Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx12.netapp.com ([216.240.18.77]:32996 "EHLO mx12.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751036Ab3LJUKj convert rfc822-to-8bit (ORCPT ); Tue, 10 Dec 2013 15:10:39 -0500 From: Weston Andros Adamson To: Trond Myklebust CC: linux-nfs list Subject: Re: [PATCH v2] NFSv4: fix getacl ERANGE for some ACL buffer sizes Date: Tue, 10 Dec 2013 20:10:38 +0000 Message-ID: <9C456209-7EDE-4494-9651-903E6A4E7055@netapp.com> References: <1385068813-5491-1-git-send-email-dros@netapp.com> <1386699230.2879.26.camel@leira.trondhjem.org> <1556485E-F391-4F58-AEE3-07C829DA2DB1@netapp.com> <838C6973-AF5C-4B33-B673-B7DD2B810628@primarydata.com> In-Reply-To: <838C6973-AF5C-4B33-B673-B7DD2B810628@primarydata.com> Content-Type: text/plain; charset="Windows-1252" MIME-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org List-ID: On Dec 10, 2013, at 2:19 PM, Trond Myklebust wrote: > > On Dec 10, 2013, at 21:11, Weston Andros Adamson wrote: > >> >> On Dec 10, 2013, at 1:13 PM, Trond Myklebust wrote: >> >>> On Thu, 2013-11-21 at 16:20 -0500, Weston Andros Adamson wrote: >> >>> >>>> if (res.acl_scratch) >>>> diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c >>>> index 5be2868..4e2e2da 100644 >>>> --- a/fs/nfs/nfs4xdr.c >>>> +++ b/fs/nfs/nfs4xdr.c >>>> @@ -5207,8 +5207,6 @@ static int decode_getacl(struct xdr_stream *xdr, struct rpc_rqst *req, >>>> if ((status = decode_op_hdr(xdr, OP_GETATTR)) != 0) >>>> goto out; >>>> >>>> - xdr_enter_page(xdr, xdr->buf->page_len); >>> >>> Why is this being removed? >> >> Because it BUG()s! ;) >> >> I must admit that I don?t get why xdr_enter_page() doesn?t work when the XDR layer does the page allocation, but it does not ? and the nfs3xdr ACL code (which uses the XDR layer allocation) also doesn?t call this. It worked well without this, so I just removed it and didn?t investigate why. > > I?m guessing that xdr->buf>page_len is being set incorrectly by the code that does the page allocation and/or that it is failing to update xdr->buf->len and/or xdr->buf->buflen. > > We really do need the xdr_enter_page() here, or the acl bitmap + data won?t be aligned properly on the page boundary. Ok, I?ll add that back and then fix the oops? and investigate if the v3 ACL code needs it too? Thanks, -dros