RFR(S): Crash with assert: symbol conversion failure in java_lang_String::create_from_symbol()
tobias.hartmann at oracle.com
Fri Sep 9 12:42:23 UTC 2016
please review the following patch:
The verification code in java_lang_String::create_from_symbol() that was added by Compact Strings fails because the input symbol does not contain valid UTF8. The problem is that a JCK JNI test passes an invalid UTF8 string as class name to the JNI method "FindClass". In fact, the string contains garbage from reading past array boundaries because of a bug in the test . The JNI spec  states that 'name' should be "a fully-qualified class name (that is, a package name, delimited by “/”, followed by the class name). If the name begins with “[“ (the array signature character), it returns an array class. The string is encoded in modified UTF-8".
I nevertheless think that we should not crash in the case of an invalid UTF8 string and therefore disabled the verification code with a comment. We did the same for java_lang_String::create_from_str() .
Tested with failing JCK test and JPRT (running).
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