From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "J. Bruce Fields" Subject: [PATCH 3.12 073/116] nfsd4: fix xdr decoding of large non-write compounds Date: Tue, 26 Nov 2013 16:57:26 -0800 Message-Id: <20131127005741.976497395@linuxfoundation.org> In-Reply-To: <20131127005736.915454872@linuxfoundation.org> References: <20131127005736.915454872@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: "J. Bruce Fields" commit 365da4adebb1c012febf81019ad3dc5bb52e2a13 upstream. This fixes a regression from 247500820ebd02ad87525db5d9b199e5b66f6636 "nfsd4: fix decoding of compounds across page boundaries". The previous code was correct: argp->pagelist is initialized in nfs4svc_deocde_compoundargs to rqstp->rq_arg.pages, and is therefore a pointer to the page *after* the page we are currently decoding. The reason that patch nevertheless fixed a problem with decoding compounds containing write was a bug in the write decoding introduced by 5a80a54d21c96590d013378d8c5f65f879451ab4 "nfsd4: reorganize write decoding", after which write decoding no longer adhered to the rule that argp->pagelist point to the next page. Signed-off-by: J. Bruce Fields Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfs4xdr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -141,8 +141,8 @@ xdr_error: \ static void next_decode_page(struct nfsd4_compoundargs *argp) { - argp->pagelist++; argp->p = page_address(argp->pagelist[0]); + argp->pagelist++; if (argp->pagelen < PAGE_SIZE) { argp->end = argp->p + (argp->pagelen>>2); argp->pagelen = 0; @@ -1209,6 +1209,7 @@ nfsd4_decode_write(struct nfsd4_compound len -= pages * PAGE_SIZE; argp->p = (__be32 *)page_address(argp->pagelist[0]); + argp->pagelist++; argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE); } argp->p += XDR_QUADLEN(len);