Oops--in 916d2d84 I moved some constants into an array for
convenience, but here I'm accidentally writing to that array.

The effect is that if you ever encounter a filesystem lacking support
for ACLs or security labels, then all queries of supported attributes
will report that attribute as unsupported from then on.

Fixes: 916d2d84 "nfsd: clean up supported attribute handling"
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>

Also check d_is_symlink() in callers instead of inode->i_op->readlink
because following patches will allow NULL ->readlink for symlinks.
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>

3c8e0316 "NFSv4: do exact check about attribute specified" fixed
some handling of unsupported-attribute errors, but it also delayed
checking for unwriteable attributes till after we decode them.  This
could lead to odd behavior in the case a client attemps to set an
attribute we don't know about followed by one we try to parse.  In that
case the parser for the known attribute will attempt to parse the
unknown attribute.  It should fail in some safe way, but the error might
at least be incorrect (probably bad_xdr instead of inval).  So, it's
better to do that check at the start.

As far as I know this doesn't cause any problems with current clients
but it might be a minor issue e.g. if we encounter a future client that
supports a new attribute that we currently don't.

Cc: Yu Zhiguo <yuzg@cn.fujitsu.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>

nfserr is big-endian, so we should convert it to host-endian before
printing it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
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>

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>

Use the result of a local read to determine when to set the eof flag.  This
allows us to return the location of the end of the file atomically at the
time of the read.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
[bfields: add some documentation]
Signed-off-by: NJ. 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: NShirley Ma <shirley.ma@oracle.com>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

A number of spots in the xdr decoding follow a pattern like

	n = be32_to_cpup(p++);
	READ_BUF(n + 4);

where n is a u32.  The only bounds checking is done in READ_BUF itself,
but since it's checking (n + 4), it won't catch cases where n is very
large, (u32)(-4) or higher.  I'm not sure exactly what the consequences
are, but we've seen crashes soon after.

Instead, just break these up into two READ_BUF()s.

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

We need information about exports when crossing mountpoints during
lookup or NFSv4 readdir.  If we don't already have that information
cached, we may have to ask (and wait for) rpc.mountd.

In both cases we currently hold the i_mutex on the parent of the
directory we're asking rpc.mountd about.  We've seen situations where
rpc.mountd performs some operation on that directory that tries to take
the i_mutex again, resulting in deadlock.

With some care, we may be able to avoid that in rpc.mountd.  But it
seems better just to avoid holding a mutex while waiting on userspace.

It appears that lookup_one_len is pretty much the only operation that
needs the i_mutex.  So we could just drop the i_mutex elsewhere and do
something like

	mutex_lock()
	lookup_one_len()
	mutex_unlock()

In many cases though the lookup would have been cached and not required
the i_mutex, so it's more efficient to create a lookup_one_len() variant
that only takes the i_mutex when necessary.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
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>

Security label can be set in OPEN/CREATE request, nfsd should set
the bitmask in word2 if setting success.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The encode order should be as the bitmask defined order.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Currently we'll respond correctly to a request for either
FS_LAYOUT_TYPES or LAYOUT_TYPES, but not to a request for both
attributes simultaneously.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

After commit ae7095a7 (nfsd4: helper function for getting mounted_on
ino) we ignore the return value from get_parent_attributes().

Also, the following FATTR4_WORD2_LAYOUT_BLKSIZE uses stat.blksize, so to
avoid overwriting that, use an independent value for the parent's
attributes.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

On an absent filesystem (one served by another server), we need to be
able to handle requests for certain attributest (like fs_locations, so
the client can find out which server does have the filesystem), but
others we can't.

We forgot to take that into account when adding another attribute
bitmask work for the SECURITY_LABEL attribute.

