Re: Infinite loop

[Michael Koch]

On Wed, Nov 16, 2005 at 11:56:37AM +0000, Gary Benson wrote:
> I found a bug where the thing that throws SecurityExceptions can
> itself cause a SecurityException to be thrown causing an infinite
> loop.
> 
> When java.security.AccessControlContext.checkPermission decides that a
> permission is denied it throws the exception with the following line:
> 
>   throw new AccessControlException ("permission "
>                                     + perm
>                                     + " not granted: "
>                                     + domain
>                                     + " does not imply it.");
> 
> Where "domain" is a java.security.ProtectionDomain, whose toString()
> method calls System.getProperty("line.separator").  If your security
> policy denies read access to that system property then it's going to
> end up trying to throw the same AccessControlException and failing to
> access line.separator again, ad infinitum (until you run out of
> stack).
> 
> I wasn't sure quite how best to fix this so I haven't made a patch.

The solution is to use gnu.classpath.SystemProperties.getProperty(...).
This does no security check. It is exactly for such issues.


Cheers,
Michael
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