcel::writeNativeHandleNoDup(const native_handle_t *handle,
824                                         bool embedded,
825                                         size_t parent_buffer_handle,
826                                         size_t parent_offset)
827 {
828     size_t buffer_handle;
829     status_t status = OK;
830 
831     if (handle == nullptr) {
832         status = writeUint64(0);
833         return status;
834     }
835 
836     size_t native_handle_size = sizeof(native_handle_t)
837                 + handle->numFds * sizeof(int) + handle->numInts * sizeof(int);
838     writeUint64(native_handle_size);
839 
840     if (embedded) {
841         status = writeEmbeddedBuffer((void*) handle,
842                 native_handle_size, &buffer_handle,
843                 parent_buffer_handle, parent_offset);
844     } else {
845         status = writeBuffer((void*) handle, native_handle_size, &buffer_handle);
846     }
847 
848     if (status != OK) {
849         return status;
850     }
851 
852     struct binder_fd_array_object fd_array {
853         .hdr = { .type = BINDER_TYPE_FDA },
854         .num_fds = static_cast<binder_size_t>(handle->numFds),
855         .parent = buffer_handle,
856         .parent_offset = offsetof(native_handle_t, data),
857     };
858 
859     return writeObject(fd_array);
860 }
861 
writeNativeHandleNoDup(const native_handle_t * handle)862 status_t Parcel::writeNativeHandleNoDup(const native_handle_t *handle)
863 {
864     return writeNativeHandleNoDup(handle, false /* embedded */);
865 }
866 
writeEmbeddedNativeHandle(const native_handle_t * handle,size_t parent_buffer_handle,size_t parent_offset)867 status_t Parcel::writeEmbeddedNativeHandle(const native_handle_t *handle,
868                                            size_t parent_buffer_handle,
869                                            size_t parent_offset)
870 {
871     return writeNativeHandleNoDup(handle, true /* embedded */,
872                                   parent_buffer_handle, parent_offset);
873 }
874 
read(void * outData,size_t len) const875 status_t Parcel::read(void* outData, size_t len) const
876 {
877     if (len > INT32_MAX) {
878         // don't accept size_t values which may have come from an
879         // inadvertent conversion from a negative int.
880         return BAD_VALUE;
881     }
882 
883     if ((mDataPos+pad_size(len)) >= mDataPos && (mDataPos+pad_size(len)) <= mDataSize
884             && len <= pad_size(len)) {
885         memcpy(outData, mData+mDataPos, len);
886         mDataPos += pad_size(len);
887         ALOGV("read Setting data pos of %p to %zu", this, mDataPos);
888         return NO_ERROR;
889     }
890     return NOT_ENOUGH_DATA;
891 }
892 
readInplace(size_t len) const893 const void* Parcel::readInplace(size_t len) const
894 {
895     if (len > INT32_MAX) {
896         // don't accept size_t values which may have come from an
897         // inadvertent conversion from a negative int.
898         return nullptr;
899     }
900 
901     if ((mDataPos+pad_size(len)) >= mDataPos && (mDataPos+pad_size(len)) <= mDataSize
902             && len <= pad_size(len)) {
903         const void* data = mData+mDataPos;
904         mDataPos += pad_size(len);
905         ALOGV("readInplace Setting data pos of %p to %zu", this, mDataPos);
906         return data;
907     }
908     return nullptr;
909 }
910 
911 template<class T>
readAligned(T * pArg) const912 status_t Parcel::readAligned(T *pArg) const {
913     static_assert(PAD_SIZE_UNSAFE(sizeof(T)) == sizeof(T));
914 
915     if ((mDataPos+sizeof(T)) <= mDataSize) {
916         const void* data = mData+mDataPos;
917         mDataPos += sizeof(T);
918         *pArg =  *reinterpret_cast<const T*>(data);
919         return NO_ERROR;
920     } else {
921         return NOT_ENOUGH_DATA;
922     }
923 }
924 
925 template<class T>
readAligned() const926 T Parcel::readAligned() const {
927     T result;
928     if (readAligned(&result) != NO_ERROR) {
929         result = 0;
930     }
931 
932     return result;
933 }
934 
935 template<class T>
writeAligned(T val)936 status_t Parcel::writeAligned(T val) {
937     static_assert(PAD_SIZE_UNSAFE(sizeof(T)) == sizeof(T));
938 
939     if ((mDataPos+sizeof(val)) <= mDataCapacity) {
940 restart_write:
941         *reinterpret_cast<T*>(mData+mDataPos) = val;
942         return finishWrite(sizeof(val));
943     }
944 
945     status_t err = growData(sizeof(val));
946     if (err == NO_ERROR) goto restart_write;
947     return err;
948 }
949 
readInt8(int8_t * pArg) const950 status_t Parcel::readInt8(int8_t *pArg) const
951 {
952     return read(pArg, sizeof(*pArg));
953 }
954 
readUint8(uint8_t * pArg) const955 status_t Parcel::readUint8(uint8_t *pArg) const
956 {
957     return read(pArg, sizeof(*pArg));
958 }
959 
readInt16(int16_t * pArg) const960 status_t Parcel::readInt16(int16_t *pArg) const
961 {
962     return read(pArg, sizeof(*pArg));
963 }
964 
readUint16(uint16_t * pArg) const965 status_t Parcel::readUint16(uint16_t *pArg) const
966 {
967     return read(pArg, sizeof(*pArg));
968 }
969 
readInt32(int32_t * pArg) const970 status_t Parcel::readInt32(int32_t *pArg) const
971 {
972     return readAligned(pArg);
973 }
974 
readInt32() const975 int32_t Parcel::readInt32() const
976 {
977     return readAligned<int32_t>();
978 }
979 
readUint32(uint32_t * pArg) const980 status_t Parcel::readUint32(uint32_t *pArg) const
981 {
982     return readAligned(pArg);
983 }
984 
readUint32() const985 uint32_t Parcel::readUint32() const
986 {
987     return readAligned<uint32_t>();
988 }
989 
readInt64(int64_t * pArg) const990 status_t Parcel::readInt64(int64_t *pArg) const
991 {
992     return readAligned(pArg);
