Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx12.netapp.com ([216.240.18.77]:56286 "EHLO mx12.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753081AbaHZULP (ORCPT ); Tue, 26 Aug 2014 16:11:15 -0400 Message-ID: <53FCE9DF.1050407@Netapp.com> Date: Tue, 26 Aug 2014 16:11:11 -0400 From: Anna Schumaker MIME-Version: 1.0 To: Trond Myklebust , CC: James Drews , Subject: Re: [PATCH v2 1/2] NFSv4: Fix problems with close in the presence of a delegation References: <1409077853-15680-1-git-send-email-trond.myklebust@primarydata.com> In-Reply-To: <1409077853-15680-1-git-send-email-trond.myklebust@primarydata.com> Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: On 08/26/2014 02:30 PM, Trond Myklebust wrote: > In the presence of delegations, we can no longer assume that the > state->n_rdwr, state->n_rdonly, state->n_wronly reflect the open > stateid share mode, and so we need to need to calculate the initial Nit: Remove the duplicate "need to" (above). > value for calldata->arg.fmode using the state->flags. > > Reported-by: James Drews > Fixes: 88069f77e1ac5 (NFSv41: Fix a potential state leakage when...) > Cc: stable@vger.kernel.org # 2.6.33+ > Signed-off-by: Trond Myklebust > --- > fs/nfs/nfs4proc.c | 19 +++++++++++++------ > 1 file changed, 13 insertions(+), 6 deletions(-) > > diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c > index 75ae8d22f067..7d67d5b332d4 100644 > --- a/fs/nfs/nfs4proc.c > +++ b/fs/nfs/nfs4proc.c > @@ -2601,6 +2601,7 @@ static void nfs4_close_prepare(struct rpc_task *task, void *data) > struct nfs4_closedata *calldata = data; > struct nfs4_state *state = calldata->state; > struct inode *inode = calldata->inode; > + bool is_rdonly, is_wronly, is_rdwr; > int call_close = 0; > > dprintk("%s: begin!\n", __func__); > @@ -2608,24 +2609,30 @@ static void nfs4_close_prepare(struct rpc_task *task, void *data) > goto out_wait; > > task->tk_msg.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_OPEN_DOWNGRADE]; > - calldata->arg.fmode = FMODE_READ|FMODE_WRITE; > spin_lock(&state->owner->so_lock); > + is_rdwr = test_bit(NFS_O_RDWR_STATE, &state->flags); > + is_rdonly = test_bit(NFS_O_RDONLY_STATE, &state->flags); > + is_wronly = test_bit(NFS_O_WRONLY_STATE, &state->flags); > + spin_unlock(&state->owner->so_lock); > + /* Calculate the current open share mode */ > + calldata->arg.fmode = 0; > + if (is_rdonly || is_rdwr) > + calldata->arg.fmode |= FMODE_READ; > + if (is_wronly || is_rdwr) > + calldata->arg.fmode |= FMODE_WRITE; > /* Calculate the change in open mode */ > if (state->n_rdwr == 0) { Do we need the owner lock for reading state->n_rdwr, n_rdonly, and n_wronly? Anna > if (state->n_rdonly == 0) { > - call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags); > - call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags); > + call_close |= is_rdonly || is_rdwr; > calldata->arg.fmode &= ~FMODE_READ; > } > if (state->n_wronly == 0) { > - call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags); > - call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags); > + call_close |= is_wronly || is_rdwr; > calldata->arg.fmode &= ~FMODE_WRITE; > } > } > if (!nfs4_valid_open_stateid(state)) > call_close = 0; > - spin_unlock(&state->owner->so_lock); > > if (!call_close) { > /* Note: exit _without_ calling nfs4_close_done */