Benny Halevy [Fri, 30 May 2014 13:09:27 +0000 (09:09 -0400)]
nfsd4: use recall_lock for delegation hashing
This fixes a bug in the handling of the fi_delegations list.
nfs4_setlease does not hold the recall_lock when adding to it. The
client_mutex is held, which prevents against concurrent list changes,
but nfsd_break_deleg_cb does not hold while walking it. New delegations
could theoretically creep onto the list while we're walking it there.
Signed-off-by: Benny Halevy <bhalevy@primarydata.com> Signed-off-by: Jeff Layton <jlayton@primarydata.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Jeff Layton [Fri, 30 May 2014 13:09:26 +0000 (09:09 -0400)]
nfsd: fix laundromat next-run-time calculation
The laundromat uses two variables to calculate when it should next run,
but one is completely ignored at the end of the run. Merge the two and
rename the variable to be more descriptive of what it does.
Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Kinglong Mee [Fri, 23 May 2014 12:54:27 +0000 (20:54 +0800)]
NFSD: Cleanup unneeded including net/ipv6.h
Commit 49b28684fdba ("nfsd: Remove deprecated nfsctl system call and
related code") removed the only use of ipv6_addr_set_v4mapped(), so
net/ipv6.h is unneeded now.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Kinglong Mee [Fri, 23 May 2014 12:53:05 +0000 (20:53 +0800)]
NFSD: remove unneeded linux/user_namespace.h include
After commit 4c1e1b34d5c8 ("nfsd: Store ex_anon_uid and ex_anon_gid as
kuids and kgids") using kuid/kgid for ex_anon_uid/ex_anon_gid,
user_namespace.h is not needed.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Kinglong Mee [Fri, 23 May 2014 11:57:49 +0000 (19:57 +0800)]
NFS4: Avoid NULL reference or double free in nfsd4_fslocs_free()
If fsloc_parse() failed at kzalloc(), fs/nfsd/export.c
411
412 fsloc->locations = kzalloc(fsloc->locations_count
413 * sizeof(struct nfsd4_fs_location), GFP_KERNEL);
414 if (!fsloc->locations)
415 return -ENOMEM;
svc_export_parse() will call nfsd4_fslocs_free() with fsloc->locations = NULL,
so that, "kfree(fsloc->locations[i].path);" will cause a crash.
If fsloc_parse() failed after that, fsloc_parse() will call nfsd4_fslocs_free(),
and svc_export_parse() will call it again, so that, a double free is caused.
This patch checks the fsloc->locations, and set to NULL after it be freed.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Mon, 12 May 2014 22:10:58 +0000 (18:10 -0400)]
nfsd4: better reservation of head space for krb5
RPC_MAX_AUTH_SIZE is scattered around several places. Better to set it
once in the auth code, where this kind of estimate should be made. And
while we're at it we can leave it zero when we're not using krb5i or
krb5p.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Thu, 8 May 2014 21:38:18 +0000 (17:38 -0400)]
nfsd4: really fix nfs4err_resource in 4.1 case
encode_getattr, for example, can return nfserr_resource to indicate it
ran out of buffer space. That's not a legal error in the 4.1 case.
And in the 4.1 case, if we ran out of buffer space, we should have
exceeded a session limit too.
(Note in 1bc49d83c37cfaf46be357757e592711e67f9809 "nfsd4: fix
nfs4err_resource in 4.1 case" we originally tried fixing this error
return before fixing the problem that we could error out while we still
had lots of available space. The result was to trade one illegal error
for another in those cases. We decided that was helpful, so reverted
the change in fc208d026be0c7d60db9118583fc62f6ca97743d, and are only
reinstating it now that we've elimited almost all of those cases.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Tue, 18 Mar 2014 21:44:10 +0000 (17:44 -0400)]
nfsd4: allow exotic read compounds
I'm not sure why a client would want to stuff multiple reads in a
single compound rpc, but it's legal for them to do it, and we should
really support it.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Tue, 4 Feb 2014 15:36:59 +0000 (10:36 -0500)]
nfsd4: turn off zero-copy-read in exotic cases
We currently allow only one read per compound, with operations before
and after whose responses will require no more than about a page to
encode.
While we don't expect clients to violate those limits any time soon,
this limitation isn't really condoned by the spec, so to future proof
the server we should lift the limitation.
At the same time we'd like to continue to support zero-copy reads.
Supporting multiple zero-copy-reads per compound would require a new
data structure to replace struct xdr_buf, which can represent only one
set of included pages.
So for now we plan to modify encode_read() to support either zero-copy
or non-zero-copy reads, and use some heuristics at the start of the
compound processing to decide whether a zero-copy read will work.
This will allow us to support more exotic compounds without introducing
a performance regression in the normal case.