993 }
994 
readInt64() const995 int64_t Parcel::readInt64() const
996 {
997     return readAligned<int64_t>();
998 }
999 
readUint64(uint64_t * pArg) const1000 status_t Parcel::readUint64(uint64_t *pArg) const
1001 {
1002     return readAligned(pArg);
1003 }
1004 
readUint64() const1005 uint64_t Parcel::readUint64() const
1006 {
1007     return readAligned<uint64_t>();
1008 }
1009 
readPointer(uintptr_t * pArg) const1010 status_t Parcel::readPointer(uintptr_t *pArg) const
1011 {
1012     status_t ret;
1013     binder_uintptr_t ptr;
1014     ret = readAligned(&ptr);
1015     if (!ret)
1016         *pArg = ptr;
1017     return ret;
1018 }
1019 
readPointer() const1020 uintptr_t Parcel::readPointer() const
1021 {
1022     return readAligned<binder_uintptr_t>();
1023 }
1024 
1025 
readFloat(float * pArg) const1026 status_t Parcel::readFloat(float *pArg) const
1027 {
1028     return readAligned(pArg);
1029 }
1030 
1031 
readFloat() const1032 float Parcel::readFloat() const
1033 {
1034     return readAligned<float>();
1035 }
1036 
1037 #if defined(__mips__) && defined(__mips_hard_float)
1038 
readDouble(double * pArg) const1039 status_t Parcel::readDouble(double *pArg) const
1040 {
1041     union {
1042       double d;
1043       unsigned long long ll;
1044     } u;
1045     u.d = 0;
1046     status_t status;
1047     status = readAligned(&u.ll);
1048     *pArg = u.d;
1049     return status;
1050 }
1051 
readDouble() const1052 double Parcel::readDouble() const
1053 {
1054     union {
1055       double d;
1056       unsigned long long ll;
1057     } u;
1058     u.ll = readAligned<unsigned long long>();
1059     return u.d;
1060 }
1061 
1062 #else
1063 
readDouble(double * pArg) const1064 status_t Parcel::readDouble(double *pArg) const
1065 {
1066     return readAligned(pArg);
1067 }
1068 
readDouble() const1069 double Parcel::readDouble() const
1070 {
1071     return readAligned<double>();
1072 }
1073 
1074 #endif
1075 
readBool(bool * pArg) const1076 status_t Parcel::readBool(bool *pArg) const
1077 {
1078     int8_t tmp;
1079     status_t ret = readInt8(&tmp);
1080     *pArg = (tmp != 0);
1081     return ret;
1082 }
1083 
readBool() const1084 bool Parcel::readBool() const
1085 {
1086     int8_t tmp;
1087     status_t err = readInt8(&tmp);
1088 
1089     if (err != OK) {
1090         return 0;
1091     }
1092 
1093     return tmp != 0;
1094 }
1095 
readCString() const1096 const char* Parcel::readCString() const
1097 {
1098     if (mDataPos < mDataSize) {
1099         const size_t avail = mDataSize-mDataPos;
1100         const char* str = reinterpret_cast<const char*>(mData+mDataPos);
1101         // is the string's trailing NUL within the parcel's valid bounds?
1102         const char* eos = reinterpret_cast<const char*>(memchr(str, 0, avail));
1103         if (eos) {
1104             const size_t len = eos - str;
1105             mDataPos += pad_size(len+1);
1106             ALOGV("readCString Setting data pos of %p to %zu", this, mDataPos);
1107             return str;
1108         }
1109     }
1110     return nullptr;
1111 }
readString16() const1112 String16 Parcel::readString16() const
1113 {
1114     size_t len;
1115     const char16_t* str = readString16Inplace(&len);
1116     if (str) return String16(str, len);
1117     ALOGE("Reading a NULL string not supported here.");
1118     return String16();
1119 }
1120 
readString16(std::unique_ptr<String16> * pArg) const1121 status_t Parcel::readString16(std::unique_ptr<String16>* pArg) const
1122 {
1123     const int32_t start = dataPosition();
1124     int32_t size;
1125     status_t status = readInt32(&size);
1126     pArg->reset();
1127 
1128     if (status != OK || size < 0) {
1129         return status;
1130     }
1131 
1132     setDataPosition(start);
1133     pArg->reset(new (std::nothrow) String16());
1134 
1135     status = readString16(pArg->get());
1136 
1137     if (status != OK) {
1138         pArg->reset();
1139     }
1140 
1141     return status;
1142 }
1143 
readString16(String16 * pArg) const1144 status_t Parcel::readString16(String16* pArg) const
1145 {
1146     size_t len;
1147     const char16_t* str = readString16Inplace(&len);
1148     if (str) {
1149         pArg->setTo(str, len);
1150         return 0;
1151     } else {
1152         *pArg = String16();
1153         return UNEXPECTED_NULL;
1154     }
1155 }
1156 
readString16Inplace(size_t * outLen) const1157 const char16_t* Parcel::readString16Inplace(size_t* outLen) const
1158 {
1159     int32_t size = readInt32();
1160     // watch for potential int overflow from size+1
1161     if (size >= 0 && size < INT32_MAX) {
1162         *outLen = size;
1163         const char16_t* str = (const char16_t*)readInplace((size+1)*sizeof(char16_t));
1164         if (str != nullptr) {
1165             return str;
1166         }
1167     }
1168     *outLen = 0;
1169     return nullptr;
1170 }
readStrongBinder(sp<IBinder> * val) const1171 status_t Parcel::readStrongBinder(sp<IBinder>* val) const
1172 {
1173     status_t status = readNullableStrongBinder(val);
1174     if (status == OK && !val->get()) {
1175         status = UNEXPECTED_NULL;
1176     }
1177     return status;
1178 }
1179 
readNullableStrongBinder(sp<IBinder> * val) const1180 status_t Parcel::readNullableStrongBinder(sp<IBinder>* val) const
1181 {
1182     return unflatten_binder(ProcessState::self(), *this, val);
1183 }
1184 
readStrongBinder() const1185 sp<IBinder> Parcel::readStrongBinder() const
1186 {
1187     sp<IBinder> val;
1188     // Note that a lot of code in Android reads binders by hand with this
1189     // method, and that code has historically been ok with getting nullptr
1190     // back (while ignoring error codes).
