From 445cb8df9a966543d45f72b37e7582190f81fbf2 Mon Sep 17 00:00:00 2001
From: Sergei Dryganets <sergeyd@microsoft.com>
Date: Fri, 4 Aug 2017 03:32:52 +0000
Subject: [PATCH] LocalString doesn't have a check for nullptr which could 
 cause a crash if nullptr passed.

LocalString doesn't have a check for nullptr which causes a crash if null string passed
---
 .../jni/first-party/fb/jni/LocalString.cpp    | 22 ++++++++++---------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/ReactAndroid/src/main/jni/first-party/fb/jni/LocalString.cpp b/ReactAndroid/src/main/jni/first-party/fb/jni/LocalString.cpp
index 6827ec282d19cb..7e60d2642300c4 100644
--- a/ReactAndroid/src/main/jni/first-party/fb/jni/LocalString.cpp
+++ b/ReactAndroid/src/main/jni/first-party/fb/jni/LocalString.cpp
@@ -82,16 +82,18 @@ size_t modifiedLength(const uint8_t* str, size_t* length) {
   // NUL-terminated: Scan for length and supplementary characters
   size_t i = 0;
   size_t j = 0;
-  while (str[i] != 0) {
-    if (str[i + 1] == 0 ||
-        str[i + 2] == 0 ||
-        str[i + 3] == 0 ||
-        !isFourByteUTF8Encoding(&(str[i]))) {
-      i += 1;
-      j += 1;
-    } else {
-      i += 4;
-      j += 6;
+  if (str != nullptr) {
+    while (str[i] != 0) {
+      if (str[i + 1] == 0 ||
+          str[i + 2] == 0 ||
+          str[i + 3] == 0 ||
+          !isFourByteUTF8Encoding(&(str[i]))) {
+        i += 1;
+        j += 1;
+      } else {
+        i += 4;
+        j += 6;
+      }
     }
   }