Later patches handle those "exotic compounds", this one just makes sure
zero-copy is turned off in those cases.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Sun, 23 Mar 2014 16:01:48 +0000 (12:01 -0400)]
nfsd4: better estimate of getattr response size
We plan to use this estimate to decide whether or not to allow zero-copy
reads. Currently we're assuming all getattr's are a page, which can be
both too small (ACLs e.g. may be arbitrarily long) and too large (after
an upcoming read patch this will unnecessarily prevent zero copy reads
in any read compound also containing a getattr).
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Mon, 20 Jan 2014 22:08:27 +0000 (17:08 -0500)]
nfsd4: don't treat readlink like a zero-copy operation
There's no advantage to this zero-copy-style readlink encoding, and it
unnecessarily limits the kinds of compounds we can handle. (In practice
I can't see why a client would want e.g. multiple readlink calls in a
comound, but it's probably a spec violation for us not to handle it.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Fri, 21 Mar 2014 00:47:41 +0000 (20:47 -0400)]
nfsd4: use session limits to release send buffer reservation
Once we know the limits the session places on the size of the rpc, we
can also use that information to release any unnecessary reserved reply
buffer space.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Thu, 13 Mar 2014 01:39:35 +0000 (21:39 -0400)]
nfsd4: adjust buflen to session channel limit
We can simplify session limit enforcement by restricting the xdr buflen
to the session size.
Also fix a preexisting bug: we should really have been taking into
account the auth-required space when comparing against session limits,
which are limits on the size of the entire rpc reply, including any krb5
overhead.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Mon, 19 May 2014 20:18:23 +0000 (16:18 -0400)]
nfsd4: fix buflen calculation after read encoding
We don't necessarily want to assume that the buflen is the same
as the number of bytes available in the pages. We may have some reason
to set it to something less (for example, later patches will use a
smaller buflen to enforce session limits).
So, calculate the buflen relative to the previous buflen instead of
recalculating it from scratch.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Tue, 11 Mar 2014 19:39:13 +0000 (15:39 -0400)]
nfsd4: more precise nfsd4_max_reply
It will turn out to be useful to have a more accurate estimate of reply
size; so, piggyback on the existing op reply-size estimators.
Also move nfsd4_max_reply to nfs4proc.c to get easier access to struct
nfsd4_operation and friends. (Thanks to Christoph Hellwig for pointing
out that simplification.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Mon, 10 Mar 2014 16:19:10 +0000 (12:19 -0400)]
nfsd4: don't try to encode conflicting owner if low on space
I ran into this corner case in testing: in theory clients can provide
state owners up to 1024 bytes long. In the sessions case there might be
a risk of this pushing us over the DRC slot size.
The conflicting owner isn't really that important, so let's humor a
client that provides a small maxresponsize_cached by allowing ourselves
to return without the conflicting owner instead of outright failing the
operation.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Now that all op encoders can handle running out of space, we no longer
need to check the remaining size for every operation; only nonidempotent
operations need that check, and that can be done by
nfsd4_check_resp_size.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Sat, 22 Mar 2014 19:15:11 +0000 (15:15 -0400)]
nfsd4: reserve space before inlining 0-copy pages
Once we've included page-cache pages in the encoding it's difficult to
remove them and restart encoding. (xdr_truncate_encode doesn't handle
that case.) So, make sure we'll have adequate space to finish the
operation first.
For now COMPOUND_SLACK_SPACE checks should prevent this case happening,
but we want to remove those checks.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Thu, 30 Jan 2014 22:18:38 +0000 (17:18 -0500)]
nfsd4: teach encoders to handle reserve_space failures
We've tried to prevent running out of space with COMPOUND_SLACK_SPACE
and special checking in those operations (getattr) whose result can vary
enormously.
However:
- COMPOUND_SLACK_SPACE may be difficult to maintain as we add
more protocol.
- BUG_ON or page faulting on failure seems overly fragile.
- Especially in the 4.1 case, we prefer not to fail compounds
just because the returned result came *close* to session
limits. (Though perfect enforcement here may be difficult.)
- I'd prefer encoding to be uniform for all encoders instead of
having special exceptions for encoders containing, for
example, attributes.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Thu, 29 Aug 2013 19:42:52 +0000 (15:42 -0400)]
nfsd4: "backfill" using write_bytes_to_xdr_buf
Normally xdr encoding proceeds in a single pass from start of a buffer
to end, but sometimes we have to write a few bytes to an earlier
position.
Use write_bytes_to_xdr_buf for these cases rather than saving a pointer
to write to. We plan to rewrite xdr_reserve_space to handle encoding
across page boundaries using a scratch buffer, and don't want to risk
writing to a pointer that was contained in a scratch buffer.
