s_stid->si_generation is a u32, copy->stateid.seqid is a __be32, so we
should be byte-swapping here if necessary.
This effectively undoes the byte-swap performed when reading
s_stid->s_generation in nfsd4_decode_copy(). Without this second swap,
the stateid we sent to the source in READ could be different from the
one the client provided us in the COPY. We didn't spot this in testing
since our implementation always uses a 0 in the seqid field. But other
implementations might not do that.
You'd think we should just skip the byte-swapping entirely, but the
s_stid field can be used for either our own stateids (in the
intra-server case) or foreign stateids (in the inter-server case), and
the former are interpreted by us and need byte-swapping.
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: d5e54eeb0e3d ("NFSD add nfs4 inter ssc to nfsd4_copy")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Given a universal address, mount the source server from the destination
server. Use an internal mount. Call the NFS client nfs42_ssc_open to
obtain the NFS struct file suitable for nfsd_copy_range.
Ability to do "inter" server-to-server depends on the an nfsd kernel
parameter "inter_copy_offload_enable".
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
The inter server to server COPY source server filehandle
is a foreign filehandle as the COPY is sent to the destination
server.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Introducing the COPY_NOTIFY operation.
Create a new unique stateid that will keep track of the copy
state and the upcoming READs that will use that stateid.
Each associated parent stateid has a list of copy
notify stateids. A copy notify structure makes a copy of
the parent stateid and a clientid and will use it to look
up the parent stateid during the READ request (suggested
by Trond Myklebust <trond.myklebust@hammerspace.com>).
At nfs4_put_stid() time, we walk the list of the associated
copy notify stateids and delete them.
Laundromat thread will traverse globally stored copy notify
stateid in idr and notice if any haven't been referenced in the
lease period, if so, it'll remove them.
Return single netaddr to advertise to the copy.
Suggested-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
Static checker revealed possible error path leading to possible
NULL pointer dereferencing.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: e0639dc5805a: ("NFSD introduce async copy feature")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The NFSv4.2 CLONE operation has implicit persistence requirements on the
target file, since there is no protocol requirement that the client issue
a separate operation to persist data.
For that reason, we should call vfs_fsync_range() on the destination file
after a successful call to vfs_clone_file_range().
Fixes: ffa0160a10 ("nfsd: implement the NFSv4.2 CLONE operation")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.5+
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add support to allow the server to reset the boot verifier in order to
force clients to resend I/O after a timeout failure.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Have nfs4_preprocess_stateid_op pass back a nfsd_file instead of a filp.
Since we now presume that the struct file will be persistent in most
cases, we can stop fiddling with the raparms in the read code. This
also means that we don't really care about the rd_tmp_file field
anymore.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Scott Mayhew revived an old api that communicates with a userspace
daemon to manage some on-disk state that's used to track clients across
server reboots. We've been using a usermode_helper upcall for that, but
it's tough to run those with the right namespaces, so a daemon is much
friendlier to container use cases.
Trond fixed nfsd's handling of user credentials in user namespaces. He
also contributed patches that allow containers to support different sets
of NFS protocol versions.
The only remaining container bug I'm aware of is that the NFS reply
cache is shared between all containers. If anyone's aware of other gaps
in our container support, let me know.
The rest of this is miscellaneous bugfixes.
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Merge tag 'nfsd-5.2' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"This consists mostly of nfsd container work:
Scott Mayhew revived an old api that communicates with a userspace
daemon to manage some on-disk state that's used to track clients
across server reboots. We've been using a usermode_helper upcall for
that, but it's tough to run those with the right namespaces, so a
daemon is much friendlier to container use cases.
Trond fixed nfsd's handling of user credentials in user namespaces. He
also contributed patches that allow containers to support different
sets of NFS protocol versions.
The only remaining container bug I'm aware of is that the NFS reply
cache is shared between all containers. If anyone's aware of other
gaps in our container support, let me know.
