Move the existing static function to an inline helper, and call it.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The maximum size of a backchannel message on RPC-over-RDMA depends
on the connection's inline threshold. Today that threshold is
typically 1024 bytes, making the maximum message size 996 bytes.
The Linux server's CREATE_SESSION operation checks that the size
of callback Calls can be as large as 1044 bytes, to accommodate
RPCSEC_GSS. Thus CREATE_SESSION fails if a client advertises the
true message size maximum of 996 bytes.
But the server's backchannel currently does not support RPCSEC_GSS.
The actual maximum size it needs is much smaller. It is safe to
reduce the limit to enable NFSv4.1 on RDMA backchannel operation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The server does indeed now support NFSv4.1 on RDMA transports. It
does not support shifting an RDMA-capable TCP transport (such as
iWARP) to RDMA mode.
Reported-by: Shirley Ma <shirley.ma@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Remember free allocated client when meeting unsupported state protect how.
Fixes: 50c7b948ad ("nfsd: minor consolidation of mach_cred handling code")
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
kerberized NFSv4.1 mounts, and Scott Mayhew's work addressing ACK storms
that can affect some high-availability NFS setups.
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Merge tag 'nfsd-4.5' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Smaller bugfixes and cleanup, including a fix for a failures of
kerberized NFSv4.1 mounts, and Scott Mayhew's work addressing ACK
storms that can affect some high-availability NFS setups"
* tag 'nfsd-4.5' of git://linux-nfs.org/~bfields/linux:
nfsd: add new io class tracepoint
nfsd: give up on CB_LAYOUTRECALLs after two lease periods
nfsd: Fix nfsd leaks sunrpc module references
lockd: constify nlmsvc_binding structure
lockd: use to_delayed_work
nfsd: use to_delayed_work
Revert "svcrdma: Do not send XDR roundup bytes for a write chunk"
lockd: Register callbacks on the inetaddr_chain and inet6addr_chain
nfsd: Register callbacks on the inetaddr_chain and inet6addr_chain
sunrpc: Add a function to close temporary transports immediately
nfsd: don't base cl_cb_status on stale information
nfsd4: fix gss-proxy 4.1 mounts for some AD principals
nfsd: fix unlikely NULL deref in mach_creds_match
nfsd: minor consolidation of mach_cred handling code
nfsd: helper for dup of possibly NULL string
svcrpc: move some initialization to common code
nfsd: fix a warning message
nfsd: constify nfsd4_callback_ops structure
nfsd: recover: constify nfsd4_client_tracking_ops structures
svcrdma: Do not send XDR roundup bytes for a write chunk
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>
The principal name on a gss cred is used to setup the NFSv4.0 callback,
which has to have a client principal name to authenticate to.
That code wants the name to be in the form servicetype@hostname.
rpc.svcgssd passes down such names (and passes down no principal name at
all in the case the principal isn't a service principal).
gss-proxy always passes down the principal name, and passes it down in
the form servicetype/hostname@REALM. So we've been munging the name
gss-proxy passes down into the format the NFSv4.0 callback code expects,
or throwing away the name if we can't.
Since the introduction of the MACH_CRED enforcement in NFSv4.1, we've
also been using the principal name to verify that certain operations are
done as the same principal as was used on the original EXCHANGE_ID call.
For that application, the original name passed down by gss-proxy is also
useful.
Lack of that name in some cases was causing some kerberized NFSv4.1
mount failures in an Active Directory environment.
This fix only works in the gss-proxy case. The fix for legacy
rpc.svcgssd would be more involved, and rpc.svcgssd already has other
problems in the AD case.
Reported-and-tested-by: James Ralston <ralston@pobox.com>
Acked-by: Simo Sorce <simo@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We really shouldn't allow a client to be created with cl_mach_cred set
unless it also has a principal name.
