Re: [PATCH] nfs client, kernel 2.4.31: readlink result overflow

[Peter Staubach <staubach@redhat.com>]

Assar wrote:

>Peter Staubach <staubach@redhat.com> writes:
>  
>
>>This code appears to assume that rcvbuf->page_base is zero here, but then
>>uses rcvbuf->page_base when calculating where to place the null byte.  It
>>seems to me that it should either use rcvbuf->page_base in both
>>calculations or neither.
>>    
>>
>
>The meaning of page_len and page_base are not totally clear to me.  Is
>it the case that the data starts at offset page_base and there is
>page_len bytes of it.  If that's the case, I think the code is doing
>the right thing.
>

I am not clear either, but I would think that kmap_atomic() would return
a pointer to the beginning of the page.  There is also an assumption that
there is only one page.  If page_base needs to be used to offset from
the address returned by kmap_atomic(), then I wouldn't think that the
current test is correct.  I think that it needs to take page_base into
account when checking for the boundary.

    Thanx...

       ps