The code to step to the next page seems reasonably self-contained.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

A freebsd NFSv4.0 client was getting rare IO errors expanding a tarball.
A network trace showed the server returning BAD_XDR on the final getattr
of a getattr+write+getattr compound.  The final getattr started on a
page boundary.

I believe the Linux client ignores errors on the post-write getattr, and
that that's why we haven't seen this before.

Cc: stable@vger.kernel.org
Reported-by: NRick Macklem <rmacklem@uoguelph.ca>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The nfs4_open_delegation logic is unecessarily baroque.

Also stop pretending we support write delegations in several places.

Some day we will support write delegations, but when that happens adding
back in these flag parameters will be the easy part.  For now they're
just confusing.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

When an exclusive create is done with the mode bits
set (aka open(testfile, O_CREAT | O_EXCL, 0777)) this
causes a OPEN op followed by a SETATTR op. When a
read delegation is given in the OPEN, it causes
the SETATTR to delay with EAGAIN until the
delegation is recalled.

This patch caused exclusive creates to give out
a write delegation (which turn into no delegation)
which allows the SETATTR seamlessly succeed.
Signed-off-by: NSteve Dickson <steved@redhat.com>
[bfields: do this for any CREATE, not just exclusive; comment]
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

In testing I notice that some of the pynfs tests forget to send any
cb_sec flavors, and that we haven't necessarily errored out in that case
before.

I'll fix pynfs, but am also inclined to default to trying AUTH_NONE in
that case in case this is something clients actually do.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We don't support gss on the backchannel.  We should state that fact up
front rather than just letting things continue and later making the
client try to figure out why the backchannel isn't working.

Trond suggested instead returning NFS4ERR_NOENT.  I think it would be
tricky for the client to distinguish between the case "I don't support
gss on the backchannel" and "I can't find that in my cache, please
create another context and try that instead", and I'd prefer something
that currently doesn't have any other meaning for this operation, hence
the (somewhat arbitrary) NFS4ERR_ENCR_ALG_UNSUPP.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Do a minimal SP4_MACH_CRED implementation suggested by Trond, ignoring
the client-provided spo_must_* arrays and just enforcing credential
checks for the minimum required operations.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Store a pointer to the gss mechanism used in the rq_cred and cl_cred.
This will make it easier to enforce SP4_MACH_CRED, which needs to
compare the mechanism used on the exchange_id with that used on
protected operations.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

In C, signed integer overflow results in undefined behavior, but unsigned
overflow wraps around. So do the subtraction first, then cast to signed.
Reported-by: NJoakim Tjernlund <joakim.tjernlund@transmode.se>
Signed-off-by: NJim Rees <rees@umich.edu>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Implement labeled NFS on the server: encoding and decoding, and writing
and reading, of file labels.

Enabled with CONFIG_NFSD_V4_SECURITY_LABEL.
Signed-off-by: NMatthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: NMiguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: NPhua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: NKhin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This enables NFSv4.2 support for the server. To enable this
code do the following:
  echo "+4.2" >/proc/fs/nfsd/versions

after the nfsd kernel module is loaded.

On its own this does nothing except allow the server to respond to
compounds with minorversion set to 2.  All the new NFSv4.2 features are
optional, so this is perfectly legal.
Signed-off-by: NSteve Dickson <steved@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This code assumes that any client using exchange_id is using NFSv4.1,
but with the introduction of 4.2 that will no longer true.

This main effect of this is that client callbacks will use the same
minorversion as that used on the exchange_id.