1191     readNullableStrongBinder(&val);
1192     return val;
1193 }
1194 
1195 template<typename T>
readObject(size_t * objects_offset) const1196 const T* Parcel::readObject(size_t *objects_offset) const
1197 {
1198     const size_t DPOS = mDataPos;
1199     if (objects_offset != nullptr) {
1200         *objects_offset = 0;
1201     }
1202 
1203     if ((DPOS+sizeof(T)) <= mDataSize) {
1204         const T* obj = reinterpret_cast<const T*>(mData+DPOS);
1205         mDataPos = DPOS + sizeof(T);
1206         const binder_object_header *hdr = reinterpret_cast<const binder_object_header*>(obj);
1207         switch (hdr->type) {
1208             case BINDER_TYPE_BINDER:
1209             case BINDER_TYPE_WEAK_BINDER:
1210             case BINDER_TYPE_HANDLE:
1211             case BINDER_TYPE_WEAK_HANDLE: {
1212                 const flat_binder_object *flat_obj =
1213                     reinterpret_cast<const flat_binder_object*>(hdr);
1214                 if (flat_obj->cookie == 0 && flat_obj->binder == 0) {
1215                     // When transferring a NULL binder object, we don't write it into
1216                     // the object list, so we don't want to check for it when
1217                     // reading.
1218                     ALOGV("readObject Setting data pos of %p to %zu", this, mDataPos);
1219                     return obj;
1220                 }
1221                 break;
1222             }
1223             case BINDER_TYPE_FD:
1224             case BINDER_TYPE_FDA:
1225                 // fd (-arrays) must always appear in the meta-data list (eg touched by the kernel)
1226                 break;
1227             case BINDER_TYPE_PTR: {
1228                 const binder_buffer_object *buffer_obj =
1229                     reinterpret_cast<const binder_buffer_object*>(hdr);
1230                 if ((void *)buffer_obj->buffer == nullptr) {
1231                     // null pointers can be returned directly - they're not written in the
1232                     // object list. All non-null buffers must appear in the objects list.
1233                     return obj;
1234                 }
1235                 break;
1236             }
1237         }
1238         // Ensure that this object is valid...
1239         binder_size_t* const OBJS = mObjects;
1240         const size_t N = mObjectsSize;
1241         size_t opos = mNextObjectHint;
1242 
1243         if (N > 0) {
1244             ALOGV("Parcel %p looking for obj at %zu, hint=%zu",
1245                  this, DPOS, opos);
1246 
1247             // Start at the current hint position, looking for an object at
1248             // the current data position.
1249             if (opos < N) {
1250                 while (opos < (N-1) && OBJS[opos] < DPOS) {
1251                     opos++;
1252                 }
1253             } else {
1254                 opos = N-1;
1255             }
1256             if (OBJS[opos] == DPOS) {
1257                 // Found it!
1258                 ALOGV("Parcel %p found obj %zu at index %zu with forward search",
1259                      this, DPOS, opos);
1260                 mNextObjectHint = opos+1;
1261                 ALOGV("readObject Setting data pos of %p to %zu", this, mDataPos);
1262                 if (objects_offset != nullptr) {
1263                     *objects_offset = opos;
1264                 }
1265                 return obj;
1266             }
1267 
1268             // Look backwards for it...
1269             while (opos > 0 && OBJS[opos] > DPOS) {
1270                 opos--;
1271             }
1272             if (OBJS[opos] == DPOS) {
1273                 // Found it!
