From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756228Ab1HCXiw (ORCPT ); Wed, 3 Aug 2011 19:38:52 -0400 Received: from cantor2.suse.de ([195.135.220.15]:33902 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756214Ab1HCX3N (ORCPT ); Wed, 3 Aug 2011 19:29:13 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Aug 3 15:12:51 2011 Message-Id: <20110803221251.774246649@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 03 Aug 2011 15:01:37 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, "J. Bruce Fields" Subject: [077/102] nfsd4: fix file leak on open_downgrade In-Reply-To: <20110803221345.GA10346@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.0-stable review patch. If anyone has any objections, please let us know. ------------------ From: "J. Bruce Fields" commit f197c27196a5e7631b89e2e92daa096fcf7c302c upstream. Stateid's hold a read reference for a read open, a write reference for a write open, and an additional one of each for each read+write open. The latter wasn't getting put on a downgrade, so something like: open RW open R downgrade to R was resulting in a file leak. Also fix an imbalance in an error path. Regression from 7d94784293096c0a46897acdb83be5abd9278ece "nfsd4: fix downgrade/lock logic". Signed-off-by: J. Bruce Fields Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfs4state.c | 31 ++++++++----------------------- 1 file changed, 8 insertions(+), 23 deletions(-) --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -2332,15 +2332,6 @@ out: return ret; } -static inline void -nfs4_file_downgrade(struct nfs4_file *fp, unsigned int share_access) -{ - if (share_access & NFS4_SHARE_ACCESS_WRITE) - nfs4_file_put_access(fp, O_WRONLY); - if (share_access & NFS4_SHARE_ACCESS_READ) - nfs4_file_put_access(fp, O_RDONLY); -} - static void nfsd_break_one_deleg(struct nfs4_delegation *dp) { /* We're assuming the state code never drops its reference @@ -2627,7 +2618,7 @@ nfs4_upgrade_open(struct svc_rqst *rqstp status = nfsd4_truncate(rqstp, cur_fh, open); if (status) { if (new_access) { - int oflag = nfs4_access_to_omode(new_access); + int oflag = nfs4_access_to_omode(op_share_access); nfs4_file_put_access(fp, oflag); } return status; @@ -3385,18 +3376,15 @@ out: return status; } - -/* - * unset all bits in union bitmap (bmap) that - * do not exist in share (from successful OPEN_DOWNGRADE) - */ -static void -reset_union_bmap_access(unsigned long access, unsigned long *bmap) +static inline void nfs4_file_downgrade(struct nfs4_stateid *stp, unsigned int to_access) { int i; + for (i = 1; i < 4; i++) { - if ((i & access) != i) - __clear_bit(i, bmap); + if (test_bit(i, &stp->st_access_bmap) && !(i & to_access)) { + nfs4_file_put_access(stp->st_file, i); + __clear_bit(i, &stp->st_access_bmap); + } } } @@ -3417,7 +3405,6 @@ nfsd4_open_downgrade(struct svc_rqst *rq { __be32 status; struct nfs4_stateid *stp; - unsigned int share_access; dprintk("NFSD: nfsd4_open_downgrade on file %.*s\n", (int)cstate->current_fh.fh_dentry->d_name.len, @@ -3446,10 +3433,8 @@ nfsd4_open_downgrade(struct svc_rqst *rq stp->st_deny_bmap, od->od_share_deny); goto out; } - set_access(&share_access, stp->st_access_bmap); - nfs4_file_downgrade(stp->st_file, share_access & ~od->od_share_access); + nfs4_file_downgrade(stp, od->od_share_access); - reset_union_bmap_access(od->od_share_access, &stp->st_access_bmap); reset_union_bmap_deny(od->od_share_deny, &stp->st_deny_bmap); update_stateid(&stp->st_stateid);