The rest of this is miscellaneous bugfixes"
* tag 'nfsd-5.2' of git://linux-nfs.org/~bfields/linux: (23 commits)
nfsd: update callback done processing
locks: move checks from locks_free_lock() to locks_release_private()
nfsd: fh_drop_write in nfsd_unlink
nfsd: allow fh_want_write to be called twice
nfsd: knfsd must use the container user namespace
SUNRPC: rsi_parse() should use the current user namespace
SUNRPC: Fix the server AUTH_UNIX userspace mappings
lockd: Pass the user cred from knfsd when starting the lockd server
SUNRPC: Temporary sockets should inherit the cred from their parent
SUNRPC: Cache the process user cred in the RPC server listener
nfsd: Allow containers to set supported nfs versions
nfsd: Add custom rpcbind callbacks for knfsd
SUNRPC: Allow further customisation of RPC program registration
SUNRPC: Clean up generic dispatcher code
SUNRPC: Add a callback to initialise server requests
SUNRPC/nfs: Fix return value for nfs4_callback_compound()
nfsd: handle legacy client tracking records sent by nfsdcld
nfsd: re-order client tracking method selection
nfsd: keep a tally of RECLAIM_COMPLETE operations when using nfsdcld
nfsd: un-deprecate nfsdcld
...
Support use of the --nfs-version/--no-nfs-version arguments to rpc.nfsd
in containers.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
This patch fixes the following warnings:
fs/affs/affs.h:124:38: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/configfs/dir.c:1692:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/configfs/dir.c:1694:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ceph/file.c:249:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/hash.c:233:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/hash.c:246:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext2/inode.c:1237:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext2/inode.c:1244:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1182:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1188:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1432:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ext4/indirect.c:1440:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/f2fs/node.c:618:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/f2fs/node.c:620:8: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/btrfs/ref-verify.c:522:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/gfs2/bmap.c:711:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/gfs2/bmap.c:722:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/jffs2/fs.c:339:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/nfsd/nfs4proc.c:429:12: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ufs/util.h:62:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/ufs/util.h:43:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/fcntl.c:770:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/seq_file.c:319:10: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/libfs.c:148:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/libfs.c:150:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/signalfd.c:178:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
fs/locks.c:1473:16: warning: this statement may fall through [-Wimplicit-fallthrough=]
Warning level 3 was used: -Wimplicit-fallthrough=3
This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
The idea here was that renaming a file on a nosubtreecheck export would
make lookups of the old filehandle return STALE, making it impossible
for clients to reclaim opens.
But during the grace period I think we should also hold off on
operations that would break delegations.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Zero-length writes are legal; from 5661 section 18.32.3: "If the count
is zero, the WRITE will succeed and return a count of zero subject to
permissions checking".
This check is unnecessary and is causing zero-length reads to return
EINVAL.
Cc: stable@vger.kernel.org
Fixes: 3fd9557aec "NFSD: Refactor the generic write vector fill helper"
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Make sure we have a saved filehandle, otherwise we'll oops with a null
pointer dereference in nfs4_preprocess_stateid_op().
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Upon receiving a request for async copy, create a new kthread. If we
get asynchronous request, make sure to copy the needed arguments/state
from the stack before starting the copy. Then start the thread and reply
back to the client indicating copy is asynchronous.
nfsd_copy_file_range() will copy in a loop over the total number of
bytes is needed to copy. In case a failure happens in the middle, we
ignore the error and return how much we copied so far. Once done
creating a workitem for the callback workqueue and send CB_OFFLOAD with
the results.
The lifetime of the copy stateid is bound to the vfs copy. This way we
don't need to keep the nfsd_net structure for the callback. We could
keep it around longer so that an OFFLOAD_STATUS that came late would
still get results, but clients should be able to deal without that.
We handle OFFLOAD_CANCEL by sending a signal to the copy thread and
calling kthread_stop.
A client should cancel any ongoing copies before calling DESTROY_CLIENT;
if not, we return a CLIENT_BUSY error.
If the client is destroyed for some other reason (lease expiration, or
server shutdown), we must clean up any ongoing copies ourselves.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
[colin.king@canonical.com: fix leak in error case]
[bfields@fieldses.org: remove signalling, merge patches]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
fill_in_write_vector() is nearly the same logic as
svc_fill_write_vector(), but there are a few differences so that
the former can handle multiple WRITE payloads in a single COMPOUND.
svc_fill_write_vector() can be adjusted so that it can be used in
the NFSv4 WRITE code path too. Instead of assuming the pages are
coming from rq_args.pages, have the caller pass in the page list.