1274                 ALOGV("Parcel %p found obj %zu at index %zu with backward search",
1275                      this, DPOS, opos);
1276                 mNextObjectHint = opos+1;
1277                 ALOGV("readObject Setting data pos of %p to %zu", this, mDataPos);
1278                 if (objects_offset != nullptr) {
1279                     *objects_offset = opos;
1280                 }
1281                 return obj;
1282             }
1283         }
1284         ALOGW("Attempt to read object from Parcel %p at offset %zu that is not in the object list",
1285              this, DPOS);
1286     }
1287     return nullptr;
1288 }
1289 
1290 template const flat_binder_object* Parcel::readObject<flat_binder_object>(size_t *objects_offset) const;
1291 
1292 template const binder_fd_object* Parcel::readObject<binder_fd_object>(size_t *objects_offset) const;
1293 
1294 template const binder_buffer_object* Parcel::readObject<binder_buffer_object>(size_t *objects_offset) const;
1295 
1296 template const binder_fd_array_object* Parcel::readObject<binder_fd_array_object>(size_t *objects_offset) const;
1297 
verifyBufferObject(const binder_buffer_object * buffer_obj,size_t size,uint32_t flags,size_t parent,size_t parentOffset) const1298 bool Parcel::verifyBufferObject(const binder_buffer_object *buffer_obj,
1299                                 size_t size, uint32_t flags, size_t parent,
1300                                 size_t parentOffset) const {
1301     if (buffer_obj->length != size) {
1302         ALOGE("Buffer length %" PRIu64 " does not match expected size %zu.",
1303               static_cast<uint64_t>(buffer_obj->length), size);
1304         return false;
1305     }
1306 
1307     if (buffer_obj->flags != flags) {
1308         ALOGE("Buffer flags 0x%02X do not match expected flags 0x%02X.", buffer_obj->flags, flags);
1309         return false;
1310     }
1311 
1312     if (flags & BINDER_BUFFER_FLAG_HAS_PARENT) {
1313         if (buffer_obj->parent != parent) {
1314             ALOGE("Buffer parent %" PRIu64 " does not match expected parent %zu.",
1315                   static_cast<uint64_t>(buffer_obj->parent), parent);
1316             return false;
1317         }
1318         if (buffer_obj->parent_offset != parentOffset) {
1319             ALOGE("Buffer parent offset %" PRIu64 " does not match expected offset %zu.",
1320                   static_cast<uint64_t>(buffer_obj->parent_offset), parentOffset);
1321             return false;
1322         }
1323 
1324         // checked by kernel driver, but needed for fuzzer
1325         if (parent >= mObjectsSize) {
1326             ALOGE("Parent index %zu but only have %zu objects", parent, mObjectsSize);
1327             return false;
1328         }
1329 
1330         binder_buffer_object *parentBuffer =
1331             reinterpret_cast<binder_buffer_object*>(mData + mObjects[parent]);
1332         void* bufferInParent = *reinterpret_cast<void**>(
1333             reinterpret_cast<uint8_t*>(parentBuffer->buffer) + parentOffset);
1334         void* childBuffer = reinterpret_cast<void*>(buffer_obj->buffer);
1335 
1336         if (bufferInParent != childBuffer) {
1337               ALOGE("Buffer in parent %p differs from embedded buffer %p",
1338                     bufferInParent, childBuffer);
1339               android_errorWriteLog(0x534e4554, "179289794");
1340               return false;
1341         }
1342     }
1343 
1344     return true;
1345 }
1346 
readBuffer(size_t buffer_size,size_t * buffer_handle,uint32_t flags,size_t parent,size_t parentOffset,const void ** buffer_out) const1347 status_t Parcel::readBuffer(size_t buffer_size, size_t *buffer_handle,
1348                             uint32_t flags, size_t parent, size_t parentOffset,
1349                             const void **buffer_out) const {
1350 
1351     const binder_buffer_object* buffer_obj = readObject<binder_buffer_object>(buffer_handle);
1352 
1353     if (buffer_obj == nullptr || buffer_obj->hdr.type != BINDER_TYPE_PTR) {
1354         return BAD_VALUE;
1355     }
1356 
1357     if (!verifyBufferObject(buffer_obj, buffer_size, flags, parent, parentOffset)) {
1358         return BAD_VALUE;
1359     }
1360 
1361     // in read side, always use .buffer and .length.
1362     *buffer_out = reinterpret_cast<void*>(buffer_obj->buffer);
1363 
1364     return OK;
1365 }
1366 
readNullableBuffer(size_t buffer_size,size_t * buffer_handle,const void ** buffer_out) const1367 status_t Parcel::readNullableBuffer(size_t buffer_size, size_t *buffer_handle,
1368                                     const void **buffer_out) const
1369 {
1370     return readBuffer(buffer_size, buffer_handle,
1371                       0 /* flags */, 0 /* parent */, 0 /* parentOffset */,
1372                       buffer_out);
1373 }
1374 
readBuffer(size_t buffer_size,size_t * buffer_handle,const void ** buffer_out) const1375 status_t Parcel::readBuffer(size_t buffer_size, size_t *buffer_handle,
1376                             const void **buffer_out) const
1377 {
1378     status_t status = readNullableBuffer(buffer_size, buffer_handle, buffer_out);
1379     if (status == OK && *buffer_out == nullptr) {
1380         return UNEXPECTED_NULL;
1381     }
1382     return status;
1383 }
1384 
1385 
readEmbeddedBuffer(size_t buffer_size,size_t * buffer_handle,size_t parent_buffer_handle,size_t parent_offset,const void ** buffer_out) const1386 status_t Parcel::readEmbeddedBuffer(size_t buffer_size,
1387                                     size_t *buffer_handle,
1388                                     size_t parent_buffer_handle,
1389                                     size_t parent_offset,
1390                                     const void **buffer_out) const
1391 {
1392     status_t status = readNullableEmbeddedBuffer(buffer_size, buffer_handle,
1393                                                  parent_buffer_handle,
1394                                                  parent_offset, buffer_out);
1395     if (status == OK && *buffer_out == nullptr) {
1396         return UNEXPECTED_NULL;
1397     }
1398     return status;
1399 }
1400 
readNullableEmbeddedBuffer(size_t buffer_size,size_t * buffer_handle,size_t parent_buffer_handle,size_t parent_offset,const void ** buffer_out) const1401 status_t Parcel::readNullableEmbeddedBuffer(size_t buffer_size,
1402                                             size_t *buffer_handle,
1403                                             size_t parent_buffer_handle,
1404                                             size_t parent_offset,
1405                                             const void **buffer_out) const
1406 {
1407     return readBuffer(buffer_size, buffer_handle, BINDER_BUFFER_FLAG_HAS_PARENT,
1408                       parent_buffer_handle, parent_offset, buffer_out);
1409 }
1410 
readEmbeddedNativeHandle(size_t parent_buffer_handle,size_t parent_offset,const native_handle_t ** handle) const1411 status_t Parcel::readEmbeddedNativeHandle(size_t parent_buffer_handle,
1412                                           size_t parent_offset,
1413                                           const native_handle_t **handle) const
1414 {
1415     status_t status = readNullableEmbeddedNativeHandle(parent_buffer_handle, parent_offset, handle);
1416     if (status == OK && *handle == nullptr) {
1417         return UNEXPECTED_NULL;
1418     }
1419     return status;
1420 }
1421 
readNullableNativeHandleNoDup(const native_handle_t ** handle,bool embedded,size_t parent_buffer_handle,size_t parent_offset) const1422 status_t Parcel::readNullableNativeHandleNoDup(const native_handle_t **handle,
1423                                                bool embedded,
1424                                                size_t parent_buffer_handle,
1425                                                size_t parent_offset) const
1426 {
1427     uint64_t nativeHandleSize;
1428     status_t status = readUint64(&nativeHandleSize);
1429     if (status != OK) {
1430         return BAD_VALUE;
1431     }
1432 
1433     if (nativeHandleSize == 0) {
1434         // If !embedded, then parent_* vars are 0 and don't actually correspond
1435         // to anything. In that case, we're actually reading this data into
1436         // writable memory, and the handle returned from here will actually be
1437         // used (rather than be ignored).