Also it will no longer be safe to calculate lengths by subtracting two
pointers, so use xdr_buf offsets instead.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Tue, 25 Feb 2014 22:44:21 +0000 (17:44 -0500)]
rpc: xdr_truncate_encode
This will be used in the server side in a few cases:
- when certain operations (read, readdir, readlink) fail after
encoding a partial response.
- when we run out of space after encoding a partial response.
- in readlink, where we initially reserve PAGE_SIZE bytes for
data, then truncate to the actual size.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Wed, 28 Aug 2013 01:32:25 +0000 (21:32 -0400)]
nfsd4: use xdr_reserve_space in attribute encoding
This is a cosmetic change for now; no change in behavior.
Note we're just depending on xdr_reserve_space to do the bounds checking
for us, we're not really depending on its adjustment of iovec or xdr_buf
lengths yet, as those are fixed up by as necessary after the fact by
read-link operations and by nfs4svc_encode_compoundres. However we do
have to update xdr->iov on read-like operations to prevent
xdr_reserve_space from messing with the already-fixed-up length of the
the head.
When the attribute encoding fails partway through we have to undo the
length adjustments made so far. We do it manually for now, but later
patches will add an xdr_truncate_encode() helper to handle cases like
this.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Fri, 7 Mar 2014 01:39:29 +0000 (20:39 -0500)]
nfsd4: fix encoding of out-of-space replies
If nfsd4_check_resp_size() returns an error then we should really be
truncating the reply here, otherwise we may leave extra garbage at the
end of the rpc reply.
Also add a warning to catch any cases where our reply-size estimates may
be wrong in the case of a non-idempotent operation.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Tue, 21 Jan 2014 16:06:52 +0000 (11:06 -0500)]
nfsd4: reserve head space for krb5 integ/priv info
Currently if the nfs-level part of a reply would be too large, we'll
return an error to the client. But if the nfs-level part fits and
leaves no room for krb5p or krb5i stuff, then we just drop the request
entirely.
That's no good. Instead, reserve some slack space at the end of the
buffer and make sure we fail outright if we'd come close.
The slack space here is a massive overstimate of what's required, we
should probably try for a tighter limit at some point.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Mon, 19 May 2014 16:27:11 +0000 (12:27 -0400)]
nfsd4: decoding errors can still be cached and require space
Currently a non-idempotent op reply may be cached if it fails in the
proc code but not if it fails at xdr decoding. I doubt there are any
xdr-decoding-time errors that would make this a problem in practice, so
this probably isn't a serious bug.
The space estimates should also take into account space required for
encoding of error returns. Again, not a practical problem, though it
would become one after future patches which will tighten the space
estimates.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Wed, 12 Mar 2014 19:17:18 +0000 (15:17 -0400)]
nfsd4: allow larger 4.1 session drc slots
The client is actually asking for 2532 bytes. I suspect that's a
mistake. But maybe we can allow some more. In theory lock needs more
if it might return a maximum-length lockowner in the denied case.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NeilBrown [Mon, 12 May 2014 01:22:47 +0000 (11:22 +1000)]
nfsd: Only set PF_LESS_THROTTLE when really needed.
PF_LESS_THROTTLE has a very specific use case: to avoid deadlocks
and live-locks while writing to the page cache in a loop-back
NFS mount situation.
It therefore makes sense to *only* set PF_LESS_THROTTLE in this
situation.
We now know when a request came from the local-host so it could be a
loop-back mount. We already know when we are handling write requests,
and when we are doing anything else.
So combine those two to allow nfsd to still be throttled (like any
other process) in every situation except when it is known to be
problematic.
Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NeilBrown [Mon, 12 May 2014 01:22:47 +0000 (11:22 +1000)]
SUNRPC: track whether a request is coming from a loop-back interface.
If an incoming NFS request is coming from the local host, then
nfsd will need to perform some special handling. So detect that
possibility and make the source visible in rq_local.
Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Chuck Lever [Mon, 19 May 2014 17:40:22 +0000 (13:40 -0400)]
NFSD: Ignore client's source port on RDMA transports
An NFS/RDMA client's source port is meaningless for RDMA transports.
The transport layer typically sets the source port value on the
connection to a random ephemeral port.
Currently, NFS server administrators must specify the "insecure"
export option to enable clients to access exports via RDMA.
But this means NFS clients can access such an export via IP using an
ephemeral port, which may not be desirable.
This patch eliminates the need to specify the "insecure" export
option to allow NFS/RDMA clients access to an export.