The immediate benefit is a reduction of code duplication. It also
prevents the NFSv4 WRITE decoder from passing an empty vector
element when the transport has provided the payload in the xdr_buf's
page array.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We're encoding a single op in the reply but leaving the number of ops
zero, so the reply makes no sense.
Somewhat academic as this isn't a case any real client will hit, though
in theory perhaps that could change in a future protocol extension.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Document a couple things that confused me on a recent reading.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If the client is only renewing state a little sooner than once a lease
period, then it might not discover the server has restarted till close
to the end of the grace period, and might run out of time to do the
actual reclaim.
Extend the grace period by a second each time we notice there are
clients still trying to reclaim, up to a limit of another whole lease
period.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We're neglecting to clear the umask after it's set, which can cause a
later unrelated rpc to (incorrectly) use the same umask if it happens to
be processed by the same thread.
There's a more subtle problem here too:
An NFSv4 compound request is decoded all in one pass before any
operations are executed.
Currently we're setting current->fs->umask at the time we decode the
compound. In theory a single compound could contain multiple creates
each setting a umask. In that case we'd end up using whichever umask
was passed in the *last* operation as the umask for all the creates,
whether that was correct or not.
So, we should just be saving the umask at decode time and waiting to set
it until we actually process the corresponding operation.
In practice it's unlikely any client would do multiple creates in a
single compound. And even if it did they'd likely be from the same
process (hence carry the same umask). So this is a little academic, but
we should get it right anyway.
Fixes: 47057abde5 (nfsd: add support for the umask attribute)
Cc: stable@vger.kernel.org
Reported-by: Lucash Stach <l.stach@pengutronix.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This helps record the identity and timing of the ops in each NFSv4
COMPOUND, replacing dprintk calls that did much the same thing.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NFSv4 read compound processing invokes nfsd_splice_read and
nfs_readv directly, so the trace points currently in nfsd_read are
not invoked for NFSv4 reads.
Move the NFSD READ trace points to common helpers so that NFSv4
reads are captured.
Also, record any local I/O error that occurs, the total count of
bytes that were actually returned, and whether splice or vectored
read was used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NFSv4 write compound processing invokes nfsd_vfs_write directly. The
trace points currently in nfsd_write are not effective for NFSv4
writes.
Move the trace points into the shared nfsd_vfs_write() helper.
After the I/O, we also want to record any local I/O error that
might have occurred, and the total count of bytes that were actually
moved (rather than the requested number).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Follow naming convention used in client and in sunrpc layers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
A client that sends more than a hundred ops in a single compound
currently gets an rpc-level GARBAGE_ARGS error.
It would be more helpful to return NFS4ERR_RESOURCE, since that gives
the client a better idea how to recover (for example by splitting up the
compound into smaller compounds).
This is all a bit academic since we've never actually seen a reason for
clients to send such long compounds, but we may as well fix it.
While we're there, just use NFSD4_MAX_OPS_PER_COMPOUND == 16, the
constant we already use in the 4.1 case, instead of hard-coding 100.
Chances anyone actually uses even 16 ops per compound are small enough
that I think there's a neglible risk or any regression.
This fixes pynfs test COMP6.
Reported-by: "Lu, Xinyu" <luxy.fnst@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clients must be able to read a file in order to execute it, and for pNFS
that means the client needs to be able to perform a LAYOUTGET on the file.
This behavior for executable-only files was added for OPEN in commit
a043226bc1 "nfsd4: permit read opens of executable-only files".
This fixes up xfstests generic/126 on block/scsi layouts.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
- fix a number of races in the NFSv4+ state code.
- fix some shutdown crashes in multiple-network-namespace cases.
- relax our 4.1 session limits; if you've an artificially low limit
to the number of 4.1 clients that can mount simultaneously, try
upgrading.
