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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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