On Wed, 30 Sep 2009 22:41:05 +0300 (EEST)
Julian Anastasov [off-list ref] wrote:

	Hello,

On Wed, 30 Sep 2009, Arjan van de Ven wrote:

quoted

fair enough; updated patch below

Later len can be checked
additionally and surely can exceed 128 (include/linux/ip_vs.h has
all user structures). 

the on-stack structure currently is 128 bytes though...

Can you show the exact cmd and len
used, may be there is error in some command or may be the
provided user structure is wrong?

this comes from code inspection using gcc features; this
is one of the (few) cases in the kernel where gcc cannot prove
that the copy_from_user() length for the copy-to-stack is sufficiently
bounds checked. I'm trying to make sure all these cases have
complete enough checks, both for the obvious security reasons but
also to be able to then make gcc emit a warning to prevent future
issues from popping up.



-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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