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Merge tag 'nfsd-4.15' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Lots of good bugfixes, including:
- fix a number of races in the NFSv4+ state code
- fix some shutdown crashes in multiple-network-namespace cases
- relax our 4.1 session limits; if you've an artificially low limit
to the number of 4.1 clients that can mount simultaneously, try
upgrading"
* tag 'nfsd-4.15' of git://linux-nfs.org/~bfields/linux: (22 commits)
SUNRPC: Improve ordering of transport processing
nfsd: deal with revoked delegations appropriately
svcrdma: Enqueue after setting XPT_CLOSE in completion handlers
nfsd: use nfs->ns.inum as net ID
rpc: remove some BUG()s
svcrdma: Preserve CB send buffer across retransmits
nfds: avoid gettimeofday for nfssvc_boot time
fs, nfsd: convert nfs4_file.fi_ref from atomic_t to refcount_t
fs, nfsd: convert nfs4_cntl_odstate.co_odcount from atomic_t to refcount_t
fs, nfsd: convert nfs4_stid.sc_count from atomic_t to refcount_t
lockd: double unregister of inetaddr notifiers
nfsd4: catch some false session retries
nfsd4: fix cached replies to solo SEQUENCE compounds
sunrcp: make function _svc_create_xprt static
SUNRPC: Fix tracepoint storage issues with svc_recv and svc_rqst_status
nfsd: use ARRAY_SIZE
nfsd: give out fewer session slots as limit approaches
nfsd: increase DRC cache limit
nfsd: remove unnecessary nofilehandle checks
nfs_common: convert int to bool
...
do_gettimeofday() is deprecated and we should generally use time64_t
based functions instead.
In case of nfsd, all three users of nfssvc_boot only use the initial
time as a unique token, and are not affected by it overflowing, so they
are not affected by the y2038 overflow.
This converts the structure to timespec64 anyway and adds comments
to all uses, to document that we have thought about it and avoid
having to look at it again.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Commit 34b1744c91 ("nfsd4: define ->op_release for compound ops")
defined a couple ->op_release functions and run them if necessary.
But there's a problem with that is that it reused
nfsd4_secinfo_release() as the op_release of OP_SECINFO_NO_NAME, and
caused a leak on struct nfsd4_secinfo_no_name in
nfsd4_encode_secinfo_no_name(), because there's no .si_exp field in
struct nfsd4_secinfo_no_name.
I found this because I was unable to umount an ext4 partition after
exporting it via NFS & run fsstress on the nfs mount. A simplified
reproducer would be:
# mount a local-fs device at /mnt/test, and export it via NFS with
# fsid=0 export option (this is required)
mount /dev/sda5 /mnt/test
echo "/mnt/test *(rw,no_root_squash,fsid=0)" >> /etc/exports
service nfs restart
# locally mount the nfs export with all default, note that I have
# nfsv4.1 configured as the default nfs version, because of the
# fsid export option, v4 mount would fail and fall back to v3
mount localhost:/mnt/test /mnt/nfs
# try to umount the underlying device, but got EBUSY
umount /mnt/nfs
service nfs stop
umount /mnt/test <=== EBUSY here
Fixed it by defining a separate nfsd4_secinfo_no_name_release()
function as the op_release method of OP_SECINFO_NO_NAME that
releases the correct nfsd4_secinfo_no_name structure.
Fixes: 34b1744c91 ("nfsd4: define ->op_release for compound ops")
Signed-off-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
These checks should have already be done centrally in
nfsd4_proc_compound, the checks in each individual operation are
unnecessary.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Most encoders do nothing in the error case. But they can still screw
things up in that case: most errors happen very early in rpc processing,
possibly before argument fields are filled in and bounds-tested, so
encoders that do anything other than immediately bail on error can
easily crash in odd error cases.
So just handle errors centrally most of the time to remove the chance of
error.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Run a separate ->op_release function if necessary instead of depending
on the xdr encoder to do this.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Merge tag 'v4.12-rc5' into nfsd tree
Update to get f0c3192cee "virtio_net: lower limit on buffer size".
That bug was interfering with my nfsd testing.
if we receive a compound such that:
- the sessionid, slot, and sequence number in the SEQUENCE op
match a cached succesful reply with N ops, and
- the Nth operation of the compound is a PUTFH, PUTPUBFH,
PUTROOTFH, or RESTOREFH,
then nfsd4_sequence will return 0 and set cstate->status to
nfserr_replay_cache. The current filehandle will not be set. This will
cause us to call check_nfsd_access with first argument NULL.
