Fix crash in TextDropShadowCache

The lengths used to copy/read arrays were completely wrong.

Change-Id: If21f23a73cce59bbd32975760e6d728eeeb9e40d

1 files changed, 8 insertions, 4 deletions

diff --git a/libs/hwui/TextDropShadowCache.cpp b/libs/hwui/TextDropShadowCache.cpp
index 4d80f7382318..9c7a5ab3d077 100644
--- a/libs/hwui/TextDropShadowCache.cpp
+++ b/libs/hwui/TextDropShadowCache.cpp
@@ -30,7 +30,7 @@ namespace uirenderer {
 ///////////////////////////////////////////////////////////////////////////////
 
 hash_t ShadowText::hash() const {
-    uint32_t charCount = len * sizeof(char16_t);
+    uint32_t charCount = len / sizeof(char16_t);
     uint32_t hash = JenkinsHashMix(0, len);
     hash = JenkinsHashMix(hash, android::hash_type(radius));
     hash = JenkinsHashMix(hash, android::hash_type(textSize));
@@ -38,9 +38,13 @@ hash_t ShadowText::hash() const {
     hash = JenkinsHashMix(hash, flags);
     hash = JenkinsHashMix(hash, android::hash_type(italicStyle));
     hash = JenkinsHashMix(hash, android::hash_type(scaleX));
-    hash = JenkinsHashMixShorts(hash, text, charCount);
-    for (uint32_t i = 0; i < charCount * 2; i++) {
-        hash = JenkinsHashMix(hash, android::hash_type(positions[i]));
+    if (text) {
+        hash = JenkinsHashMixShorts(hash, text, charCount);
+    }
+    if (positions) {
+        for (uint32_t i = 0; i < charCount * 2; i++) {
+            hash = JenkinsHashMix(hash, android::hash_type(positions[i]));
+        }
     }
     return JenkinsHashWhiten(hash);
 }