When the passed token is longer than 4032 bytes, the remaining part
of the token must be copied from the rqstp->rq_arg.pages. But the
copy must make sure it happens in a consecutive way.

With the existing code, the first memcpy copies 'length' bytes from
argv->iobase, but since the header is in front, this never fills the
whole first page of in_token->pages.

The mecpy in the loop copies the following bytes, but starts writing at
the next page of in_token->pages.  This leaves the last bytes of page 0
unwritten.

Symptoms were that users with many groups were not able to access NFS
exports, when using Active Directory as the KDC.
Signed-off-by: Martijn de Gouw <martijn.de.gouw@prodrive-technologies.com>
Fixes: 5866efa8 "SUNRPC: Fix svcauth_gss_proxy_init()"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Its possible that using AUTH_SYS and mountd manage-gids option a
user may hit the 8k RPC channel buffer limit. This have been observed
on field, causing unanswered RPCs on clients after mountd fails to
write on channel :

rpc.mountd[11231]: auth_unix_gid: error writing reply

Userland nfs-utils uses a buffer size of 32k (RPC_CHAN_BUF_SIZE), so
lets match those two.
Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This was discovered using O_DIRECT at the client side, with small
unaligned file offsets or IOs that span multiple file pages.

Fixes: e248aa7b ("svcrdma: Remove max_sge check at connect time")
Signed-off-by: Dan Aloni <dan@kernelim.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Because every path through nfs4_find_file()'s
switch does an explicit return, the break is not needed.
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Fix returning value for sysctl sunrpc.transports.
Return error code from sysctl proc_handler function proc_do_xprt instead of number of the written bytes.
Otherwise sysctl returns random garbage for this key.

Since v1:
- Handle negative returned value from memory_read_from_buffer as an error
Signed-off-by: Artur Molchanov <arturmolchanov@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Reply to the client with multiple hole and data segments. I use the
result of the first vfs_llseek() call for encoding as an optimization so
we don't have to immediately repeat the call. This also lets us encode
any remaining reply as data if we get an unexpected result while trying
to calculate a hole.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

But only one of each right now. We'll expand on this in the next patch.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

However, we still only reply to the READ_PLUS call with a single segment
at this time.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This patch adds READ_PLUS support for returning a single
NFS4_CONTENT_DATA segment to the client. This is basically the same as
the READ operation, only with the extra information about data segments.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The original intent was presumably to reduce code duplication. The
trade-off was:

- No support for an NFSD proc function returning a non-success
  RPC accept_stat value.
- No support for void NFS replies to non-NULL procedures.
- Everyone pays for the deduplication with a few extra conditional
  branches in a hot path.

In addition, nfsd_dispatch() leaves *statp uninitialized in the
success path, unlike svc_generic_dispatch().

Address all of these problems by moving the logic for encoding
the NFS status code into the NFS XDR encoders themselves. Then
update the NFS .pc_func methods to return an RPC accept_stat
value.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Refactor: Handle this NFS version-specific mapping in the only
place where nfserr_wrongsec is generated.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Refactor: I'm about to change the return value from .pc_func. Clear
the way by replacing the RETURN_STATUS() macro with logic that
plants the status code directly into the response structure.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Remove special dispatcher logic for NFSv2 error responses. These are
rare to the point of becoming extinct, but all NFS responses have to
pay the cost of the extra conditional branches.

With this change, the NFSv2 error cases now get proper
xdr_ressize_check() calls.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

nfsd_release_fhandle() assumes that rqstp->rq_resp always points to
an nfsd_fhandle struct. In fact, no NFSv2 procedure uses struct
nfsd_fhandle as its response structure.

So far that has been "safe" to do because the res structs put the
resp->fh field at that same offset as struct nfsd_fhandle. I don't
think that's a guarantee, though, and there is certainly nothing
preventing a developer from altering the fields in those structures.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Clean up: These are not used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

nfsd_dispatch() is a hot path. Ensure the compiler takes the
processing of rare error cases out of line.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

For consistency and code legibility, use a similar organization of
variables as svc_generic_dispatch().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Add a documenting comment for the function. Remove comments that
simply describe obvious aspects of the code, but leave comments
that explain the differences in processing of each NFS version.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Reorder the arms so the compiler places checks for the most frequent
case first.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

nfsd_dispatch() is a hot path. Let's optimize the XDR method calls
for the by-far common case, which is that the XDR methods are indeed
present.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Clean up: Follow-up on ten-year-old commit b9081d90 ("NFS: kill
off complicated macro 'PROC'") by performing the same conversion in
the NFSACL code. To reduce the chance of error, I copied the original
C preprocessor output and then made some minor edits.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Clean up: Follow-up on ten-year-old commit b9081d90 ("NFS: kill
off complicated macro 'PROC'") by performing the same conversion in
the lockd code. To reduce the chance of error, I copied the original
C preprocessor output and then made some minor edits.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

There's no protection in nfsd_dispatch() against a NULL .pc_func
helpers. A malicious NFS client can trigger a crash by invoking the
unused/unsupported NFSv2 ROOT or WRITECACHE procedures.

