Force a copy when saving the NSData that came from another.

gminor7 · Jan 3, 2018 · 4588e6e · 4588e6e
1 parent 43caa38
commit 4588e6e
Showing 1 changed file with 6 additions and 1 deletion.
diff --git a/objectivec/GPBMessage.m b/objectivec/GPBMessage.m
@@ -2027,7 +2027,12 @@ - (void)parseMessageSet:(GPBCodedInputStream *)input
       [newInput release];
     } else {
       GPBUnknownFieldSet *unknownFields = GetOrMakeUnknownFields(self);
-      [unknownFields mergeMessageSetMessage:typeId data:rawBytes];
+      // rawBytes was created via a NoCopy, so it can be reusing a
+      // subrange of another NSData that might go out of scope as things
+      // unwind, so a copy is needed to ensure what is saved in the
+      // unknown fields stays valid.
+      NSData *cloned = [NSData dataWithData:rawBytes];
+      [unknownFields mergeMessageSetMessage:typeId data:cloned];
     }
   }
 }