Note that clients are forbidden from mixing 4.1 and 4.2 compounds.  (See
rfc 5661, section 2.7, #13: "A client MUST NOT attempt to use a stateid,
filehandle, or similar returned object from the COMPOUND procedure with
minor version X for another COMPOUND procedure with minor version Y,
where X != Y.")  However, we do not currently attempt to enforce this
except in the case of mixing zero minor version with non-zero minor
versions.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The fh_lock_parent(), nfsd_truncate(), nfsd_notify_change() and
nfsd_sync_dir() fuctions are neither implemented nor used, just remove
them.
Signed-off-by: NZhao Hongjiang <zhaohongjiang@huawei.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NMatthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: NMiguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: NPhua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: NKhin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: NSteve Dickson <steved@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Toralf reported the following oops to the linux-nfs mailing list:

    -----------------[snip]------------------
    NFSD: unable to generate recoverydir name (-2).
    NFSD: disabling legacy clientid tracking. Reboot recovery will not function correctly!
    BUG: unable to handle kernel NULL pointer dereference at 000003c8
    IP: [<f90a3d91>] nfsd4_client_tracking_exit+0x11/0x50 [nfsd]
    *pdpt = 000000002ba33001 *pde = 0000000000000000
    Oops: 0000 [#1] SMP
    Modules linked in: loop nfsd auth_rpcgss ipt_MASQUERADE xt_owner xt_multiport ipt_REJECT xt_tcpudp xt_recent xt_conntrack nf_conntrack_ftp xt_limit xt_LOG iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_filter ip_tables x_tables af_packet pppoe pppox ppp_generic slhc bridge stp llc tun arc4 iwldvm mac80211 coretemp kvm_intel uvcvideo sdhci_pci sdhci mmc_core videobuf2_vmalloc videobuf2_memops usblp videobuf2_core i915 iwlwifi psmouse videodev cfg80211 kvm fbcon bitblit cfbfillrect acpi_cpufreq mperf evdev softcursor font cfbimgblt i2c_algo_bit cfbcopyarea intel_agp intel_gtt drm_kms_helper snd_hda_codec_conexant drm agpgart fb fbdev tpm_tis thinkpad_acpi tpm nvram e1000e rfkill thermal ptp wmi pps_core tpm_bios 8250_pci processor 8250 ac snd_hda_intel snd_hda_codec snd_pcm battery video i2c_i801 snd_page_alloc snd_timer button serial_core i2c_core snd soundcore thermal_sys hwmon aesni_intel ablk_helper cryp
td lrw aes_i586 xts gf128mul cbc fuse nfs lockd sunrpc dm_crypt dm_mod hid_monterey hid_microsoft hid_logitech hid_ezkey hid_cypress hid_chicony hid_cherry hid_belkin hid_apple hid_a4tech hid_generic usbhid hid sr_mod cdrom sg [last unloaded: microcode]
    Pid: 6374, comm: nfsd Not tainted 3.9.1 #6 LENOVO 4180F65/4180F65
    EIP: 0060:[<f90a3d91>] EFLAGS: 00010202 CPU: 0
    EIP is at nfsd4_client_tracking_exit+0x11/0x50 [nfsd]
    EAX: 00000000 EBX: fffffffe ECX: 00000007 EDX: 00000007
    ESI: eb9dcb00 EDI: eb2991c0 EBP: eb2bde38 ESP: eb2bde34
    DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
    CR0: 80050033 CR2: 000003c8 CR3: 2ba80000 CR4: 000407f0
    DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
    DR6: ffff0ff0 DR7: 00000400
    Process nfsd (pid: 6374, ti=eb2bc000 task=eb2711c0 task.ti=eb2bc000)
    Stack:
    fffffffe eb2bde4c f90a3e0c f90a7754 fffffffe eb0a9c00 eb2bdea0 f90a41ed
    eb2991c0 1b270000 eb2991c0 eb2bde7c f9099ce9 eb2bde98 0129a020 eb29a020
    eb2bdecc eb2991c0 eb2bdea8 f9099da5 00000000 eb9dcb00 00000001 67822f08
    Call Trace:
    [<f90a3e0c>] legacy_recdir_name_error+0x3c/0x40 [nfsd]
    [<f90a41ed>] nfsd4_create_clid_dir+0x15d/0x1c0 [nfsd]
    [<f9099ce9>] ? nfsd4_lookup_stateid+0x99/0xd0 [nfsd]
    [<f9099da5>] ? nfs4_preprocess_seqid_op+0x85/0x100 [nfsd]
    [<f90a4287>] nfsd4_client_record_create+0x37/0x50 [nfsd]
    [<f909d6ce>] nfsd4_open_confirm+0xfe/0x130 [nfsd]
    [<f90980b1>] ? nfsd4_encode_operation+0x61/0x90 [nfsd]
    [<f909d5d0>] ? nfsd4_free_stateid+0xc0/0xc0 [nfsd]
    [<f908fd0b>] nfsd4_proc_compound+0x41b/0x530 [nfsd]
    [<f9081b7b>] nfsd_dispatch+0x8b/0x1a0 [nfsd]
    [<f857b85d>] svc_process+0x3dd/0x640 [sunrpc]
    [<f908165d>] nfsd+0xad/0x110 [nfsd]
    [<f90815b0>] ? nfsd_destroy+0x70/0x70 [nfsd]
    [<c1054824>] kthread+0x94/0xa0
    [<c1486937>] ret_from_kernel_thread+0x1b/0x28
    [<c1054790>] ? flush_kthread_work+0xd0/0xd0
    Code: 86 b0 00 00 00 90 c5 0a f9 c7 04 24 70 76 0a f9 e8 74 a9 3d c8 eb ba 8d 76 00 55 89 e5 53 66 66 66 66 90 8b 15 68 c7 0a f9 85 d2 <8b> 88 c8 03 00 00 74 2c 3b 11 77 28 8b 5c 91 08 85 db 74 22 8b
    EIP: [<f90a3d91>] nfsd4_client_tracking_exit+0x11/0x50 [nfsd] SS:ESP 0068:eb2bde34
    CR2: 00000000000003c8
    ---[ end trace 09e54015d145c9c6 ]---

