From 00ecaa8aec77ea9bd67a97fd76a37d0d82e54d5f Mon Sep 17 00:00:00 2001
From: James Ide <ide@jameside.com>
Date: Tue, 17 Feb 2015 14:55:07 -0800
Subject: [PATCH] [Images] Bail out when GIF data is in unexpected format
 instead of crashing

When the GIF data is not a string nor NSData, `imageSource` is some unknown value set to whatever memory was on the stack. Calling `CGImageSourceGetType` on it has undefined behavior, and if it makes through to the CFRelease (maybe because it is NULL) then CFRelease will crash. This fixes a clang warning.
---
 ReactKit/Base/RCTConvert.m | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/ReactKit/Base/RCTConvert.m b/ReactKit/Base/RCTConvert.m
index 752d03ced0bde9..ab79cd8617742b 100644
--- a/ReactKit/Base/RCTConvert.m
+++ b/ReactKit/Base/RCTConvert.m
@@ -446,6 +446,9 @@ + (CAKeyframeAnimation *)GIF:(id)json
     }
 
     imageSource = CGImageSourceCreateWithData((CFDataRef)data, NULL);
+  } else {
+      RCTLogMustFix(@"Expected NSString or NSData for GIF, received %@: %@", [json class], json);
+      return nil;
   }
 
   if (!UTTypeConformsTo(CGImageSourceGetType(imageSource), kUTTypeGIF)) {