nfsd_lookup_dentry exits with the parent filehandle locked. fh_put also
unlocks if necessary (nfsd filehandle locking is probably too lenient),
so it gets unlocked eventually, but if the following op in the compound
needs to lock it again, we can deadlock.
A fuzzer ran into this; normal clients don't send a secinfo followed by
a readdir in the same compound.
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).
Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This is basically a remote version of the btrfs CLONE operation,
so the implementation is fairly trivial. Made even more trivial
by stealing the XDR code and general framework Anna Schumaker's
COPY prototype.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This will be needed so COPY can look up the saved_fh in addition to the
current_fh.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In order to allow the client to make a sane determination of what
happened with racing LAYOUTGET/LAYOUTRETURN/CB_LAYOUTRECALL calls, we
must ensure that the seqids return accurately represent the order of
operations. The simplest way to do that is to ensure that operations on
a single stateid are serialized.
This patch adds a mutex to the layout stateid, and locks it when
checking the layout stateid's seqid. The mutex is held over the entire
operation and released after the seqid is bumped.
Note that in the case of CB_LAYOUTRECALL we must move the increment of
the seqid and setting into a new cb "prepare" operation. The lease
infrastructure will call the lm_break callback with a spinlock held, so
and we can't take the mutex in that codepath.
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
According to rfc5661 18.16.4,
"If EXCLUSIVE4_1 was used, the client determines the attributes
used for the verifier by comparing attrset with cva_attrs.attrmask;"
So, EXCLUSIVE4_1 also needs those bitmask used to store the verifier.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NLM locks don't conflict with NFSv4 share reservations, so we're not
going to learn anything new by watiting for them.
They do conflict with NFSv4 locks and with delegations.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
After proc_layoutcommit success, i_size_read(inode) always >= new_size.
Just set lc_size_chg before proc_layoutcommit, if proc_layoutcommit
failed, nfsd will skip the lc_size_chg, so it's no harm.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Remove the hack where we fput the read-specific file in generic code.
Instead we can do it in nfsd4_encode_read as that gets called for all
error cases as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This patch changes nfs4_preprocess_stateid_op so it always returns
a valid struct file if it has been asked for that. For that we
now allocate a temporary struct file for special stateids, and check
permissions if we got the file structure from the stateid. This
ensures that all callers will get their handling of special stateids
right, and avoids code duplication.
There is a little wart in here because the read code needs to know
if we allocated a file structure so that it can copy around the
read-ahead parameters. In the long run we should probably aim to
cache full file structures used with special stateids instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Pull fourth vfs update from Al Viro:
"d_inode() annotations from David Howells (sat in for-next since before
the beginning of merge window) + four assorted fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
RCU pathwalk breakage when running into a symlink overmounting something
fix I_DIO_WAKEUP definition
direct-io: only inc/dec inode->i_dio_count for file systems
fs/9p: fix readdir()
VFS: assorted d_backing_inode() annotations
VFS: fs/inode.c helpers: d_inode() annotations
VFS: fs/cachefiles: d_backing_inode() annotations
VFS: fs library helpers: d_inode() annotations
VFS: assorted weird filesystems: d_inode() annotations
VFS: normal filesystems (and lustre): d_inode() annotations
VFS: security/: d_inode() annotations
VFS: security/: d_backing_inode() annotations
VFS: net/: d_inode() annotations
VFS: net/unix: d_backing_inode() annotations
VFS: kernel/: d_inode() annotations
VFS: audit: d_backing_inode() annotations
VFS: Fix up some ->d_inode accesses in the chelsio driver
VFS: Cachefiles should perform fs modifications on the top layer only
VFS: AF_UNIX sockets should call mknod on the top layer only
If the client uses a special stateid then we'll pass a NULL file to
vfs_llseek.
Fixes: 24bab49122 " NFSD: Implement SEEK"
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: stable@vger.kernel.org
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
vfs_fallocate will hit a NULL dereference if the client tries an
ALLOCATE or DEALLOCATE with a special stateid. Fix that. (We also
depend on the open to have broken any conflicting leases or delegations
for us.)
(If it turns out we need to allow special stateid's then we could do a
temporary open here in the special-stateid case, as we do for read and
write. For now I'm assuming it's not necessary.)
Fixes: 95d871f03c "nfsd: Add ALLOCATE support"
Cc: stable@vger.kernel.org
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
NFS4_MAXLABELLEN has defined for sec label max length, use it directly.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
ALLOCATE/DEALLOCATE only reply one status value to client,
so, using nfsd4_only_status_rsize for reply size calculating.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Fix commit 9cf514ccfa (nfsd: implement pNFS operations).