1438         if (embedded) {
1439             if(!validateBufferParent(parent_buffer_handle, parent_offset)) {
1440                 ALOGE("Buffer in parent %zu offset %zu invalid.", parent_buffer_handle, parent_offset);
1441                 return BAD_VALUE;
1442             }
1443 
1444             binder_buffer_object *parentBuffer =
1445                 reinterpret_cast<binder_buffer_object*>(mData + mObjects[parent_buffer_handle]);
1446 
1447             void* bufferInParent = *reinterpret_cast<void**>(
1448                 reinterpret_cast<uint8_t*>(parentBuffer->buffer) + parent_offset);
1449 
1450             if (bufferInParent != nullptr) {
1451                   ALOGE("Buffer in (handle) parent %p is not nullptr.", bufferInParent);
1452                   android_errorWriteLog(0x534e4554, "179289794");
1453                   return BAD_VALUE;
1454             }
1455         }
1456 
1457         *handle = nullptr;
1458         return status;
1459     }
1460 
1461     if (nativeHandleSize < sizeof(native_handle_t) || nativeHandleSize > std::numeric_limits<uint32_t>::max()) {
1462         ALOGE("Invalid native_handle_t size: %" PRIu64, nativeHandleSize);
1463         return BAD_VALUE;
1464     }
1465 
1466     size_t fdaParent;
1467     if (embedded) {
1468         status = readNullableEmbeddedBuffer(nativeHandleSize, &fdaParent,
1469                                             parent_buffer_handle, parent_offset,
1470                                             reinterpret_cast<const void**>(handle));
1471     } else {
1472         status = readNullableBuffer(nativeHandleSize, &fdaParent,
1473                                     reinterpret_cast<const void**>(handle));
1474     }
1475 
1476     if (status != OK) {
1477         return status;
1478     }
1479 
1480     if (*handle == nullptr) {
1481         // null handle already read above
1482         ALOGE("Expecting non-null handle buffer");
1483         return BAD_VALUE;
1484     }
1485 
1486     int numFds = (*handle)->numFds;
1487     int numInts = (*handle)->numInts;
1488 
1489     if (numFds < 0 || numFds > NATIVE_HANDLE_MAX_FDS) {
1490         ALOGE("Received native_handle with invalid number of fds.");
1491         return BAD_VALUE;
1492     }
1493 
1494     if (numInts < 0 || numInts > NATIVE_HANDLE_MAX_INTS) {
1495         ALOGE("Received native_handle with invalid number of ints.");
1496         return BAD_VALUE;
1497     }
1498 
1499     if (nativeHandleSize != (sizeof(native_handle_t) + ((numFds + numInts) * sizeof(int)))) {
1500         ALOGE("Size of native_handle doesn't match.");
1501         return BAD_VALUE;
1502     }
1503 
1504     const binder_fd_array_object* fd_array_obj = readObject<binder_fd_array_object>();
1505 
1506     if (fd_array_obj == nullptr || fd_array_obj->hdr.type != BINDER_TYPE_FDA) {
1507         ALOGE("Can't find file-descriptor array object.");
1508         return BAD_VALUE;
1509     }
1510 
1511     if (static_cast<int>(fd_array_obj->num_fds) != numFds) {
1512         ALOGE("Number of native handles does not match.");
1513         return BAD_VALUE;
1514     }
1515 
1516     if (fd_array_obj->parent != fdaParent) {
1517         ALOGE("Parent handle of file-descriptor array not correct.");
1518         return BAD_VALUE;
1519     }
1520 
1521     if (fd_array_obj->parent_offset != offsetof(native_handle_t, data)) {
1522         ALOGE("FD array object not properly offset in parent.");
1523         return BAD_VALUE;
1524     }
1525 
1526     return OK;
1527 }
1528 
readNullableEmbeddedNativeHandle(size_t parent_buffer_handle,size_t parent_offset,const native_handle_t ** handle) const1529 status_t Parcel::readNullableEmbeddedNativeHandle(size_t parent_buffer_handle,
1530                                                   size_t parent_offset,
1531                                                   const native_handle_t **handle) const
1532 {
1533     return readNullableNativeHandleNoDup(handle, true /* embedded */, parent_buffer_handle,
1534                                          parent_offset);
1535 }
1536 
readNativeHandleNoDup(const native_handle_t ** handle) const1537 status_t Parcel::readNativeHandleNoDup(const native_handle_t **handle) const
1538 {
1539     status_t status = readNullableNativeHandleNoDup(handle);
1540     if (status == OK && *handle == nullptr) {
1541         return UNEXPECTED_NULL;
1542     }
1543     return status;
1544 }
1545 
readNullableNativeHandleNoDup(const native_handle_t ** handle) const1546 status_t Parcel::readNullableNativeHandleNoDup(const native_handle_t **handle) const
1547 {
1548     return readNullableNativeHandleNoDup(handle, false /* embedded */);
1549 }
1550 
closeFileDescriptors()1551 void Parcel::closeFileDescriptors()
1552 {
1553     size_t i = mObjectsSize;
1554     if (i > 0) {
1555         //ALOGI("Closing file descriptors for %zu objects...", i);
1556     }
1557     while (i > 0) {
1558         i--;
1559         const flat_binder_object* flat
1560             = reinterpret_cast<flat_binder_object*>(mData+mObjects[i]);
1561         if (flat->hdr.type == BINDER_TYPE_FD) {
1562             //ALOGI("Closing fd: %ld", flat->handle);
1563             close(flat->handle);
1564         }
1565     }
1566 }
1567 
ipcData() const1568 uintptr_t Parcel::ipcData() const
1569 {
