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    SubjectRe: [PATCH] NFS: nfsaclsvc_encode_getaclres() - Fix potential NULL deref and tiny optimization.
    On Fri, 27 Oct 2006, Jesper Juhl wrote:

    > In fs/nfsd/nfs2acl.c::nfsaclsvc_encode_getaclres() I see a few issues.
    >
    > 1) At the top of the function we assign to the 'inode' variable by
    > dereferencing 'dentry', but further down we test 'dentry' for NULL. So, if
    > 'dentry' (which is really 'resp->fh.fh_dentry') can be NULL, then either
    > we have a potential NULL pointer deref bug or we have a superflous test.
    >

    resp->fh.fh_dentry cannot be NULL on nfsaclsvc_encode_getaclres so the
    early assignment is appropriate for both *dentry and *inode. *inode will
    need to be checked for NULL in the conditional, however, and return 0 on
    true.

    > 3) There are two locations in the function where we may return before we
    > use the value of the variable 'w', but we compute it at the very top of the
    > function. So in the case where we return early we have wasted a few cycles
    > computing a value that was never used.
    >

    w should be an unsigned int.

    David
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