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
For now just a few simple events to trace the layout stateid lifetime, but
these already were enough to find several bugs in the Linux client layout
stateid handling.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add support to issue layout recalls to clients. For now we only support
full-file recalls to get a simple and stable implementation. This allows
to embedd a nfsd4_callback structure in the layout_state and thus avoid
any memory allocations under spinlocks during a recall. For normal
use cases that do not intent to share a single file between multiple
clients this implementation is fully sufficient.
To ensure layouts are recalled on local filesystem access each layout
state registers a new FL_LAYOUT lease with the kernel file locking code,
which filesystems that support pNFS exports that require recalls need
to break on conflicting access patterns.
The XDR code is based on the old pNFS server implementation by
Andy Adamson, Benny Halevy, Boaz Harrosh, Dean Hildebrand, Fred Isaman,
Marc Eshel, Mike Sager and Ricardo Labiaga.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add support for the GETDEVICEINFO, LAYOUTGET, LAYOUTCOMMIT and
LAYOUTRETURN NFSv4.1 operations, as well as backing code to manage
outstanding layouts and devices.
Layout management is very straight forward, with a nfs4_layout_stateid
structure that extends nfs4_stid to manage layout stateids as the
top-level structure. It is linked into the nfs4_file and nfs4_client
structures like the other stateids, and contains a linked list of
layouts that hang of the stateid. The actual layout operations are
implemented in layout drivers that are not part of this commit, but
will be added later.
The worst part of this commit is the management of the pNFS device IDs,
which suffers from a specification that is not sanely implementable due
to the fact that the device-IDs are global and not bound to an export,
and have a small enough size so that we can't store the fsid portion of
a file handle, and must never be reused. As we still do need perform all
export authentication and validation checks on a device ID passed to
GETDEVICEINFO we are caught between a rock and a hard place. To work
around this issue we add a new hash that maps from a 64-bit integer to a
fsid so that we can look up the export to authenticate against it,
a 32-bit integer as a generation that we can bump when changing the device,
and a currently unused 32-bit integer that could be used in the future
to handle more than a single device per export. Entries in this hash
table are never deleted as we can't reuse the ids anyway, and would have
a severe lifetime problem anyway as Linux export structures are temporary
structures that can go away under load.
Parts of the XDR data, structures and marshaling/unmarshaling code, as
well as many concepts are derived from the old pNFS server implementation
from Andy Adamson, Benny Halevy, Dean Hildebrand, Marc Eshel, Fred Isaman,
Mike Sager, Ricardo Labiaga and many others.
Signed-off-by: Christoph Hellwig <hch@lst.de>
DEALLOCATE only returns a status value, meaning we can use the noop()
xdr encoder to reply to the client.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The ALLOCATE operation is used to preallocate space in a file. I can do
this by using vfs_fallocate() to do the actual preallocation.
ALLOCATE only returns a status indicator, so we don't need to write a
special encode() function.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Unknown operation numbers are caught in nfsd4_decode_compound() which
sets op->opnum to OP_ILLEGAL and op->status to nfserr_op_illegal. The
error causes the main loop in nfsd4_proc_compound() to skip most
processing. But nfsd4_proc_compound also peeks ahead at the next
operation in one case and doesn't take similar precautions there.
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We added this new estimator function but forgot to hook it up. The
effect is that NFSv4.1 (and greater) won't do zero-copy reads.
The estimate was also wrong by 8 bytes.
Fixes: ccae70a9ee "nfsd4: estimate sequence response size"
Cc: stable@vger.kernel.org
Reported-by: Chuck Lever <chucklever@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This patch adds server support for the NFS v4.2 operation SEEK, which
returns the position of the next hole or data segment in a file.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We don't want to rely on the client_mutex for protection in the case of
NFSv4 open owners. Instead, we add a mutex that will only be taken for
NFSv4.0 state mutating operations, and that will be released once the
entire compound is done.
Also, ensure that nfsd4_cstate_assign_replay/nfsd4_cstate_clear_replay
take a reference to the stateowner when they are using it for NFSv4.0
open and lock replay caching.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It's possible for nfsd to fail opening a file that it has just created.
When that happens, we throw a WARN but it doesn't include any info about
the error code. Print the status code to give us a bit more info.
Our QA group hit some of these warnings under some very heavy stress
testing. My suspicion is that they hit the file-max limit, but it's hard
to know for sure. Go ahead and add a -ENFILE mapping to
nfserr_serverfault to make the error more distinct (and correct).
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
lookup_clientid is preferable to find_confirmed_client since it's able
to use the cached client in the compound state.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Commit db2e747b14 (vfs: remove mode parameter from vfs_symlink())
have remove mode parameter from vfs_symlink.
