1 files changed, 60 insertions, 11 deletions

diff --git a/dom/base/nsContentUtils.cpp b/dom/base/nsContentUtils.cpp
index 34c7d23b8..3696195dd 100644
--- a/dom/base/nsContentUtils.cpp
+++ b/dom/base/nsContentUtils.cpp
@@ -7597,6 +7597,24 @@ nsContentUtils::IsFileImage(nsIFile* aFile, nsACString& aType)
 }
 
 nsresult
+nsContentUtils::CalculateBufferSizeForImage(const uint32_t& aStride,
+                                            const IntSize& aImageSize,
+                                            const SurfaceFormat& aFormat,
+                                            size_t* aMaxBufferSize,
+                                            size_t* aUsedBufferSize)
+{
+  CheckedInt32 requiredBytes =
+    CheckedInt32(aStride) * CheckedInt32(aImageSize.height);
+  if (!requiredBytes.isValid()) {
+    return NS_ERROR_FAILURE;
+  }
+  *aMaxBufferSize = requiredBytes.value();
+  *aUsedBufferSize = *aMaxBufferSize - aStride + 
+                     (aImageSize.width * BytesPerPixel(aFormat));
+  return NS_OK;
+}
+
+nsresult
 nsContentUtils::DataTransferItemToImage(const IPCDataTransferItem& aItem,
                                         imgIContainer** aContainer)
 {
@@ -7611,6 +7629,22 @@ nsContentUtils::DataTransferItemToImage(const IPCDataTransferItem& aItem,
 
   Shmem data = aItem.data().get_Shmem();
 
+  // Validate shared memory buffer size
+  size_t imageBufLen = 0;
+  size_t maxBufLen = 0;
+  nsresult rv = CalculateBufferSizeForImage(imageDetails.stride(),
+                                            size,
+                                            static_cast<SurfaceFormat>(
+                                              imageDetails.format()),
+                                            &maxBufLen,
+                                            &imageBufLen);
+  if (NS_FAILED(rv)) {
+    return rv;
+  }
+  if (imageBufLen > data.Size<uint8_t>()) {
+    return NS_ERROR_FAILURE;
+  }
+
   RefPtr<DataSourceSurface> image =
       CreateDataSourceSurfaceFromData(size,
                                       static_cast<SurfaceFormat>(imageDetails.format()),
@@ -7950,20 +7984,19 @@ GetSurfaceDataImpl(mozilla::gfx::DataSourceSurface* aSurface,
     return GetSurfaceDataContext::NullValue();
   }
 
-  mozilla::gfx::IntSize size = aSurface->GetSize();
-  mozilla::CheckedInt32 requiredBytes =
-    mozilla::CheckedInt32(map.mStride) * mozilla::CheckedInt32(size.height);
-  if (!requiredBytes.isValid()) {
+  size_t bufLen = 0;
+  size_t maxBufLen = 0;
+  nsresult rv = nsContentUtils::CalculateBufferSizeForImage(map.mStride,
+                                                            aSurface->GetSize(),
+                                                            aSurface->GetFormat(),
+                                                            &maxBufLen,
+                                                            &bufLen);
+  if (NS_FAILED(rv)) {
+    // Release mapped memory
+    aSurface->Unmap();
     return GetSurfaceDataContext::NullValue();
   }
 
-  size_t maxBufLen = requiredBytes.value();
-  mozilla::gfx::SurfaceFormat format = aSurface->GetFormat();
-
-  // Surface data handling is totally nuts. This is the magic one needs to
-  // know to access the data.
-  size_t bufLen = maxBufLen - map.mStride + (size.width * BytesPerPixel(format));
-
   // nsDependentCString wants null-terminated string.
   typename GetSurfaceDataContext::ReturnType surfaceData = aContext.Allocate(maxBufLen + 1);
   if (GetSurfaceDataContext::GetBuffer(surfaceData)) {
@@ -9787,3 +9820,19 @@ nsContentUtils::AttemptLargeAllocationLoad(nsIHttpChannel* aChannel)
 
   return reloadSucceeded;
 }
+
+/* static */ bool
+nsContentUtils::IsLocalRefURL(const nsString& aString)
+{
+  // Find the first non-"C0 controls + space" character.
+  const char16_t* current = aString.get();
+  for (; *current != '\0'; current++) {
+    if (*current > 0x20) {
+      // if the first non-"C0 controls + space" character is '#', this is a
+      // local-ref URL.
+      return *current == '#';
+    }
+  }
+
+  return false;
+}
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