This also allows us to fail such cases immediately on EXCHANGE_ID as
opposed to waiting and incorrectly returning WRONG_CRED on the following
CREATE_SESSION.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Technically the initialization in the NULL case isn't even needed as the
only caller already has target zeroed out, but it seems safer to keep
copy_cred generic.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The WARN() macro takes a condition and a format string. The condition
was accidentally left out here so it just prints the function name
instead of the message.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The nfsd4_callback_ops structure is never modified, so declare it as const.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We observed multiple open stateids on the server for files that
seemingly should have been closed.
nfsd4_process_open2() tests for the existence of a preexisting
stateid. If one is not found, the locks are dropped and a new
one is created. The problem is that init_open_stateid(), which
is also responsible for hashing the newly initialized stateid,
doesn't check to see if another open has raced in and created
a matching stateid. This fix is to enable init_open_stateid() to
return the matching stateid and have nfsd4_process_open2()
swap to that stateid and switch to the open upgrade path.
In testing this patch, coverage to the newly created
path indicates that the race was indeed happening.
Signed-off-by: Andrew Elble <aweits@rit.edu>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We've observed the nfsd server in a state where there are
multiple delegations on the same nfs4_file for the same client.
The nfs client does attempt to DELEGRETURN these when they are presented to
it - but apparently under some (unknown) circumstances the client does not
manage to return all of them. This leads to the eventual
attempt to CB_RECALL more than one delegation with the same nfs
filehandle to the same client. The first recall will succeed, but the
next recall will fail with NFS4ERR_BADHANDLE. This leads to the server
having delegations on cl_revoked that the client has no way to FREE
or DELEGRETURN, with resulting inability to recover. The state manager
on the server will continually assert SEQ4_STATUS_RECALLABLE_STATE_REVOKED,
and the state manager on the client will be looping unable to satisfy
the server.
List discussion also reports a race between OPEN and DELEGRETURN that
will be avoided by only sending the delegation once to the
client. This is also logically in accordance with RFC5561 9.1.1 and 10.2.
So, let's:
1.) Not hand out duplicate delegations.
2.) Only send them to the client once.
RFC 5561:
9.1.1:
"Delegations and layouts, on the other hand, are not associated with a
specific owner but are associated with the client as a whole
(identified by a client ID)."
10.2:
"...the stateid for a delegation is associated with a client ID and may be
used on behalf of all the open-owners for the given client. A
delegation is made to the client as a whole and not to any specific
process or thread of control within it."
Reported-by: Eric Meddaugh <etmsys@rit.edu>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Olga Kornievskaia <aglo@umich.edu>
Signed-off-by: Andrew Elble <aweits@rit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Bruce points out that the increment of the seqid in stateids is not
serialized in any way, so it's possible for racing calls to bump it
twice and end up sending the same stateid. While we don't have any
reports of this problem it _is_ theoretically possible, and could lead
to spurious state recovery by the client.
In the current code, update_stateid is always followed by a memcpy of
that stateid, so we can combine the two operations. For better
atomicity, we add a spinlock to the nfs4_stid and hold that when bumping
the seqid and copying the stateid.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
At least in the v4.0 case openowners can hang around for a while after
last close, but they shouldn't really block (for example), a new mount
with a different principal.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In bakeathon testing Solaris client was getting CLID_INUSE error when
doing a krb5 mount soon after an auth_sys mount, or vice versa.
That's not really necessary since in this case the old client doesn't
have any state any more:
http://tools.ietf.org/html/rfc7530#page-103
"when the server gets a SETCLIENTID for a client ID that
currently has no state, or it has state but the lease has
expired, rather than returning NFS4ERR_CLID_INUSE, the server
MUST allow the SETCLIENTID and confirm the new client ID if
followed by the appropriate SETCLIENTID_CONFIRM."
This doesn't fix the problem completely since our client_has_state()
check counts openowners left around to handle close replays, which we
should probably just remove in this case.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Andrew was seeing a race occur when an OPEN and OPEN_DOWNGRADE were
running in parallel. The server would receive the OPEN_DOWNGRADE first
and check its seqid, but then an OPEN would race in and bump it. The
OPEN_DOWNGRADE would then complete and bump the seqid again. The result
was that the OPEN_DOWNGRADE would be applied after the OPEN, even though
it should have been rejected since the seqid changed.