So that, iattr isn't needed by nfsd_symlink now, just remove it.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The name of a link is currently stored in cr_name and cr_namelen, and
the content in cr_linkname and cr_linklen. That's confusing.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently nfsd_symlink has a weird hack to serve callers who don't
null-terminate symlink data: it looks ahead at the next byte to see if
it's zero, and copies it to a new buffer to null-terminate if not.
That means callers don't have to null-terminate, but they *do* have to
ensure that the byte following the end of the data is theirs to read.
That's a bit subtle, and the NFSv4 code actually got this wrong.
So let's just throw out that code and let callers pass null-terminated
strings; we've already fixed them to do that.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
An NFS operation that creates a new symlink includes the symlink data,
which is xdr-encoded as a length followed by the data plus 0 to 3 bytes
of zero-padding as required to reach a 4-byte boundary.
The vfs, on the other hand, wants null-terminated data.
The simple way to handle this would be by copying the data into a newly
allocated buffer with space for the final null.
The current nfsd_symlink code tries to be more clever by skipping that
step in the (likely) case where the byte following the string is already
0.
But that assumes that the byte following the string is ours to look at.
In fact, it might be the first byte of a page that we can't read, or of
some object that another task might modify.
Worse, the NFSv4 code tries to fix the problem by actually writing to
that byte.
In the NFSv2/v3 cases this actually appears to be safe:
- nfs3svc_decode_symlinkargs explicitly null-terminates the data
(after first checking its length and copying it to a new
page).
- NFSv2 limits symlinks to 1k. The buffer holding the rpc
request is always at least a page, and the link data (and
previous fields) have maximum lengths that prevent the request
from reaching the end of a page.
In the NFSv4 case the CREATE op is potentially just one part of a long
compound so can end up on the end of a page if you're unlucky.
The minimal fix here is to copy and null-terminate in the NFSv4 case.
The nfsd_symlink() interface here seems too fragile, though. It should
really either do the copy itself every time or just require a
null-terminated string.
Reported-by: Jeff Layton <jlayton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
sparse complains that we're stuffing non-byte-swapped values into
__be32's here. Since they're supposed to be opaque, it doesn't matter
much. Just add __force to make sparse happy.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Don't using cache_get besides export.h, using exp_get for export.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
rq_usedeferral and rq_splice_ok are used as 0 and 1, just defined to bool.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The rpc code makes available to the NFS server an array of pages to
encod into. The server represents its reply as an xdr buf, with the
head pointing into the first page in that array, the pages ** array
starting just after that, and the tail (if any) sharing any leftover
space in the page used by the head.
While encoding, we use xdr_stream->page_ptr to keep track of which page
we're currently using.
Currently we set xdr_stream->page_ptr to buf->pages, which makes the
head a weird exception to the rule that page_ptr always points to the
page we're currently encoding into. So, instead set it to buf->pages -
1 (the page actually containing the head), and remove the need for a
little unintuitive logic in xdr_get_next_encode_buffer() and
xdr_truncate_encode.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The memset of resp in svc_process_common should ensure that these are
already zeroed by the time they get here.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In the NFS4_OPEN_CLAIM_PREVIOUS case, we should only mark it confirmed
if the nfs4_check_open_reclaim check succeeds.
In the NFS4_OPEN_CLAIM_DELEG_PREV_FH and NFS4_OPEN_CLAIM_DELEGATE_PREV
cases, I see no point in declaring the openowner confirmed when the
operation is going to fail anyway, and doing so might allow the client
to game things such that it wouldn't need to confirm a subsequent open
with the same owner.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
RPC_MAX_AUTH_SIZE is scattered around several places. Better to set it
once in the auth code, where this kind of estimate should be made. And
while we're at it we can leave it zero when we're not using krb5i or
krb5p.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We plan to use this estimate to decide whether or not to allow zero-copy
reads. Currently we're assuming all getattr's are a page, which can be
both too small (ACLs e.g. may be arbitrarily long) and too large (after
an upcoming read patch this will unnecessarily prevent zero copy reads
in any read compound also containing a getattr).
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently we limit readdir results to a single page. This can result in
a performance regression compared to NFSv3 when reading large
directories.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It will turn out to be useful to have a more accurate estimate of reply
size; so, piggyback on the existing op reply-size estimators.
Also move nfsd4_max_reply to nfs4proc.c to get easier access to struct
nfsd4_operation and friends. (Thanks to Christoph Hellwig for pointing
out that simplification.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
I ran into this corner case in testing: in theory clients can provide
state owners up to 1024 bytes long. In the sessions case there might be
a risk of this pushing us over the DRC slot size.
The conflicting owner isn't really that important, so let's humor a
client that provides a small maxresponsize_cached by allowing ourselves
to return without the conflicting owner instead of outright failing the
operation.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
After this we can handle for example getattr of very large ACLs.
Read, readdir, readlink are still special cases with their own limits.