J. Bruce Fields [Mon, 3 Mar 2014 17:19:18 +0000 (12:19 -0500)]
nfsd4: fix delegation cleanup on error
We're not cleaning up everything we need to on error. In particular,
we're not removing our lease. Among other problems this can cause the
struct nfs4_file used as fl_owner to be referenced after it has been
destroyed.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Kinglong Mee [Fri, 18 Apr 2014 16:17:31 +0000 (00:17 +0800)]
NFSD: Don't clear SUID/SGID after root writing data
We're clearing the SUID/SGID bits on write by hand in nfsd_vfs_write,
even though the subsequent vfs_writev() call will end up doing this for
us (through file system write methods eventually calling
file_remove_suid(), e.g., from __generic_file_aio_write).
So, remove the redundant nfsd code.
The only change in behavior is when the write is by root, in which case
we previously cleared SUID/SGID, but will now leave it alone. The new
behavior is the behavior of every filesystem we've checked.
It seems better to be consistent with local filesystem behavior. And
the security advantage seems limited as root could always restore these
bits by hand if it wanted.
J. Bruce Fields [Tue, 20 May 2014 19:55:21 +0000 (15:55 -0400)]
nfsd4: remove lockowner when removing lock stateid
The nfsv4 state code has always assumed a one-to-one correspondance
between lock stateid's and lockowners even if it appears not to in some
places.
We may actually change that, but for now when FREE_STATEID releases a
lock stateid it also needs to release the parent lockowner.
Symptoms were a subsequent LOCK crashing in find_lockowner_str when it
calls same_lockowner_ino on a lockowner that unexpectedly has an empty
so_stateids list.
Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Thu, 15 May 2014 01:57:26 +0000 (21:57 -0400)]
nfsd4: fix corruption on setting an ACL.
As of 06f9cc12caa862f5bc86ebdb4f77568a4bef0167 "nfsd4: don't create
unnecessary mask acl", any non-trivial ACL will be left with an
unitialized entry, and a trivial ACL may write one entry beyond what's
allocated.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Use fh_fsid when reffering to the fsid part of the filehandle. The
variable length auth field envisioned in nfsfh wasn't ever implemented.
Also clean up some lose ends around this and document the file handle
format better.
Btw, why do we even export nfsfh.h to userspace? The file handle very
much is kernel private, and nothing in nfs-utils include the header
either.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The only real user of this header is fs/nfsd/nfsfh.h, so merge the
two. Various lockѕ source files used it to indirectly get other
sunrpc or nfs headers, so fix those up.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NFSd: Move default initialisers from create_client() to alloc_client()
Aside from making it clearer what is non-trivial in create_client(), it
also fixes a bug whereby we can call free_client() before idr_init()
has been called.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
J. Bruce Fields [Wed, 9 Apr 2014 15:07:01 +0000 (11:07 -0400)]
Revert "nfsd4: fix nfs4err_resource in 4.1 case"
Since we're still limiting attributes to a page, the result here is that
a large getattr result will return NFS4ERR_REP_TOO_BIG/TOO_BIG_TO_CACHE
instead of NFS4ERR_RESOURCE.
Both error returns are wrong, and the real bug here is the arbitrary
limit on getattr results, fixed by as-yet out-of-tree patches. But at a
minimum we can make life easier for clients by sticking to one broken
behavior in released kernels instead of two....
Trond says:
one immediate consequence of this patch will be that NFSv4.1
clients will now report EIO instead of EREMOTEIO if they hit the
problem. That may make debugging a little less obvious.
Another consequence will be that if we ever do try to add client
side handling of NFS4ERR_REP_TOO_BIG, then we now have to deal
with the “handle existing buggy server” syndrome.
Reported-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Jeff Layton [Tue, 15 Apr 2014 12:51:48 +0000 (08:51 -0400)]
nfsd: set timeparms.to_maxval in setup_callback_client
...otherwise the logic in the timeout handling doesn't work correctly.
Spotted-by: Trond Myklebust <trond.myklebust@primarydata.com> Cc: stable@vger.kernel.org Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Jeff Layton [Tue, 15 Apr 2014 12:44:12 +0000 (08:44 -0400)]
locks: allow __break_lease to sleep even when break_time is 0
A fl->fl_break_time of 0 has a special meaning to the lease break code
that basically means "never break the lease". knfsd uses this to ensure
that leases don't disappear out from under it.
Unfortunately, the code in __break_lease can end up passing this value
to wait_event_interruptible as a timeout, which prevents it from going
to sleep at all. This causes __break_lease to spin in a tight loop and
causes soft lockups.
Fix this by ensuring that we pass a minimum value of 1 as a timeout
instead.
Cc: <stable@vger.kernel.org> Cc: J. Bruce Fields <bfields@fieldses.org> Reported-by: Terry Barnaby <terry1@beam.ltd.uk> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
projects / linux-beck.git / log