Checking structure sizes before reading them from memory to avoid overflowing the buffer's stream.

src/core/SkPath.cpp

Index: src/core/SkPath.cpp
diff --git a/src/core/SkPath.cpp b/src/core/SkPath.cpp
index 60cfe0373c08628573cf5be16ff829f428e7cd0f..c480624a166a287a56701259adf8609c4bdf2dee 100644
--- a/src/core/SkPath.cpp
+++ b/src/core/SkPath.cpp
@@ -2066,7 +2066,7 @@ SkPath::Verb SkPath::RawIter::next(SkPoint pts[4]) {
     Format in compressed buffer: [ptCount, verbCount, pts[], verbs[]]
 */
 
-uint32_t SkPath::writeToMemory(void* storage) const {
+size_t SkPath::writeToMemory(void* storage) const {
     SkDEBUGCODE(this->validate();)
 
     if (NULL == storage) {
@@ -2090,11 +2090,11 @@ uint32_t SkPath::writeToMemory(void* storage) const {
     fPathRef->writeToBuffer(&buffer);
 
     buffer.padToAlign4();
-    return SkToU32(buffer.pos());
+    return buffer.pos();
 }
 
-uint32_t SkPath::readFromMemory(const void* storage) {
-    SkRBuffer   buffer(storage);
+size_t SkPath::readFromMemory(const void* storage, size_t length) {
+    SkRBufferWithSizeCheck buffer(storage, length);
 
     uint32_t packed = buffer.readS32();
     fIsOval = (packed >> kIsOval_SerializationShift) & 1;
@@ -2108,14 +2108,18 @@ uint32_t SkPath::readFromMemory(const void* storage) {
 
     fPathRef.reset(SkPathRef::CreateFromBuffer(&buffer
 #ifndef DELETE_THIS_CODE_WHEN_SKPS_ARE_REBUILT_AT_V14_AND_ALL_OTHER_INSTANCES_TOO
-        , newFormat, packed)
+        , newFormat, packed
 #endif
-        );
+        ));
 
     buffer.skipToAlign4();
 
-    SkDEBUGCODE(this->validate();)
-    return SkToU32(buffer.pos());
+    size_t sizeRead = 0;
+    if (buffer.isValid()) {
+        SkDEBUGCODE(this->validate();)
+        sizeRead = buffer.pos();
+    }
+    return sizeRead;
 }
 
 ///////////////////////////////////////////////////////////////////////////////