Also we can't handle a new operation starting close to the end of a
page.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Now that all op encoders can handle running out of space, we no longer
need to check the remaining size for every operation; only nonidempotent
operations need that check, and that can be done by
nfsd4_check_resp_size.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We've tried to prevent running out of space with COMPOUND_SLACK_SPACE
and special checking in those operations (getattr) whose result can vary
enormously.
However:
- COMPOUND_SLACK_SPACE may be difficult to maintain as we add
more protocol.
- BUG_ON or page faulting on failure seems overly fragile.
- Especially in the 4.1 case, we prefer not to fail compounds
just because the returned result came *close* to session
limits. (Though perfect enforcement here may be difficult.)
- I'd prefer encoding to be uniform for all encoders instead of
having special exceptions for encoders containing, for
example, attributes.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This is a cosmetic change for now; no change in behavior.
Note we're just depending on xdr_reserve_space to do the bounds checking
for us, we're not really depending on its adjustment of iovec or xdr_buf
lengths yet, as those are fixed up by as necessary after the fact by
read-link operations and by nfs4svc_encode_compoundres. However we do
have to update xdr->iov on read-like operations to prevent
xdr_reserve_space from messing with the already-fixed-up length of the
the head.
When the attribute encoding fails partway through we have to undo the
length adjustments made so far. We do it manually for now, but later
patches will add an xdr_truncate_encode() helper to handle cases like
this.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If nfsd4_check_resp_size() returns an error then we should really be
truncating the reply here, otherwise we may leave extra garbage at the
end of the rpc reply.
Also add a warning to catch any cases where our reply-size estimates may
be wrong in the case of a non-idempotent operation.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently if the nfs-level part of a reply would be too large, we'll
return an error to the client. But if the nfs-level part fits and
leaves no room for krb5p or krb5i stuff, then we just drop the request
entirely.
That's no good. Instead, reserve some slack space at the end of the
buffer and make sure we fail outright if we'd come close.
The slack space here is a massive overstimate of what's required, we
should probably try for a tighter limit at some point.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Just change the nfsd4_encode_getattr api. Not changing any code or
adding any new functionality yet.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This is a mechanical transformation with no change in behavior.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently a non-idempotent op reply may be cached if it fails in the
proc code but not if it fails at xdr decoding. I doubt there are any
xdr-decoding-time errors that would make this a problem in practice, so
this probably isn't a serious bug.
The space estimates should also take into account space required for
encoding of error returns. Again, not a practical problem, though it
would become one after future patches which will tighten the space
estimates.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
OP_MODIFIES_SOMETHING flags operations that we should be careful not to
initiate without being sure we have the buffer space to encode a reply.
None of these ops fall into that category.
We could probably remove a few more, but this isn't a very important
problem at least for ops whose reply size is easy to estimate.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Move the state locking and file descriptor reference out from the
callers and into nfs4_preprocess_stateid_op() itself.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Testing NFS4.0 by pynfs, I got some messeages as,
"nfsd: inode locked twice during operation."
When one compound RPC contains two or more ops that locks
the filehandle,the second op will cause the message.
As two SETATTR ops, after the first SETATTR, nfsd will not call
fh_put() to release current filehandle, it means filehandle have
unlocked with fh_post_saved = 1.
The second SETATTR find fh_post_saved = 1, and printk the message.
v2: introduce helper fh_clear_wcc().
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Pull nfsd updates from Bruce Fields:
- Handle some loose ends from the vfs read delegation support.
(For example nfsd can stop breaking leases on its own in a
fewer places where it can now depend on the vfs to.)
- Make life a little easier for NFSv4-only configurations
(thanks to Kinglong Mee).
- Fix some gss-proxy problems (thanks Jeff Layton).
- miscellaneous bug fixes and cleanup
* 'for-3.14' of git://linux-nfs.org/~bfields/linux: (38 commits)
nfsd: consider CLAIM_FH when handing out delegation
nfsd4: fix delegation-unlink/rename race
nfsd4: delay setting current_fh in open
nfsd4: minor nfs4_setlease cleanup
gss_krb5: use lcm from kernel lib
nfsd4: decrease nfsd4_encode_fattr stack usage
nfsd: fix encode_entryplus_baggage stack usage
nfsd4: simplify xdr encoding of nfsv4 names
nfsd4: encode_rdattr_error cleanup
nfsd4: nfsd4_encode_fattr cleanup
minor svcauth_gss.c cleanup
nfsd4: better VERIFY comment
nfsd4: break only delegations when appropriate
NFSD: Fix a memory leak in nfsd4_create_session
sunrpc: get rid of use_gssp_lock
sunrpc: fix potential race between setting use_gss_proxy and the upcall rpc_clnt
sunrpc: don't wait for write before allowing reads from use-gss-proxy file
nfsd: get rid of unused function definition
Define op_iattr for nfsd4_open instead using macro
NFSD: fix compile warning without CONFIG_NFSD_V3
...