1570     return reinterpret_cast<uintptr_t>(mData);
1571 }
1572 
ipcDataSize() const1573 size_t Parcel::ipcDataSize() const
1574 {
1575     return mDataSize > mDataPos ? mDataSize : mDataPos;
1576 }
1577 
ipcObjects() const1578 uintptr_t Parcel::ipcObjects() const
1579 {
1580     return reinterpret_cast<uintptr_t>(mObjects);
1581 }
1582 
ipcObjectsCount() const1583 size_t Parcel::ipcObjectsCount() const
1584 {
1585     return mObjectsSize;
1586 }
1587 
1588 #define BUFFER_ALIGNMENT_BYTES 8
ipcBufferSize() const1589 size_t Parcel::ipcBufferSize() const
1590 {
1591     size_t totalBuffersSize = 0;
1592     // Add size for BINDER_TYPE_PTR
1593     size_t i = mObjectsSize;
1594     while (i > 0) {
1595         i--;
1596         const binder_buffer_object* buffer
1597             = reinterpret_cast<binder_buffer_object*>(mData+mObjects[i]);
1598         if (buffer->hdr.type == BINDER_TYPE_PTR) {
1599             /* The binder kernel driver requires each buffer to be 8-byte
1600              * aligned */
1601             size_t alignedSize = (buffer->length + (BUFFER_ALIGNMENT_BYTES - 1))
1602                     & ~(BUFFER_ALIGNMENT_BYTES - 1);
1603             if (alignedSize > SIZE_MAX - totalBuffersSize) {
1604                 ALOGE("ipcBuffersSize(): invalid buffer sizes.");
1605                 return 0;
1606             }
1607             totalBuffersSize += alignedSize;
1608         }
1609     }
1610     return totalBuffersSize;
1611 }
1612 
ipcSetDataReference(const uint8_t * data,size_t dataSize,const binder_size_t * objects,size_t objectsCount,release_func relFunc,void * relCookie)1613 void Parcel::ipcSetDataReference(const uint8_t* data, size_t dataSize,
1614     const binder_size_t* objects, size_t objectsCount, release_func relFunc, void* relCookie)
1615 {
1616     binder_size_t minOffset = 0;
1617     freeDataNoInit();
1618     mError = NO_ERROR;
1619     mData = const_cast<uint8_t*>(data);
1620     mDataSize = mDataCapacity = dataSize;
1621     //ALOGI("setDataReference Setting data size of %p to %lu (pid=%d)", this, mDataSize, getpid());
1622     mDataPos = 0;
1623     ALOGV("setDataReference Setting data pos of %p to %zu", this, mDataPos);
1624     mObjects = const_cast<binder_size_t*>(objects);
1625     mObjectsSize = mObjectsCapacity = objectsCount;
1626     mNextObjectHint = 0;
1627     clearCache();
1628     mOwner = relFunc;
1629     mOwnerCookie = relCookie;
1630     for (size_t i = 0; i < mObjectsSize; i++) {
1631         binder_size_t offset = mObjects[i];
1632         if (offset < minOffset) {
1633             ALOGE("%s: bad object offset %" PRIu64 " < %" PRIu64 "\n",
1634                   __func__, (uint64_t)offset, (uint64_t)minOffset);
1635             mObjectsSize = 0;
1636             break;
1637         }
1638         minOffset = offset + sizeof(flat_binder_object);
1639     }
1640     scanForFds();
1641 }
1642 
print(TextOutput & to,uint32_t) const1643 void Parcel::print(TextOutput& to, uint32_t /*flags*/) const
1644 {
1645     to << "Parcel(";
1646 
1647     if (errorCheck() != NO_ERROR) {
1648         const status_t err = errorCheck();
1649         to << "Error: " << (void*)(intptr_t)err << " \"" << strerror(-err) << "\"";
1650     } else if (dataSize() > 0) {
1651         const uint8_t* DATA = data();
1652         to << indent << HexDump(DATA, dataSize()) << dedent;
1653         const binder_size_t* OBJS = objects();
1654         const size_t N = objectsCount();
1655         for (size_t i=0; i<N; i++) {
1656             const flat_binder_object* flat
1657                 = reinterpret_cast<const flat_binder_object*>(DATA+OBJS[i]);
1658             if (flat->hdr.type == BINDER_TYPE_PTR) {
1659                 const binder_buffer_object* buffer
1660                     = reinterpret_cast<const binder_buffer_object*>(DATA+OBJS[i]);
1661                 HexDump bufferDump((const uint8_t*)buffer->buffer, (size_t)buffer->length);
1662                 bufferDump.setSingleLineCutoff(0);
1663                 to << endl << "Object #" << i << " @ " << (void*)OBJS[i] << " (buffer size " << buffer->length << "):";
1664                 to << indent << bufferDump << dedent;
1665             } else {
1666                 to << endl << "Object #" << i << " @ " << (void*)OBJS[i] << ": "
1667                     << TypeCode(flat->hdr.type & 0x7f7f7f00)
1668                     << " = " << flat->binder;
1669             }
1670         }
1671     } else {
1672         to << "NULL";
1673     }
1674 
1675     to << ")";
1676 }
1677 
releaseObjects()1678 void Parcel::releaseObjects()
1679 {
1680     const sp<ProcessState> proc(ProcessState::self());
1681     size_t i = mObjectsSize;
1682     uint8_t* const data = mData;
1683     binder_size_t* const objects = mObjects;
1684     while (i > 0) {
1685         i--;
1686         const flat_binder_object* flat
1687             = reinterpret_cast<flat_binder_object*>(data+objects[i]);
1688         release_object(proc, *flat, this);
1689     }
1690 }
1691 
acquireObjects()1692 void Parcel::acquireObjects()
1693 {
1694     const sp<ProcessState> proc(ProcessState::self());
1695     size_t i = mObjectsSize;
1696     uint8_t* const data = mData;
1697     binder_size_t* const objects = mObjects;
1698     while (i > 0) {
1699         i--;
1700         const binder_object_header* flat
