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    SubjectRe: [PATCH] netfilter: replace horrible hack with ksize()
    On Thu, 6 Mar 2008, Pekka J Enberg wrote:
    > > > - if (newlen >= ct->ext->real_len) {
    > > > + if (newlen >= ksize(ct->ext)) {
    > >
    > > This needs to look at the currently allocated size, otherwise
    > > it will always realloc when adding new extensions after having
    > > used up ksize(ct->ext) space.
    >
    > Lets say you
    >
    > p = kmalloc(8, ...);
    >
    > Then ksize(p) will return the currently allocated size which is 32 bytes
    > when page size is 4 KB, and not 8 bytes. So it should be equivalent of
    > what the current code does.
    >
    > What am I missing here?

    Ok, it's not equivalent. We have two sizes: object size (8 bytes) and
    buffer size (32 bytes) here. In netfilter, ->real_len is same as object
    size, not buffer size as ksize() is.

    But now I am officially even more confused, why does the netfilter code
    decided whether to reallocate based on _object size_ and not _buffer size_
    (as krealloc() does, for example)?

    Pekka


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