The current NFSD dispatcher does not support returning a void reply
to a non-NULL procedure, so the reply to both of these is wrong, for
the moment.

Cc: <stable@vger.kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Since only the v4 code cares about it, maybe it's better to leave
rq_lease_breaker out of the common dispatch code?
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

There are actually rare races where this is possible (e.g. if a new open
intervenes between the read of i_writecount and the fi_fds).
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The nfsd open code has always kept separate read-only, read-write, and
write-only opens as necessary to ensure that when a client closes or
downgrades, we don't retain more access than necessary.

Also, I didn't realize the cache behaved this way when I wrote
94415b06 "nfsd4: a client's own opens needn't prevent delegations".
There I assumed fi_fds[O_WRONLY] and fi_fds[O_RDWR] would always be
distinct.  The violation of that assumption is triggering a
WARN_ON_ONCE() and could also cause the server to give out a delegation
when it shouldn't.

Fixes: 94415b06 ("nfsd4: a client's own opens needn't prevent delegations")
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Is it just me, or is the logic written in a slightly convoluted way?

I find it a little easier to read this way.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

seq_puts is a lot cheaper than seq_printf, so use that to print
literal strings.
Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

silence nfscache allocation warnings with kvzalloc

Currently nfsd_reply_cache_init attempts hash table allocation through
kmalloc, and manually falls back to vzalloc if that fails. This makes
the code a little larger than needed, and creates a significant amount
of serial console spam if you have enough systems.

Switching to kvzalloc gets rid of the allocation warnings, and makes
the code a little cleaner too as a side effect.

Freeing of nn->drc_hashtbl is already done using kvfree currently.
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Fixes coccicheck warning:

fs/nfsd/nfs4proc.c:3234:5-29: WARNING: Comparison to bool
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Squelch some sparse warnings:

/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1860:16: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1860:16:    expected int status
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1860:16:    got restricted __be32
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1862:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1862:24:    expected restricted __be32
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:1862:24:    got int status
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Squelch some sparse warnings:

/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4692:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4692:24:    expected int
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4692:24:    got restricted __be32 [usertype]
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4702:32: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4702:32:    expected int
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4702:32:    got restricted __be32 [usertype]
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4739:13: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4739:13:    expected restricted __be32 [usertype] err
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4739:13:    got int
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4891:15: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4891:15:    expected unsigned int [assigned] [usertype] count
/home/cel/src/linux/linux/fs/nfsd/nfs4xdr.c:4891:15:    got restricted __be32 [usertype]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Squelch some sparse warnings:

/home/cel/src/linux/linux/fs/nfsd/vfs.c:2264:13: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2264:13:    expected int err
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2264:13:    got restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2266:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2266:24:    expected restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2266:24:    got int err
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2288:13: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2288:13:    expected int err
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2288:13:    got restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2290:24: warning: incorrect type in return expression (different base types)
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2290:24:    expected restricted __be32
/home/cel/src/linux/linux/fs/nfsd/vfs.c:2290:24:    got int err
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Reserving space for a large READ payload requires special handling when
reserving space in the xdr buffer pages. One problem we can have is use
of the scratch buffer, which is used to get a pointer to a contiguous
region of data up to PAGE_SIZE. When using the scratch buffer, calls to
xdr_commit_encode() shift the data to it's proper alignment in the xdr
buffer. If we've reserved several pages in a vector, then this could
potentially invalidate earlier pointers and result in incorrect READ
data being sent to the client.

I get around this by looking at the amount of space left in the current
page, and never reserve more than that for each entry in the read
vector. This lets us place data directly where it needs to go in the
buffer pages.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Now when a read delegation is given, two delegation related traces
will be printed:

    nfsd_deleg_open: client 5f45b854:e6058001 stateid 00000030:00000001
    nfsd_deleg_none: client 5f45b854:e6058001 stateid 0000002f:00000001

Although the intention is to let developers know two stateid are
returned, the traces are confusing about whether or not a read delegation
is handled out. So renaming trace_nfsd_deleg_none() to trace_nfsd_open()
and trace_nfsd_deleg_open() to trace_nfsd_deleg_read() to make
the intension clearer.

The patched traces will be:

    nfsd_deleg_read: client 5f48a967:b55b21cd stateid 00000003:00000001
    nfsd_open: client 5f48a967:b55b21cd stateid 00000002:00000001
Suggested-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This draft is an official RFC now.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

It struck me while watching Jon Corbet ask how to keep kernel
Documentation up to date, that it might help if we were actually cc'd on
Documentation/filesystems/nfs/ changes.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

In nfsd4_encode_listxattrs(), the variable p is assigned to at one point
but this value is never used before p is reassigned. Fix this.

Addresses-Coverity: ("Unused value")
Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Drop duplicate words in net/sunrpc/.
Also fix "Anyone" to be "Any one".
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Missing "is".
Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>