To nfsd4_compound it looks like we just succesfully executed an
operation that set a filehandle, but the current filehandle is not set.
Fix this by moving the nfserr_replay_cache earlier. There was never any
reason to have it after the encode_op label, since the only case where
he hit that is when opdesc->op_func sets it.
Note that there are two ways we could hit this case:
- a client is resending a previously sent compound that ended
with one of the four PUTFH-like operations, or
- a client is sending a *new* compound that (incorrectly) shares
sessionid, slot, and sequence number with a previously sent
compound, and the length of the previously sent compound
happens to match the position of a PUTFH-like operation in the
new compound.
The second is obviously incorrect client behavior. The first is also
very strange--the only purpose of a PUTFH-like operation is to set the
current filehandle to be used by the following operation, so there's no
point in having it as the last in a compound.
So it's likely this requires a buggy or malicious client to reproduce.
Reported-by: Scott Mayhew <smayhew@redhat.com>
Cc: stable@kernel.vger.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd4_ops contains function pointers, and marking it as constant avoids
it being able to be used as an attach vector for code injections.
Signed-off-by: Christoph Hellwig <hch@lst.de>
struct svc_procinfo contains function pointers, and marking it as
constant avoids it being able to be used as an attach vector for
code injections.
Signed-off-by: Christoph Hellwig <hch@lst.de>
pc_count is the only writeable memeber of struct svc_procinfo, which is
a good candidate to be const-ified as it contains function pointers.
This patch moves it into out out struct svc_procinfo, and into a
separate writable array that is pointed to by struct svc_version.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pass union nfsd4_op_u to the op_func callbacks instead of using unsafe
function pointer casts.
It also adds two missing structures to struct nfsd4_op.u to facilitate
this.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Except for a lot of unnecessary casts this typedef only has one user,
so remove the casts and expand it in struct nfsd4_operation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pass union nfsd4_op_u to the op_set_currentstateid callbacks instead of
using unsafe function pointer casts.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Given the args union in struct nfsd4_op a name, and pass it to the
op_set_currentstateid callbacks instead of using unsafe function
pointer casts.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Drop the resp argument as it can trivially be derived from the rqstp
argument. With that all functions now have the same prototype, and we
can remove the unsafe casting to kxdrproc_t.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
Drop the argp argument as it can trivially be derived from the rqstp
argument. With that all functions now have the same prototype, and we
can remove the unsafe casting to kxdrproc_t.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Drop the argp and resp arguments as they can trivially be derived from
the rqstp argument. With that all functions now have the same prototype,
and we can remove the unsafe casting to svc_procfunc as well as the
svc_procfunc typedef itself.
Signed-off-by: Christoph Hellwig <hch@lst.de>
UBSAN: Undefined behaviour in fs/nfsd/nfs4proc.c:1262:34
shift exponent 128 is too large for 32-bit type 'int'
Depending on compiler+architecture, this may cause the check for
layout_type to succeed for overly large values (which seems to be the
case with amd64). The large value will be later used in de-referencing
nfsd4_layout_ops for function pointers.
Reported-by: Jani Tuovila <tuovila@synopsys.com>
Signed-off-by: Ari Kauppi <ari@synopsys.com>
[colin.king@canonical.com: use LAYOUT_TYPE_MAX instead of 32]
Cc: stable@vger.kernel.org
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
I'm hitting the BUG in nfsd4_max_reply() at fs/nfsd/nfs4proc.c:2495 when
client sends an operation the server doesn't support.
in nfsd4_max_reply() it checks for NULL rsize_bop but a non-supported
operation wouldn't have that set.
Cc: Kinglong Mee <kinglongmee@gmail.com>
Fixes: 2282cd2c05 "NFSD: Get response size before operation..."
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NFSv4 requires a transport "that is specified to avoid network
congestion" (RFC 7530, section 3.1, paragraph 2). In practical terms,
that means that you should not run NFSv4 over UDP. The server has never
enforced that requirement, however.
