enforce 4-byte alignment and length for buffers

Bug:792859
Change-Id: Ib4cde1015429153709956d4ffc2d4321decb79b0
Reviewed-on: https://skia-review.googlesource.com/82160
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Reed <reed@google.com>

2 files changed, 8 insertions, 20 deletions

diff --git a/src/core/SkReadBuffer.cpp b/src/core/SkReadBuffer.cpp
index 78071ee227..e3651cc3a2 100644
--- a/src/core/SkReadBuffer.cpp
+++ b/src/core/SkReadBuffer.cpp
@@ -63,7 +63,7 @@ SkReadBuffer::SkReadBuffer() {
 SkReadBuffer::SkReadBuffer(const void* data, size_t size) {
     fFlags = default_flags();
     fVersion = 0;
-    fReader.setMemory(data, size);
+    this->setMemory(data, size);
     fMemoryPtr = nullptr;
 
     fTFArray = nullptr;
@@ -76,28 +76,16 @@ SkReadBuffer::SkReadBuffer(const void* data, size_t size) {
 #endif // DEBUG_NON_DETERMINISTIC_ASSERT
 }
 
-SkReadBuffer::SkReadBuffer(SkStream* stream) {
-    fFlags = default_flags();
-    fVersion = 0;
-    const size_t length = stream->getLength();
-    fMemoryPtr = sk_malloc_throw(length);
-    stream->read(fMemoryPtr, length);
-    fReader.setMemory(fMemoryPtr, length);
-
-    fTFArray = nullptr;
-    fTFCount = 0;
-
-    fFactoryArray = nullptr;
-    fFactoryCount = 0;
-#ifdef DEBUG_NON_DETERMINISTIC_ASSERT
-    fDecodedBitmapIndex = -1;
-#endif // DEBUG_NON_DETERMINISTIC_ASSERT
-}
-
 SkReadBuffer::~SkReadBuffer() {
     sk_free(fMemoryPtr);
 }
 
+void SkReadBuffer::setMemory(const void* data, size_t size) {
+    this->validate(IsPtrAlign4(data) && (SkAlign4(size) == size));
+    if (!fError) {
+        fReader.setMemory(data, size);
+    }
+}
 void SkReadBuffer::setInvalid() {
     if (!fError) {
         // When an error is found, send the read cursor to the end of the stream
diff --git a/src/core/SkReadBuffer.h b/src/core/SkReadBuffer.h
index 78038aa7af..6819c47904 100644
--- a/src/core/SkReadBuffer.h
+++ b/src/core/SkReadBuffer.h
@@ -36,7 +36,6 @@ class SkReadBuffer {
 public:
     SkReadBuffer();
     SkReadBuffer(const void* data, size_t size);
-    SkReadBuffer(SkStream* stream);
     virtual ~SkReadBuffer();
 
     virtual SkReadBuffer* clone(const void* data, size_t size) const {
@@ -276,6 +275,7 @@ protected:
 private:
     void setInvalid();
     bool readArray(void* value, size_t size, size_t elementSize);
+    void setMemory(const void*, size_t);
 
     uint32_t fFlags;
     int fVersion;