Fixed more fuzzer issues

- Added the "isAvailable" function to check how much bytes are remaining in the stream before doing potentially large mallocs. That way, we can signal a bad stream instead of crashing.
- Added data validation in SkImageInfo.cpp
- Added NULL pointer check in displacement
- Modified the fuzzer for randomized bitmap types

BUG=328934,329254
R=senorblanco@google.com, senorblanco@chromium.org, reed@google.com, sugoi@google.com

Author: sugoi@chromium.org

Review URL: https://codereview.chromium.org/116773002

git-svn-id: http://skia.googlecode.com/svn/trunk@12723 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 2 insertions, 1 deletions

diff --git a/src/effects/SkMergeImageFilter.cpp b/src/effects/SkMergeImageFilter.cpp
index 33673b0639..528fe823eb 100755
--- a/src/effects/SkMergeImageFilter.cpp
+++ b/src/effects/SkMergeImageFilter.cpp
@@ -165,7 +165,8 @@ SkMergeImageFilter::SkMergeImageFilter(SkFlattenableReadBuffer& buffer)
         int nbInputs = countInputs();
         size_t size = nbInputs * sizeof(fModes[0]);
         SkASSERT(buffer.getArrayCount() == size);
-        if (buffer.readByteArray(fModes, size)) {
+        if (buffer.validate(buffer.getArrayCount() == size) &&
+            buffer.readByteArray(fModes, size)) {
             for (int i = 0; i < nbInputs; ++i) {
                 buffer.validate(SkIsValidMode((SkXfermode::Mode)fModes[i]));
             }