1701             = reinterpret_cast<binder_object_header*>(data+objects[i]);
1702         acquire_object(proc, *flat, this);
1703     }
1704 }
1705 
freeData()1706 void Parcel::freeData()
1707 {
1708     freeDataNoInit();
1709     initState();
1710 }
1711 
freeDataNoInit()1712 void Parcel::freeDataNoInit()
1713 {
1714     if (mOwner) {
1715         LOG_ALLOC("Parcel %p: freeing other owner data", this);
1716         //ALOGI("Freeing data ref of %p (pid=%d)", this, getpid());
1717         mOwner(this, mData, mDataSize, mObjects, mObjectsSize, mOwnerCookie);
1718     } else {
1719         LOG_ALLOC("Parcel %p: freeing allocated data", this);
1720         releaseObjects();
1721         if (mData) {
1722             LOG_ALLOC("Parcel %p: freeing with %zu capacity", this, mDataCapacity);
1723             gParcelGlobalAllocSize -= mDataCapacity;
1724             gParcelGlobalAllocCount--;
1725             if (mDeallocZero) {
1726                 zeroMemory(mData, mDataSize);
1727             }
1728             free(mData);
1729         }
1730         if (mObjects) free(mObjects);
1731     }
1732 }
1733 
growData(size_t len)1734 status_t Parcel::growData(size_t len)
1735 {
1736     if (len > INT32_MAX) {
1737         // don't accept size_t values which may have come from an
1738         // inadvertent conversion from a negative int.
1739         return BAD_VALUE;
1740     }
1741     if (len > SIZE_MAX - mDataSize) return NO_MEMORY; // overflow
1742     if (mDataSize + len > SIZE_MAX / 3) return NO_MEMORY; // overflow
1743     size_t newSize = ((mDataSize+len)*3)/2;
1744     return continueWrite(newSize);
1745 }
1746 
reallocZeroFree(uint8_t * data,size_t oldCapacity,size_t newCapacity,bool zero)1747 static uint8_t* reallocZeroFree(uint8_t* data, size_t oldCapacity, size_t newCapacity, bool zero) {
1748     if (!zero) {
1749         return (uint8_t*)realloc(data, newCapacity);
1750     }
1751     uint8_t* newData = (uint8_t*)malloc(newCapacity);
1752     if (!newData) {
1753         return nullptr;
1754     }
1755 
1756     memcpy(newData, data, std::min(oldCapacity, newCapacity));
1757     zeroMemory(data, oldCapacity);
1758     free(data);
1759     return newData;
1760 }
1761 
continueWrite(size_t desired)1762 status_t Parcel::continueWrite(size_t desired)
1763 {
1764     if (desired > INT32_MAX) {
1765         // don't accept size_t values which may have come from an
1766         // inadvertent conversion from a negative int.
1767         return BAD_VALUE;
1768     }
1769 
1770     // If shrinking, first adjust for any objects that appear
1771     // after the new data size.
1772     size_t objectsSize = mObjectsSize;
1773     if (desired < mDataSize) {
1774         if (desired == 0) {
1775             objectsSize = 0;
1776         } else {
1777             while (objectsSize > 0) {
1778                 if (mObjects[objectsSize-1] < desired)
1779                     break;
1780                 objectsSize--;
1781             }
1782         }
1783     }
1784 
1785     if (mOwner) {
1786         // If the size is going to zero, just release the owner's data.
1787         if (desired == 0) {
1788             freeData();
1789             return NO_ERROR;
1790         }
1791 
1792         // If there is a different owner, we need to take
1793         // posession.
1794         uint8_t* data = (uint8_t*)malloc(desired);
1795         if (!data) {
1796             mError = NO_MEMORY;
1797             return NO_MEMORY;
1798         }
1799         binder_size_t* objects = nullptr;
1800 
1801         if (objectsSize) {
1802             objects = (binder_size_t*)calloc(objectsSize, sizeof(binder_size_t));
1803             if (!objects) {
1804                 free(data);
1805 
1806                 mError = NO_MEMORY;
1807                 return NO_MEMORY;
1808             }
1809 
1810             // Little hack to only acquire references on objects
1811             // we will be keeping.
1812             size_t oldObjectsSize = mObjectsSize;
1813             mObjectsSize = objectsSize;
1814             acquireObjects();
1815             mObjectsSize = oldObjectsSize;
1816         }
1817 
1818         if (mData) {
1819             memcpy(data, mData, mDataSize < desired ? mDataSize : desired);
1820         }
1821         if (objects && mObjects) {
1822             memcpy(objects, mObjects, objectsSize*sizeof(binder_size_t));
1823         }
1824         //ALOGI("Freeing data ref of %p (pid=%d)", this, getpid());
1825         mOwner(this, mData, mDataSize, mObjects, mObjectsSize, mOwnerCookie);
1826         mOwner = nullptr;
1827 
1828         LOG_ALLOC("Parcel %p: taking ownership of %zu capacity", this, desired);
1829         gParcelGlobalAllocSize += desired;
1830         gParcelGlobalAllocCount++;
1831 
1832         mData = data;
1833         mObjects = objects;
1834         mDataSize = (mDataSize < desired) ? mDataSize : desired;
1835         ALOGV("continueWrite Setting data size of %p to %zu", this, mDataSize);
1836         mDataCapacity = desired;
1837         mObjectsSize = mObjectsCapacity = objectsSize;
1838         mNextObjectHint = 0;
1839 
1840         clearCache();
1841     } else if (mData) {
1842         if (objectsSize < mObjectsSize) {
1843             // Need to release refs on any objects we are dropping.