This patchset fixes this by adding a new flag to the svc_version that
states that it has these transport requirements. With that, we can check
that the transport has XPT_CONG_CTRL set before processing an RPC. If it
doesn't we reject it with RPC_PROG_MISMATCH.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It's just simpler to read this way, IMO. Also, no need to explicitly
set vs_hidden to false in the nfsacl ones.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NFSD usess PAGE_SIZE as the reply size estimate for RPCs which don't
support op_rsize_bop(), A PAGE_SIZE (4096) is larger than many real
response sizes, eg, access (op_encode_hdr_size + 2), seek
(op_encode_hdr_size + 3).
This patch just adds op_rsize_bop() for all RPCs getting response size.
An overestimate is generally safe but the tighter estimates are probably
better.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently turning on NFSv4.2 results in 4.2 clients suddenly seeing the
individual file labels as they're set on the server. This is not what
they've previously seen, and not appropriate in may cases. (In
particular, if clients have heterogenous security policies then one
client's labels may not even make sense to another.) Labeled NFS should
be opted in only in those cases when the administrator knows it makes
sense.
It's helpful to be able to turn 4.2 on by default, and otherwise the
protocol upgrade seems free of regressions. So, default labeled NFS to
off and provide an export flag to reenable it.
Users wanting labeled NFS support on an export will henceforth need to:
- make sure 4.2 support is enabled on client and server (as
before), and
- upgrade the server nfs-utils to a version supporting the new
"security_label" export flag.
- set that "security_label" flag on the export.
This is commit may be seen as a regression to anyone currently depending
on security labels. We believe those cases are currently rare.
Reported-by: tibbs@math.uh.edu
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
After fae5096ad2 "nfsd: assume writeable exportabled filesystems have
f_sync" we no longer modify this argument.
This is just cleanup, no change in functionality.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clients can set the umask attribute when creating files to cause the
server to apply it always except when inheriting permissions from the
parent directory. That way, the new files will end up with the same
permissions as files created locally.
See https://tools.ietf.org/html/draft-ietf-nfsv4-umask-02 for more
details.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Minor cleanup, no change in behavior.
Provide helpers for some common attribute bitmap operations. Drop some
comments that just echo the code.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
I only implemented the sync version of this call, since it's the
easiest. I can simply call vfs_copy_range() and have the vfs do the
right thing for the filesystem being exported.
Signed-off-by: Anna Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We need an fh_verify to make sure we at least have a dentry, but actual
permission checks happen later.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When doing a create (mkdir/mknod) on a name, it's worth
checking the name exists first before returning EACCES in case
the directory is not writeable by the user.
This makes return values on the client more consistent
regardless of whenever the entry there is cached in the local
cache or not.
Another positive side effect is certain programs only expect
EEXIST in that case even despite POSIX allowing any valid
error to be returned.
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If the underlying filesystem supports multiple layout types, then there
is little reason not to advertise that fact to clients and let them
choose what type to use.
Turn the ex_layout_type field into a bitfield. For each supported
layout type, we set a bit in that field. When the client requests a
layout, ensure that the bit for that layout type is set. When the
client requests attributes, send back a list of supported types.
Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Reviewed-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Tom Haynes <loghyr@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This addresses the conundrum referenced in RFC5661 18.35.3,
and will allow clients to return state to the server using the
machine credentials.
The biggest part of the problem is that we need to allow the client
to send a compound op with integrity/privacy on mounts that don't
have it enabled.
Add server support for properly decoding and using spo_must_enforce
and spo_must_allow bits. Add support for machine credentials to be
used for CLOSE, OPEN_DOWNGRADE, LOCKU, DELEGRETURN,
and TEST/FREE STATEID.
Implement a check so as to not throw WRONGSEC errors when these
operations are used if integrity/privacy isn't turned on.
Without this, Linux clients with credentials that expired while holding
delegations were getting stuck in an endless loop.
Signed-off-by: Andrew Elble <aweits@rit.edu>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This is a simple extension to the block layout driver to use SCSI
persistent reservations for access control and fencing, as well as
SCSI VPD pages for device identification.
For this we need to pass the nfs4_client to the proc_getdeviceinfo method
to generate the reservation key, and add a new fence_client method
to allow for fence actions in the layout driver.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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>