If a file is unlinked or renamed between the time when we do the local
open and the time when we get the delegation, then we will return to the
client indicating that it holds a delegation even though the file no
longer exists under the name it was open under.
But a client performing an open-by-name, when it is returned a
delegation, must be able to assume that the file is still linked at the
name it was opened under.
So, hold the parent i_mutex for longer to prevent concurrent renames or
unlinks.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This is basically a no-op, to simplify a following patch.
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Remove the boilerplate code to marshall and unmarhall ACL objects into
xattrs and operate on the posix_acl objects directly. Also move all
the ACL handling code into nfs?acl.c where it belongs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
NFSv4 clients can contact port 2049 directly instead of needing the
portmapper.
Therefore a failure to register to the portmapper when starting an
NFSv4-only server isn't really a problem.
But Gareth Williams reports that an attempt to start an NFSv4-only
server without starting portmap fails:
#rpc.nfsd -N 2 -N 3
rpc.nfsd: writing fd to kernel failed: errno 111 (Connection refused)
rpc.nfsd: unable to set any sockets for nfsd
Add a flag to svc_version to tell the rpc layer it can safely ignore an
rpcbind failure in the NFSv4-only case.
Reported-by: Gareth Williams <gareth@garethwilliams.me.uk>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
commit 58cd57bfd9
"nfsd: Fix SP4_MACH_CRED negotiation in EXCHANGE_ID"
miss calculating the length of bitmap for spo_must_enforce and spo_must_allow.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
- don't BUG_ON() when not SP4_NONE
- calculate recv and send reserve sizes correctly
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
You can turn on or off support for minorversions using e.g.
echo "-4.2" >/proc/fs/nfsd/versions
However, the current implementation is a little wonky. For example, the
above will turn off 4.2 support, but it will also turn *on* 4.1 support.
This didn't matter as long as we only had 2 minorversions, which was
true till very recently.
And do a little cleanup here.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We saw a v4.0 client's create fail as follows:
- open create succeeds and gets a read delegation
- client attempts to set mode on new file, gets DELAY while
server recalls delegation.
- client attempts a CLAIM_DELEGATE_CUR open using the
delegation, gets error because of new file mode.
This probably can't happen on a recent kernel since we're no longer
giving out delegations on create opens. Nevertheless, it's a
bug--reclaim opens should bypass permission checks.
Reported-by: Steve Dickson <steved@redhat.com>
Reported-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Implement labeled NFS on the server: encoding and decoding, and writing
and reading, of file labels.
Enabled with CONFIG_NFSD_V4_SECURITY_LABEL.
Signed-off-by: Matthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: Miguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: Phua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: Khin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The Linux client is using CLAIM_FH to implement regular opens, not just
recovery cases, so it depends on the server to check permissions
correctly.
Therefore the owner override, which may make sense in the delegation
recovery case, isn't right in the CLAIM_FH case.
Symptoms: on a client with 49f9a0fafd
"NFSv4.1: Enable open-by-filehandle", Bryan noticed this:
touch test.txt
chmod 000 test.txt
echo test > test.txt
succeeding.
Cc: stable@kernel.org
Reported-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We're going out of our way here to remap an error to make rfc 3530
happy--but the rfc itself (nor rfc 1813, which has similar language)
gives no justification. And disagrees with local filesystem behavior,
with Linux and posix man pages, and knfsd's implemented behavior for v2
and v3.
And the documented behavior seems better, in that it gives a little more
information--you could implement the 3530 behavior using the posix
behavior, but not the other way around.
Also, the Linux client makes no attempt to remap this error in the v4
case, so it can end up just returning EEXIST to the application in a
case where it should return EISDIR.
So honestly I think the rfc's are just buggy here--or in any case it
doesn't see worth the trouble to remap this error.
Reported-by: Frank S Filz <ffilz@us.ibm.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Closed stateid's are kept around a little while to handle close replays
in the 4.0 case. So we stash them in the last-used stateid in the
oo_last_closed_stateid field of the open owner. We can free that in
encode_seqid_op_tail once the seqid on the open owner is next
incremented. But we don't want to do that on the close itself; so we
set NFS4_OO_PURGE_CLOSE flag set on the open owner, skip freeing it the
first time through encode_seqid_op_tail, then when we see that flag set
next time we free it.
This is unnecessarily baroque.
Instead, just move the logic that increments the seqid out of the xdr
code and into the operation code itself.
The justification given for the current placement is that we need to
wait till the last minute to be sure we know whether the status is a
sequence-id-mutating error or not, but examination of the code shows
that can't actually happen.
