Suggestion on "int len" sanity

[XIAO Gang <xiao@unice.fr>]

I would like to make a security suggestion.

There are many length variables in the kernel, locally declared as "len" 
or "length", either as "int", "unsigned int" or "size_t". However, 
declaring a length as "int" leads easily to an erroneous situation, as 
the author (or even a code checker) might make the implicite hypothesis 
that the length is positive, so that it is enough to make a sanity check 
of the kind

if (length > limit) ERROR;

which is not enough.

On the other hand, when a variable is named "len" or "length", it is 
usually used for length and never should go negative. So could I suggest 
that the declarations of these variables to be uniformized to "size_t", 
via a gradual but sysmatic cleanup?

--

XIAO Gang (~{P$8U~})                          xiao@unice.fr
         home page: pcmath126.unice.fr/xiao.html 



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