[Images] Bail out when GIF data is in unexpected format instead of crashing

ide · ide · commit 1ac74811b198 · 2015-02-26T07:49:06.000-08:00
Summary: 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. Closes facebook#77 Github Author: James Ide <ide@jameside.com> Test Plan: Imported from GitHub, without a `Test Plan:` line.
diff --git 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)) {

Original file line number	Diff line number	Diff line change
`@@ -446,6 +446,9 @@ + (CAKeyframeAnimation *)GIF:(id)json`
`446`	`446`	`}`
`447`	`447`
`448`	`448`	`imageSource = CGImageSourceCreateWithData((CFDataRef)data, NULL);`
	`449`	`+ } else {`
	`450`	`+ RCTLogMustFix(@"Expected NSString or NSData for GIF, received %@: %@", [json class], json);`
	`451`	`+ return nil;`
`449`	`452`	`}`
`450`	`453`
`451`	`454`	`if (!UTTypeConformsTo(CGImageSourceGetType(imageSource), kUTTypeGIF)) {`