The only recourse we have here I think is to serialize operations that
bump the seqid in a stateid, particularly when we're given a seqid in
the call. To address this, we add a new rw_semaphore to the
nfs4_ol_stateid struct. We do a down_write prior to checking the seqid
after looking up the stateid to ensure that nothing else is going to
bump it while we're operating on it.
In the case of OPEN, we do a down_read, as the call doesn't contain a
seqid. Those can run in parallel -- we just need to serialize them when
there is a concurrent OPEN_DOWNGRADE or CLOSE.
LOCK and LOCKU however always take the write lock as there is no
opportunity for parallelizing those.
Reported-and-Tested-by: Andrew W Elble <aweits@rit.edu>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We have observed the server sending recalls for delegation stateids
that have already been successfully returned. Change
nfsd4_cb_recall_done() to return success if the client has returned
the delegation. While this does not completely eliminate the sending
of recalls for delegations that have already been returned, this
does prevent unnecessarily declaring the callback path to be down.
Reported-by: Eric Meddaugh <etmsys@rit.edu>
Signed-off-by: Andrew Elble <aweits@rit.edu>
Acked-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Somebody with a Solaris client was hitting this case. We haven't
figured out why yet, and don't have a reproducer. Meanwhile Frank
noticed that RFC 7530 actually recommends CLID_INUSE for this case.
Unlikely to help the original reporter, but may as well fix it.
Reported-by: Frank Filz <ffilzlnx@mindspring.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It's possible that a DELEGRETURN could race with (e.g.) client expiry,
in which case we could end up putting the delegation hash reference more
than once.
Have unhash_delegation_locked return a bool that indicates whether it
was already unhashed. In the case of destroy_delegation we only
conditionally put the hash reference if that returns true.
The other callers of unhash_delegation_locked call it while walking
list_heads that shouldn't yet be detached. If we find that it doesn't
return true in those cases, then throw a WARN_ON as that indicates that
we have a partially hashed delegation, and that something is likely very
wrong.
Tested-by: Andrew W Elble <aweits@rit.edu>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When an open or lock stateid is hashed, we take an extra reference to
it. When we unhash it, we drop that reference. The code however does
not properly account for the case where we have two callers concurrently
trying to unhash the stateid. This can lead to list corruption and the
hash reference being put more than once.
Fix this by having unhash_ol_stateid use list_del_init on the st_perfile
list_head, and then testing to see if that list_head is empty before
releasing the hash reference. This means that some of the unhashing
wrappers now become bool return functions so we can test to see whether
the stateid was unhashed before we put the reference.
Reported-by: Andrew W Elble <aweits@rit.edu>
Tested-by: Andrew W Elble <aweits@rit.edu>
Reported-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We can potentially have several nfs4_laundromat jobs running if there
are multiple namespaces running nfsd on the box. Those are effectively
separated from one another though, so I don't see any reason to
serialize them.
Also, create_singlethread_workqueue automatically adds the
WQ_MEM_RECLAIM flag. Since we run this job on a timer, it's not really
involved in any reclaim paths. I see no need for a rescuer thread.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.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>
Commit 294ac32e99 "nfsd: protect clid and verifier generation with
client_lock" moved gen_confirm() to gen_clid().
After that commit, setclientid will return a bad reply with all-zero
verifier after copy_clid().
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If using clientid_counter, it seems possible that gen_confirm could
generate the same verifier for the same client in some situations.
Add a new counter for client confirm verifier to make sure gen_confirm
generates a different verifier on each call for the same clientid.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
v2, new helper nfs4_free_stateowner for freeing so_owner.data and sop
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Layout is a state resource, nfsd should check it too.
v2, drop unneeded updating in nfsd4_renew()
v3, fix compile error without CONFIG_NFSD_PNFS
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently, preprocess_stateid_op calls nfs4_check_olstateid which
verifies that the open stateid corresponds to the current filehandle in the
call by calling nfs4_check_fh.
If the stateid is a NFS4_DELEG_STID however, then no such check is done.
This could cause incorrect enforcement of permissions, because the
nfsd_permission() call in nfs4_check_file uses current the current
filehandle, but any subsequent IO operation will use the file descriptor
in the stateid.
