From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:59452 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751107AbdBWTyX (ORCPT ); Thu, 23 Feb 2017 14:54:23 -0500 Date: Thu, 23 Feb 2017 14:54:21 -0500 From: "J. Bruce Fields" To: Anna Schumaker Cc: Weston Andros Adamson , Trond Myklebust , Anna Schumaker , linux-nfs list , Andreas Gruenbacher , Weston Andros Adamson Subject: [PATCH 2/2] NFSv4: fix getacl ERANGE for some ACL buffer sizes Message-ID: <20170223195420.GH9417@parsley.fieldses.org> References: <1487470070-32358-1-git-send-email-bfields@redhat.com> <1487470070-32358-3-git-send-email-bfields@redhat.com> <261D4020-D9E4-4F1E-81CF-11EAAEABA684@primarydata.com> <20170222223656.GG24122@parsley.fieldses.org> <6606b2d5-719f-9e27-6f95-eec8cebfb1a8@gmail.com> <20170223194321.GF9417@parsley.fieldses.org> <20170223195338.GG9417@parsley.fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20170223195338.GG9417@parsley.fieldses.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: From: Weston Andros Adamson 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 Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields --- 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 0a0eaecf9676..60501e10625d 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -5069,7 +5069,7 @@ static void nfs4_write_cached_acl(struct inode *inode, struct page **pages, size */ 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, @@ -5083,13 +5083,9 @@ 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; -- 2.9.3