Reported-by: Yanchuan Nian <ycnian@gmail.com>
Tested-by: Yanchuan Nian <ycnian@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
we should return error status directly when nfs4_preprocess_stateid_op
return error.
Signed-off-by: fanchaoting <fanchaoting@cn.fujitsu.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If a client sets an owner (or group_owner or acl) attribute on open for
create, and the mapping of that owner to an id fails, then we return
BAD_OWNER. But BAD_OWNER is a seqid-mutating error, so we can't
shortcut the open processing that case: we have to at least look up the
owner so we can find the seqid to bump.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This BUG_ON just crashes the thread a little earlier than it would
otherwise--it doesn't seem useful.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It seems slightly simpler to make nfsd4_encode_fattr rather than its
callers responsible for advancing the write pointer on success.
(Also: the count == 0 check in the verify case looks superfluous.
Running out of buffer space is really the only reason fattr encoding
should fail with eresource.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
To ensure ordering of read data with any following operations, turn off
zero copy if the read is not the final operation in the compound.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This is simple: an NFSd service can be started at different times in
different network environments. So, its "boot time" has to be assigned
per net.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
With NFSv4, if we create a file then open it we explicit avoid checking
the permissions on the file during the open because the fact that we
created it ensures we should be allow to open it (the create and the
open should appear to be a single operation).
However if the reply to an EXCLUSIVE create gets lots and the client
resends the create, the current code will perform the permission check -
because it doesn't realise that it did the open already..
This patch should fix this.
Note that I haven't actually seen this cause a problem. I was just
looking at the code trying to figure out a different EXCLUSIVE open
related issue, and this looked wrong.
(Fix confirmed with pynfs 4.0 test OPEN4--bfields)
Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
[bfields: use OWNER_OVERRIDE and update for 4.1]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Our server rejects compounds containing more than one write operation.
It's unclear whether this is really permitted by the spec; with 4.0,
it's possibly OK, with 4.1 (which has clearer limits on compound
parameters), it's probably not OK. No client that we're aware of has
ever done this, but in theory it could be useful.
The source of the limitation: we need an array of iovecs to pass to the
write operation. In the worst case that array of iovecs could have
hundreds of elements (the maximum rwsize divided by the page size), so
it's too big to put on the stack, or in each compound op. So we instead
keep a single such array in the compound argument.
We fill in that array at the time we decode the xdr operation.
But we decode every op in the compound before executing any of them. So
once we've used that array we can't decode another write.
If we instead delay filling in that array till the time we actually
perform the write, we can reuse it.
Another option might be to switch to decoding compound ops one at a
time. I considered doing that, but it has a number of other side
effects, and I'd rather fix just this one problem for now.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This patch replaces init_net by SVC_NET(), where possible and also passes
proper context to nested functions where required.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Something like creating a client with setclientid and then trying to
confirm it with create_session may not crash the server, but I'm not
completely positive of that, and in any case it's obviously bad client
behavior.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
stateid_setter should be matched to op_set_currentstateid, rather than
op_get_currentstateid.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Passed network namespace replaced hard-coded init_net
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Pull nfsd bugfixes from J. Bruce Fields:
"One bugfix, and one minor header fix from Jeff Layton while we're
here"
* 'for-3.4' of git://linux-nfs.org/~bfields/linux:
nfsd: include cld.h in the headers_install target
nfsd: don't fail unchecked creates of non-special files
Allow a v3 unchecked open of a non-regular file succeed as if it were a
lookup; typically a client in such a case will want to fall back on a
local open, so succeeding and giving it the filehandle is more useful
than failing with nfserr_exist, which makes it appear that nothing at
all exists by that name.
Similarly for v4, on an open-create, return the same errors we would on
an attempt to open a non-regular file, instead of returning
nfserr_exist.
This fixes a problem found doing a v4 open of a symlink with
O_RDONLY|O_CREAT, which resulted in the current client returning EEXIST.
Thanks also to Trond for analysis.
Cc: stable@kernel.org
Reported-by: Orion Poplawski <orion@cora.nwra.com>
Tested-by: Orion Poplawski <orion@cora.nwra.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We'll need a way to flag the nfs4_client as already being recorded on
stable storage so that we don't continually upcall. Currently, that's
recorded in the cl_firststate field of the client struct. Using an
entire u32 to store a flag is rather wasteful though.
The cl_cb_flags field is only using 2 bits right now, so repurpose that
to a generic flags field. Rename NFSD4_CLIENT_KILL to
NFSD4_CLIENT_CB_KILL to make it evident that it's part of the callback
flags. Add a mask that we can use for existing checks that look to see
whether any flags are set, so that the new flags don't interfere.
Convert all references to cl_firstate to the NFSD4_CLIENT_STABLE flag,
and add a new NFSD4_CLIENT_RECLAIM_COMPLETE flag.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up due to code review.
