Fixed a few places where uninitialized memory could have been read

src/core/SkImageFilter.cpp

Index: src/core/SkImageFilter.cpp
diff --git a/src/core/SkImageFilter.cpp b/src/core/SkImageFilter.cpp
index aadf9040b0403ae1ef8d256e73f6f1aad8d2c5e5..d6b4fcc632e34eb3f50ce00b871ffe74fe51a8ce 100644
--- a/src/core/SkImageFilter.cpp
+++ b/src/core/SkImageFilter.cpp
@@ -63,10 +63,14 @@ SkImageFilter::SkImageFilter(int inputCount, SkFlattenableReadBuffer& buffer) {
             } else {
                 fInputs[i] = NULL;
             }
+            if (!buffer.validate(true)) {
+                fInputCount = i; // Do not use fInputs past that point in the destructor
+                break;
+            }
         }
         SkRect rect;
         buffer.readRect(&rect);
-        if (buffer.validate(SkIsValidRect(rect))) {
+        if (buffer.validate(true) && buffer.validate(SkIsValidRect(rect))) {

[sugoi1, 2013/12/05 18:45:47]

This extra validate(true) makes sure that we don't read uninitialized memory in
SkIsValidRect.

[Stephen White, 2013/12/05 20:48:22]

This is ok, but I'd still prefer we had some kind of buffer.isValid() to make
the intent clearer. Could wait for a followup, I suppose. Either way, a comment
might help too.

             uint32_t flags = buffer.readUInt();
             fCropRect = CropRect(rect, flags);
         }