NFSv4: Fix another bug in the close/open_downgrade code

James Drew reports another bug whereby the NFS client is now sending
an OPEN_DOWNGRADE in a situation where it should really have sent a
CLOSE: the client is opening the file for O_RDWR, but then trying to
do a downgrade to O_RDONLY, which is not allowed by the NFSv4 spec.

Reported-by: James Drews <drews@engr.wisc.edu>
Link: http://lkml.kernel.org/r/541AD7E5.8020409@engr.wisc.edu
Fixes: aee7af356e (NFSv4: Fix problems with close in the presence...)
Cc: stable@vger.kernel.org # 2.6.33+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This commit is contained in:
Trond Myklebust 2014-09-18 11:51:32 -04:00
parent 080af20cc9
commit cd9288ffae

View file

@ -2618,23 +2618,23 @@ static void nfs4_close_prepare(struct rpc_task *task, void *data)
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 */
calldata->arg.fmode = 0;
if (state->n_rdwr == 0) {
if (state->n_rdonly == 0) {
call_close |= is_rdonly || is_rdwr;
calldata->arg.fmode &= ~FMODE_READ;
}
if (state->n_wronly == 0) {
call_close |= is_wronly || is_rdwr;
calldata->arg.fmode &= ~FMODE_WRITE;
}
}
if (state->n_rdonly == 0)
call_close |= is_rdonly;
else if (is_rdonly)
calldata->arg.fmode |= FMODE_READ;
if (state->n_wronly == 0)
call_close |= is_wronly;
else if (is_wronly)
calldata->arg.fmode |= FMODE_WRITE;
} else if (is_rdwr)
calldata->arg.fmode |= FMODE_READ|FMODE_WRITE;
if (calldata->arg.fmode == 0)
call_close |= is_rdwr;
if (!nfs4_valid_open_stateid(state))
call_close = 0;
spin_unlock(&state->owner->so_lock);