1844             const sp<ProcessState> proc(ProcessState::self());
1845             for (size_t i=objectsSize; i<mObjectsSize; i++) {
1846                 const flat_binder_object* flat
1847                     = reinterpret_cast<flat_binder_object*>(mData+mObjects[i]);
1848                 if (flat->hdr.type == BINDER_TYPE_FD) {
1849                     // will need to rescan because we may have lopped off the only FDs
1850                     mFdsKnown = false;
1851                 }
1852                 release_object(proc, *flat, this);
1853             }
1854 
1855             if (objectsSize == 0) {
1856                 free(mObjects);
1857                 mObjects = nullptr;
1858             } else {
1859                 binder_size_t* objects =
1860                     (binder_size_t*)realloc(mObjects, objectsSize*sizeof(binder_size_t));
1861                 if (objects) {
1862                     mObjects = objects;
1863                 }
1864             }
1865             mObjectsSize = objectsSize;
1866             mNextObjectHint = 0;
1867 
1868             clearCache();
1869         }
1870 
1871         // We own the data, so we can just do a realloc().
1872         if (desired > mDataCapacity) {
1873             uint8_t* data = reallocZeroFree(mData, mDataCapacity, desired, mDeallocZero);
1874             if (data) {
1875                 LOG_ALLOC("Parcel %p: continue from %zu to %zu capacity", this, mDataCapacity,
1876                         desired);
1877                 gParcelGlobalAllocSize += desired;
1878                 gParcelGlobalAllocSize -= mDataCapacity;
1879                 mData = data;
1880                 mDataCapacity = desired;
1881             } else {
1882                 mError = NO_MEMORY;
1883                 return NO_MEMORY;
1884             }
1885         } else {
1886             if (mDataSize > desired) {
1887                 mDataSize = desired;
1888                 ALOGV("continueWrite Setting data size of %p to %zu", this, mDataSize);
1889             }
1890             if (mDataPos > desired) {
1891                 mDataPos = desired;
1892                 ALOGV("continueWrite Setting data pos of %p to %zu", this, mDataPos);
1893             }
1894         }
1895 
1896     } else {
1897         // This is the first data.  Easy!
1898         uint8_t* data = (uint8_t*)malloc(desired);
1899         if (!data) {
1900             mError = NO_MEMORY;
1901             return NO_MEMORY;
1902         }
1903 
1904         if(!(mDataCapacity == 0 && mObjects == nullptr
1905              && mObjectsCapacity == 0)) {
1906             ALOGE("continueWrite: %zu/%p/%zu/%zu", mDataCapacity, mObjects, mObjectsCapacity, desired);
1907         }
1908 
1909         LOG_ALLOC("Parcel %p: allocating with %zu capacity", this, desired);
1910         gParcelGlobalAllocSize += desired;
1911         gParcelGlobalAllocCount++;
1912 
1913         mData = data;
1914         mDataSize = mDataPos = 0;
1915         ALOGV("continueWrite Setting data size of %p to %zu", this, mDataSize);
1916         ALOGV("continueWrite Setting data pos of %p to %zu", this, mDataPos);
1917         mDataCapacity = desired;
1918     }
1919 
1920     return NO_ERROR;
1921 }
1922 
initState()1923 void Parcel::initState()
1924 {
1925     LOG_ALLOC("Parcel %p: initState", this);
1926     mError = NO_ERROR;
1927     mData = nullptr;
1928     mDataSize = 0;
1929     mDataCapacity = 0;
1930     mDataPos = 0;
1931     ALOGV("initState Setting data size of %p to %zu", this, mDataSize);
1932     ALOGV("initState Setting data pos of %p to %zu", this, mDataPos);
1933     mObjects = nullptr;
1934     mObjectsSize = 0;
1935     mObjectsCapacity = 0;
1936     mNextObjectHint = 0;
1937     mHasFds = false;
1938     mFdsKnown = true;
1939     mAllowFds = true;
1940     mDeallocZero = false;
1941     mOwner = nullptr;
1942     clearCache();
1943 
1944     // racing multiple init leads only to multiple identical write
1945     if (gMaxFds == 0) {
1946         struct rlimit result;
1947         if (!getrlimit(RLIMIT_NOFILE, &result)) {
1948             gMaxFds = (size_t)result.rlim_cur;
1949             //ALOGI("parcel fd limit set to %zu", gMaxFds);
1950         } else {
1951             ALOGW("Unable to getrlimit: %s", strerror(errno));
1952             gMaxFds = 1024;
1953         }
1954     }
1955 }
1956 
scanForFds() const1957 void Parcel::scanForFds() const
1958 {
1959     bool hasFds = false;
1960     for (size_t i=0; i<mObjectsSize; i++) {
1961         const flat_binder_object* flat
1962             = reinterpret_cast<const flat_binder_object*>(mData + mObjects[i]);
1963         if (flat->hdr.type == BINDER_TYPE_FD) {
1964             hasFds = true;
1965             break;
1966         }
1967     }
1968     mHasFds = hasFds;
1969     mFdsKnown = true;
1970 }
1971 
1972 } // namespace hardware
1973 } // namespace android
1974