There an export entry with the "refer" option can result in:

[   88.414272] kernel BUG at fs/nfsd/nfs4xdr.c:2249!
[   88.414828] invalid opcode: 0000 [#1] SMP
[   88.415368] Modules linked in: rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache nfsd xfs libcrc32c iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi iosf_mbi ppdev btrfs coretemp crct10dif_pclmul crc32_pclmul crc32c_intel xor ghash_clmulni_intel raid6_pq vmw_balloon parport_pc parport i2c_piix4 shpchp vmw_vmci acpi_cpufreq auth_rpcgss nfs_acl lockd grace sunrpc vmwgfx drm_kms_helper ttm drm mptspi mptscsih serio_raw mptbase e1000 scsi_transport_spi ata_generic pata_acpi [last unloaded: nfsd]
[   88.417827] CPU: 0 PID: 2116 Comm: nfsd Not tainted 4.0.7-300.fc22.x86_64 #1
[   88.418448] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/20/2014
[   88.419093] task: ffff880079146d50 ti: ffff8800785d8000 task.ti: ffff8800785d8000
[   88.419729] RIP: 0010:[<ffffffffa04b3c10>]  [<ffffffffa04b3c10>] nfsd4_encode_fattr+0x820/0x1f00 [nfsd]
[   88.420376] RSP: 0000:ffff8800785db998  EFLAGS: 00010206
[   88.421027] RAX: 0000000000000001 RBX: 000000000018091a RCX: ffff88006668b980
[   88.421676] RDX: 00000000fffef7fc RSI: 0000000000000000 RDI: ffff880078d05000
[   88.422315] RBP: ffff8800785dbb58 R08: ffff880078d043f8 R09: ffff880078d4a000
[   88.422968] R10: 0000000000010000 R11: 0000000000000002 R12: 0000000000b0a23a
[   88.423612] R13: ffff880078d05000 R14: ffff880078683100 R15: ffff88006668b980
[   88.424295] FS:  0000000000000000(0000) GS:ffff88007c600000(0000) knlGS:0000000000000000
[   88.424944] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   88.425597] CR2: 00007f40bc370f90 CR3: 0000000035af5000 CR4: 00000000001407f0
[   88.426285] Stack:
[   88.426921]  ffff8800785dbaa8 ffffffffa049e4af ffff8800785dba08 ffffffff813298f0
[   88.427585]  ffff880078683300 ffff8800769b0de8 0000089d00000001 0000000087f805e0
[   88.428228]  ffff880000000000 ffff880079434a00 0000000000000000 ffff88006668b980
[   88.428877] Call Trace:
[   88.429527]  [<ffffffffa049e4af>] ? exp_get_by_name+0x7f/0xb0 [nfsd]
[   88.430168]  [<ffffffff813298f0>] ? inode_doinit_with_dentry+0x210/0x6a0
[   88.430807]  [<ffffffff8123833e>] ? d_lookup+0x2e/0x60
[   88.431449]  [<ffffffff81236133>] ? dput+0x33/0x230
[   88.432097]  [<ffffffff8123f214>] ? mntput+0x24/0x40
[   88.432719]  [<ffffffff812272b2>] ? path_put+0x22/0x30
[   88.433340]  [<ffffffffa049ac87>] ? nfsd_cross_mnt+0xb7/0x1c0 [nfsd]
[   88.433954]  [<ffffffffa04b54e0>] nfsd4_encode_dirent+0x1b0/0x3d0 [nfsd]
[   88.434601]  [<ffffffffa04b5330>] ? nfsd4_encode_getattr+0x40/0x40 [nfsd]
[   88.435172]  [<ffffffffa049c991>] nfsd_readdir+0x1c1/0x2a0 [nfsd]
[   88.435710]  [<ffffffffa049a530>] ? nfsd_direct_splice_actor+0x20/0x20 [nfsd]
[   88.436447]  [<ffffffffa04abf30>] nfsd4_encode_readdir+0x120/0x220 [nfsd]
[   88.437011]  [<ffffffffa04b58cd>] nfsd4_encode_operation+0x7d/0x190 [nfsd]
[   88.437566]  [<ffffffffa04aa6dd>] nfsd4_proc_compound+0x24d/0x6f0 [nfsd]
[   88.438157]  [<ffffffffa0496103>] nfsd_dispatch+0xc3/0x220 [nfsd]
[   88.438680]  [<ffffffffa006f0cb>] svc_process_common+0x43b/0x690 [sunrpc]
[   88.439192]  [<ffffffffa0070493>] svc_process+0x103/0x1b0 [sunrpc]
[   88.439694]  [<ffffffffa0495a57>] nfsd+0x117/0x190 [nfsd]
[   88.440194]  [<ffffffffa0495940>] ? nfsd_destroy+0x90/0x90 [nfsd]
[   88.440697]  [<ffffffff810bb728>] kthread+0xd8/0xf0
[   88.441260]  [<ffffffff810bb650>] ? kthread_worker_fn+0x180/0x180
[   88.441762]  [<ffffffff81789e58>] ret_from_fork+0x58/0x90
[   88.442322]  [<ffffffff810bb650>] ? kthread_worker_fn+0x180/0x180
[   88.442879] Code: 0f 84 93 05 00 00 83 f8 ea c7 85 a0 fe ff ff 00 00 27 30 0f 84 ba fe ff ff 85 c0 0f 85 a5 fe ff ff e9 e3 f9 ff ff 0f 1f 44 00 00 <0f> 0b 66 0f 1f 44 00 00 be 04 00 00 00 4c 89 ef 4c 89 8d 68 fe
[   88.444052] RIP  [<ffffffffa04b3c10>] nfsd4_encode_fattr+0x820/0x1f00 [nfsd]
[   88.444658]  RSP <ffff8800785db998>
[   88.445232] ---[ end trace 6cb9d0487d94a29f ]---
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

