[Patch] PR java/22113: Fix buffer overflow in Java lexer for FP literals

[Andrew Haley]

David Daney writes:
 > Ranjit Mathew wrote:
 > > Hi,
 > > 
 > >   This is a naive but effective patch for PR java/22113 where
 > > the 'literal_token' buffer of do_java_lex() in lex.c for reading
 > > in an FP literal was overflowing in cases like the Jacks testcase
 > > 3.10.2-round-6.
 > > 
 > > Tested on i686-pc-linux-gnu with Jacks included. Produces
 > > no new failures and fixes the recent FAIL-ing of 3.10.2-round-6
 > > on i686-pc-linux-gnu at least.
 > > 
 > > OK for mainline?
 > > 
 > > Thanks,
 > > Ranjit.
 > > 
 > > :ADDPATCH java:
 > > 
 > > 
 > > 
 > > ------------------------------------------------------------------------
 > > 
 > > Index: ChangeLog
 > > from  Ranjit Mathew  <rmathew@hotmail.com>
 > > 
 > > 	PR java/22113
 > > 	* lex.c (do_java_lex): Define MAX_TOKEN_LEN. Avoid overflowing
 > > 	`literal_token' for large numeric input tokens.
 > > 
 > 
 > What is the actual length of the longest of the tokens in question 
 > allowed by the JLS?
 > 
 > It seems if it is unbounded, that this is not the correct fix. 
 > Otherwise it seems unlikely that the upper bound is exactly 256.

Sure, but it's better than what it replaces.

Andrew.