Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933628AbaJDA0n (ORCPT ); Fri, 3 Oct 2014 20:26:43 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:45325 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755968AbaJCVnB (ORCPT ); Fri, 3 Oct 2014 17:43:01 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "J. Bruce Fields" Subject: [PATCH 3.16 155/357] nfsd4: fix rd_dircount enforcement Date: Fri, 3 Oct 2014 14:29:01 -0700 Message-Id: <20141003212938.124166492@linuxfoundation.org> X-Mailer: git-send-email 2.1.2 In-Reply-To: <20141003212933.458851516@linuxfoundation.org> References: <20141003212933.458851516@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: "J. Bruce Fields" commit aee3776441461c14ba6d8ed9e2149933e65abb6e upstream. Commit 3b299709091b "nfsd4: enforce rd_dircount" totally misunderstood rd_dircount; it refers to total non-attribute bytes returned, not number of directory entries returned. Bring the code into agreement with RFC 3530 section 14.2.24. Fixes: 3b299709091b "nfsd4: enforce rd_dircount" Signed-off-by: J. Bruce Fields Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfs4xdr.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2662,6 +2662,7 @@ nfsd4_encode_dirent(void *ccdv, const ch struct xdr_stream *xdr = cd->xdr; int start_offset = xdr->buf->len; int cookie_offset; + u32 name_and_cookie; int entry_bytes; __be32 nfserr = nfserr_toosmall; __be64 wire_offset; @@ -2723,7 +2724,14 @@ nfsd4_encode_dirent(void *ccdv, const ch cd->rd_maxcount -= entry_bytes; if (!cd->rd_dircount) goto fail; - cd->rd_dircount--; + /* + * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so + * let's always let through the first entry, at least: + */ + name_and_cookie = 4 * XDR_QUADLEN(namlen) + 8; + if (name_and_cookie > cd->rd_dircount && cd->cookie_offset) + goto fail; + cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie); cd->cookie_offset = cookie_offset; skip_entry: cd->common.err = nfs_ok; @@ -3333,6 +3341,10 @@ nfsd4_encode_readdir(struct nfsd4_compou } maxcount = min_t(int, maxcount-16, bytes_left); + /* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */ + if (!readdir->rd_dircount) + readdir->rd_dircount = INT_MAX; + readdir->xdr = xdr; readdir->rd_maxcount = maxcount; readdir->common.err = 0; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/