Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753270AbdFSSgQ (ORCPT + 2 others); Mon, 19 Jun 2017 14:36:16 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:52253 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753248AbdFSSgM (ORCPT ); Mon, 19 Jun 2017 14:36:12 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Weston Andros Adamson , "J . Bruce Fields" , Anna Schumaker , Willy Tarreau Subject: [PATCH 3.10 161/268] NFSv4: fix getacl ERANGE for some ACL buffer sizes Date: Mon, 19 Jun 2017 20:31:00 +0200 Message-Id: <1497897167-14556-162-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1497897167-14556-1-git-send-email-w@1wt.eu> References: <1497897167-14556-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: From: Weston Andros Adamson commit ed92d8c137b7794c2c2aa14479298b9885967607 upstream. We're not taking into account that the space needed for the (variable length) attr bitmap, with the result that we'd sometimes get a spurious ERANGE when the ACL data got close to the end of a page. Just add in an extra page to make sure. Signed-off-by: Weston Andros Adamson Signed-off-by: J. Bruce Fields Signed-off-by: Anna Schumaker Signed-off-by: Willy Tarreau --- fs/nfs/nfs4proc.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index c2b89a1..c1148e8 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -4047,7 +4047,7 @@ out: */ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t buflen) { - struct page *pages[NFS4ACL_MAXPAGES] = {NULL, }; + struct page *pages[NFS4ACL_MAXPAGES + 1] = {NULL, }; struct nfs_getaclargs args = { .fh = NFS_FH(inode), .acl_pages = pages, @@ -4061,13 +4061,9 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu .rpc_argp = &args, .rpc_resp = &res, }; - unsigned int npages = DIV_ROUND_UP(buflen, PAGE_SIZE); + unsigned int npages = DIV_ROUND_UP(buflen, PAGE_SIZE) + 1; int ret = -ENOMEM, i; - /* As long as we're doing a round trip to the server anyway, - * let's be prepared for a page of acl data. */ - if (npages == 0) - npages = 1; if (npages > ARRAY_SIZE(pages)) return -ERANGE; -- 2.8.0.rc2.1.gbe9624a