From aee7af356e151494d5014f57b33460b162f181b5 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 25 Aug 2014 22:33:12 -0400 Subject: [PATCH] NFSv4: Fix problems with close in the presence of a delegation 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 calculate the initial 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 | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 75ae8d22f067..ff94a2f36051 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__); @@ -2608,18 +2609,24 @@ 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); + /* 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) { 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; } }