Move the call to nfs4_check_fh into nfs4_check_file instead so that it
can be done for all stateid types.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
[bfields: moved fh check to avoid NULL deref in special stateid case]
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>
Split out two self contained helpers to make the function more readable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
gcc-5.0 warns about a potential uninitialized variable use in nfsd:
fs/nfsd/nfs4state.c: In function 'nfsd4_process_open2':
fs/nfsd/nfs4state.c:3781:3: warning: 'old_deny_bmap' may be used uninitialized in this function [-Wmaybe-uninitialized]
reset_union_bmap_deny(old_deny_bmap, stp);
^
fs/nfsd/nfs4state.c:3760:16: note: 'old_deny_bmap' was declared here
unsigned char old_deny_bmap;
^
This is a false positive, the code path that is warned about cannot
actually be reached.
This adds an initialization for the variable to make the warning go
away.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Checking the rpc_client pointer is not a reliable way to detect
backchannel changes: cl_cb_client is changed only after shutting down
the rpc client, so the condition cl_cb_client = tk_client will always be
true.
Check the RPC_TASK_KILLED flag instead, and rewrite the code to avoid
the buggy cl_callbacks list and fix the lifetime rules due to double
calls of the ->prepare callback operations method for this retry case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
For the sake of forgetful clients, the server should return the layouts
to the file system on 'last close' of a file (assuming that there are no
delegations outstanding to that particular client) or on delegreturn
(assuming that there are no opens on a file from that particular
client).
In theory the information is all there in current data structures, but
it's not efficiently available; nfs4_file->fi_ref includes references on
the file across all clients, but we need a per-(client, file) count.
Walking through lots of stateid's to calculate this on each close or
delegreturn would be painful.
This patch introduces infrastructure to maintain per-client opens and
delegation counters on a per-file basis.
[hch: ported to the mainline pNFS support, merged various fixes from Jeff]
Signed-off-by: Sachin Bhamare <sachin.bhamare@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If we find a non-confirmed openowner we jump to exit the function, but do
not set an error value. Fix this by factoring out a helper to do the
check and properly set the error from nfsd4_validate_stateid.
Cc: stable@vger.kernel.org
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
Pull nfsd updates from Bruce Fields:
"A quiet cycle this time; this is basically entirely bugfixes.
The few that aren't cc'd to stable are cleanup or seemed unlikely to
affect anyone much"
* 'for-4.1' of git://linux-nfs.org/~bfields/linux:
uapi: Remove kernel internal declaration
nfsd: fix nsfd startup race triggering BUG_ON
nfsd: eliminate NFSD_DEBUG
nfsd4: fix READ permission checking
nfsd4: disallow SEEK with special stateids
nfsd4: disallow ALLOCATE with special stateids
nfsd: add NFSEXP_PNFS to the exflags array
nfsd: Remove duplicate macro define for max sec label length
nfsd: allow setting acls with unenforceable DENYs
nfsd: NFSD_FAULT_INJECTION depends on DEBUG_FS
nfsd: remove unused status arg to nfsd4_cleanup_open_state
nfsd: remove bogus setting of status in nfsd4_process_open2
NFSD: Use correct reply size calculating function
NFSD: Using path_equal() for checking two paths
Commit f895b252d4 ("sunrpc: eliminate RPC_DEBUG") introduced
use of IS_ENABLED() in a uapi header which leads to a build
failure for userspace apps trying to use <linux/nfsd/debug.h>:
linux/nfsd/debug.h:18:15: error: missing binary operator before token "("
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
^
Since this was only used to define NFSD_DEBUG if CONFIG_SUNRPC_DEBUG
is enabled, replace instances of NFSD_DEBUG with CONFIG_SUNRPC_DEBUG.
Cc: stable@vger.kernel.org
Fixes: f895b252d4 "sunrpc: eliminate RPC_DEBUG"
Signed-off-by: Mark Salter <msalter@redhat.com>
Reviewed-by: Jeff Layton <jlayton@primarydata.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>
