diff --git a/include/core/SkData.h b/include/core/SkData.h
index eb845b5ad3..2a4b40d5f6 100644
--- a/include/core/SkData.h
+++ b/include/core/SkData.h
@@ -86,6 +86,12 @@ public:
      */
     static sk_sp<SkData> MakeUninitialized(size_t length);
 
+    /**
+     *  Create a new data with zero-initialized contents. The caller should call writable_data()
+     *  to write into the buffer, but this must be done before another ref() is made.
+     */
+    static sk_sp<SkData> MakeZeroInitialized(size_t length);
+
     /**
      *  Create a new dataref by copying the specified c-string
      *  (a null-terminated array of bytes). The returned SkData will have size()
diff --git a/include/effects/SkRuntimeEffect.h b/include/effects/SkRuntimeEffect.h
index 15cf6e5e37..7226d0f0ff 100644
--- a/include/effects/SkRuntimeEffect.h
+++ b/include/effects/SkRuntimeEffect.h
@@ -380,7 +380,7 @@ protected:
     SkRuntimeEffectBuilder() = delete;
     explicit SkRuntimeEffectBuilder(sk_sp<SkRuntimeEffect> effect)
             : fEffect(std::move(effect))
-            , fUniforms(SkData::MakeUninitialized(fEffect->uniformSize()))
+            , fUniforms(SkData::MakeZeroInitialized(fEffect->uniformSize()))
             , fChildren(fEffect->children().size()) {}
 
     SkRuntimeEffectBuilder(SkRuntimeEffectBuilder&&) = default;
diff --git a/src/core/SkData.cpp b/src/core/SkData.cpp
index f9575426a9..e33846b000 100644
--- a/src/core/SkData.cpp
+++ b/src/core/SkData.cpp
@@ -111,6 +111,14 @@ sk_sp<SkData> SkData::MakeUninitialized(size_t length) {
     return PrivateNewWithCopy(nullptr, length);
 }
 
+sk_sp<SkData> SkData::MakeZeroInitialized(size_t length) {
+    auto data = MakeUninitialized(length);
+    if (length != 0) {
+        memset(data->writable_data(), 0, data->size());
+    }
+    return data;
+}
+
 sk_sp<SkData> SkData::MakeWithProc(const void* ptr, size_t length, ReleaseProc proc, void* ctx) {
     return sk_sp<SkData>(new SkData(ptr, length, proc, ctx));
 }