The nfs4_verifier's data field is not guaranteed to be u32-aligned.
Casting an array of chars to a u32 * is considered generally
hazardous.
We can fix most of this by using a __be32 array to generate the
verifier's contents and then byte-copying it into the verifier field.
However, there is one spot where there is a backwards compatibility
constraint: the do_nfsd_create() call expects a verifier which is
32-bit aligned. Fix this spot by forcing the alignment of the create
verifier in the nfsd4_open args structure.
Also, sizeof(nfs4_verifer) is the size of the in-core verifier data
structure, but NFS4_VERIFIER_SIZE is the number of octets in an XDR'd
verifier. The two are not interchangeable, even if they happen to
have the same value.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
I get 320 bytes for struct svc_fh on x86_64, really a little large to be
putting on the stack; kmalloc() instead.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Compound processing stops on error, so the current filehandle won't be
used on error. Thus the order here doesn't really matter. It'll be
more convenient to do it later, though.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* 'for-3.3' of git://linux-nfs.org/~bfields/linux: (31 commits)
nfsd4: nfsd4_create_clid_dir return value is unused
NFSD: Change name of extended attribute containing junction
svcrpc: don't revert to SVC_POOL_DEFAULT on nfsd shutdown
svcrpc: fix double-free on shutdown of nfsd after changing pool mode
nfsd4: be forgiving in the absence of the recovery directory
nfsd4: fix spurious 4.1 post-reboot failures
NFSD: forget_delegations should use list_for_each_entry_safe
NFSD: Only reinitilize the recall_lru list under the recall lock
nfsd4: initialize special stateid's at compile time
NFSd: use network-namespace-aware cache registering routines
SUNRPC: create svc_xprt in proper network namespace
svcrpc: update outdated BKL comment
nfsd41: allow non-reclaim open-by-fh's in 4.1
svcrpc: avoid memory-corruption on pool shutdown
svcrpc: destroy server sockets all at once
svcrpc: make svc_delete_xprt static
nfsd: Fix oops when parsing a 0 length export
nfsd4: Use kmemdup rather than duplicating its implementation
nfsd4: add a separate (lockowner, inode) lookup
nfsd4: fix CONFIG_NFSD_FAULT_INJECTION compile error
...
A bunch of places in nfsd does mnt_{want,drop}_write on vfsmount of
export of given fhandle. Switched to obvious inlined helpers...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
With NFSv4.0 it was safe to assume that open-by-filehandles were always
reclaims.
With NFSv4.1 there are non-reclaim open-by-filehandle operations, so we
should ensure we're only insisting on reclaims in the
OPEN_CLAIM_PREVIOUS case.
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
According to rfc5661 18.50, implement DESTROY_CLIENTID operation.
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If we create the object and then return failure to the client, we're
left with an unexpected file in the filesystem.
I'm trying to eliminate such cases but not 100% sure I have so an
assertion might be helpful for now.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If process_open1() creates a new open owner, but the open later fails,
the current code will leave the open owner around. It won't be on the
close_lru list, and the client isn't expected to send a CLOSE, so it
will hang around as long as the client does.
Similarly, if process_open1() removes an existing open owner from the
close lru, anticipating that an open owner that previously had no
associated stateid's now will, but the open subsequently fails, then
we'll again be left with the same leak.
Fix both problems.
Reported-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
I'm not sure why I used a new field for this originally.
Also, the differences between some of these flags are a little subtle;
add some comments to explain.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
For checking the size of reply before calling a operation,
we need try to get maxsize of the operation's reply.
v3: using new method as Bruce said,
"we could handle operations in two different ways:
- For operations that actually change something (write, rename,
open, close, ...), do it the way we're doing it now: be
very careful to estimate the size of the response before even
processing the operation.
- For operations that don't change anything (read, getattr, ...)
just go ahead and do the operation. If you realize after the
fact that the response is too large, then return the error at
that point.
So we'd add another flag to op_flags: say, OP_MODIFIES_SOMETHING. And for
operations with OP_MODIFIES_SOMETHING set, we'd do the first thing. For
operations without it set, we'd do the second."
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
[bfields@redhat.com: crash, don't attempt to handle, undefined op_rsize_bop]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The stateowner has some fields that only make sense for openowners, and
some that only make sense for lockowners, and I find it a lot clearer if
those are separated out.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There are currently a couple races in the seqid replay code: a
retransmission could come while we're still encoding the original reply,
or a new seqid-mutating call could come as we're encoding a replay.
So, extend the state lock over the encoding (both encoding of a replayed
reply and caching of the original encoded reply).
