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: NChristoph 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: NChristoph 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: NChristoph 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: NChristoph 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: NChristoph 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: NChristoph Hellwig <hch@lst.de>
Acked-by: NTrond 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: NChristoph 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: NChristoph Hellwig <hch@lst.de>

Signed-off-by: NChristoph Hellwig <hch@lst.de>

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: NScott Mayhew <smayhew@redhat.com>
Cc: stable@kernel.vger.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

  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: NJani Tuovila <tuovila@synopsys.com>
Signed-off-by: NAri Kauppi <ari@synopsys.com>
[colin.king@canonical.com: use LAYOUT_TYPE_MAX instead of 32]
Cc: stable@vger.kernel.org
Reviewed-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. 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: 2282cd2c "NFSD: Get response size before operation..."
Signed-off-by: NJ. 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: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. 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: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. 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: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. 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: NJ. Bruce Fields <bfields@redhat.com>

After fae5096a "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: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. 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: NAndreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: NJ. 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: NJ. 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: NAnna Schumaker <bjschuma@netapp.com>
Signed-off-by: NJ. 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: NJ. 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: NOleg Drokin <green@linuxhacker.ru>
Signed-off-by: NJ. 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: NJeff Layton <jlayton@poochiereds.net>
Reviewed-by: NWeston Andros Adamson <dros@primarydata.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NTom Haynes <loghyr@primarydata.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJeff Layton <jlayton@poochiereds.net>
Signed-off-by: NJ. 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: NAndrew Elble <aweits@rit.edu>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. 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: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. 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: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NJ. 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: NAl 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: NChristoph Hellwig <hch@lst.de>
Acked-by: NJ. Bruce Fields <bfields@fieldses.org>
Signed-off-by: NAl 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: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NJ. Bruce Fields <bfields@fieldses.org>
Signed-off-by: NAl 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: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NJ. 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: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. 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: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. 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: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. 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: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. 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: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

If the client uses a special stateid then we'll pass a NULL file to
vfs_llseek.

Fixes: 24bab491 " NFSD: Implement SEEK"
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: stable@vger.kernel.org
Reported-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NJ. 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: 95d871f0 "nfsd: Add ALLOCATE support"
Cc: stable@vger.kernel.org
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>