The problem appears to be a regression that was introduced in commit
9a9c6478 "nfsd: make NFSv4 recovery client tracking options per net".
Prior to that commit, it was safe to pass a NULL net pointer to
nfsd4_client_tracking_exit in the legacy recdir case, and
legacy_recdir_name_error did so. After that comit, the net pointer must
be valid.

This patch just fixes legacy_recdir_name_error to pass in a valid net
pointer to that function.

Cc: <stable@vger.kernel.org> # v3.8+
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
Reported-and-tested-by: NToralf Förster <toralf.foerster@gmx.de>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The Linux client is using CLAIM_FH to implement regular opens, not just
recovery cases, so it depends on the server to check permissions
correctly.

Therefore the owner override, which may make sense in the delegation
recovery case, isn't right in the CLAIM_FH case.

Symptoms: on a client with 49f9a0fa
"NFSv4.1: Enable open-by-filehandle", Bryan noticed this:

	touch test.txt
	chmod 000 test.txt
	echo test > test.txt

succeeding.

Cc: stable@kernel.org
Reported-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

If nfsd4_do_encode_secinfo() can't find GSS info that matches an
export security flavor, it assumes the flavor is not a GSS
pseudoflavor, and simply puts it on the wire.

However, if this XDR encoding logic is given a legitimate GSS
pseudoflavor but the RPC layer says it does not support that
pseudoflavor for some reason, then the server leaks GSS pseudoflavor
numbers onto the wire.

I confirmed this happens by blacklisting rpcsec_gss_krb5, then
attempted a client transition from the pseudo-fs to a Kerberos-only
share.  The client received a flavor list containing the Kerberos
pseudoflavor numbers, rather than GSS tuples.

The encoder logic can check that each pseudoflavor in flavs[] is
less than MAXFLAVOR before writing it into the buffer, to prevent
this.  But after "nflavs" is written into the XDR buffer, the
encoder can't skip writing flavor information into the buffer when
it discovers the RPC layer doesn't support that flavor.

So count the number of valid flavors as they are written into the
XDR buffer, then write that count into a placeholder in the XDR
buffer when all recognized flavors have been encoded.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Clean up.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

symbol 'nfsd_reply_cache_shrinker' only used within this file. It should
be static.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We're going out of our way here to remap an error to make rfc 3530
happy--but the rfc itself (nor rfc 1813, which has similar language)
gives no justification.  And disagrees with local filesystem behavior,
with Linux and posix man pages, and knfsd's implemented behavior for v2
and v3.