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

Refactor the raparam hash helpers to just deal with the raparms,
and keep opening/closing files separate from that.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Whether or not a file system supports acls can be determined with
IS_POSIXACL(inode) and does not require trying to fetch any acls; the code for
computing the supported_attrs and aclsupport attributes can be simplified.
Signed-off-by: NAndreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

In the case we already have a struct file (derived from a stateid), we
still need to do permission-checking; otherwise an unauthorized user
could gain access to a file by sniffing or guessing somebody else's
stateid.

Cc: stable@vger.kernel.org
Fixes: dc97618d "nfsd4: separate splice and readv cases"
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

NFS4_MAXLABELLEN has defined for sec label max length, use it directly.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
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>

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

Return status after nfsd4_decode_stateid failed.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

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: NChristoph Hellwig <hch@lst.de>

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

RFC 3530 14.2.24 says

	This value represents the length of the names of the directory
	entries and the cookie value for these entries.  This length
	represents the XDR encoding of the data (names and cookies)...

The "xdr encoding" of the name should probably include the 4 bytes for
the length.

But this is all just a hint so not worth e.g. backporting to stable.

Also reshuffle some lines to more clearly group together the
dircount-related code.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Fix a bug where nfsd4_encode_components_esc() incorrectly calculates the
length of server array in fs_location4--note that it is a count of the
number of array elements, not a length in bytes.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Fixes: 082d4bd7 (nfsd4: "backfill" using write_bytes_to_xdr_buf)
Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Fix a bug where nfsd4_encode_components_esc() includes the esc_end char as
an additional string encoding.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Cc: stable@vger.kernel.org
Fixes: e7a0444a "nfsd: add IPv6 addr escaping to fs_location hosts"
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NJeff Layton <jlayton@primarydata.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

DEALLOCATE only returns a status value, meaning we can use the noop()
xdr encoder to reply to the client.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NJ. 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: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The calculation of page_ptr here is wrong in the case the read doesn't
start at an offset that is a multiple of a page.

The result is that nfs4svc_encode_compoundres sets rq_next_page to a
value one too small, and then the loop in svc_free_res_pages may
incorrectly fail to clear a page pointer in rq_respages[].

Pages left in rq_respages[] are available for the next rpc request to
use, so xdr data may be written to that page, which may hold data still
waiting to be transmitted to the client or data in the page cache.

The observed result was silent data corruption seen on an NFSv4 client.

We tag this as "fixing" 05638dc7 because that commit exposed this
bug, though the incorrect calculation predates it.

Particular thanks to Andrea Arcangeli and David Gilbert for analysis and
testing.

Fixes: 05638dc7 "nfsd4: simplify server xdr->next_page use"
Cc: stable@vger.kernel.org
Reported-by: NAndrea Arcangeli <aarcange@redhat.com>
Tested-by: N"Dr. David Alan Gilbert" <dgilbert@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>