Re: [PATCH 2/2] x86: ia32_signal: remove unnecessary padding

[H. Peter Anvin]

Hiroshi Shimamoto wrote:
> H. Peter Anvin wrote:
>> Mikael Pettersson wrote:
>>> It does cause each signal delivery to leak 2 uninitialised
>>> kernel bytes to the end of retcode[], which seems unnecessary.
>> Not just unnecessary, it is a huge no-no for security.
> 
> Am I missing important thing?
> The frame->retcode is 8 bytes and packed structure with padding
> is 10 bytes each, and the code is copied to user stack 8 bytes only.
> 
> err |= __copy_to_user(frame->retcode, &code, 8);
> 
> I don't think the behavior is changed.
> 

Ah, nevermind, then.  Then it fine, obviously.

	-hpa
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/