I really hate doing this, and previously added the stateowner
reference-counting code to avoid it (which was insufficient)--but I
don't see a less complicated alternative at the moment.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The server is returning nfserr_resource for both permanent errors and
for errors (like allocation failures) that might be resolved by retrying
later. Save nfserr_resource for the former and use delay/jukebox for
the latter.
Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
A client that wants to execute a file must be able to read it. Read
opens over nfs are therefore implicitly allowed for executable files
even when those files are not readable.
NFSv2/v3 get this right by using a passed-in NFSD_MAY_OWNER_OVERRIDE on
read requests, but NFSv4 has gotten this wrong ever since
dc730e1737 "nfsd4: fix owner-override on
open", when we realized that the file owner shouldn't override
permissions on non-reclaim NFSv4 opens.
So we can't use NFSD_MAY_OWNER_OVERRIDE to tell nfsd_permission to allow
reads of executable files.
So, do the same thing we do whenever we encounter another weird NFS
permission nit: define yet another NFSD_MAY_* flag.
The industry's future standardization on 128-bit processors will be
motivated primarily by the need for integers with enough bits for all
the NFSD_MAY_* flags.
Reported-by: Leonardo Borda <leonardoborda@gmail.com>
Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The nfsd4 code has a bunch of special exceptions for error returns which
map nfserr_symlink to other errors.
In fact, the spec makes it clear that nfserr_symlink is to be preferred
over less specific errors where possible.
The patch that introduced it back in 2.6.4 is "kNFSd: correct symlink
related error returns.", which claims that these special exceptions are
represent an NFSv4 break from v2/v3 tradition--when in fact the symlink
error was introduced with v4.
I suspect what happened was pynfs tests were written that were overly
faithful to the (known-incomplete) rfc3530 error return lists, and then
code was fixed up mindlessly to make the tests pass.
Delete these unnecessary exceptions.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Fan Yong <yong.fan@whamcloud.com> noticed setting
FMODE_32bithash wouldn't work with nfsd v4, as
nfsd4_readdir() checks for 32 bit cookies. However, according to RFC 3530
cookies have a 64 bit type and cookies are also defined as u64 in
'struct nfsd4_readdir'. So remove the test for >32-bit values.
Cc: stable@kernel.org
Signed-off-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It's sort of ridiculous that we've never had a working reply cache for
NFSv4.
On the other hand, we may still not: our current reply cache is likely
not very good, especially in the TCP case (which is the only case that
matters for v4). What we really need here is some serious testing.
Anyway, here's a start.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Before nfs41 client's RECLAIM_COMPLETE done, nfs server should deny any
new locks or opens.
rfc5661:
" Whenever a client establishes a new client ID and before it does
the first non-reclaim operation that obtains a lock, it MUST send a
RECLAIM_COMPLETE with rca_one_fs set to FALSE, even if there are no
locks to reclaim. If non-reclaim locking operations are done before
the RECLAIM_COMPLETE, an NFS4ERR_GRACE error will be returned. "
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This operation is used by the client to check the validity of a list of
stateids.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This operation is used by the client to tell the server to free a
stateid.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
DESTROY_CLIENTID MAY be preceded with a SEQUENCE operation as long as
the client ID derived from the session ID of SEQUENCE is not the same
as the client ID to be destroyed. If the client IDs are the same,
then the server MUST return NFS4ERR_CLIENTID_BUSY.
(that's not implemented yet)
If DESTROY_CLIENTID is not prefixed by SEQUENCE, it MUST be the only
operation in the COMPOUND request (otherwise, the server MUST return
NFS4ERR_NOT_ONLY_OP).
This fixes the error return; before, we returned
NFS4ERR_OP_NOT_IN_SESSION; after this patch, we return NFS4ERR_NOTSUPP.
Signed-off-by: Benny Halevy <benny@tonian.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The NFS server uses nfsd_create_v3 to handle EXCLUSIVE4_1 opens, but
that function is not prepared to handle them.
Rename nfsd_create_v3() to do_nfsd_create(), and add handling of
EXCLUSIVE4_1.
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When PUTFH is followed by an operation that uses the filehandle, and
when the current client is using a security flavor that is inconsistent
with the given filehandle, we have a choice: we can return WRONGSEC
either when the current filehandle is set using the PUTFH, or when the
filehandle is first used by the following operation.
Follow the recommendations of RFC 5661 in making this choice.
(Our current behavior prevented the client from doing security
negotiation by returning WRONGSEC on PUTFH+SECINFO_NO_NAME.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The members of nfsd4_op_flags, (ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS)
equals to ALLOWED_AS_FIRST_OP, maybe that's not what we want.
OP_PUTROOTFH with op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
can't appears as the first operation with out SEQUENCE ops.
This patch modify the wrong value of ALLOWED_WITHOUT_FH etc which
was introduced by f9bb94c4.
Cc: stable@kernel.org
Reviewed-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