And the documented behavior seems better, in that it gives a little more
information--you could implement the 3530 behavior using the posix
behavior, but not the other way around.

Also, the Linux client makes no attempt to remap this error in the v4
case, so it can end up just returning EEXIST to the application in a
case where it should return EISDIR.

So honestly I think the rfc's are just buggy here--or in any case it
doesn't see worth the trouble to remap this error.
Reported-by: NFrank S Filz <ffilz@us.ibm.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NJeff Layton <jlayton@redhat.com>
Acked-by: N"J. Bruce Fields" <bfields@fieldses.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As 4.1 becomes less experimental and SSV still isn't implemented, we
have to admit it's not going to be, and return some sensible error
rather than just saying "our server's broken".  Discussion in the ietf
group hasn't turned up any objections to using NFS4ERR_ENC_ALG_UNSUPP
for that purpose.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We again check for the EXDEV a little later on, so the first check is
redundant.  This check is also slightly racier, since a badly timed
eviction from the export cache could leave us with the two fh_export
pointers pointing to two different cache entries which each refer to the
same underlying export.

It's better to compare vfsmounts as the later check does, but that
leaves a minor security hole in the case where the two exports refer to
two different directories especially if (for example) they have
different root-squashing options.

So, compare ex_path.dentry too.
Reported-by: NJoe Habermann <joe.habermann@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The seconds field of an nfstime4 structure is 64bit, but we are assuming
that the first 32bits are zero-filled.  So if the client tries to set
atime to a value before the epoch (touch -t 196001010101), then the
server will save the wrong value on disk.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Cc: stable@kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Cleanup a piece I forgot to remove in
9411b1d4 "nfsd4: cleanup handling of
nfsv4.0 closed stateid's".
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The "list_empty(&oo->oo_owner.so_stateids)" is aways true, so remove it.
Signed-off-by: Nfanchaoting <fanchaoting@cn.fujitsu.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

A 4.1 server must notify a client that has had any state revoked using
the SEQ4_STATUS_RECALLABLE_STATE_REVOKED flag.  The client can figure
out exactly which state is the problem using CHECK_STATEID and then free
it using FREE_STATEID.  The status flag will be unset once all such
revoked stateids are freed.

Our server's only recallable state is delegations.  So we keep with each
4.1 client a list of delegations that have timed out and been recalled,
but haven't yet been freed by FREE_STATEID.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The logic here is better expressed with a switch statement.

While we're here, CLOSED stateids (or stateids of an unkown type--which
would indicate a server bug) should probably return nfserr_bad_stateid,
though this behavior shouldn't affect any non-buggy client.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Make sure the client gives us an adequate backchannel.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Negotiation of the 4.1 session forechannel attributes is a mess.  Fix:

	- Move it all into check_forechannel_attrs instead of spreading
	  it between that, alloc_session, and init_forechannel_attrs.
	- set a minimum "slotsize" so that our drc memory limits apply
	  even for small maxresponsesize_cached.  This also fixes some
	  bugs when slotsize becomes <= 0.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Pass this struct by reference, not by value, and return an error instead
of a boolean to allow for future additions.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

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

Don't actually close any opens until we don't need them at all.

This means being left with write access when it's not really necessary,
but that's better than putting a file that might still have posix locks
held on it, as we have been.
Reported-by: NToralf Förster <toralf.foerster@gmx.de>
Cc: stable@kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

In the 4.1 case we're supposed to release lockowners as soon as they're
no longer used.

It would probably be more efficient to reference count them, but that's
slightly fiddly due to the need to have callbacks from locks.c to take
into account lock merging and splitting.

For most cases just scanning the inode's lock list on unlock for
matching locks will be sufficient.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

More logic that's unnecessary in the 4.1 case.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The replay_owner will never be used in the sessions case.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

memory allocated by kmem_cache_alloc() should be freed using
kmem_cache_free(), not kfree().
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: stable@kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>